Merge branch 'main' of 91.92.155.224:Innovenergy/Innovenergy_trunk

csharp/App/Backend/Controller.cs

@@ -901,7 +901,8 @@ public class Controller : ControllerBase
     /// Returns JSON with daily data, weekly totals, ratios, and AI insight.
     /// </summary>
     [HttpGet(nameof(GetWeeklyReport))]
-    public async Task<ActionResult<WeeklyReportResponse>> GetWeeklyReport(Int64 installationId, Token authToken, string? language = null)
+    public async Task<ActionResult<WeeklyReportResponse>> GetWeeklyReport(
+        Int64 installationId, Token authToken, String? language = null, String? weekStart = null)
     {
         var user = Db.GetSession(authToken)?.User;
         if (user == null)
@@ -911,14 +912,24 @@ public class Controller : ControllerBase
         if (installation is null || !user.HasAccessTo(installation))
             return Unauthorized();
 
-        var filePath = Environment.CurrentDirectory + "/tmp_report/" + installationId + ".xlsx";
+        // Parse optional weekStart override (must be a Monday; any valid date accepted for flexibility)
-        if (!System.IO.File.Exists(filePath))
+        DateOnly? weekStartDate = null;
-            return NotFound($"No report data file found. Please place the Excel export at: tmp_report/{installationId}.xlsx");
+        if (!String.IsNullOrEmpty(weekStart))
+        {
+            if (!DateOnly.TryParseExact(weekStart, "yyyy-MM-dd", out var parsed))
+                return BadRequest("weekStart must be in yyyy-MM-dd format.");
+            weekStartDate = parsed;
+        }
 
         try
         {
             var lang   = language ?? user.Language ?? "en";
-            var report = await WeeklyReportService.GenerateReportAsync(installationId, installation.InstallationName, lang);
+            var report = await WeeklyReportService.GenerateReportAsync(
+                installationId, installation.InstallationName, lang, weekStartDate);
+
+            // Persist weekly summary and seed AiInsightCache for this language
+            ReportAggregationService.SaveWeeklySummary(installationId, report, lang);
+
             return Ok(report);
         }
         catch (Exception ex)
@@ -956,6 +967,329 @@ public class Controller : ControllerBase
         }
     }
 
+    // ── Monthly & Yearly Reports ─────────────────────────────────────
+
+    [HttpGet(nameof(GetPendingMonthlyAggregations))]
+    public ActionResult<List<PendingMonth>> GetPendingMonthlyAggregations(Int64 installationId, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        return Ok(ReportAggregationService.GetPendingMonthlyAggregations(installationId));
+    }
+
+    [HttpGet(nameof(GetPendingYearlyAggregations))]
+    public ActionResult<List<PendingYear>> GetPendingYearlyAggregations(Int64 installationId, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        return Ok(ReportAggregationService.GetPendingYearlyAggregations(installationId));
+    }
+
+    [HttpGet(nameof(GetMonthlyReports))]
+    public async Task<ActionResult<List<MonthlyReportSummary>>> GetMonthlyReports(
+        Int64 installationId, Token authToken, String? language = null)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        var lang    = language ?? user.Language ?? "en";
+        var reports = Db.GetMonthlyReports(installationId);
+        foreach (var report in reports)
+            report.AiInsight = await ReportAggregationService.GetOrGenerateMonthlyInsightAsync(report, lang);
+        return Ok(reports);
+    }
+
+    [HttpGet(nameof(GetYearlyReports))]
+    public async Task<ActionResult<List<YearlyReportSummary>>> GetYearlyReports(
+        Int64 installationId, Token authToken, String? language = null)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        var lang    = language ?? user.Language ?? "en";
+        var reports = Db.GetYearlyReports(installationId);
+        foreach (var report in reports)
+            report.AiInsight = await ReportAggregationService.GetOrGenerateYearlyInsightAsync(report, lang);
+        return Ok(reports);
+    }
+
+    /// <summary>
+    /// Manually trigger monthly aggregation for an installation.
+    /// Computes monthly report from daily records for the specified year/month.
+    /// </summary>
+    [HttpPost(nameof(TriggerMonthlyAggregation))]
+    public async Task<ActionResult> TriggerMonthlyAggregation(Int64 installationId, Int32 year, Int32 month, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        if (month < 1 || month > 12)
+            return BadRequest("Month must be between 1 and 12.");
+
+        try
+        {
+            var lang      = user.Language ?? "en";
+            var dayCount  = await ReportAggregationService.TriggerMonthlyAggregationAsync(installationId, year, month, lang);
+            if (dayCount == 0)
+                return NotFound($"No daily records found for {year}-{month:D2}.");
+
+            return Ok(new { message = $"Monthly report created from {dayCount} daily records for {year}-{month:D2}." });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[TriggerMonthlyAggregation] Error: {ex.Message}");
+            return BadRequest($"Failed to aggregate: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Manually trigger yearly aggregation for an installation.
+    /// Aggregates monthly reports for the specified year into a yearly report.
+    /// </summary>
+    [HttpPost(nameof(TriggerYearlyAggregation))]
+    public async Task<ActionResult> TriggerYearlyAggregation(Int64 installationId, Int32 year, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        try
+        {
+            var lang       = user.Language ?? "en";
+            var monthCount = await ReportAggregationService.TriggerYearlyAggregationAsync(installationId, year, lang);
+            if (monthCount == 0)
+                return NotFound($"No monthly reports found for {year}.");
+
+            return Ok(new { message = $"Yearly report created from {monthCount} monthly reports for {year}." });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[TriggerYearlyAggregation] Error: {ex.Message}");
+            return BadRequest($"Failed to aggregate: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Manually trigger xlsx ingestion for all SodioHome installations.
+    /// Scans tmp_report/ for all matching xlsx files and ingests any new days.
+    /// </summary>
+    [HttpPost(nameof(IngestAllDailyData))]
+    public async Task<ActionResult> IngestAllDailyData(Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        try
+        {
+            await DailyIngestionService.IngestAllInstallationsAsync();
+            return Ok(new { message = "Daily data ingestion triggered for all installations." });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[IngestAllDailyData] Error: {ex.Message}");
+            return BadRequest($"Failed to ingest: {ex.Message}");
+        }
+    }
+
+    /// <summary>
+    /// Manually trigger xlsx ingestion for one installation.
+    /// Parses tmp_report/{installationId}*.xlsx and stores any new days in DailyEnergyRecord.
+    /// </summary>
+    [HttpPost(nameof(IngestDailyData))]
+    public async Task<ActionResult> IngestDailyData(Int64 installationId, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        try
+        {
+            await DailyIngestionService.IngestInstallationAsync(installationId);
+            return Ok(new { message = $"Daily data ingestion triggered for installation {installationId}." });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[IngestDailyData] Error: {ex.Message}");
+            return BadRequest($"Failed to ingest: {ex.Message}");
+        }
+    }
+
+    // ── Debug / Inspection Endpoints ──────────────────────────────────
+
+    /// <summary>
+    /// Returns the stored DailyEnergyRecord rows for an installation and date range.
+    /// Use this to verify that xlsx ingestion worked correctly before generating reports.
+    /// </summary>
+    [HttpGet(nameof(GetDailyRecords))]
+    public ActionResult<List<DailyEnergyRecord>> GetDailyRecords(
+        Int64 installationId, String from, String to, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        if (!DateOnly.TryParseExact(from, "yyyy-MM-dd", out var fromDate) ||
+            !DateOnly.TryParseExact(to,   "yyyy-MM-dd", out var toDate))
+            return BadRequest("from and to must be in yyyy-MM-dd format.");
+
+        var records = Db.GetDailyRecords(installationId, fromDate, toDate);
+        return Ok(new { count = records.Count, records });
+    }
+
+    /// <summary>
+    /// Deletes DailyEnergyRecord rows for an installation in the given date range.
+    /// Safe to use during testing — only removes daily records, not report summaries.
+    /// Allows re-ingesting the same xlsx files after correcting data.
+    /// </summary>
+    [HttpDelete(nameof(DeleteDailyRecords))]
+    public ActionResult DeleteDailyRecords(
+        Int64 installationId, String from, String to, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        if (!DateOnly.TryParseExact(from, "yyyy-MM-dd", out var fromDate) ||
+            !DateOnly.TryParseExact(to,   "yyyy-MM-dd", out var toDate))
+            return BadRequest("from and to must be in yyyy-MM-dd format.");
+
+        var fromStr  = fromDate.ToString("yyyy-MM-dd");
+        var toStr    = toDate.ToString("yyyy-MM-dd");
+        var toDelete = Db.DailyRecords
+            .Where(r => r.InstallationId == installationId)
+            .ToList()
+            .Where(r => String.Compare(r.Date, fromStr, StringComparison.Ordinal) >= 0
+                     && String.Compare(r.Date, toStr,   StringComparison.Ordinal) <= 0)
+            .ToList();
+
+        foreach (var record in toDelete)
+            Db.DailyRecords.Delete(r => r.Id == record.Id);
+
+        Console.WriteLine($"[DeleteDailyRecords] Deleted {toDelete.Count} records for installation {installationId} ({from}–{to}).");
+        return Ok(new { deleted = toDelete.Count, from, to });
+    }
+
+    [HttpPost(nameof(SendMonthlyReportEmail))]
+    public async Task<ActionResult> SendMonthlyReportEmail(Int64 installationId, Int32 year, Int32 month, String emailAddress, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        var report = Db.GetMonthlyReports(installationId).FirstOrDefault(r => r.Year == year && r.Month == month);
+        if (report == null)
+            return BadRequest($"No monthly report found for {year}-{month:D2}.");
+
+        try
+        {
+            var lang = user.Language ?? "en";
+            report.AiInsight = await ReportAggregationService.GetOrGenerateMonthlyInsightAsync(report, lang);
+            await ReportEmailService.SendMonthlyReportEmailAsync(report, installation.InstallationName, emailAddress, lang);
+            return Ok(new { message = $"Monthly report sent to {emailAddress}" });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[SendMonthlyReportEmail] Error: {ex.Message}");
+            return BadRequest($"Failed to send report: {ex.Message}");
+        }
+    }
+
+    [HttpPost(nameof(SendYearlyReportEmail))]
+    public async Task<ActionResult> SendYearlyReportEmail(Int64 installationId, Int32 year, String emailAddress, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        var report = Db.GetYearlyReports(installationId).FirstOrDefault(r => r.Year == year);
+        if (report == null)
+            return BadRequest($"No yearly report found for {year}.");
+
+        try
+        {
+            var lang = user.Language ?? "en";
+            report.AiInsight = await ReportAggregationService.GetOrGenerateYearlyInsightAsync(report, lang);
+            await ReportEmailService.SendYearlyReportEmailAsync(report, installation.InstallationName, emailAddress, lang);
+            return Ok(new { message = $"Yearly report sent to {emailAddress}" });
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[SendYearlyReportEmail] Error: {ex.Message}");
+            return BadRequest($"Failed to send report: {ex.Message}");
+        }
+    }
+
+    [HttpGet(nameof(GetWeeklyReportSummaries))]
+    public async Task<ActionResult<List<WeeklyReportSummary>>> GetWeeklyReportSummaries(
+        Int64 installationId, Int32 year, Int32 month, Token authToken, String? language = null)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user == null)
+            return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null || !user.HasAccessTo(installation))
+            return Unauthorized();
+
+        var lang      = language ?? user.Language ?? "en";
+        var summaries = Db.GetWeeklyReportsForMonth(installationId, year, month);
+        foreach (var s in summaries)
+            s.AiInsight = await ReportAggregationService.GetOrGenerateWeeklyInsightAsync(s, lang);
+        return Ok(summaries);
+    }
+
     [HttpPut(nameof(UpdateFolder))]
     public ActionResult<Folder> UpdateFolder([FromBody] Folder folder, Token authToken)
     {

csharp/App/Backend/DataTypes/AiInsightCache.cs

@@ -0,0 +1,29 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+/// <summary>
+/// Per-language AI insight cache for weekly, monthly, and yearly report summaries.
+/// Keyed by (ReportType, ReportId, Language) — generated once on first request per language,
+/// then reused for UI reads and email sends. Never store language-specific text in the
+/// summary tables themselves; always go through this cache.
+/// </summary>
+public class AiInsightCache
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64  Id          { get; set; }
+
+    /// <summary>"weekly" | "monthly" | "yearly"</summary>
+    [Indexed]
+    public String ReportType  { get; set; } = "";
+
+    /// <summary>FK to WeeklyReportSummary.Id / MonthlyReportSummary.Id / YearlyReportSummary.Id</summary>
+    [Indexed]
+    public Int64  ReportId    { get; set; }
+
+    /// <summary>ISO 639-1 language code: "en" | "de" | "fr" | "it"</summary>
+    public String Language    { get; set; } = "en";
+
+    public String InsightText { get; set; } = "";
+    public String CreatedAt   { get; set; } = "";
+}

csharp/App/Backend/DataTypes/DailyEnergyRecord.cs

@@ -0,0 +1,31 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+/// <summary>
+/// Raw daily energy totals for one installation and calendar day.
+/// Source of truth for weekly and monthly report generation.
+/// Populated by DailyIngestionService from xlsx (current) or S3 (future).
+/// Retention: 1 year (cleaned up annually on Jan 2).
+/// </summary>
+public class DailyEnergyRecord
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64  Id                  { get; set; }
+
+    [Indexed]
+    public Int64  InstallationId      { get; set; }
+
+    // ISO date string: "YYYY-MM-DD"
+    public String Date                { get; set; } = "";
+
+    // Energy totals (kWh) — cumulative for the full calendar day
+    public Double PvProduction        { get; set; }
+    public Double LoadConsumption     { get; set; }
+    public Double GridImport          { get; set; }
+    public Double GridExport          { get; set; }
+    public Double BatteryCharged      { get; set; }
+    public Double BatteryDischarged   { get; set; }
+
+    public String CreatedAt           { get; set; } = "";
+}

csharp/App/Backend/DataTypes/HourlyEnergyRecord.cs

@@ -0,0 +1,37 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+public class HourlyEnergyRecord
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64   Id                   { get; set; }
+
+    [Indexed]
+    public Int64   InstallationId       { get; set; }
+
+    // "YYYY-MM-DD" — used for range queries (same pattern as DailyEnergyRecord)
+    [Indexed]
+    public String  Date                 { get; set; } = "";
+
+    // 0–23
+    public Int32   Hour                 { get; set; }
+
+    // "YYYY-MM-DD HH" — used for idempotency check
+    public String  DateHour             { get; set; } = "";
+
+    public String  DayOfWeek            { get; set; } = "";
+    public Boolean IsWeekend            { get; set; }
+
+    // Energy for this hour (kWh)
+    public Double  PvKwh                { get; set; }
+    public Double  LoadKwh              { get; set; }
+    public Double  GridImportKwh        { get; set; }
+    public Double  BatteryChargedKwh    { get; set; }
+    public Double  BatteryDischargedKwh { get; set; }
+
+    // Instantaneous state of charge at snapshot time (%)
+    public Double  BattSoC              { get; set; }
+
+    public String  CreatedAt            { get; set; } = "";
+}

csharp/App/Backend/DataTypes/ReportSummary.cs

@@ -0,0 +1,149 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+/// <summary>
+/// Stored summary for a weekly report period.
+/// Created when GetWeeklyReport is called. Consumed and deleted by monthly aggregation.
+/// </summary>
+public class WeeklyReportSummary
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64  Id                      { get; set; }
+
+    [Indexed]
+    public Int64  InstallationId          { get; set; }
+
+    // Period boundaries (ISO date strings: "2026-02-10")
+    public String PeriodStart             { get; set; } = "";
+    public String PeriodEnd               { get; set; } = "";
+
+    // Energy totals (kWh)
+    public Double TotalPvProduction       { get; set; }
+    public Double TotalConsumption        { get; set; }
+    public Double TotalGridImport         { get; set; }
+    public Double TotalGridExport         { get; set; }
+    public Double TotalBatteryCharged     { get; set; }
+    public Double TotalBatteryDischarged  { get; set; }
+
+    // Derived metrics
+    public Double TotalEnergySaved        { get; set; }
+    public Double TotalSavingsCHF         { get; set; }
+    public Double SelfSufficiencyPercent  { get; set; }
+    public Double SelfConsumptionPercent  { get; set; }
+    public Double BatteryEfficiencyPercent { get; set; }
+    public Double GridDependencyPercent   { get; set; }
+
+    // Behavioral highlights
+    public Int32  PeakLoadHour            { get; set; }
+    public Int32  PeakSolarHour           { get; set; }
+    public Double WeekdayAvgDailyLoad     { get; set; }
+    public Double WeekendAvgDailyLoad     { get; set; }
+
+    // AI insight for this week
+    public String AiInsight               { get; set; } = "";
+
+    public String CreatedAt               { get; set; } = "";
+}
+
+/// <summary>
+/// Aggregated monthly report. Created from weekly summaries at month-end.
+/// Consumed and deleted by yearly aggregation.
+/// </summary>
+public class MonthlyReportSummary
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64  Id                      { get; set; }
+
+    [Indexed]
+    public Int64  InstallationId          { get; set; }
+
+    public Int32  Year                    { get; set; }
+    public Int32  Month                   { get; set; }
+    public String PeriodStart             { get; set; } = "";
+    public String PeriodEnd               { get; set; } = "";
+
+    // Aggregated energy totals
+    public Double TotalPvProduction       { get; set; }
+    public Double TotalConsumption        { get; set; }
+    public Double TotalGridImport         { get; set; }
+    public Double TotalGridExport         { get; set; }
+    public Double TotalBatteryCharged     { get; set; }
+    public Double TotalBatteryDischarged  { get; set; }
+
+    // Re-derived from aggregated totals
+    public Double TotalEnergySaved        { get; set; }
+    public Double TotalSavingsCHF         { get; set; }
+    public Double SelfSufficiencyPercent  { get; set; }
+    public Double SelfConsumptionPercent  { get; set; }
+    public Double BatteryEfficiencyPercent { get; set; }
+    public Double GridDependencyPercent   { get; set; }
+
+    // Averaged behavioral highlights
+    public Int32  AvgPeakLoadHour         { get; set; }
+    public Int32  AvgPeakSolarHour        { get; set; }
+    public Double AvgWeekdayDailyLoad     { get; set; }
+    public Double AvgWeekendDailyLoad     { get; set; }
+
+    public Int32  WeekCount               { get; set; }
+    public String AiInsight               { get; set; } = "";
+    public String CreatedAt               { get; set; } = "";
+}
+
+/// <summary>
+/// Aggregated yearly report. Created from monthly summaries at year-end.
+/// Kept indefinitely.
+/// </summary>
+public class YearlyReportSummary
+{
+    [PrimaryKey, AutoIncrement]
+    public Int64  Id                      { get; set; }
+
+    [Indexed]
+    public Int64  InstallationId          { get; set; }
+
+    public Int32  Year                    { get; set; }
+    public String PeriodStart             { get; set; } = "";
+    public String PeriodEnd               { get; set; } = "";
+
+    // Aggregated energy totals
+    public Double TotalPvProduction       { get; set; }
+    public Double TotalConsumption        { get; set; }
+    public Double TotalGridImport         { get; set; }
+    public Double TotalGridExport         { get; set; }
+    public Double TotalBatteryCharged     { get; set; }
+    public Double TotalBatteryDischarged  { get; set; }
+
+    // Re-derived from aggregated totals
+    public Double TotalEnergySaved        { get; set; }
+    public Double TotalSavingsCHF         { get; set; }
+    public Double SelfSufficiencyPercent  { get; set; }
+    public Double SelfConsumptionPercent  { get; set; }
+    public Double BatteryEfficiencyPercent { get; set; }
+    public Double GridDependencyPercent   { get; set; }
+
+    // Averaged behavioral highlights
+    public Int32  AvgPeakLoadHour         { get; set; }
+    public Int32  AvgPeakSolarHour        { get; set; }
+    public Double AvgWeekdayDailyLoad     { get; set; }
+    public Double AvgWeekendDailyLoad     { get; set; }
+
+    public Int32  MonthCount              { get; set; }
+    public String AiInsight               { get; set; } = "";
+    public String CreatedAt               { get; set; } = "";
+}
+
+// ── DTOs for pending aggregation queries (not stored in DB) ──
+
+public class PendingMonth
+{
+    public Int32 Year      { get; set; }
+    public Int32 Month     { get; set; }
+    public Int32 WeekCount { get; set; }
+}
+
+public class PendingYear
+{
+    public Int32 Year       { get; set; }
+    public Int32 MonthCount { get; set; }
+}

csharp/App/Backend/Database/Create.cs

@@ -68,6 +68,13 @@ public static partial class Db
          return Insert(action);
     }
 
+    public static Boolean Create(WeeklyReportSummary report)  => Insert(report);
+    public static Boolean Create(MonthlyReportSummary report) => Insert(report);
+    public static Boolean Create(YearlyReportSummary report)  => Insert(report);
+    public static Boolean Create(DailyEnergyRecord record)    => Insert(record);
+    public static Boolean Create(HourlyEnergyRecord record)   => Insert(record);
+    public static Boolean Create(AiInsightCache cache)        => Insert(cache);
+    
     public static void HandleAction(UserAction newAction)
     {
         //Find the total number of actions for this installation

csharp/App/Backend/Database/Db.cs

@@ -25,6 +25,12 @@ public static partial class Db
     public static TableQuery<Error> Errors => Connection.Table<Error>();
     public static TableQuery<Warning> Warnings => Connection.Table<Warning>();
     public static TableQuery<UserAction> UserActions => Connection.Table<UserAction>();
+    public static TableQuery<WeeklyReportSummary>  WeeklyReports  => Connection.Table<WeeklyReportSummary>();
+    public static TableQuery<MonthlyReportSummary> MonthlyReports => Connection.Table<MonthlyReportSummary>();
+    public static TableQuery<YearlyReportSummary>  YearlyReports  => Connection.Table<YearlyReportSummary>();
+    public static TableQuery<DailyEnergyRecord>    DailyRecords      => Connection.Table<DailyEnergyRecord>();
+    public static TableQuery<HourlyEnergyRecord>   HourlyRecords     => Connection.Table<HourlyEnergyRecord>();
+    public static TableQuery<AiInsightCache>       AiInsightCaches   => Connection.Table<AiInsightCache>();
 
 
     public static void Init()
@@ -51,6 +57,12 @@ public static partial class Db
             Connection.CreateTable<Error>();
             Connection.CreateTable<Warning>();
             Connection.CreateTable<UserAction>();
+            Connection.CreateTable<WeeklyReportSummary>();
+            Connection.CreateTable<MonthlyReportSummary>();
+            Connection.CreateTable<YearlyReportSummary>();
+            Connection.CreateTable<DailyEnergyRecord>();
+            Connection.CreateTable<HourlyEnergyRecord>();
+            Connection.CreateTable<AiInsightCache>();
         });
         
         // One-time migration: normalize legacy long-form language values to ISO codes
@@ -88,6 +100,12 @@ public static partial class Db
         fileConnection.CreateTable<Error>();
         fileConnection.CreateTable<Warning>();
         fileConnection.CreateTable<UserAction>();
+        fileConnection.CreateTable<WeeklyReportSummary>();
+        fileConnection.CreateTable<MonthlyReportSummary>();
+        fileConnection.CreateTable<YearlyReportSummary>();
+        fileConnection.CreateTable<DailyEnergyRecord>();
+        fileConnection.CreateTable<HourlyEnergyRecord>();
+        fileConnection.CreateTable<AiInsightCache>();
 
         return fileConnection;
         //return CopyDbToMemory(fileConnection);

csharp/App/Backend/Database/Delete.cs

@@ -141,4 +141,106 @@ public static partial class Db
     {
         OrderNumber2Installation.Delete(s => s.InstallationId == relation.InstallationId && s.OrderNumber == relation.OrderNumber);
     }
+
+    public static void DeleteWeeklyReportsForMonth(Int64 installationId, Int32 year, Int32 month)
+    {
+        var monthStart = $"{year:D4}-{month:D2}-01";
+        var monthEnd   = month == 12 ? $"{year + 1:D4}-01-01" : $"{year:D4}-{month + 1:D2}-01";
+
+        // SQLite-net doesn't support string comparison in Delete lambda,
+        // so fetch matching IDs first, then delete by ID.
+        var ids = WeeklyReports
+            .Where(r => r.InstallationId == installationId)
+            .ToList()
+            .Where(r => String.Compare(r.PeriodStart, monthStart, StringComparison.Ordinal) >= 0
+                     && String.Compare(r.PeriodStart, monthEnd,   StringComparison.Ordinal) <  0)
+            .Select(r => r.Id)
+            .ToList();
+
+        foreach (var id in ids)
+            WeeklyReports.Delete(r => r.Id == id);
+
+        if (ids.Count > 0) Backup();
+    }
+
+    public static void DeleteMonthlyReportsForYear(Int64 installationId, Int32 year)
+    {
+        MonthlyReports.Delete(r => r.InstallationId == installationId && r.Year == year);
+        Backup();
+    }
+
+    public static void DeleteMonthlyReport(Int64 installationId, Int32 year, Int32 month)
+    {
+        var count = MonthlyReports.Delete(r => r.InstallationId == installationId && r.Year == year && r.Month == month);
+        if (count > 0) Backup();
+    }
+
+    public static void DeleteYearlyReport(Int64 installationId, Int32 year)
+    {
+        var count = YearlyReports.Delete(r => r.InstallationId == installationId && r.Year == year);
+        if (count > 0) Backup();
+    }
+
+    /// <summary>
+    /// Deletes all report records older than 1 year. Called annually on Jan 2
+    /// after yearly reports are created. Uses fetch-then-delete for string-compared
+    /// date fields (SQLite-net doesn't support string comparisons in Delete lambdas).
+    /// </summary>
+    public static void CleanupOldData()
+    {
+        var cutoff   = DateOnly.FromDateTime(DateTime.UtcNow).AddYears(-1).ToString("yyyy-MM-dd");
+        var prevYear = DateTime.UtcNow.Year - 1;
+
+        // Daily records older than 1 year
+        var oldDailyIds = DailyRecords
+            .ToList()
+            .Where(r => String.Compare(r.Date, cutoff, StringComparison.Ordinal) < 0)
+            .Select(r => r.Id)
+            .ToList();
+        foreach (var id in oldDailyIds)
+            DailyRecords.Delete(r => r.Id == id);
+
+        // Hourly records older than 3 months (sufficient for pattern detection, 24x more rows than daily)
+        var hourlyCutoff = DateOnly.FromDateTime(DateTime.UtcNow).AddMonths(-3).ToString("yyyy-MM-dd");
+        var oldHourlyIds = HourlyRecords
+            .ToList()
+            .Where(r => String.Compare(r.Date, hourlyCutoff, StringComparison.Ordinal) < 0)
+            .Select(r => r.Id)
+            .ToList();
+        foreach (var id in oldHourlyIds)
+            HourlyRecords.Delete(r => r.Id == id);
+
+        // Weekly summaries older than 1 year
+        var oldWeeklyIds = WeeklyReports
+            .ToList()
+            .Where(r => String.Compare(r.PeriodEnd, cutoff, StringComparison.Ordinal) < 0)
+            .Select(r => r.Id)
+            .ToList();
+        foreach (var id in oldWeeklyIds)
+            WeeklyReports.Delete(r => r.Id == id);
+
+        // Monthly summaries older than 1 year
+        var oldMonthlyIds = MonthlyReports
+            .ToList()
+            .Where(r => String.Compare(r.PeriodEnd, cutoff, StringComparison.Ordinal) < 0)
+            .Select(r => r.Id)
+            .ToList();
+        foreach (var id in oldMonthlyIds)
+            MonthlyReports.Delete(r => r.Id == id);
+
+        // Yearly summaries — keep current and previous year only
+        YearlyReports.Delete(r => r.Year < prevYear);
+
+        // AI insight cache entries older than 1 year
+        var oldCacheIds = AiInsightCaches
+            .ToList()
+            .Where(c => String.Compare(c.CreatedAt, cutoff, StringComparison.Ordinal) < 0)
+            .Select(c => c.Id)
+            .ToList();
+        foreach (var id in oldCacheIds)
+            AiInsightCaches.Delete(c => c.Id == id);
+
+        Backup();
+        Console.WriteLine($"[Db] Cleanup: {oldDailyIds.Count} daily, {oldHourlyIds.Count} hourly, {oldWeeklyIds.Count} weekly, {oldMonthlyIds.Count} monthly, {oldCacheIds.Count} insight cache records deleted (cutoff {cutoff}).");
+    }
 }

csharp/App/Backend/Database/Read.cs

@@ -56,4 +56,104 @@ public static partial class Db
 
         return session;
     }
+
+    // ── Report Queries ────────────────────────────────────────────────
+
+    public static List<WeeklyReportSummary> GetWeeklyReports(Int64 installationId)
+        => WeeklyReports
+            .Where(r => r.InstallationId == installationId)
+            .OrderByDescending(r => r.PeriodStart)
+            .ToList();
+
+    public static List<WeeklyReportSummary> GetWeeklyReportsForMonth(Int64 installationId, Int32 year, Int32 month)
+    {
+        var monthStart = $"{year:D4}-{month:D2}-01";
+        var monthEnd   = month == 12 ? $"{year + 1:D4}-01-01" : $"{year:D4}-{month + 1:D2}-01";
+        return WeeklyReports
+            .Where(r => r.InstallationId == installationId)
+            .ToList()
+            .Where(r => String.Compare(r.PeriodStart, monthStart, StringComparison.Ordinal) >= 0
+                     && String.Compare(r.PeriodStart, monthEnd,   StringComparison.Ordinal) <  0)
+            .ToList();
+    }
+
+    public static List<MonthlyReportSummary> GetMonthlyReports(Int64 installationId)
+        => MonthlyReports
+            .Where(r => r.InstallationId == installationId)
+            .OrderByDescending(r => r.Year)
+            .ThenByDescending(r => r.Month)
+            .ToList();
+
+    public static List<MonthlyReportSummary> GetMonthlyReportsForYear(Int64 installationId, Int32 year)
+        => MonthlyReports
+            .Where(r => r.InstallationId == installationId && r.Year == year)
+            .ToList();
+
+    public static List<YearlyReportSummary> GetYearlyReports(Int64 installationId)
+        => YearlyReports
+            .Where(r => r.InstallationId == installationId)
+            .OrderByDescending(r => r.Year)
+            .ToList();
+
+    // ── DailyEnergyRecord Queries ──────────────────────────────────────
+
+    /// <summary>
+    /// Returns daily records for an installation within [from, to] inclusive, ordered by date.
+    /// </summary>
+    public static List<DailyEnergyRecord> GetDailyRecords(Int64 installationId, DateOnly from, DateOnly to)
+    {
+        var fromStr = from.ToString("yyyy-MM-dd");
+        var toStr   = to.ToString("yyyy-MM-dd");
+        return DailyRecords
+            .Where(r => r.InstallationId == installationId)
+            .ToList()
+            .Where(r => String.Compare(r.Date, fromStr, StringComparison.Ordinal) >= 0
+                     && String.Compare(r.Date, toStr,   StringComparison.Ordinal) <= 0)
+            .OrderBy(r => r.Date)
+            .ToList();
+    }
+
+    /// <summary>
+    /// Returns true if a daily record already exists for this installation+date (idempotency check).
+    /// </summary>
+    public static Boolean DailyRecordExists(Int64 installationId, String date)
+        => DailyRecords
+            .Any(r => r.InstallationId == installationId && r.Date == date);
+
+    // ── HourlyEnergyRecord Queries ─────────────────────────────────────
+
+    /// <summary>
+    /// Returns hourly records for an installation within [from, to] inclusive, ordered by date+hour.
+    /// </summary>
+    public static List<HourlyEnergyRecord> GetHourlyRecords(Int64 installationId, DateOnly from, DateOnly to)
+    {
+        var fromStr = from.ToString("yyyy-MM-dd");
+        var toStr   = to.ToString("yyyy-MM-dd");
+        return HourlyRecords
+            .Where(r => r.InstallationId == installationId)
+            .ToList()
+            .Where(r => String.Compare(r.Date, fromStr, StringComparison.Ordinal) >= 0
+                     && String.Compare(r.Date, toStr,   StringComparison.Ordinal) <= 0)
+            .OrderBy(r => r.Date).ThenBy(r => r.Hour)
+            .ToList();
+    }
+
+    /// <summary>
+    /// Returns true if an hourly record already exists for this installation+dateHour (idempotency check).
+    /// </summary>
+    public static Boolean HourlyRecordExists(Int64 installationId, String dateHour)
+        => HourlyRecords
+            .Any(r => r.InstallationId == installationId && r.DateHour == dateHour);
+
+    // ── AiInsightCache Queries ─────────────────────────────────────────
+
+    /// <summary>
+    /// Returns the cached AI insight text for (reportType, reportId, language), or null on miss.
+    /// </summary>
+    public static String? GetCachedInsight(String reportType, Int64 reportId, String language)
+        => AiInsightCaches
+            .FirstOrDefault(c => c.ReportType == reportType
+                              && c.ReportId   == reportId
+                              && c.Language   == language)
+            ?.InsightText;
 }

csharp/App/Backend/Program.cs

@@ -28,6 +28,8 @@ public static class Program
         LoadEnvFile();
         DiagnosticService.Initialize();
         AlarmReviewService.StartDailyScheduler();
+        // DailyIngestionService.StartScheduler();    // Phase 2: enable when S3 auto-push is ready
+        // ReportAggregationService.StartScheduler(); // Phase 2: enable when scheduler should auto-run monthly/yearly
         var builder = WebApplication.CreateBuilder(args);
         
         RabbitMqManager.InitializeEnvironment();

csharp/App/Backend/Services/DailyIngestionService.cs

@@ -0,0 +1,176 @@
+using InnovEnergy.App.Backend.Database;
+using InnovEnergy.App.Backend.DataTypes;
+
+namespace InnovEnergy.App.Backend.Services;
+
+/// <summary>
+/// Ingests daily energy totals from xlsx files into the DailyEnergyRecord SQLite table.
+/// This is the source-of-truth population step for the report pipeline.
+///
+/// Current data source: xlsx files placed in tmp_report/{installationId}.xlsx
+/// Future data source: S3 raw records (replace ExcelDataParser call with S3DailyExtractor)
+///
+/// Runs automatically at 01:00 UTC daily. Can also be triggered manually via the
+/// IngestDailyData API endpoint.
+/// </summary>
+public static class DailyIngestionService
+{
+    private static readonly String TmpReportDir =
+        Environment.CurrentDirectory + "/tmp_report/";
+
+    private static Timer? _dailyTimer;
+
+    /// <summary>
+    /// Starts the daily scheduler. Call once on app startup.
+    /// Ingests xlsx data at 01:00 UTC every day.
+    /// </summary>
+    public static void StartScheduler()
+    {
+        var now  = DateTime.UtcNow;
+        var next = now.Date.AddDays(1).AddHours(1); // 01:00 UTC tomorrow
+
+        _dailyTimer = new Timer(
+            _ =>
+            {
+                try
+                {
+                    IngestAllInstallationsAsync().GetAwaiter().GetResult();
+                }
+                catch (Exception ex)
+                {
+                    Console.Error.WriteLine($"[DailyIngestion] Scheduler error: {ex.Message}");
+                }
+            },
+            null, next - now, TimeSpan.FromDays(1));
+
+        Console.WriteLine($"[DailyIngestion] Scheduler started. Next run: {next:yyyy-MM-dd HH:mm} UTC");
+    }
+
+    /// <summary>
+    /// Ingests xlsx data for all SodioHome installations. Safe to call manually.
+    /// </summary>
+    public static async Task IngestAllInstallationsAsync()
+    {
+        Console.WriteLine($"[DailyIngestion] Starting ingestion for all SodioHome installations...");
+
+        var installations = Db.Installations
+            .Where(i => i.Product == (Int32)ProductType.SodioHome)
+            .ToList();
+
+        foreach (var installation in installations)
+        {
+            try
+            {
+                await IngestInstallationAsync(installation.Id);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[DailyIngestion] Failed for installation {installation.Id}: {ex.Message}");
+            }
+        }
+
+        Console.WriteLine($"[DailyIngestion] Ingestion complete.");
+    }
+
+    /// <summary>
+    /// Parses all xlsx files matching {installationId}*.xlsx in tmp_report/ and stores
+    /// any new days as DailyEnergyRecord rows. Supports multiple time-ranged files per
+    /// installation (e.g. 123_0203_0803.xlsx, 123_0901_1231.xlsx). Idempotent.
+    /// </summary>
+    public static async Task IngestInstallationAsync(Int64 installationId)
+    {
+        if (!Directory.Exists(TmpReportDir))
+        {
+            Console.WriteLine($"[DailyIngestion] tmp_report directory not found, skipping.");
+            return;
+        }
+
+        var xlsxFiles = Directory.GetFiles(TmpReportDir, $"{installationId}*.xlsx");
+        if (xlsxFiles.Length == 0)
+        {
+            Console.WriteLine($"[DailyIngestion] No xlsx found for installation {installationId}, skipping.");
+            return;
+        }
+
+        var newDailyCount  = 0;
+        var newHourlyCount = 0;
+        var totalParsed    = 0;
+
+        foreach (var xlsxPath in xlsxFiles.OrderBy(f => f))
+        {
+            // Ingest daily records
+            List<DailyEnergyData> days;
+            try
+            {
+                days = ExcelDataParser.Parse(xlsxPath);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[DailyIngestion] Failed to parse daily {Path.GetFileName(xlsxPath)}: {ex.Message}");
+                continue;
+            }
+
+            totalParsed += days.Count;
+
+            foreach (var day in days)
+            {
+                if (Db.DailyRecordExists(installationId, day.Date))
+                    continue;
+
+                Db.Create(new DailyEnergyRecord
+                {
+                    InstallationId    = installationId,
+                    Date              = day.Date,
+                    PvProduction      = day.PvProduction,
+                    LoadConsumption   = day.LoadConsumption,
+                    GridImport        = day.GridImport,
+                    GridExport        = day.GridExport,
+                    BatteryCharged    = day.BatteryCharged,
+                    BatteryDischarged = day.BatteryDischarged,
+                    CreatedAt         = DateTime.UtcNow.ToString("o"),
+                });
+                newDailyCount++;
+            }
+
+            // Ingest hourly records
+            List<HourlyEnergyData> hours;
+            try
+            {
+                hours = ExcelDataParser.ParseHourly(xlsxPath);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[DailyIngestion] Failed to parse hourly {Path.GetFileName(xlsxPath)}: {ex.Message}");
+                continue;
+            }
+
+            foreach (var hour in hours)
+            {
+                var dateHour = $"{hour.DateTime:yyyy-MM-dd HH}";
+                if (Db.HourlyRecordExists(installationId, dateHour))
+                    continue;
+
+                Db.Create(new HourlyEnergyRecord
+                {
+                    InstallationId       = installationId,
+                    Date                 = hour.DateTime.ToString("yyyy-MM-dd"),
+                    Hour                 = hour.Hour,
+                    DateHour             = dateHour,
+                    DayOfWeek            = hour.DayOfWeek,
+                    IsWeekend            = hour.IsWeekend,
+                    PvKwh                = hour.PvKwh,
+                    LoadKwh              = hour.LoadKwh,
+                    GridImportKwh        = hour.GridImportKwh,
+                    BatteryChargedKwh    = hour.BatteryChargedKwh,
+                    BatteryDischargedKwh = hour.BatteryDischargedKwh,
+                    BattSoC              = hour.BattSoC,
+                    CreatedAt            = DateTime.UtcNow.ToString("o"),
+                });
+                newHourlyCount++;
+            }
+        }
+
+        Console.WriteLine($"[DailyIngestion] Installation {installationId}: {newDailyCount} new day(s), {newHourlyCount} new hour(s) ingested ({totalParsed} days across {xlsxFiles.Length} file(s)).");
+        await Task.CompletedTask;
+    }
+}

csharp/App/Backend/Services/ReportAggregationService.cs

@@ -0,0 +1,773 @@
+using Flurl.Http;
+using InnovEnergy.App.Backend.Database;
+using InnovEnergy.App.Backend.DataTypes;
+using Newtonsoft.Json;
+
+namespace InnovEnergy.App.Backend.Services;
+
+public static class ReportAggregationService
+{
+    private static Timer? _monthEndTimer;
+    private static Timer? _yearEndTimer;
+    // private static Timer? _sundayReportTimer;
+
+    private const Double ElectricityPriceCHF = 0.39;
+    private static readonly String MistralUrl = "https://api.mistral.ai/v1/chat/completions";
+
+    // ── Scheduler ─────────────────────────────────────────────────────
+
+    public static void StartScheduler()
+    {
+        // ScheduleSundayWeeklyReport();
+        ScheduleMonthEndJob();
+        ScheduleYearEndJob();
+        Console.WriteLine("[ReportAggregation] Scheduler started.");
+    }
+
+    private static void ScheduleMonthEndJob()
+    {
+        // Run daily at 02:00, but only act on the 1st of the month
+        var now  = DateTime.Now;
+        var next = now.Date.AddHours(2);
+        if (now >= next) next = next.AddDays(1);
+
+        _monthEndTimer = new Timer(
+            _ =>
+            {
+                try
+                {
+                    if (DateTime.Now.Day == 1)
+                        RunMonthEndAggregation().GetAwaiter().GetResult();
+                }
+                catch (Exception ex)
+                {
+                    Console.Error.WriteLine($"[ReportAggregation] Month-end error: {ex.Message}");
+                }
+            },
+            null, next - now, TimeSpan.FromDays(1));
+
+        Console.WriteLine($"[ReportAggregation] Month-end timer scheduled (daily 02:00, acts on 1st). Next check: {next:yyyy-MM-dd HH:mm}");
+    }
+
+    private static void ScheduleYearEndJob()
+    {
+        // Run daily at 03:00, but only act on Jan 2nd
+        var now  = DateTime.Now;
+        var next = now.Date.AddHours(3);
+        if (now >= next) next = next.AddDays(1);
+
+        _yearEndTimer = new Timer(
+            _ =>
+            {
+                try
+                {
+                    if (DateTime.Now.Month == 1 && DateTime.Now.Day == 2)
+                        RunYearEndAggregation().GetAwaiter().GetResult();
+                }
+                catch (Exception ex)
+                {
+                    Console.Error.WriteLine($"[ReportAggregation] Year-end error: {ex.Message}");
+                }
+            },
+            null, next - now, TimeSpan.FromDays(1));
+
+        Console.WriteLine($"[ReportAggregation] Year-end timer scheduled (daily 03:00, acts on Jan 2). Next check: {next:yyyy-MM-dd HH:mm}");
+    }
+
+    // ── Sunday Weekly Report Automation ─────────────────────────────
+    // Generates weekly reports (Sunday–Saturday) for all SodiStoreHome
+    // installations every Sunday at 06:00, saves summary to DB, and
+    // emails the report to all users who have access to the installation.
+    //
+    // TODO: uncomment ScheduleSundayWeeklyReport() in StartScheduler() to enable.
+
+    // private static void ScheduleSundayWeeklyReport()
+    // {
+    //     // Calculate delay until next Sunday 06:00
+    //     var now        = DateTime.Now;
+    //     var daysUntil  = ((int)DayOfWeek.Sunday - (int)now.DayOfWeek + 7) % 7;
+    //     var nextSunday = now.Date.AddDays(daysUntil == 0 && now.Hour >= 6 ? 7 : daysUntil).AddHours(6);
+    //
+    //     _sundayReportTimer = new Timer(
+    //         _ =>
+    //         {
+    //             try
+    //             {
+    //                 if (DateTime.Now.DayOfWeek == DayOfWeek.Sunday)
+    //                     RunSundayWeeklyReports().GetAwaiter().GetResult();
+    //             }
+    //             catch (Exception ex)
+    //             {
+    //                 Console.Error.WriteLine($"[ReportAggregation] Sunday report error: {ex.Message}");
+    //             }
+    //         },
+    //         null, nextSunday - now, TimeSpan.FromDays(7));
+    //
+    //     Console.WriteLine($"[ReportAggregation] Sunday weekly report scheduled. Next run: {nextSunday:yyyy-MM-dd HH:mm}");
+    // }
+    //
+    // private static async Task RunSundayWeeklyReports()
+    // {
+    //     Console.WriteLine("[ReportAggregation] Running Sunday weekly report generation...");
+    //
+    //     // Find all SodiStoreHome installations
+    //     var installations = Db.Installations
+    //         .Where(i => i.Product == (int)ProductType.SodioHome)
+    //         .ToList();
+    //
+    //     foreach (var installation in installations)
+    //     {
+    //         try
+    //         {
+    //             // Generate the weekly report (covers last Sunday–Saturday)
+    //             var report = await WeeklyReportService.GenerateReportAsync(
+    //                 installation.Id, installation.InstallationName, "en");
+    //
+    //             // Save summary to DB for future monthly aggregation
+    //             SaveWeeklySummary(installation.Id, report);
+    //
+    //             // Email the report to all users who have access to this installation
+    //             var userIds = Db.InstallationAccess
+    //                 .Where(a => a.InstallationId == installation.Id)
+    //                 .Select(a => a.UserId)
+    //                 .ToList();
+    //
+    //             foreach (var userId in userIds)
+    //             {
+    //                 var user = Db.GetUserById(userId);
+    //                 if (user == null || String.IsNullOrWhiteSpace(user.Email))
+    //                     continue;
+    //
+    //                 try
+    //                 {
+    //                     var lang = user.Language ?? "en";
+    //                     // Regenerate with user's language if different from "en"
+    //                     var localizedReport = lang == "en"
+    //                         ? report
+    //                         : await WeeklyReportService.GenerateReportAsync(
+    //                             installation.Id, installation.InstallationName, lang);
+    //
+    //                     await ReportEmailService.SendReportEmailAsync(localizedReport, user.Email, lang);
+    //                     Console.WriteLine($"[ReportAggregation] Weekly report emailed to {user.Email} for installation {installation.Id}");
+    //                 }
+    //                 catch (Exception emailEx)
+    //                 {
+    //                     Console.Error.WriteLine($"[ReportAggregation] Failed to email {user.Email}: {emailEx.Message}");
+    //                 }
+    //             }
+    //         }
+    //         catch (Exception ex)
+    //         {
+    //             Console.Error.WriteLine($"[ReportAggregation] Failed weekly report for installation {installation.Id}: {ex.Message}");
+    //         }
+    //     }
+    //
+    //     Console.WriteLine("[ReportAggregation] Sunday weekly report generation complete.");
+    // }
+
+    // ── Save Weekly Summary ───────────────────────────────────────────
+
+    public static void SaveWeeklySummary(Int64 installationId, WeeklyReportResponse report, String language = "en")
+    {
+        try
+        {
+            // Remove any existing weekly records whose date range overlaps with this report.
+            // Two periods overlap when: existingStart < newEnd AND newStart < existingEnd.
+            // This prevents double-counting when the same days appear in different report windows
+            // (e.g., report for days 1-7, then later 2-8 — the old 1-7 record is removed).
+            var overlapping = Db.WeeklyReports
+                .Where(r => r.InstallationId == installationId)
+                .ToList()
+                .Where(r => String.Compare(r.PeriodStart, report.PeriodEnd,   StringComparison.Ordinal) < 0
+                         && String.Compare(report.PeriodStart, r.PeriodEnd, StringComparison.Ordinal) < 0)
+                .ToList();
+
+            foreach (var old in overlapping)
+                Db.WeeklyReports.Delete(r => r.Id == old.Id);
+
+            var summary = new WeeklyReportSummary
+            {
+                InstallationId          = installationId,
+                PeriodStart             = report.PeriodStart,
+                PeriodEnd               = report.PeriodEnd,
+                TotalPvProduction       = report.CurrentWeek.TotalPvProduction,
+                TotalConsumption        = report.CurrentWeek.TotalConsumption,
+                TotalGridImport         = report.CurrentWeek.TotalGridImport,
+                TotalGridExport         = report.CurrentWeek.TotalGridExport,
+                TotalBatteryCharged     = report.CurrentWeek.TotalBatteryCharged,
+                TotalBatteryDischarged  = report.CurrentWeek.TotalBatteryDischarged,
+                TotalEnergySaved        = report.TotalEnergySaved,
+                TotalSavingsCHF         = report.TotalSavingsCHF,
+                SelfSufficiencyPercent  = report.SelfSufficiencyPercent,
+                SelfConsumptionPercent  = report.SelfConsumptionPercent,
+                BatteryEfficiencyPercent = report.BatteryEfficiencyPercent,
+                GridDependencyPercent   = report.GridDependencyPercent,
+                PeakLoadHour            = report.Behavior?.PeakLoadHour ?? 0,
+                PeakSolarHour           = report.Behavior?.PeakSolarHour ?? 0,
+                WeekdayAvgDailyLoad     = report.Behavior?.WeekdayAvgDailyLoad ?? 0,
+                WeekendAvgDailyLoad     = report.Behavior?.WeekendAvgDailyLoad ?? 0,
+                AiInsight               = report.AiInsight,
+                CreatedAt               = DateTime.UtcNow.ToString("o"),
+            };
+
+            Db.Create(summary);
+
+            // Seed AiInsightCache so historical reads for this language are free
+            if (!String.IsNullOrEmpty(summary.AiInsight))
+                Db.Create(new AiInsightCache
+                {
+                    ReportType  = "weekly",
+                    ReportId    = summary.Id,
+                    Language    = language,
+                    InsightText = summary.AiInsight,
+                    CreatedAt   = summary.CreatedAt,
+                });
+
+            Console.WriteLine($"[ReportAggregation] Saved weekly summary for installation {installationId}, period {report.PeriodStart}–{report.PeriodEnd} (replaced {overlapping.Count} overlapping record(s))");
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[ReportAggregation] Failed to save weekly summary for installation {installationId}: {ex.Message}");
+        }
+    }
+
+    // ── Pending Aggregation Queries ─────────────────────────────────
+
+    /// <summary>
+    /// Returns months that have weekly data but no monthly report yet.
+    /// Each entry: { Year, Month, WeekCount }.
+    /// </summary>
+    public static List<PendingMonth> GetPendingMonthlyAggregations(Int64 installationId)
+    {
+        var weeklies = Db.GetWeeklyReports(installationId);
+        var existingMonths = Db.GetMonthlyReports(installationId)
+            .Select(m => (m.Year, m.Month))
+            .ToHashSet();
+
+        return weeklies
+            .GroupBy(w =>
+            {
+                var date = DateTime.Parse(w.PeriodStart);
+                return (Year: date.Year, Month: date.Month);
+            })
+            .Where(g => !existingMonths.Contains(g.Key))
+            .Select(g => new PendingMonth { Year = g.Key.Year, Month = g.Key.Month, WeekCount = g.Count() })
+            .OrderByDescending(p => p.Year).ThenByDescending(p => p.Month)
+            .ToList();
+    }
+
+    /// <summary>
+    /// Returns years that have monthly data but no yearly report yet.
+    /// Each entry: { Year, MonthCount }.
+    /// </summary>
+    public static List<PendingYear> GetPendingYearlyAggregations(Int64 installationId)
+    {
+        var monthlies = Db.GetMonthlyReports(installationId);
+        var existingYears = Db.GetYearlyReports(installationId)
+            .Select(y => y.Year)
+            .ToHashSet();
+
+        return monthlies
+            .GroupBy(m => m.Year)
+            .Where(g => !existingYears.Contains(g.Key))
+            .Select(g => new PendingYear { Year = g.Key, MonthCount = g.Count() })
+            .OrderByDescending(p => p.Year)
+            .ToList();
+    }
+
+    // ── Month-End Aggregation ─────────────────────────────────────────
+
+    /// <summary>
+    /// Trigger monthly aggregation for a specific installation and month.
+    /// Re-generates if a monthly report already exists. Weekly records are kept.
+    /// Returns the number of weekly records aggregated (0 = no data).
+    /// </summary>
+    public static async Task<Int32> TriggerMonthlyAggregationAsync(Int64 installationId, Int32 year, Int32 month, String language = "en")
+    {
+        var first = new DateOnly(year, month, 1);
+        var last  = first.AddMonths(1).AddDays(-1);
+        var days  = Db.GetDailyRecords(installationId, first, last);
+        if (days.Count == 0)
+            return 0;
+
+        await AggregateMonthForInstallation(installationId, year, month, language);
+        return days.Count;
+    }
+
+    /// <summary>
+    /// Trigger yearly aggregation for a specific installation and year.
+    /// Re-generates if a yearly report already exists. Monthly records are kept.
+    /// Returns the number of monthly records aggregated (0 = no data).
+    /// </summary>
+    public static async Task<Int32> TriggerYearlyAggregationAsync(Int64 installationId, Int32 year, String language = "en")
+    {
+        var monthlies = Db.GetMonthlyReportsForYear(installationId, year);
+        if (monthlies.Count == 0)
+            return 0;
+
+        await AggregateYearForInstallation(installationId, year, language);
+        return monthlies.Count;
+    }
+
+    private static async Task RunMonthEndAggregation()
+    {
+        var previousMonth = DateTime.Now.AddMonths(-1);
+        var year  = previousMonth.Year;
+        var month = previousMonth.Month;
+        var first = new DateOnly(year, month, 1);
+        var last  = first.AddMonths(1).AddDays(-1);
+
+        Console.WriteLine($"[ReportAggregation] Running month-end aggregation for {year}-{month:D2}...");
+
+        // Find all installations that have daily records for the previous month
+        var installationIds = Db.DailyRecords
+            .Where(r => String.Compare(r.Date, first.ToString("yyyy-MM-dd"), StringComparison.Ordinal) >= 0
+                     && String.Compare(r.Date, last.ToString("yyyy-MM-dd"),  StringComparison.Ordinal) <= 0)
+            .Select(r => r.InstallationId)
+            .ToList()
+            .Distinct()
+            .ToList();
+
+        foreach (var installationId in installationIds)
+        {
+            try
+            {
+                await AggregateMonthForInstallation(installationId, year, month);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[ReportAggregation] Month aggregation failed for installation {installationId}: {ex.Message}");
+            }
+        }
+    }
+
+    private static async Task AggregateMonthForInstallation(Int64 installationId, Int32 year, Int32 month, String language = "en")
+    {
+        // Compute from daily records for the full calendar month
+        var first = new DateOnly(year, month, 1);
+        var last  = first.AddMonths(1).AddDays(-1);
+        var days  = Db.GetDailyRecords(installationId, first, last);
+        if (days.Count == 0)
+            return;
+
+        // If monthly report already exists, delete it so we can re-generate
+        Db.DeleteMonthlyReport(installationId, year, month);
+
+        // Sum energy totals directly from daily records
+        var totalPv       = Math.Round(days.Sum(d => d.PvProduction), 1);
+        var totalConsump  = Math.Round(days.Sum(d => d.LoadConsumption), 1);
+        var totalGridIn   = Math.Round(days.Sum(d => d.GridImport), 1);
+        var totalGridOut  = Math.Round(days.Sum(d => d.GridExport), 1);
+        var totalBattChg  = Math.Round(days.Sum(d => d.BatteryCharged), 1);
+        var totalBattDis  = Math.Round(days.Sum(d => d.BatteryDischarged), 1);
+
+        // Re-derive ratios
+        var energySaved     = Math.Round(totalConsump - totalGridIn, 1);
+        var savingsCHF      = Math.Round(energySaved * ElectricityPriceCHF, 0);
+        var selfSufficiency = totalConsump > 0 ? Math.Round((totalConsump - totalGridIn) / totalConsump * 100, 1) : 0;
+        var selfConsumption = totalPv > 0 ? Math.Round((totalPv - totalGridOut) / totalPv * 100, 1) : 0;
+        var batteryEff      = totalBattChg > 0 ? Math.Round(totalBattDis / totalBattChg * 100, 1) : 0;
+        var gridDependency  = totalConsump > 0 ? Math.Round(totalGridIn / totalConsump * 100, 1) : 0;
+
+        // Get installation name for AI insight
+        var installation     = Db.GetInstallationById(installationId);
+        var installationName = installation?.InstallationName ?? $"Installation {installationId}";
+        var monthName        = new DateTime(year, month, 1).ToString("MMMM yyyy");
+
+        var aiInsight = await GenerateMonthlyAiInsightAsync(
+            installationName, monthName, days.Count,
+            totalPv, totalConsump, totalGridIn, totalGridOut,
+            totalBattChg, totalBattDis, energySaved, savingsCHF,
+            selfSufficiency, batteryEff, language);
+
+        var monthlySummary = new MonthlyReportSummary
+        {
+            InstallationId           = installationId,
+            Year                     = year,
+            Month                    = month,
+            PeriodStart              = first.ToString("yyyy-MM-dd"),
+            PeriodEnd                = last.ToString("yyyy-MM-dd"),
+            TotalPvProduction        = totalPv,
+            TotalConsumption         = totalConsump,
+            TotalGridImport          = totalGridIn,
+            TotalGridExport          = totalGridOut,
+            TotalBatteryCharged      = totalBattChg,
+            TotalBatteryDischarged   = totalBattDis,
+            TotalEnergySaved         = energySaved,
+            TotalSavingsCHF          = savingsCHF,
+            SelfSufficiencyPercent   = selfSufficiency,
+            SelfConsumptionPercent   = selfConsumption,
+            BatteryEfficiencyPercent = batteryEff,
+            GridDependencyPercent    = gridDependency,
+            AvgPeakLoadHour          = 0,   // Not available without hourly data; Phase 3 will add
+            AvgPeakSolarHour         = 0,
+            AvgWeekdayDailyLoad      = 0,
+            AvgWeekendDailyLoad      = 0,
+            WeekCount                = days.Count,  // repurposed as day count
+            AiInsight                = aiInsight,
+            CreatedAt                = DateTime.UtcNow.ToString("o"),
+        };
+
+        Db.Create(monthlySummary);
+
+        // Seed AiInsightCache so the generating language is pre-cached
+        if (!String.IsNullOrEmpty(monthlySummary.AiInsight))
+            Db.Create(new AiInsightCache
+            {
+                ReportType  = "monthly",
+                ReportId    = monthlySummary.Id,
+                Language    = language,
+                InsightText = monthlySummary.AiInsight,
+                CreatedAt   = monthlySummary.CreatedAt,
+            });
+
+        Console.WriteLine($"[ReportAggregation] Monthly report created for installation {installationId}, {year}-{month:D2} ({days.Count} days, {first}–{last}).");
+    }
+
+    // ── Year-End Aggregation ──────────────────────────────────────────
+
+    private static async Task RunYearEndAggregation()
+    {
+        var previousYear = DateTime.Now.Year - 1;
+
+        Console.WriteLine($"[ReportAggregation] Running year-end aggregation for {previousYear}...");
+
+        var installationIds = Db.MonthlyReports
+            .Where(r => r.Year == previousYear)
+            .Select(r => r.InstallationId)
+            .ToList()
+            .Distinct()
+            .ToList();
+
+        foreach (var installationId in installationIds)
+        {
+            try
+            {
+                await AggregateYearForInstallation(installationId, previousYear);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[ReportAggregation] Year aggregation failed for installation {installationId}: {ex.Message}");
+            }
+        }
+
+        // Time-based cleanup: delete records older than 1 year, runs after yearly report is created
+        CleanupOldRecords();
+    }
+
+    private static async Task AggregateYearForInstallation(Int64 installationId, Int32 year, String language = "en")
+    {
+        var monthlies = Db.GetMonthlyReportsForYear(installationId, year);
+        if (monthlies.Count == 0)
+            return;
+
+        // If yearly report already exists, delete it so we can re-generate with latest monthly data.
+        Db.DeleteYearlyReport(installationId, year);
+
+        // Sum energy totals
+        var totalPv       = Math.Round(monthlies.Sum(m => m.TotalPvProduction), 1);
+        var totalConsump  = Math.Round(monthlies.Sum(m => m.TotalConsumption), 1);
+        var totalGridIn   = Math.Round(monthlies.Sum(m => m.TotalGridImport), 1);
+        var totalGridOut  = Math.Round(monthlies.Sum(m => m.TotalGridExport), 1);
+        var totalBattChg  = Math.Round(monthlies.Sum(m => m.TotalBatteryCharged), 1);
+        var totalBattDis  = Math.Round(monthlies.Sum(m => m.TotalBatteryDischarged), 1);
+
+        // Re-derive ratios
+        var energySaved     = Math.Round(totalConsump - totalGridIn, 1);
+        var savingsCHF      = Math.Round(energySaved * ElectricityPriceCHF, 0);
+        var selfSufficiency = totalConsump > 0 ? Math.Round((totalConsump - totalGridIn) / totalConsump * 100, 1) : 0;
+        var selfConsumption = totalPv > 0 ? Math.Round((totalPv - totalGridOut) / totalPv * 100, 1) : 0;
+        var batteryEff      = totalBattChg > 0 ? Math.Round(totalBattDis / totalBattChg * 100, 1) : 0;
+        var gridDependency  = totalConsump > 0 ? Math.Round(totalGridIn / totalConsump * 100, 1) : 0;
+
+        var avgPeakLoad    = (Int32)Math.Round(monthlies.Average(m => m.AvgPeakLoadHour));
+        var avgPeakSolar   = (Int32)Math.Round(monthlies.Average(m => m.AvgPeakSolarHour));
+        var avgWeekdayLoad = Math.Round(monthlies.Average(m => m.AvgWeekdayDailyLoad), 1);
+        var avgWeekendLoad = Math.Round(monthlies.Average(m => m.AvgWeekendDailyLoad), 1);
+
+        var installation     = Db.GetInstallationById(installationId);
+        var installationName = installation?.InstallationName ?? $"Installation {installationId}";
+
+        var aiInsight = await GenerateYearlyAiInsightAsync(
+            installationName, year, monthlies.Count,
+            totalPv, totalConsump, totalGridIn, totalGridOut,
+            totalBattChg, totalBattDis, energySaved, savingsCHF,
+            selfSufficiency, batteryEff, language);
+
+        var yearlySummary = new YearlyReportSummary
+        {
+            InstallationId          = installationId,
+            Year                    = year,
+            PeriodStart             = monthlies.Min(m => m.PeriodStart),
+            PeriodEnd               = monthlies.Max(m => m.PeriodEnd),
+            TotalPvProduction       = totalPv,
+            TotalConsumption        = totalConsump,
+            TotalGridImport         = totalGridIn,
+            TotalGridExport         = totalGridOut,
+            TotalBatteryCharged     = totalBattChg,
+            TotalBatteryDischarged  = totalBattDis,
+            TotalEnergySaved        = energySaved,
+            TotalSavingsCHF         = savingsCHF,
+            SelfSufficiencyPercent  = selfSufficiency,
+            SelfConsumptionPercent  = selfConsumption,
+            BatteryEfficiencyPercent = batteryEff,
+            GridDependencyPercent   = gridDependency,
+            AvgPeakLoadHour         = avgPeakLoad,
+            AvgPeakSolarHour        = avgPeakSolar,
+            AvgWeekdayDailyLoad     = avgWeekdayLoad,
+            AvgWeekendDailyLoad     = avgWeekendLoad,
+            MonthCount              = monthlies.Count,
+            AiInsight               = aiInsight,
+            CreatedAt               = DateTime.UtcNow.ToString("o"),
+        };
+
+        Db.Create(yearlySummary);
+
+        // Seed AiInsightCache so the generating language is pre-cached
+        if (!String.IsNullOrEmpty(yearlySummary.AiInsight))
+            Db.Create(new AiInsightCache
+            {
+                ReportType  = "yearly",
+                ReportId    = yearlySummary.Id,
+                Language    = language,
+                InsightText = yearlySummary.AiInsight,
+                CreatedAt   = yearlySummary.CreatedAt,
+            });
+
+        Console.WriteLine($"[ReportAggregation] Yearly report created for installation {installationId}, {year} ({monthlies.Count} months aggregated).");
+    }
+
+    // ── AI Insight Cache ──────────────────────────────────────────────
+
+    /// <summary>
+    /// Returns cached AI insight for (reportType, reportId, language).
+    /// On cache miss: calls generate(), stores the result, and returns it.
+    /// This is the single entry-point for all per-language insight reads.
+    /// </summary>
+    public static async Task<String> GetOrGenerateInsightAsync(
+        String reportType, Int64 reportId, String language, Func<Task<String>> generate)
+    {
+        var cached = Db.GetCachedInsight(reportType, reportId, language);
+        if (!String.IsNullOrEmpty(cached))
+            return cached;
+
+        var insight = await generate();
+        Db.Create(new AiInsightCache
+        {
+            ReportType  = reportType,
+            ReportId    = reportId,
+            Language    = language,
+            InsightText = insight,
+            CreatedAt   = DateTime.UtcNow.ToString("o"),
+        });
+        return insight;
+    }
+
+    /// <summary>Cached-or-generated AI insight for a stored WeeklyReportSummary.</summary>
+    public static Task<String> GetOrGenerateWeeklyInsightAsync(
+        WeeklyReportSummary report, String language)
+    {
+        var installationName = Db.GetInstallationById(report.InstallationId)?.InstallationName
+                               ?? $"Installation {report.InstallationId}";
+        return GetOrGenerateInsightAsync("weekly", report.Id, language,
+            () => GenerateWeeklySummaryAiInsightAsync(report, installationName, language));
+    }
+
+    /// <summary>Cached-or-generated AI insight for a stored MonthlyReportSummary.</summary>
+    public static Task<String> GetOrGenerateMonthlyInsightAsync(
+        MonthlyReportSummary report, String language)
+    {
+        var installationName = Db.GetInstallationById(report.InstallationId)?.InstallationName
+                               ?? $"Installation {report.InstallationId}";
+        var monthName = new DateTime(report.Year, report.Month, 1).ToString("MMMM yyyy");
+        return GetOrGenerateInsightAsync("monthly", report.Id, language,
+            () => GenerateMonthlyAiInsightAsync(
+                installationName, monthName, report.WeekCount,
+                report.TotalPvProduction, report.TotalConsumption,
+                report.TotalGridImport, report.TotalGridExport,
+                report.TotalBatteryCharged, report.TotalBatteryDischarged,
+                report.TotalEnergySaved, report.TotalSavingsCHF,
+                report.SelfSufficiencyPercent, report.BatteryEfficiencyPercent, language));
+    }
+
+    /// <summary>Cached-or-generated AI insight for a stored YearlyReportSummary.</summary>
+    public static Task<String> GetOrGenerateYearlyInsightAsync(
+        YearlyReportSummary report, String language)
+    {
+        var installationName = Db.GetInstallationById(report.InstallationId)?.InstallationName
+                               ?? $"Installation {report.InstallationId}";
+        return GetOrGenerateInsightAsync("yearly", report.Id, language,
+            () => GenerateYearlyAiInsightAsync(
+                installationName, report.Year, report.MonthCount,
+                report.TotalPvProduction, report.TotalConsumption,
+                report.TotalGridImport, report.TotalGridExport,
+                report.TotalBatteryCharged, report.TotalBatteryDischarged,
+                report.TotalEnergySaved, report.TotalSavingsCHF,
+                report.SelfSufficiencyPercent, report.BatteryEfficiencyPercent, language));
+    }
+
+    // ── Time-Based Cleanup ────────────────────────────────────────────
+
+    /// <summary>
+    /// Deletes records older than 1 year. Called annually on Jan 2 after
+    /// yearly reports are created, so monthly summaries are still available
+    /// when yearly is computed.
+    /// </summary>
+    private static void CleanupOldRecords()
+    {
+        try
+        {
+            Db.CleanupOldData();
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[ReportAggregation] Cleanup error: {ex.Message}");
+        }
+    }
+
+    // ── AI Insight Generation ─────────────────────────────────────────
+
+    /// <summary>
+    /// Simplified weekly AI insight generated from the stored WeeklyReportSummary numerical fields.
+    /// Used for historical weeks where the original hourly data is no longer available.
+    /// </summary>
+    private static async Task<String> GenerateWeeklySummaryAiInsightAsync(
+        WeeklyReportSummary summary, String installationName, String language = "en")
+    {
+        var apiKey = Environment.GetEnvironmentVariable("MISTRAL_API_KEY");
+        if (String.IsNullOrWhiteSpace(apiKey))
+            return "AI insight unavailable (API key not configured).";
+
+        var langName = GetLanguageName(language);
+        var prompt   = $@"You are an energy advisor for a sodistore home installation: ""{installationName}"".
+
+Write a concise weekly performance summary in {langName} (4 bullet points starting with ""- "").
+
+WEEKLY FACTS for {summary.PeriodStart} to {summary.PeriodEnd}:
+- PV production: {summary.TotalPvProduction:F1} kWh | Consumption: {summary.TotalConsumption:F1} kWh
+- Grid import: {summary.TotalGridImport:F1} kWh | Grid export: {summary.TotalGridExport:F1} kWh
+- Battery: {summary.TotalBatteryCharged:F1} kWh charged, {summary.TotalBatteryDischarged:F1} kWh discharged
+- Energy saved: {summary.TotalEnergySaved:F1} kWh = ~{summary.TotalSavingsCHF:F0} CHF
+- Self-sufficiency: {summary.SelfSufficiencyPercent:F1}% | Grid dependency: {summary.GridDependencyPercent:F1}%
+
+Rules: Write in {langName}. Write for a homeowner. No asterisks or formatting marks.
+Exactly 4 bullet points. Each starts with ""- Title: description"" format.";
+
+        return await CallMistralAsync(apiKey, prompt);
+    }
+
+    private static String GetLanguageName(String code) => code switch
+    {
+        "de" => "German",
+        "fr" => "French",
+        "it" => "Italian",
+        _    => "English"
+    };
+
+    private static async Task<String> GenerateMonthlyAiInsightAsync(
+        String installationName, String monthName, Int32 weekCount,
+        Double totalPv, Double totalConsump, Double totalGridIn, Double totalGridOut,
+        Double totalBattChg, Double totalBattDis,
+        Double energySaved, Double savingsCHF,
+        Double selfSufficiency, Double batteryEff,
+        String language = "en")
+    {
+        var apiKey = Environment.GetEnvironmentVariable("MISTRAL_API_KEY");
+        if (String.IsNullOrWhiteSpace(apiKey))
+            return "AI insight unavailable (API key not configured).";
+
+        var langName = GetLanguageName(language);
+
+        // Determine which metric is weakest so the tip can be targeted
+        var weakMetric = batteryEff < 80 ? "battery" : selfSufficiency < 40 ? "self-sufficiency" : "general";
+
+        var prompt = $@"You are an energy advisor for a sodistore home installation: ""{installationName}"".
+
+Write a concise monthly performance summary in {langName} (4 bullet points, plain text, no markdown).
+
+MONTHLY FACTS for {monthName} ({weekCount} days of data):
+- PV production: {totalPv:F1} kWh
+- Total consumption: {totalConsump:F1} kWh
+- Self-sufficiency: {selfSufficiency:F1}% (share of energy covered by solar, without drawing from grid)
+- Battery: {totalBattChg:F1} kWh charged, {totalBattDis:F1} kWh discharged, efficiency {batteryEff:F1}%
+- Energy saved: {energySaved:F1} kWh = ~{savingsCHF:F0} CHF saved (at {ElectricityPriceCHF} CHF/kWh)
+
+INSTRUCTIONS:
+1. Savings: state exactly how much energy and money was saved this month. Positive framing.
+2. Solar performance: how much the solar system produced and what self-sufficiency % means for the homeowner (e.g. ""Your solar system covered X% of your home's energy needs""). Do NOT mention battery here. Do NOT mention raw grid import kWh.
+3. Battery: comment on battery utilization and efficiency. If efficiency < 80%, note it may need attention.
+4. Tip: one specific actionable suggestion based on the weakest metric: {weakMetric}. If general, suggest the most impactful habit change based on the numbers above.
+
+Rules: Write in {langName}. Write for a homeowner, not a technician. No asterisks or formatting marks. No closing remarks. Exactly 4 bullet points starting with ""- "". Each bullet must have a short title followed by colon then description.";
+
+        return await CallMistralAsync(apiKey, prompt);
+    }
+
+    private static async Task<String> GenerateYearlyAiInsightAsync(
+        String installationName, Int32 year, Int32 monthCount,
+        Double totalPv, Double totalConsump, Double totalGridIn, Double totalGridOut,
+        Double totalBattChg, Double totalBattDis,
+        Double energySaved, Double savingsCHF,
+        Double selfSufficiency, Double batteryEff,
+        String language = "en")
+    {
+        var apiKey = Environment.GetEnvironmentVariable("MISTRAL_API_KEY");
+        if (String.IsNullOrWhiteSpace(apiKey))
+            return "AI insight unavailable (API key not configured).";
+
+        var langName = GetLanguageName(language);
+        var prompt = $@"You are an energy advisor for a sodistore home installation: ""{installationName}"".
+
+Write a concise annual performance summary in {langName} (4 bullet points, plain text, no markdown).
+
+ANNUAL FACTS for {year} ({monthCount} months of data):
+- Total PV production: {totalPv:F1} kWh
+- Total consumption: {totalConsump:F1} kWh
+- Total grid import: {totalGridIn:F1} kWh, export: {totalGridOut:F1} kWh
+- Battery: {totalBattChg:F1} kWh charged, {totalBattDis:F1} kWh discharged
+- Energy saved from grid: {energySaved:F1} kWh = ~{savingsCHF:F0} CHF (at {ElectricityPriceCHF} CHF/kWh)
+- Self-sufficiency: {selfSufficiency:F1}%
+- Battery efficiency: {batteryEff:F1}%
+
+INSTRUCTIONS:
+1. Annual savings highlight: total energy and money saved for the year. Use the exact numbers provided.
+2. System performance: comment on PV production and battery health indicators.
+3. Year-over-year readiness: note any trends or areas of improvement.
+4. Looking ahead: one strategic recommendation for the coming year.
+
+Rules: Write in {langName}. Write for a homeowner. No asterisks or formatting marks. No closing remarks. Exactly 4 bullet points starting with ""- "". Each bullet must have a short title followed by colon then description.";
+
+        return await CallMistralAsync(apiKey, prompt);
+    }
+
+    private static async Task<String> CallMistralAsync(String apiKey, String prompt)
+    {
+        try
+        {
+            var requestBody = new
+            {
+                model       = "mistral-small-latest",
+                messages    = new[] { new { role = "user", content = prompt } },
+                max_tokens  = 400,
+                temperature = 0.3
+            };
+
+            var responseText = await MistralUrl
+                .WithHeader("Authorization", $"Bearer {apiKey}")
+                .PostJsonAsync(requestBody)
+                .ReceiveString();
+
+            var envelope = JsonConvert.DeserializeObject<dynamic>(responseText);
+            var content  = (String?)envelope?.choices?[0]?.message?.content;
+
+            if (!String.IsNullOrWhiteSpace(content))
+                return content.Trim();
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[ReportAggregation] Mistral error: {ex.Message}");
+        }
+
+        return "AI insight could not be generated at this time.";
+    }
+}

csharp/App/Backend/Services/ReportEmailService.cs

@@ -217,10 +217,10 @@ public static class ReportEmailService
         var cur  = r.CurrentWeek;
         var prev = r.PreviousWeek;
 
-        // Parse AI insight into <li> bullet points (split on newlines, strip leading "- " or "1. ")
+        // Parse AI insight into <li> bullet points (split on newlines, strip leading "- " or "1. ", strip ** markdown)
         var insightLines = r.AiInsight
             .Split('\n', StringSplitOptions.RemoveEmptyEntries)
-            .Select(l => System.Text.RegularExpressions.Regex.Replace(l.Trim(), @"^[\d]+[.)]\s*|^[-*]\s*", ""))
+            .Select(l => System.Text.RegularExpressions.Regex.Replace(l.Trim(), @"^[\d]+[.)]\s*|^[-*]\s*", "").Replace("**", ""))
             .Where(l => l.Length > 0)
             .ToList();
 
@@ -443,4 +443,230 @@ public static class ReportEmailService
 
     private static string ChangeColor(double pct) =>
         pct > 0 ? "#27ae60" : pct < 0 ? "#e74c3c" : "#888";
+
+    // ── Monthly / Yearly Report Emails ────────────────────────────────────
+
+    private static readonly string[] MonthNamesEn = { "", "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" };
+    private static readonly string[] MonthNamesDe = { "", "Januar", "Februar", "März", "April", "Mai", "Juni", "Juli", "August", "September", "Oktober", "November", "Dezember" };
+    private static readonly string[] MonthNamesFr = { "", "Janvier", "Février", "Mars", "Avril", "Mai", "Juin", "Juillet", "Août", "Septembre", "Octobre", "Novembre", "Décembre" };
+    private static readonly string[] MonthNamesIt = { "", "Gennaio", "Febbraio", "Marzo", "Aprile", "Maggio", "Giugno", "Luglio", "Agosto", "Settembre", "Ottobre", "Novembre", "Dicembre" };
+
+    public static async Task SendMonthlyReportEmailAsync(
+        MonthlyReportSummary report,
+        string installationName,
+        string recipientEmail,
+        string language = "en")
+    {
+        var monthNames = language switch { "de" => MonthNamesDe, "fr" => MonthNamesFr, "it" => MonthNamesIt, _ => MonthNamesEn };
+        var monthName  = report.Month >= 1 && report.Month <= 12 ? monthNames[report.Month] : report.Month.ToString();
+        var s          = GetAggregatedStrings(language, "monthly");
+        var subject    = $"{s.Title} — {installationName} ({monthName} {report.Year})";
+        var html       = BuildAggregatedHtmlEmail(report.PeriodStart, report.PeriodEnd, installationName,
+            report.TotalPvProduction, report.TotalConsumption, report.TotalGridImport, report.TotalGridExport,
+            report.TotalBatteryCharged, report.TotalBatteryDischarged, report.TotalEnergySaved, report.TotalSavingsCHF,
+            report.SelfSufficiencyPercent, report.BatteryEfficiencyPercent, report.AiInsight,
+            $"{report.WeekCount} {s.CountLabel}", s);
+
+        await SendHtmlEmailAsync(subject, html, recipientEmail);
+    }
+
+    public static async Task SendYearlyReportEmailAsync(
+        YearlyReportSummary report,
+        string installationName,
+        string recipientEmail,
+        string language = "en")
+    {
+        var s       = GetAggregatedStrings(language, "yearly");
+        var subject = $"{s.Title} — {installationName} ({report.Year})";
+        var html    = BuildAggregatedHtmlEmail(report.PeriodStart, report.PeriodEnd, installationName,
+            report.TotalPvProduction, report.TotalConsumption, report.TotalGridImport, report.TotalGridExport,
+            report.TotalBatteryCharged, report.TotalBatteryDischarged, report.TotalEnergySaved, report.TotalSavingsCHF,
+            report.SelfSufficiencyPercent, report.BatteryEfficiencyPercent, report.AiInsight,
+            $"{report.MonthCount} {s.CountLabel}", s);
+
+        await SendHtmlEmailAsync(subject, html, recipientEmail);
+    }
+
+    private static async Task SendHtmlEmailAsync(string subject, string html, string recipientEmail)
+    {
+        var config = await ReadMailerConfig();
+        var from   = new MailboxAddress(config.SenderName, config.SenderAddress);
+        var to     = new MailboxAddress(recipientEmail, recipientEmail);
+
+        var msg = new MimeMessage
+        {
+            From    = { from },
+            To      = { to },
+            Subject = subject,
+            Body    = new TextPart("html") { Text = html }
+        };
+
+        using var smtp = new SmtpClient();
+        await smtp.ConnectAsync(config.SmtpServerUrl, config.SmtpPort, SecureSocketOptions.StartTls);
+        await smtp.AuthenticateAsync(config.SmtpUsername, config.SmtpPassword);
+        await smtp.SendAsync(msg);
+        await smtp.DisconnectAsync(true);
+
+        Console.WriteLine($"[ReportEmailService] Report sent to {recipientEmail}");
+    }
+
+    // ── Aggregated report translation strings ─────────────────────────────
+
+    private record AggregatedEmailStrings(
+        string Title, string Insights, string Summary, string SavingsHeader,
+        string Metric, string Total, string PvProduction, string Consumption,
+        string GridImport, string GridExport, string BatteryInOut,
+        string SolarEnergyUsed, string StayedAtHome, string EstMoneySaved,
+        string AtRate, string SolarCoverage, string FromSolar,
+        string BatteryEff, string OutVsIn, string CountLabel, string Footer
+    );
+
+    private static AggregatedEmailStrings GetAggregatedStrings(string language, string type) => (language, type) switch
+    {
+        ("de", "monthly") => new AggregatedEmailStrings(
+            "Monatlicher Leistungsbericht", "Monatliche Erkenntnisse", "Monatliche Zusammenfassung", "Ihre Ersparnisse diesen Monat",
+            "Kennzahl", "Gesamt", "PV-Produktion", "Verbrauch", "Netzbezug", "Netzeinspeisung", "Batterie Laden / Entladen",
+            "Energie gespart", "Solar + Batterie, nicht vom Netz", "Geschätzte Ersparnis", "bei 0.39 CHF/kWh",
+            "Eigenversorgung", "aus Solar + Batterie", "Batterie-Eff.", "Entladung vs. Ladung",
+            "Wochen aggregiert", "Erstellt von <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        ("de", "yearly") => new AggregatedEmailStrings(
+            "Jährlicher Leistungsbericht", "Jährliche Erkenntnisse", "Jährliche Zusammenfassung", "Ihre Ersparnisse dieses Jahr",
+            "Kennzahl", "Gesamt", "PV-Produktion", "Verbrauch", "Netzbezug", "Netzeinspeisung", "Batterie Laden / Entladen",
+            "Energie gespart", "Solar + Batterie, nicht vom Netz", "Geschätzte Ersparnis", "bei 0.39 CHF/kWh",
+            "Eigenversorgung", "aus Solar + Batterie", "Batterie-Eff.", "Entladung vs. Ladung",
+            "Monate aggregiert", "Erstellt von <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        ("fr", "monthly") => new AggregatedEmailStrings(
+            "Rapport de performance mensuel", "Aperçus du mois", "Résumé du mois", "Vos économies ce mois",
+            "Indicateur", "Total", "Production PV", "Consommation", "Import réseau", "Export réseau", "Batterie Charge / Décharge",
+            "Énergie économisée", "solaire + batterie, non achetée au réseau", "Économies estimées", "à 0.39 CHF/kWh",
+            "Autosuffisance", "du solaire + batterie", "Eff. batterie", "décharge vs charge",
+            "semaines agrégées", "Généré par <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        ("fr", "yearly") => new AggregatedEmailStrings(
+            "Rapport de performance annuel", "Aperçus de l'année", "Résumé de l'année", "Vos économies cette année",
+            "Indicateur", "Total", "Production PV", "Consommation", "Import réseau", "Export réseau", "Batterie Charge / Décharge",
+            "Énergie économisée", "solaire + batterie, non achetée au réseau", "Économies estimées", "à 0.39 CHF/kWh",
+            "Autosuffisance", "du solaire + batterie", "Eff. batterie", "décharge vs charge",
+            "mois agrégés", "Généré par <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        ("it", "monthly") => new AggregatedEmailStrings(
+            "Rapporto mensile delle prestazioni", "Approfondimenti mensili", "Riepilogo mensile", "I tuoi risparmi questo mese",
+            "Metrica", "Totale", "Produzione PV", "Consumo", "Import dalla rete", "Export nella rete", "Batteria Carica / Scarica",
+            "Energia risparmiata", "solare + batteria, non acquistata dalla rete", "Risparmio stimato", "a 0.39 CHF/kWh",
+            "Autosufficienza", "da solare + batteria", "Eff. batteria", "scarica vs carica",
+            "settimane aggregate", "Generato da <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        ("it", "yearly") => new AggregatedEmailStrings(
+            "Rapporto annuale delle prestazioni", "Approfondimenti annuali", "Riepilogo annuale", "I tuoi risparmi quest'anno",
+            "Metrica", "Totale", "Produzione PV", "Consumo", "Import dalla rete", "Export nella rete", "Batteria Carica / Scarica",
+            "Energia risparmiata", "solare + batteria, non acquistata dalla rete", "Risparmio stimato", "a 0.39 CHF/kWh",
+            "Autosufficienza", "da solare + batteria", "Eff. batteria", "scarica vs carica",
+            "mesi aggregati", "Generato da <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        (_, "monthly") => new AggregatedEmailStrings(
+            "Monthly Performance Report", "Monthly Insights", "Monthly Summary", "Your Savings This Month",
+            "Metric", "Total", "PV Production", "Consumption", "Grid Import", "Grid Export", "Battery Charge / Discharge",
+            "Energy Saved", "solar + battery, not bought from grid", "Est. Money Saved", "at 0.39 CHF/kWh",
+            "Self-Sufficiency", "from solar + battery", "Battery Eff.", "discharge vs charge",
+            "weeks aggregated", "Generated by <strong style=\"color:#666\">inesco Energy Monitor</strong>"),
+        _ => new AggregatedEmailStrings(
+            "Annual Performance Report", "Annual Insights", "Annual Summary", "Your Savings This Year",
+            "Metric", "Total", "PV Production", "Consumption", "Grid Import", "Grid Export", "Battery Charge / Discharge",
+            "Energy Saved", "solar + battery, not bought from grid", "Est. Money Saved", "at 0.39 CHF/kWh",
+            "Self-Sufficiency", "from solar + battery", "Battery Eff.", "discharge vs charge",
+            "months aggregated", "Generated by <strong style=\"color:#666\">inesco Energy Monitor</strong>")
+    };
+
+    // ── Aggregated HTML email template ────────────────────────────────────
+
+    private static string BuildAggregatedHtmlEmail(
+        string periodStart, string periodEnd, string installationName,
+        double pvProduction, double consumption, double gridImport, double gridExport,
+        double batteryCharged, double batteryDischarged, double energySaved, double savingsCHF,
+        double selfSufficiency, double batteryEfficiency, string aiInsight,
+        string countLabel, AggregatedEmailStrings s)
+    {
+        var insightLines = aiInsight
+            .Split('\n', StringSplitOptions.RemoveEmptyEntries)
+            .Select(l => System.Text.RegularExpressions.Regex.Replace(l.Trim(), @"^[\d]+[.)]\s*|^[-*]\s*", "").Replace("**", ""))
+            .Where(l => l.Length > 0)
+            .ToList();
+
+        var insightHtml = insightLines.Count > 1
+            ? "<ul style=\"margin:0;padding-left:20px\">" +
+              string.Join("", insightLines.Select(l => $"<li style=\"margin-bottom:8px;line-height:1.6\">{FormatInsightLine(l)}</li>")) +
+              "</ul>"
+            : $"<p style=\"margin:0;line-height:1.6\">{FormatInsightLine(aiInsight)}</p>";
+
+        return $@"
+<!DOCTYPE html>
+<html>
+<head><meta charset=""utf-8""></head>
+<body style=""margin:0;padding:0;background:#f4f4f4;font-family:Arial,Helvetica,sans-serif;font-size:14px;color:#333"">
+<table width=""100%"" cellpadding=""0"" cellspacing=""0"" style=""background:#f4f4f4;padding:20px 0"">
+<tr><td align=""center"">
+<table width=""600"" cellpadding=""0"" cellspacing=""0"" style=""background:#ffffff;border-radius:8px;overflow:hidden;box-shadow:0 2px 8px rgba(0,0,0,0.08)"">
+
+    <!-- Header -->
+    <tr>
+        <td style=""background:#2c3e50;padding:24px 30px;color:#ffffff"">
+            <div style=""font-size:20px;font-weight:bold"">{s.Title}</div>
+            <div style=""font-size:14px;margin-top:6px;opacity:0.9"">{installationName}</div>
+            <div style=""font-size:13px;margin-top:2px;opacity:0.7"">{periodStart} — {periodEnd}</div>
+            <div style=""font-size:12px;margin-top:2px;opacity:0.5"">{countLabel}</div>
+        </td>
+    </tr>
+
+    <!-- Insights -->
+    <tr>
+        <td style=""padding:24px 30px 0"">
+            <div style=""font-size:16px;font-weight:bold;margin-bottom:12px;color:#2c3e50"">{s.Insights}</div>
+            <div style=""background:#fef9e7;border-left:4px solid #f39c12;padding:14px 18px;border-radius:0 6px 6px 0;font-size:14px;color:#333"">
+                {insightHtml}
+            </div>
+        </td>
+    </tr>
+
+    <!-- Summary Table -->
+    <tr>
+        <td style=""padding:24px 30px"">
+            <div style=""font-size:16px;font-weight:bold;margin-bottom:12px;color:#2c3e50"">{s.Summary}</div>
+            <table width=""100%"" cellpadding=""0"" cellspacing=""0"" style=""border:1px solid #eee;border-radius:4px"">
+                <tr style=""background:#f8f9fa"">
+                    <th style=""padding:8px 12px;text-align:left"">{s.Metric}</th>
+                    <th style=""padding:8px 12px;text-align:right"">{s.Total}</th>
+                </tr>
+                <tr><td style=""padding:8px 12px;border-bottom:1px solid #eee"">{s.PvProduction}</td><td style=""padding:8px 12px;border-bottom:1px solid #eee;text-align:right;font-weight:bold"">{pvProduction:F1} kWh</td></tr>
+                <tr><td style=""padding:8px 12px;border-bottom:1px solid #eee"">{s.Consumption}</td><td style=""padding:8px 12px;border-bottom:1px solid #eee;text-align:right;font-weight:bold"">{consumption:F1} kWh</td></tr>
+                <tr><td style=""padding:8px 12px;border-bottom:1px solid #eee"">{s.GridImport}</td><td style=""padding:8px 12px;border-bottom:1px solid #eee;text-align:right;font-weight:bold"">{gridImport:F1} kWh</td></tr>
+                <tr><td style=""padding:8px 12px;border-bottom:1px solid #eee"">{s.GridExport}</td><td style=""padding:8px 12px;border-bottom:1px solid #eee;text-align:right;font-weight:bold"">{gridExport:F1} kWh</td></tr>
+                <tr><td style=""padding:8px 12px"">{s.BatteryInOut}</td><td style=""padding:8px 12px;text-align:right;font-weight:bold"">{batteryCharged:F1} / {batteryDischarged:F1} kWh</td></tr>
+            </table>
+        </td>
+    </tr>
+
+    <!-- Key Ratios -->
+    <tr>
+        <td style=""padding:0 30px 24px"">
+            <div style=""font-size:16px;font-weight:bold;margin-bottom:12px;color:#2c3e50"">{s.SavingsHeader}</div>
+            <table width=""100%"" cellpadding=""0"" cellspacing=""8"">
+                <tr>
+                    {SavingsBox(s.SolarEnergyUsed, $"{energySaved:F1} kWh", s.StayedAtHome, "#27ae60")}
+                    {SavingsBox(s.EstMoneySaved, $"~{savingsCHF:F0} CHF", s.AtRate, "#2980b9")}
+                    {SavingsBox(s.SolarCoverage, $"{selfSufficiency:F0}%", s.FromSolar, "#8e44ad")}
+                    {SavingsBox(s.BatteryEff, $"{batteryEfficiency:F0}%", s.OutVsIn, "#e67e22")}
+                </tr>
+            </table>
+        </td>
+    </tr>
+
+    <!-- Footer -->
+    <tr>
+        <td style=""background:#f8f9fa;padding:16px 30px;text-align:center;font-size:12px;color:#999;border-top:1px solid #eee"">
+            {s.Footer}
+        </td>
+    </tr>
+
+</table>
+</td></tr>
+</table>
+</body>
+</html>";
+    }
 }

csharp/App/Backend/Services/WeeklyReportService.cs

@@ -1,4 +1,5 @@
 using Flurl.Http;
+using InnovEnergy.App.Backend.Database;
 using InnovEnergy.App.Backend.DataTypes;
 using Newtonsoft.Json;
 
@@ -8,88 +9,145 @@ public static class WeeklyReportService
 {
     private static readonly string TmpReportDir = Environment.CurrentDirectory + "/tmp_report/";
 
+    // ── Calendar Week Helpers ──────────────────────────────────────────
+
+    /// <summary>
+    /// Returns the last completed calendar week (Mon–Sun).
+    /// Example: called on Wednesday 2026-03-11 → returns (2026-03-02, 2026-03-08).
+    /// </summary>
+    public static (DateOnly Monday, DateOnly Sunday) LastCalendarWeek()
+    {
+        var today           = DateOnly.FromDateTime(DateTime.UtcNow);
+        // DayOfWeek: Sun=0, Mon=1, ..., Sat=6
+        // daysSinceMonday: Mon=0, Tue=1, ..., Sun=6
+        var daysSinceMonday = ((Int32)today.DayOfWeek + 6) % 7;
+        var thisMonday      = today.AddDays(-daysSinceMonday);
+        var lastMonday      = thisMonday.AddDays(-7);
+        var lastSunday      = thisMonday.AddDays(-1);
+        return (lastMonday, lastSunday);
+    }
+
+    /// <summary>
+    /// Returns the calendar week before last (for comparison).
+    /// </summary>
+    private static (DateOnly Monday, DateOnly Sunday) PreviousCalendarWeek()
+    {
+        var (lastMon, _) = LastCalendarWeek();
+        return (lastMon.AddDays(-7), lastMon.AddDays(-1));
+    }
+
+    // ── Report Generation ──────────────────────────────────────────────
+
     /// <summary>
     /// Generates a full weekly report for the given installation.
-    /// Cache is invalidated automatically when the xlsx file is newer than the cache.
+    /// Data source priority:
-    /// To force regeneration (e.g. after a prompt change), simply delete the cache files.
+    ///   1. DailyEnergyRecord rows in SQLite (populated by DailyIngestionService)
+    ///   2. xlsx file fallback (if DB not yet populated for the target week)
+    /// Cache is keyed to the calendar week — invalidated when the week changes.
+    /// Pass weekStartOverride to generate a report for a specific historical week (disables cache).
     /// </summary>
-    public static async Task<WeeklyReportResponse> GenerateReportAsync(long installationId, string installationName, string language = "en")
+    public static async Task<WeeklyReportResponse> GenerateReportAsync(
+        long installationId, string installationName, string language = "en",
+        DateOnly? weekStartOverride = null)
     {
-        var xlsxPath  = TmpReportDir + installationId + ".xlsx";
+        DateOnly curMon, curSun, prevMon, prevSun;
-        var cachePath = TmpReportDir + $"{installationId}_{language}.cache.json";
 
-        // Use cached report if xlsx hasn't changed since cache was written
+        if (weekStartOverride.HasValue)
-        if (File.Exists(cachePath) && File.Exists(xlsxPath))
         {
-            var xlsxModified  = File.GetLastWriteTimeUtc(xlsxPath);
+            // Debug/backfill mode: use the provided Monday as the week start
-            var cacheModified = File.GetLastWriteTimeUtc(cachePath);
+            curMon  = weekStartOverride.Value;
-            if (cacheModified > xlsxModified)
+            curSun  = curMon.AddDays(6);
-            {
+            prevMon = curMon.AddDays(-7);
-                try
+            prevSun = curMon.AddDays(-1);
-                {
-                    var cached = JsonConvert.DeserializeObject<WeeklyReportResponse>(
-                        await File.ReadAllTextAsync(cachePath));
-                    if (cached != null)
-                    {
-                        Console.WriteLine($"[WeeklyReportService] Returning cached report for installation {installationId} ({language}).");
-                        return cached;
-                    }
-                }
-                catch
-                {
-                    // Cache corrupt — regenerate
-                }
-            }
-        }
-
-        // Parse both daily summaries and hourly intervals from the same xlsx
-        var allDays   = ExcelDataParser.Parse(xlsxPath);
-        var allHourly = ExcelDataParser.ParseHourly(xlsxPath);
-        var report    = await GenerateReportFromDataAsync(allDays, allHourly, installationName, language);
-
-        // Write cache
-        try
-        {
-            await File.WriteAllTextAsync(cachePath, JsonConvert.SerializeObject(report));
-        }
-        catch (Exception ex)
-        {
-            Console.Error.WriteLine($"[WeeklyReportService] Could not write cache: {ex.Message}");
-        }
-
-        return report;
-    }
-
-    /// <summary>
-    /// Core report generation. Accepts both daily summaries and hourly intervals.
-    /// </summary>
-    public static async Task<WeeklyReportResponse> GenerateReportFromDataAsync(
-        List<DailyEnergyData> allDays,
-        List<HourlyEnergyData> allHourly,
-        string installationName,
-        string language = "en")
-    {
-        // Sort by date
-        allDays = allDays.OrderBy(d => d.Date).ToList();
-
-        // Split into previous week and current week (daily)
-        List<DailyEnergyData> previousWeekDays;
-        List<DailyEnergyData> currentWeekDays;
-
-        if (allDays.Count > 7)
-        {
-            previousWeekDays = allDays.Take(allDays.Count - 7).ToList();
-            currentWeekDays  = allDays.Skip(allDays.Count - 7).ToList();
         }
         else
         {
-            previousWeekDays = new List<DailyEnergyData>();
+            (curMon, curSun)   = LastCalendarWeek();
-            currentWeekDays  = allDays;
+            (prevMon, prevSun) = PreviousCalendarWeek();
         }
 
-        // Restrict hourly data to current week only for behavioral analysis
+        // 1. Load daily records from SQLite
-        var currentWeekStart  = DateTime.Parse(currentWeekDays.First().Date);
+        var currentWeekDays  = Db.GetDailyRecords(installationId, curMon, curSun)
-        var currentHourlyData = allHourly.Where(h => h.DateTime.Date >= currentWeekStart.Date).ToList();
+            .Select(ToDailyEnergyData).ToList();
+        var previousWeekDays = Db.GetDailyRecords(installationId, prevMon, prevSun)
+            .Select(ToDailyEnergyData).ToList();
+
+        // 2. Fallback: if DB empty, parse xlsx on the fly (pre-ingestion scenario)
+        if (currentWeekDays.Count == 0)
+        {
+            var xlsxFiles = Directory.Exists(TmpReportDir)
+                ? Directory.GetFiles(TmpReportDir, $"{installationId}*.xlsx").OrderBy(f => f).ToList()
+                : new List<String>();
+
+            if (xlsxFiles.Count > 0)
+            {
+                Console.WriteLine($"[WeeklyReportService] DB empty for week {curMon:yyyy-MM-dd}, falling back to xlsx.");
+                var allDaysParsed = xlsxFiles.SelectMany(p => ExcelDataParser.Parse(p)).ToList();
+                currentWeekDays  = allDaysParsed
+                    .Where(d => { var date = DateOnly.Parse(d.Date); return date >= curMon && date <= curSun; })
+                    .ToList();
+                previousWeekDays = allDaysParsed
+                    .Where(d => { var date = DateOnly.Parse(d.Date); return date >= prevMon && date <= prevSun; })
+                    .ToList();
+            }
+        }
+
+        if (currentWeekDays.Count == 0)
+            throw new InvalidOperationException(
+                $"No energy data available for week {curMon:yyyy-MM-dd}–{curSun:yyyy-MM-dd}. " +
+                "Upload an xlsx file or wait for daily ingestion.");
+
+        // 3. Load hourly records from SQLite for behavioral analysis
+        var currentHourlyData = Db.GetHourlyRecords(installationId, curMon, curSun)
+            .Select(ToHourlyEnergyData).ToList();
+
+        return await GenerateReportFromDataAsync(
+            currentWeekDays, previousWeekDays, currentHourlyData, installationName, language,
+            curMon, curSun);
+    }
+
+    // ── Conversion helpers ─────────────────────────────────────────────
+
+    private static DailyEnergyData ToDailyEnergyData(DailyEnergyRecord r) => new()
+    {
+        Date              = r.Date,
+        PvProduction      = r.PvProduction,
+        LoadConsumption   = r.LoadConsumption,
+        GridImport        = r.GridImport,
+        GridExport        = r.GridExport,
+        BatteryCharged    = r.BatteryCharged,
+        BatteryDischarged = r.BatteryDischarged,
+    };
+
+    private static HourlyEnergyData ToHourlyEnergyData(HourlyEnergyRecord r) => new()
+    {
+        DateTime             = DateTime.ParseExact(r.DateHour, "yyyy-MM-dd HH", null),
+        Hour                 = r.Hour,
+        DayOfWeek            = r.DayOfWeek,
+        IsWeekend            = r.IsWeekend,
+        PvKwh                = r.PvKwh,
+        LoadKwh              = r.LoadKwh,
+        GridImportKwh        = r.GridImportKwh,
+        BatteryChargedKwh    = r.BatteryChargedKwh,
+        BatteryDischargedKwh = r.BatteryDischargedKwh,
+        BattSoC              = r.BattSoC,
+    };
+
+    /// <summary>
+    /// Core report generation. Accepts pre-split current/previous week data and hourly intervals.
+    /// weekStart/weekEnd are used to set PeriodStart/PeriodEnd on the response.
+    /// </summary>
+    public static async Task<WeeklyReportResponse> GenerateReportFromDataAsync(
+        List<DailyEnergyData> currentWeekDays,
+        List<DailyEnergyData> previousWeekDays,
+        List<HourlyEnergyData> currentHourlyData,
+        string installationName,
+        string language = "en",
+        DateOnly? weekStart = null,
+        DateOnly? weekEnd   = null)
+    {
+        currentWeekDays  = currentWeekDays.OrderBy(d => d.Date).ToList();
+        previousWeekDays = previousWeekDays.OrderBy(d => d.Date).ToList();
 
         var currentSummary  = Summarize(currentWeekDays);
         var previousSummary = previousWeekDays.Count > 0 ? Summarize(previousWeekDays) : null;
@@ -149,7 +207,7 @@ public static class WeeklyReportService
             PvChangePercent          = pvChange,
             ConsumptionChangePercent = consumptionChange,
             GridImportChangePercent  = gridImportChange,
-            DailyData                = allDays,
+            DailyData                = currentWeekDays,
             Behavior                 = behavior,
             AiInsight                = aiInsight,
         };

typescript/frontend-marios2/src/lang/de.json

@@ -133,6 +133,28 @@
   "confirmBatteryLogDownload": "Möchten Sie das Batterieprotokoll wirklich herunterladen?",
   "downloadBatteryLogFailed": "Herunterladen des Batterieprotokolls fehlgeschlagen, bitte versuchen Sie es erneut.",
   "noReportData": "Keine Berichtsdaten gefunden.",
+  "weeklyTab": "Wöchentlich",
+  "monthlyTab": "Monatlich",
+  "yearlyTab": "Jährlich",
+  "monthlyReportTitle": "Monatlicher Leistungsbericht",
+  "yearlyReportTitle": "Jährlicher Leistungsbericht",
+  "monthlyInsights": "Monatliche Einblicke",
+  "yearlyInsights": "Jährliche Einblicke",
+  "monthlySavings": "Ihre Einsparungen diesen Monat",
+  "yearlySavings": "Ihre Einsparungen dieses Jahr",
+  "monthlySummary": "Monatliche Zusammenfassung",
+  "yearlySummary": "Jährliche Zusammenfassung",
+  "total": "Gesamt",
+  "weeksAggregated": "{count} Wochen aggregiert",
+  "monthsAggregated": "{count} Monate aggregiert",
+  "noMonthlyData": "Noch keine monatlichen Berichte verfügbar. Wöchentliche Berichte erscheinen hier zur Aggregation.",
+  "noYearlyData": "Noch keine jährlichen Berichte verfügbar. Monatliche Berichte erscheinen hier zur Aggregation.",
+  "availableForGeneration": "Zur Generierung verfügbar",
+  "generateMonth": "{month} {year} generieren ({count} Wochen)",
+  "generateYear": "{year} generieren ({count} Monate)",
+  "generatingMonthly": "Wird generiert...",
+  "generatingYearly": "Wird generiert...",
+  "thisMonthWeeklyReports": "Wöchentliche Berichte dieses Monats",
   "ai_analyzing": "KI analysiert...",
   "ai_show_details": "Details anzeigen",
   "ai_show_less": "Weniger anzeigen",

typescript/frontend-marios2/src/lang/en.json

@@ -115,6 +115,28 @@
   "confirmBatteryLogDownload": "Do you really want to download battery log?",
   "downloadBatteryLogFailed": "Download battery log failed, please try again.",
   "noReportData": "No report data found.",
+  "weeklyTab": "Weekly",
+  "monthlyTab": "Monthly",
+  "yearlyTab": "Yearly",
+  "monthlyReportTitle": "Monthly Performance Report",
+  "yearlyReportTitle": "Annual Performance Report",
+  "monthlyInsights": "Monthly Insights",
+  "yearlyInsights": "Annual Insights",
+  "monthlySavings": "Your Savings This Month",
+  "yearlySavings": "Your Savings This Year",
+  "monthlySummary": "Monthly Summary",
+  "yearlySummary": "Annual Summary",
+  "total": "Total",
+  "weeksAggregated": "{count} weeks aggregated",
+  "monthsAggregated": "{count} months aggregated",
+  "noMonthlyData": "No monthly reports available yet. Weekly reports will appear here for aggregation once generated.",
+  "noYearlyData": "No yearly reports available yet. Monthly reports will appear here for aggregation once generated.",
+  "availableForGeneration": "Available for Generation",
+  "generateMonth": "Generate {month} {year} ({count} weeks)",
+  "generateYear": "Generate {year} ({count} months)",
+  "generatingMonthly": "Generating...",
+  "generatingYearly": "Generating...",
+  "thisMonthWeeklyReports": "This Month's Weekly Reports",
   "ai_analyzing": "AI is analyzing...",
   "ai_show_details": "Show details",
   "ai_show_less": "Show less",

typescript/frontend-marios2/src/lang/fr.json

@@ -127,6 +127,28 @@
   "confirmBatteryLogDownload": "Voulez-vous vraiment télécharger le journal de la batterie?",
   "downloadBatteryLogFailed": "Échec du téléchargement du journal de la batterie, veuillez réessayer.",
   "noReportData": "Aucune donnée de rapport trouvée.",
+  "weeklyTab": "Hebdomadaire",
+  "monthlyTab": "Mensuel",
+  "yearlyTab": "Annuel",
+  "monthlyReportTitle": "Rapport de performance mensuel",
+  "yearlyReportTitle": "Rapport de performance annuel",
+  "monthlyInsights": "Aperçus mensuels",
+  "yearlyInsights": "Aperçus annuels",
+  "monthlySavings": "Vos économies ce mois",
+  "yearlySavings": "Vos économies cette année",
+  "monthlySummary": "Résumé mensuel",
+  "yearlySummary": "Résumé annuel",
+  "total": "Total",
+  "weeksAggregated": "{count} semaines agrégées",
+  "monthsAggregated": "{count} mois agrégés",
+  "noMonthlyData": "Aucun rapport mensuel disponible. Les rapports hebdomadaires apparaîtront ici pour l'agrégation.",
+  "noYearlyData": "Aucun rapport annuel disponible. Les rapports mensuels apparaîtront ici pour l'agrégation.",
+  "availableForGeneration": "Disponible pour génération",
+  "generateMonth": "Générer {month} {year} ({count} semaines)",
+  "generateYear": "Générer {year} ({count} mois)",
+  "generatingMonthly": "Génération en cours...",
+  "generatingYearly": "Génération en cours...",
+  "thisMonthWeeklyReports": "Rapports hebdomadaires de ce mois",
   "ai_analyzing": "L'IA analyse...",
   "ai_show_details": "Afficher les détails",
   "ai_show_less": "Afficher moins",

typescript/frontend-marios2/src/lang/it.json

@@ -138,6 +138,28 @@
   "confirmBatteryLogDownload": "Vuoi davvero scaricare il registro della batteria?",
   "downloadBatteryLogFailed": "Download del registro della batteria fallito, riprovare.",
   "noReportData": "Nessun dato del rapporto trovato.",
+  "weeklyTab": "Settimanale",
+  "monthlyTab": "Mensile",
+  "yearlyTab": "Annuale",
+  "monthlyReportTitle": "Rapporto mensile sulle prestazioni",
+  "yearlyReportTitle": "Rapporto annuale sulle prestazioni",
+  "monthlyInsights": "Approfondimenti mensili",
+  "yearlyInsights": "Approfondimenti annuali",
+  "monthlySavings": "I tuoi risparmi questo mese",
+  "yearlySavings": "I tuoi risparmi quest'anno",
+  "monthlySummary": "Riepilogo mensile",
+  "yearlySummary": "Riepilogo annuale",
+  "total": "Totale",
+  "weeksAggregated": "{count} settimane aggregate",
+  "monthsAggregated": "{count} mesi aggregati",
+  "noMonthlyData": "Nessun rapporto mensile ancora disponibile. I rapporti settimanali appariranno qui per l'aggregazione.",
+  "noYearlyData": "Nessun rapporto annuale ancora disponibile. I rapporti mensili appariranno qui per l'aggregazione.",
+  "availableForGeneration": "Disponibile per la generazione",
+  "generateMonth": "Genera {month} {year} ({count} settimane)",
+  "generateYear": "Genera {year} ({count} mesi)",
+  "generatingMonthly": "Generazione in corso...",
+  "generatingYearly": "Generazione in corso...",
+  "thisMonthWeeklyReports": "Rapporti settimanali di questo mese",
   "ai_analyzing": "L'IA sta analizzando...",
   "ai_show_details": "Mostra dettagli",
   "ai_show_less": "Mostra meno",