restructured data pipeline for report system and updated the way to create monthly and yearly report

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)
@@ -911,17 +912,23 @@ public class Controller : ControllerBase
         if (installation is null || !user.HasAccessTo(installation))
             return Unauthorized();
 
-        var filePath = Environment.CurrentDirectory + "/tmp_report/" + installationId + ".xlsx";
-        if (!System.IO.File.Exists(filePath))
-            return NotFound($"No report data file found. Please place the Excel export at: tmp_report/{installationId}.xlsx");
+        // Parse optional weekStart override (must be a Monday; any valid date accepted for flexibility)
+        DateOnly? weekStartDate = null;
+        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 for future monthly aggregation (idempotent)
-            ReportAggregationService.SaveWeeklySummary(installationId, report);
+            // Persist weekly summary and seed AiInsightCache for this language
+            ReportAggregationService.SaveWeeklySummary(installationId, report, lang);
 
             return Ok(report);
         }
@@ -991,7 +998,8 @@ public class Controller : ControllerBase
     }
 
     [HttpGet(nameof(GetMonthlyReports))]
-    public ActionResult<List<MonthlyReportSummary>> GetMonthlyReports(Int64 installationId, Token authToken)
+    public async Task<ActionResult<List<MonthlyReportSummary>>> GetMonthlyReports(
+        Int64 installationId, Token authToken, String? language = null)
     {
         var user = Db.GetSession(authToken)?.User;
         if (user == null)
@@ -1001,11 +1009,16 @@ public class Controller : ControllerBase
         if (installation is null || !user.HasAccessTo(installation))
             return Unauthorized();
 
-        return Ok(Db.GetMonthlyReports(installationId));
+        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 ActionResult<List<YearlyReportSummary>> GetYearlyReports(Int64 installationId, Token authToken)
+    public async Task<ActionResult<List<YearlyReportSummary>>> GetYearlyReports(
+        Int64 installationId, Token authToken, String? language = null)
     {
         var user = Db.GetSession(authToken)?.User;
         if (user == null)
@@ -1015,12 +1028,16 @@ public class Controller : ControllerBase
         if (installation is null || !user.HasAccessTo(installation))
             return Unauthorized();
 
-        return Ok(Db.GetYearlyReports(installationId));
+        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.
-    /// Aggregates weekly reports for the specified year/month into a monthly report.
+    /// 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)
@@ -1039,11 +1056,11 @@ public class Controller : ControllerBase
         try
         {
             var lang      = user.Language ?? "en";
-            var weekCount = await ReportAggregationService.TriggerMonthlyAggregationAsync(installationId, year, month, lang);
-            if (weekCount == 0)
-                return NotFound($"No weekly reports found for {year}-{month:D2}.");
+            var dayCount  = await ReportAggregationService.TriggerMonthlyAggregationAsync(installationId, year, month, lang);
+            if (dayCount == 0)
+                return NotFound($"No daily records found for {year}-{month:D2}.");
 
-            return Ok(new { message = $"Monthly report created from {weekCount} weekly reports for {year}-{month:D2}." });
+            return Ok(new { message = $"Monthly report created from {dayCount} daily records for {year}-{month:D2}." });
         }
         catch (Exception ex)
         {
@@ -1083,6 +1100,119 @@ public class Controller : ControllerBase
         }
     }
 
+    /// <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)
     {
@@ -1101,6 +1231,7 @@ public class Controller : ControllerBase
         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}" });
         }
@@ -1129,6 +1260,7 @@ public class Controller : ControllerBase
         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}" });
         }
@@ -1140,7 +1272,8 @@ public class Controller : ControllerBase
     }
 
     [HttpGet(nameof(GetWeeklyReportSummaries))]
-    public ActionResult<List<WeeklyReportSummary>> GetWeeklyReportSummaries(Int64 installationId, Int32 year, Int32 month, Token authToken)
+    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)
@@ -1150,7 +1283,11 @@ public class Controller : ControllerBase
         if (installation is null || !user.HasAccessTo(installation))
             return Unauthorized();
 
-        return Ok(Db.GetWeeklyReportsForMonth(installationId, year, month));
+        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))]

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/Database/Create.cs

@@ -71,6 +71,8 @@ public static partial class Db
     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(AiInsightCache cache)        => Insert(cache);
     
     public static void HandleAction(UserAction newAction)
     {

csharp/App/Backend/Database/Db.cs

@@ -28,6 +28,8 @@ public static partial class Db
     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<AiInsightCache>       AiInsightCaches   => Connection.Table<AiInsightCache>();
 
 
     public static void Init()
@@ -57,6 +59,8 @@ public static partial class Db
             Connection.CreateTable<WeeklyReportSummary>();
             Connection.CreateTable<MonthlyReportSummary>();
             Connection.CreateTable<YearlyReportSummary>();
+            Connection.CreateTable<DailyEnergyRecord>();
+            Connection.CreateTable<AiInsightCache>();
         });
         
         // One-time migration: normalize legacy long-form language values to ISO codes
@@ -97,6 +101,7 @@ public static partial class Db
         fileConnection.CreateTable<WeeklyReportSummary>();
         fileConnection.CreateTable<MonthlyReportSummary>();
         fileConnection.CreateTable<YearlyReportSummary>();
+        fileConnection.CreateTable<DailyEnergyRecord>();
 
         return fileConnection;
         //return CopyDbToMemory(fileConnection);

csharp/App/Backend/Database/Delete.cs

@@ -180,4 +180,57 @@ public static partial class Db
         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);
+
+        // 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, {oldWeeklyIds.Count} weekly, {oldMonthlyIds.Count} monthly, {oldCacheIds.Count} insight cache records deleted (cutoff {cutoff}).");
+    }
 }

csharp/App/Backend/Database/Read.cs

@@ -94,4 +94,41 @@ public static partial class Db
             .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);
+
+    // ── 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

@@ -28,7 +28,8 @@ public static class Program
         LoadEnvFile();
         DiagnosticService.Initialize();
         AlarmReviewService.StartDailyScheduler();
-        // ReportAggregationService.StartScheduler(); // TODO: uncomment to enable automatic monthly/yearly aggregation
+        // 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 +1,137 @@
+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 newCount    = 0;
+        var totalParsed = 0;
+
+        foreach (var xlsxPath in xlsxFiles.OrderBy(f => f))
+        {
+            List<DailyEnergyData> days;
+            try
+            {
+                days = ExcelDataParser.Parse(xlsxPath);
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[DailyIngestion] Failed to parse {Path.GetFileName(xlsxPath)}: {ex.Message}");
+                continue;
+            }
+
+            totalParsed += days.Count;
+
+            foreach (var day in days)
+            {
+                if (Db.DailyRecordExists(installationId, day.Date))
+                    continue;
+
+                Db.Create(new DailyEnergyRecord
+                {
+                    InstallationId    = installationId,
+                    Date              = day.Date,
+                    PvProduction      = day.PvProduction,
+                    LoadConsumption   = day.LoadConsumption,
+                    GridImport        = day.GridImport,
+                    GridExport        = day.GridExport,
+                    BatteryCharged    = day.BatteryCharged,
+                    BatteryDischarged = day.BatteryDischarged,
+                    CreatedAt         = DateTime.UtcNow.ToString("o"),
+                });
+                newCount++;
+            }
+        }
+
+        Console.WriteLine($"[DailyIngestion] Installation {installationId}: {newCount} new day(s) ingested ({totalParsed} total across {xlsxFiles.Length} file(s)).");
+        await Task.CompletedTask;
+    }
+}

csharp/App/Backend/Services/ReportAggregationService.cs

@@ -167,7 +167,7 @@ public static class ReportAggregationService
 
     // ── Save Weekly Summary ───────────────────────────────────────────
 
-    public static void SaveWeeklySummary(Int64 installationId, WeeklyReportResponse report)
+    public static void SaveWeeklySummary(Int64 installationId, WeeklyReportResponse report, String language = "en")
     {
         try
         {
@@ -211,6 +211,18 @@ public static class ReportAggregationService
             };
 
             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)
@@ -272,12 +284,14 @@ public static class ReportAggregationService
     /// </summary>
     public static async Task<Int32> TriggerMonthlyAggregationAsync(Int64 installationId, Int32 year, Int32 month, String language = "en")
     {
-        var weeklies = Db.GetWeeklyReportsForMonth(installationId, year, month);
-        if (weeklies.Count == 0)
+        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 weeklies.Count;
+        return days.Count;
     }
 
     /// <summary>
@@ -300,10 +314,15 @@ public static class ReportAggregationService
         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}...");
 
-        var installationIds = Db.WeeklyReports
+        // 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()
@@ -314,11 +333,6 @@ public static class ReportAggregationService
             try
             {
                 await AggregateMonthForInstallation(installationId, year, month);
-
-                // Scheduler mode: clean up weekly records after successful aggregation.
-                // The monthly report is now the source of truth for this month.
-                Db.DeleteWeeklyReportsForMonth(installationId, year, month);
-                Console.WriteLine($"[ReportAggregation] Cleaned up weekly records for installation {installationId}, {year}-{month:D2}.");
             }
             catch (Exception ex)
             {
@@ -329,23 +343,25 @@ public static class ReportAggregationService
 
     private static async Task AggregateMonthForInstallation(Int64 installationId, Int32 year, Int32 month, String language = "en")
     {
-        var weeklies = Db.GetWeeklyReportsForMonth(installationId, year, month);
-        if (weeklies.Count == 0)
+        // 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 with latest weekly data.
-        // This supports partial months and re-aggregation when new weekly data arrives.
+        // If monthly report already exists, delete it so we can re-generate
         Db.DeleteMonthlyReport(installationId, year, month);
 
-        // Sum energy totals
-        var totalPv       = Math.Round(weeklies.Sum(w => w.TotalPvProduction), 1);
-        var totalConsump  = Math.Round(weeklies.Sum(w => w.TotalConsumption), 1);
-        var totalGridIn   = Math.Round(weeklies.Sum(w => w.TotalGridImport), 1);
-        var totalGridOut  = Math.Round(weeklies.Sum(w => w.TotalGridExport), 1);
-        var totalBattChg  = Math.Round(weeklies.Sum(w => w.TotalBatteryCharged), 1);
-        var totalBattDis  = Math.Round(weeklies.Sum(w => w.TotalBatteryDischarged), 1);
+        // 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 from aggregated totals
+        // 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;
@@ -353,56 +369,59 @@ public static class ReportAggregationService
         var batteryEff      = totalBattChg > 0 ? Math.Round(totalBattDis / totalBattChg * 100, 1) : 0;
         var gridDependency  = totalConsump > 0 ? Math.Round(totalGridIn / totalConsump * 100, 1) : 0;
 
-        // Average behavioral highlights
-        var avgPeakLoad    = (Int32)Math.Round(weeklies.Average(w => w.PeakLoadHour));
-        var avgPeakSolar   = (Int32)Math.Round(weeklies.Average(w => w.PeakSolarHour));
-        var avgWeekdayLoad = Math.Round(weeklies.Average(w => w.WeekdayAvgDailyLoad), 1);
-        var avgWeekendLoad = Math.Round(weeklies.Average(w => w.WeekendAvgDailyLoad), 1);
-
         // 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, weeklies.Count,
+            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             = weeklies.Min(w => w.PeriodStart),
-            PeriodEnd               = weeklies.Max(w => w.PeriodEnd),
-            TotalPvProduction       = totalPv,
-            TotalConsumption        = totalConsump,
-            TotalGridImport         = totalGridIn,
-            TotalGridExport         = totalGridOut,
-            TotalBatteryCharged     = totalBattChg,
-            TotalBatteryDischarged  = totalBattDis,
-            TotalEnergySaved        = energySaved,
-            TotalSavingsCHF         = savingsCHF,
-            SelfSufficiencyPercent  = selfSufficiency,
-            SelfConsumptionPercent  = selfConsumption,
+            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         = avgPeakLoad,
-            AvgPeakSolarHour        = avgPeakSolar,
-            AvgWeekdayDailyLoad     = avgWeekdayLoad,
-            AvgWeekendDailyLoad     = avgWeekendLoad,
-            WeekCount               = weeklies.Count,
-            AiInsight               = aiInsight,
-            CreatedAt               = DateTime.UtcNow.ToString("o"),
+            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);
-        // Weekly records are kept — allows re-generation if new weekly data arrives.
-        // Cleanup can be done later by the automated scheduler or manually.
 
-        Console.WriteLine($"[ReportAggregation] Monthly report created for installation {installationId}, {year}-{month:D2} ({weeklies.Count} weeks aggregated).");
+        // Seed AiInsightCache so the generating language is pre-cached
+        if (!String.IsNullOrEmpty(monthlySummary.AiInsight))
+            Db.Create(new AiInsightCache
+            {
+                ReportType  = "monthly",
+                ReportId    = monthlySummary.Id,
+                Language    = language,
+                InsightText = monthlySummary.AiInsight,
+                CreatedAt   = monthlySummary.CreatedAt,
+            });
+
+        Console.WriteLine($"[ReportAggregation] Monthly report created for installation {installationId}, {year}-{month:D2} ({days.Count} days, {first}–{last}).");
     }
 
     // ── Year-End Aggregation ──────────────────────────────────────────
@@ -425,17 +444,15 @@ public static class ReportAggregationService
             try
             {
                 await AggregateYearForInstallation(installationId, previousYear);
-
-                // Scheduler mode: clean up monthly records after successful aggregation.
-                // The yearly report is now the source of truth for this year.
-                Db.DeleteMonthlyReportsForYear(installationId, previousYear);
-                Console.WriteLine($"[ReportAggregation] Cleaned up monthly records for installation {installationId}, {previousYear}.");
             }
             catch (Exception ex)
             {
                 Console.Error.WriteLine($"[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")
@@ -505,13 +522,140 @@ public static class ReportAggregationService
         };
 
         Db.Create(yearlySummary);
-        // Monthly records are kept — allows re-generation if new monthly data arrives.
+
+        // 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",
@@ -533,26 +677,28 @@ public static class ReportAggregationService
             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} weeks):
-- Total PV production: {totalPv:F1} kWh
+MONTHLY FACTS for {monthName} ({weekCount} days of data):
+- 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}%
+- Self-sufficiency: {selfSufficiency:F1}% (powered by solar + battery, not 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. Monthly savings summary: total energy saved and money saved this month. Use the exact numbers provided.
-2. Solar & battery performance: comment on PV production and battery utilization.
-3. Grid dependency: note grid import relative to total consumption.
-4. Recommendation for next month: one actionable suggestion.
+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. ""X% of your home ran on solar + battery""). 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. 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.";
+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);
     }

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();
 
@@ -584,7 +584,7 @@ public static class ReportEmailService
     {
         var insightLines = 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();
 

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;
 
@@ -8,22 +9,73 @@ 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.
-    /// To force regeneration (e.g. after a prompt change), simply delete the cache files.
+    /// Data source priority:
+    ///   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";
-        var cachePath = TmpReportDir + $"{installationId}_{language}.cache.json";
+        DateOnly curMon, curSun, prevMon, prevSun;
 
-        // Use cached report if xlsx hasn't changed since cache was written
-        if (File.Exists(cachePath) && File.Exists(xlsxPath))
+        if (weekStartOverride.HasValue)
         {
-            var xlsxModified  = File.GetLastWriteTimeUtc(xlsxPath);
-            var cacheModified = File.GetLastWriteTimeUtc(cachePath);
-            if (cacheModified > xlsxModified)
+            // Debug/backfill mode: use the provided Monday as the week start
+            curMon  = weekStartOverride.Value;
+            curSun  = curMon.AddDays(6);
+            prevMon = curMon.AddDays(-7);
+            prevSun = curMon.AddDays(-1);
+        }
+        else
+        {
+            (curMon, curSun)   = LastCalendarWeek();
+            (prevMon, prevSun) = PreviousCalendarWeek();
+        }
+
+        // Skip file cache when a specific week is requested (avoid stale or wrong-week hits)
+        var cachePath = weekStartOverride.HasValue
+            ? null
+            : TmpReportDir + $"{installationId}_{language}_{curMon:yyyy-MM-dd}.cache.json";
+
+        // Use cache if it exists and is less than 6 hours old (skipped in override mode)
+        if (cachePath != null && File.Exists(cachePath))
+        {
+            var cacheAge = DateTime.UtcNow - File.GetLastWriteTimeUtc(cachePath);
+            if (cacheAge.TotalHours < 6)
             {
                 try
                 {
@@ -31,7 +83,7 @@ public static class WeeklyReportService
                         await File.ReadAllTextAsync(cachePath));
                     if (cached != null)
                     {
-                        Console.WriteLine($"[WeeklyReportService] Returning cached report for installation {installationId} ({language}).");
+                        Console.WriteLine($"[WeeklyReportService] Returning cached report for installation {installationId} ({language}), week {curMon:yyyy-MM-dd}.");
                         return cached;
                     }
                 }
@@ -42,54 +94,94 @@ public static class WeeklyReportService
             }
         }
 
-        // 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);
+        // 1. Try to load daily records from SQLite for the calendar weeks
+        var currentWeekDays  = Db.GetDailyRecords(installationId, curMon, curSun)
+            .Select(r => ToDailyEnergyData(r)).ToList();
+        var previousWeekDays = Db.GetDailyRecords(installationId, prevMon, prevSun)
+            .Select(r => ToDailyEnergyData(r)).ToList();
 
-        // Write cache
-        try
+        // 2. Fallback: if DB empty for current week, parse all xlsx files on the fly
+        var xlsxFiles = Directory.Exists(TmpReportDir)
+            ? Directory.GetFiles(TmpReportDir, $"{installationId}*.xlsx").OrderBy(f => f).ToList()
+            : new List<String>();
+
+        if (currentWeekDays.Count == 0 && xlsxFiles.Count > 0)
         {
-            await File.WriteAllTextAsync(cachePath, JsonConvert.SerializeObject(report));
+            Console.WriteLine($"[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();
         }
-        catch (Exception ex)
+
+        if (currentWeekDays.Count == 0)
+            throw new InvalidOperationException(
+                $"No energy data available for week {curMon:yyyy-MM-dd}–{curSun:yyyy-MM-dd}. " +
+                "Upload an xlsx file or wait for daily ingestion.");
+
+        // 3. Load hourly data from ALL xlsx files for behavioral analysis (current week only).
+        //    Combine all files so any week can find its hourly data regardless of file split.
+        //    Future: replace with S3 hourly fetch.
+        var allHourly = xlsxFiles
+            .SelectMany(p => { try { return ExcelDataParser.ParseHourly(p); } catch { return Enumerable.Empty<HourlyEnergyData>(); } })
+            .ToList();
+        var curMonDt          = curMon.ToDateTime(TimeOnly.MinValue);
+        var curSunDt          = curSun.ToDateTime(TimeOnly.MaxValue);
+        var currentHourlyData = allHourly
+            .Where(h => h.DateTime >= curMonDt && h.DateTime <= curSunDt)
+            .ToList();
+
+        var report = await GenerateReportFromDataAsync(
+            currentWeekDays, previousWeekDays, currentHourlyData, installationName, language,
+            curMon, curSun);
+
+        // Write cache (skipped in override mode)
+        if (cachePath != null)
         {
-            Console.Error.WriteLine($"[WeeklyReportService] Could not write cache: {ex.Message}");
+            try
+            {
+                await File.WriteAllTextAsync(cachePath, JsonConvert.SerializeObject(report));
+            }
+            catch (Exception ex)
+            {
+                Console.Error.WriteLine($"[WeeklyReportService] Could not write cache: {ex.Message}");
+            }
         }
 
         return report;
     }
 
+    // ── 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,
+    };
+
     /// <summary>
-    /// Core report generation. Accepts both daily summaries and hourly intervals.
+    /// 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> allDays,
-        List<HourlyEnergyData> allHourly,
+        List<DailyEnergyData> currentWeekDays,
+        List<DailyEnergyData> previousWeekDays,
+        List<HourlyEnergyData> currentHourlyData,
         string installationName,
-        string language = "en")
+        string language = "en",
+        DateOnly? weekStart = null,
+        DateOnly? weekEnd   = null)
     {
-        // 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>();
-            currentWeekDays  = allDays;
-        }
-
-        // Restrict hourly data to current week only for behavioral analysis
-        var currentWeekStart  = DateTime.Parse(currentWeekDays.First().Date);
-        var currentHourlyData = allHourly.Where(h => h.DateTime.Date >= currentWeekStart.Date).ToList();
+        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 +241,7 @@ public static class WeeklyReportService
             PvChangePercent          = pvChange,
             ConsumptionChangePercent = consumptionChange,
             GridImportChangePercent  = gridImportChange,
-            DailyData                = allDays,
+            DailyData                = currentWeekDays,
             Behavior                 = behavior,
             AiInsight                = aiInsight,
         };

typescript/frontend-marios2/src/content/dashboards/SodiohomeInstallations/WeeklyReport.tsx

@@ -224,10 +224,11 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
   const [generating, setGenerating] = useState<string | null>(null);
 
   const fetchReportData = () => {
-    axiosConfig.get('/GetMonthlyReports', { params: { installationId } })
+    const lang = intl.locale;
+    axiosConfig.get('/GetMonthlyReports', { params: { installationId, language: lang } })
       .then(res => setMonthlyReports(res.data))
       .catch(() => {});
-    axiosConfig.get('/GetYearlyReports', { params: { installationId } })
+    axiosConfig.get('/GetYearlyReports', { params: { installationId, language: lang } })
       .then(res => setYearlyReports(res.data))
       .catch(() => {});
     axiosConfig.get('/GetPendingMonthlyAggregations', { params: { installationId } })
@@ -238,7 +239,7 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
       .catch(() => {});
   };
 
-  useEffect(() => { fetchReportData(); }, [installationId]);
+  useEffect(() => { fetchReportData(); }, [installationId, intl.locale]);
 
   const handleGenerateMonthly = async (year: number, month: number) => {
     setGenerating(`monthly-${year}-${month}`);
@@ -277,7 +278,7 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
   const safeTab = Math.min(activeTab, tabs.length - 1);
 
   return (
-    <Box sx={{ p: 2 }}>
+    <Box sx={{ p: 2, maxWidth: 900, mx: 'auto' }}>
       <Tabs
         value={safeTab}
         onChange={(_, v) => setActiveTab(v)}
@@ -286,10 +287,17 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
         {tabs.map(t => <Tab key={t.key} label={t.label} />)}
       </Tabs>
 
-      {tabs[safeTab]?.key === 'weekly' && (
-        <WeeklySection installationId={installationId} />
-      )}
-      {tabs[safeTab]?.key === 'monthly' && (
+      <Box sx={{ display: tabs[safeTab]?.key === 'weekly' ? 'block' : 'none' }}>
+        <WeeklySection
+          installationId={installationId}
+          latestMonthlyPeriodEnd={
+            monthlyReports.length > 0
+              ? monthlyReports.reduce((a, b) => a.periodEnd > b.periodEnd ? a : b).periodEnd
+              : null
+          }
+        />
+      </Box>
+      <Box sx={{ display: tabs[safeTab]?.key === 'monthly' ? 'block' : 'none' }}>
         <MonthlySection
           installationId={installationId}
           reports={monthlyReports}
@@ -297,8 +305,8 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
           generating={generating}
           onGenerate={handleGenerateMonthly}
         />
-      )}
-      {tabs[safeTab]?.key === 'yearly' && (
+      </Box>
+      <Box sx={{ display: tabs[safeTab]?.key === 'yearly' ? 'block' : 'none' }}>
         <YearlySection
           installationId={installationId}
           reports={yearlyReports}
@@ -306,14 +314,14 @@ function WeeklyReport({ installationId }: WeeklyReportProps) {
           generating={generating}
           onGenerate={handleGenerateYearly}
         />
-      )}
+      </Box>
     </Box>
   );
 }
 
 // ── Weekly Section (existing weekly report content) ────────────
 
-function WeeklySection({ installationId }: { installationId: number }) {
+function WeeklySection({ installationId, latestMonthlyPeriodEnd }: { installationId: number; latestMonthlyPeriodEnd: string | null }) {
   const intl = useIntl();
   const [report, setReport] = useState<WeeklyReportResponse | null>(null);
   const [loading, setLoading] = useState(true);
@@ -391,9 +399,13 @@ function WeeklySection({ installationId }: { installationId: number }) {
     return effective > 0 ? '#27ae60' : effective < 0 ? '#e74c3c' : '#888';
   };
 
+  // Compute change % from two raw values; returns 0 (shown as —) if prev is 0
+  const calcChange = (curVal: number, prevVal: number) =>
+    prevVal === 0 ? 0 : ((curVal - prevVal) / prevVal) * 100;
+
   const insightBullets = report.aiInsight
     .split(/\n+/)
-    .map((line) => line.replace(/^[\d]+[.)]\s*/, '').replace(/^[-*]\s*/, '').trim())
+    .map((line) => line.replace(/\*\*/g, '').replace(/^[\d]+[.)]\s*/, '').replace(/^[-*]\s*/, '').trim())
     .filter((line) => line.length > 0);
 
   const totalEnergySavedKwh = report.totalEnergySaved;
@@ -502,13 +514,13 @@ function WeeklySection({ installationId }: { installationId: number }) {
               <td><FormattedMessage id="gridExport" defaultMessage="Grid Export" /></td>
               <td style={{ textAlign: 'right', fontWeight: 'bold' }}>{cur.totalGridExport.toFixed(1)} kWh</td>
               {prev && <td style={{ textAlign: 'right', color: '#888' }}>{prev.totalGridExport.toFixed(1)} kWh</td>}
-              {prev && <td style={{ textAlign: 'right' }}>—</td>}
+              {prev && <td style={{ textAlign: 'right', color: '#888' }}>{formatChange(calcChange(cur.totalGridExport, prev.totalGridExport))}</td>}
             </tr>
             <tr>
               <td><FormattedMessage id="batteryInOut" defaultMessage="Battery In / Out" /></td>
               <td style={{ textAlign: 'right', fontWeight: 'bold' }}>{cur.totalBatteryCharged.toFixed(1)} / {cur.totalBatteryDischarged.toFixed(1)} kWh</td>
               {prev && <td style={{ textAlign: 'right', color: '#888' }}>{prev.totalBatteryCharged.toFixed(1)} / {prev.totalBatteryDischarged.toFixed(1)} kWh</td>}
-              {prev && <td style={{ textAlign: 'right' }}>—</td>}
+              {prev && <td style={{ textAlign: 'right', color: changeColor(calcChange(cur.totalBatteryCharged, prev.totalBatteryCharged)) }}>{formatChange(calcChange(cur.totalBatteryCharged, prev.totalBatteryCharged))}</td>}
             </tr>
           </tbody>
         </Box>
@@ -557,33 +569,69 @@ function WeeklySection({ installationId }: { installationId: number }) {
         </Paper>
       )}
 
-      {/* Weekly History for current month */}
-      <WeeklyHistory installationId={installationId} />
+      {/* Weekly History — weeks not yet captured in a monthly report, excluding the current week shown above */}
+      <WeeklyHistory
+        installationId={installationId}
+        latestMonthlyPeriodEnd={latestMonthlyPeriodEnd}
+        currentReportPeriodEnd={report?.periodEnd ?? null}
+      />
     </>
   );
 }
 
 // ── Weekly History (saved weekly reports for current month) ─────
 
-function WeeklyHistory({ installationId }: { installationId: number }) {
+function WeeklyHistory({ installationId, latestMonthlyPeriodEnd, currentReportPeriodEnd }: {
+  installationId: number;
+  latestMonthlyPeriodEnd: string | null;
+  currentReportPeriodEnd: string | null;
+}) {
   const intl = useIntl();
   const [records, setRecords] = useState<WeeklyReportSummaryRecord[]>([]);
 
   useEffect(() => {
-    const now = new Date();
-    axiosConfig.get('/GetWeeklyReportSummaries', {
-      params: { installationId, year: now.getFullYear(), month: now.getMonth() + 1 }
-    })
-      .then(res => setRecords(res.data))
-      .catch(() => {});
-  }, [installationId]);
+    const now   = new Date();
+    const year  = now.getFullYear();
+    const month = now.getMonth() + 1;
+    const lang  = intl.locale;
+
+    // Fetch current month and previous month to cover cross-month weeks
+    const prevMonth = month === 1 ? 12 : month - 1;
+    const prevYear  = month === 1 ? year - 1 : year;
+
+    Promise.all([
+      axiosConfig.get('/GetWeeklyReportSummaries', { params: { installationId, year, month, language: lang } })
+        .then(r => r.data as WeeklyReportSummaryRecord[]).catch(() => [] as WeeklyReportSummaryRecord[]),
+      axiosConfig.get('/GetWeeklyReportSummaries', { params: { installationId, year: prevYear, month: prevMonth, language: lang } })
+        .then(r => r.data as WeeklyReportSummaryRecord[]).catch(() => [] as WeeklyReportSummaryRecord[])
+    ]).then(([cur, prev]) => {
+      // Combine, deduplicate by id, sort descending by periodEnd
+      const all    = [...cur, ...prev];
+      const unique = Array.from(new Map(all.map(r => [r.id, r])).values())
+        .sort((a, b) => b.periodEnd.localeCompare(a.periodEnd));
+
+      // Exclude the current week already shown as the main report above
+      const withoutCurrent = currentReportPeriodEnd
+        ? unique.filter(r => r.periodEnd !== currentReportPeriodEnd)
+        : unique;
+
+      // Keep only weeks not yet covered by a monthly report
+      const uncovered = latestMonthlyPeriodEnd
+        ? withoutCurrent.filter(r => r.periodEnd > latestMonthlyPeriodEnd)
+        : withoutCurrent;
+
+      // Always show at least the latest non-current week even if all are covered
+      const toShow = uncovered.length > 0 ? uncovered : withoutCurrent.slice(0, 1);
+      setRecords(toShow);
+    });
+  }, [installationId, latestMonthlyPeriodEnd, currentReportPeriodEnd, intl.locale]);
 
   if (records.length === 0) return null;
 
   return (
     <Paper sx={{ p: 3, mb: 3 }}>
       <Typography variant="h6" fontWeight="bold" sx={{ mb: 2, color: '#2c3e50' }}>
-        <FormattedMessage id="thisMonthWeeklyReports" defaultMessage="This Month's Weekly Reports" />
+        <FormattedMessage id="recentWeeklyReports" defaultMessage="Recent Weekly Reports" />
       </Typography>
       {records.map((rec) => (
         <Accordion key={rec.id} sx={{ mb: 1, '&:before': { display: 'none' } }} disableGutters>
@@ -639,15 +687,6 @@ function WeeklyHistory({ installationId }: { installationId: number }) {
                 </tr>
               </tbody>
             </Box>
-            {rec.aiInsight && rec.aiInsight.length > 10 && (
-              <Box sx={{ mt: 1.5, bgcolor: '#fef9e7', borderLeft: '3px solid #f39c12', p: 1.5, borderRadius: '0 6px 6px 0', fontSize: '12px', color: '#555' }}>
-                {rec.aiInsight.split(/\n+/).filter(l => l.trim()).slice(0, 2).map((line, i) => (
-                  <Typography key={i} variant="caption" display="block" sx={{ lineHeight: 1.5 }}>
-                    {line.replace(/^[-*]\s*/, '').replace(/^[\d]+[.)]\s*/, '')}
-                  </Typography>
-                ))}
-              </Box>
-            )}
           </AccordionDetails>
         </Accordion>
       ))}
@@ -842,7 +881,7 @@ function AggregatedSection<T extends ReportSummary>({
 
   const insightBullets = r.aiInsight
     .split(/\n+/)
-    .map((line) => line.replace(/^[\d]+[.)]\s*/, '').replace(/^[-*]\s*/, '').trim())
+    .map((line) => line.replace(/\*\*/g, '').replace(/^[\d]+[.)]\s*/, '').replace(/^[-*]\s*/, '').trim())
     .filter((line) => line.length > 0);
 
   const handleSendEmail = async (emailAddress: string) => {