using InnovEnergy.App.Backend.Database;
using InnovEnergy.App.Backend.DataTypes;

namespace InnovEnergy.App.Backend.Services;

/// <summary>
/// Ingests daily energy totals into the DailyEnergyRecord SQLite table.
/// Data source priority: JSON (local) → JSON (S3) → xlsx fallback.
/// 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 readonly String JsonAggregatedDir =
        Environment.CurrentDirectory + "/tmp_report/aggregated/";

    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>
    /// Ingests data for one installation. Tries JSON (local + S3) and xlsx.
    /// Both sources are tried — idempotency checks prevent duplicates.
    /// JSON provides recent data; xlsx provides historical data.
    /// </summary>
    public static async Task IngestInstallationAsync(Int64 installationId)
    {
        await TryIngestFromJson(installationId);
        IngestFromXlsx(installationId);
    }

    private static async Task<Boolean> TryIngestFromJson(Int64 installationId)
    {
        var newDaily  = 0;
        var newHourly = 0;
        var jsonDir   = Path.Combine(JsonAggregatedDir, installationId.ToString());

        // Collect JSON content from local files
        var jsonFiles = Directory.Exists(jsonDir)
            ? Directory.GetFiles(jsonDir, "*.json")
            : Array.Empty<String>();

        foreach (var jsonPath in jsonFiles.OrderBy(f => f))
        {
            var content = File.ReadAllText(jsonPath);
            var (d, h) = IngestJsonContent(installationId, content);
            newDaily  += d;
            newHourly += h;
        }

        // Also try S3 for recent days (yesterday + today) if no local files found
        if (jsonFiles.Length == 0)
        {
            var installation = Db.GetInstallationById(installationId);
            if (installation is not null)
            {
                for (var daysBack = 0; daysBack <= 1; daysBack++)
                {
                    var date    = DateOnly.FromDateTime(DateTime.UtcNow.AddDays(-daysBack));
                    var isoDate = date.ToString("yyyy-MM-dd");

                    if (Db.DailyRecordExists(installationId, isoDate))
                        continue;

                    var content = await AggregatedJsonParser.TryReadFromS3(installation, isoDate);
                    if (content is null) continue;

                    var (d, h) = IngestJsonContent(installationId, content);
                    newDaily  += d;
                    newHourly += h;
                }
            }
        }

        if (newDaily > 0 || newHourly > 0)
            Console.WriteLine($"[DailyIngestion] Installation {installationId} (JSON): {newDaily} day(s), {newHourly} hour(s) ingested.");

        return newDaily > 0 || newHourly > 0;
    }

    public static (Int32 daily, Int32 hourly) IngestJsonContent(Int64 installationId, String content)
    {
        var newDaily  = 0;
        var newHourly = 0;

        foreach (var day in AggregatedJsonParser.ParseDaily(content))
        {
            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"),
            });
            newDaily++;
        }

        foreach (var hour in AggregatedJsonParser.ParseHourly(content))
        {
            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              = 0,
                CreatedAt            = DateTime.UtcNow.ToString("o"),
            });
            newHourly++;
        }

        return (newDaily, newHourly);
    }

    private static void IngestFromXlsx(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))
        {
            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++;
            }

            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} (xlsx): {newDailyCount} new day(s), {newHourlyCount} new hour(s) ingested ({totalParsed} days across {xlsxFiles.Length} file(s)).");
    }
}