using System.Text.Json;
using System.Text.Json.Serialization;
using InnovEnergy.App.Backend.DataTypes;
using InnovEnergy.App.Backend.DataTypes.Methods;
using InnovEnergy.Lib.S3Utils;
using InnovEnergy.Lib.S3Utils.DataTypes;
using S3Region = InnovEnergy.Lib.S3Utils.DataTypes.S3Region;

namespace InnovEnergy.App.Backend.Services;

/// <summary>
/// Parses NDJSON aggregated data files generated by SodistoreHome devices.
/// Each file (DDMMYYYY.json) contains one JSON object per line:
///   - Type "Hourly": per-hour kWh values (already computed, no diffing needed)
///   - Type "Daily": daily totals
/// </summary>
public static class AggregatedJsonParser
{
    private static readonly JsonSerializerOptions JsonOpts = new()
    {
        PropertyNameCaseInsensitive = true,
        NumberHandling = JsonNumberHandling.AllowReadingFromString,
    };

    public static List<DailyEnergyData> ParseDaily(String ndjsonContent)
    {
        var dailyByDate = new SortedDictionary<String, DailyEnergyData>();

        foreach (var line in ndjsonContent.Split('\n', StringSplitOptions.RemoveEmptyEntries))
        {
            if (!line.Contains("\"Type\":\"Daily\""))
                continue;

            try
            {
                var raw = JsonSerializer.Deserialize<DailyJsonDto>(line, JsonOpts);
                if (raw is null) continue;

                var date = raw.Timestamp.ToString("yyyy-MM-dd");

                dailyByDate[date] = new DailyEnergyData
                {
                    Date              = date,
                    PvProduction      = Math.Round(raw.DailySelfGeneratedElectricity, 4),
                    GridImport        = Math.Round(raw.DailyElectricityPurchased, 4),
                    GridExport        = Math.Round(raw.DailyElectricityFed, 4),
                    BatteryCharged    = Math.Round(raw.BatteryDailyChargeEnergy, 4),
                    BatteryDischarged = Math.Round(raw.BatteryDailyDischargeEnergy, 4),
                    LoadConsumption   = Math.Round(raw.DailyLoadPowerConsumption, 4),
                };
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine($"[AggregatedJsonParser] Skipping daily line: {ex.Message}");
            }
        }

        Console.WriteLine($"[AggregatedJsonParser] Parsed {dailyByDate.Count} daily record(s)");
        return dailyByDate.Values.ToList();
    }

    public static List<HourlyEnergyData> ParseHourly(String ndjsonContent)
    {
        var result = new List<HourlyEnergyData>();

        foreach (var line in ndjsonContent.Split('\n', StringSplitOptions.RemoveEmptyEntries))
        {
            if (!line.Contains("\"Type\":\"Hourly\""))
                continue;

            try
            {
                var raw = JsonSerializer.Deserialize<HourlyJsonDto>(line, JsonOpts);
                if (raw is null) continue;

                var dt = new DateTime(
                    raw.Timestamp.Year, raw.Timestamp.Month, raw.Timestamp.Day,
                    raw.Timestamp.Hour, 0, 0);

                result.Add(new HourlyEnergyData
                {
                    DateTime             = dt,
                    Hour                 = dt.Hour,
                    DayOfWeek            = dt.DayOfWeek.ToString(),
                    IsWeekend            = dt.DayOfWeek is System.DayOfWeek.Saturday or System.DayOfWeek.Sunday,
                    PvKwh                = Math.Round(raw.SelfGeneratedElectricity, 4),
                    GridImportKwh        = Math.Round(raw.ElectricityPurchased, 4),
                    BatteryChargedKwh    = Math.Round(raw.BatteryChargeEnergy, 4),
                    BatteryDischargedKwh = Math.Round(raw.BatteryDischargeEnergy, 4),
                    LoadKwh              = Math.Round(raw.LoadPowerConsumption, 4),
                });
            }
            catch (Exception ex)
            {
                Console.Error.WriteLine($"[AggregatedJsonParser] Skipping hourly line: {ex.Message}");
            }
        }

        Console.WriteLine($"[AggregatedJsonParser] Parsed {result.Count} hourly record(s)");
        return result;
    }

    /// <summary>
    /// Converts ISO date "yyyy-MM-dd" to device filename format "ddMMyyyy".
    /// </summary>
    public static String ToJsonFileName(String isoDate)
    {
        var d = DateOnly.ParseExact(isoDate, "yyyy-MM-dd");
        return d.ToString("ddMMyyyy") + ".json";
    }

    public static String ToJsonFileName(DateOnly date) => date.ToString("ddMMyyyy") + ".json";

    /// <summary>
    /// Tries to read an aggregated JSON file from the installation's S3 bucket.
    /// S3 key: DDMMYYYY.json (directly in bucket root).
    /// Returns file content or null if not found / error.
    /// </summary>
    public static async Task<String?> TryReadFromS3(Installation installation, String isoDate)
    {
        try
        {
            var fileName = ToJsonFileName(isoDate);
            var region   = new S3Region($"https://{installation.S3Region}.{installation.S3Provider}", ExoCmd.S3Credentials!);
            var bucket   = region.Bucket(installation.BucketName());
            var s3Url    = bucket.Path(fileName);

            return await s3Url.GetObjectAsString();
        }
        catch (Exception ex)
        {
            Console.Error.WriteLine($"[AggregatedJsonParser] S3 read failed for {isoDate}: {ex.Message}");
            return null;
        }
    }

    // --- JSON DTOs ---

    private sealed class HourlyJsonDto
    {
        public String   Type                     { get; set; } = "";
        public DateTime Timestamp                { get; set; }
        public Double   SelfGeneratedElectricity { get; set; }
        public Double   ElectricityPurchased     { get; set; }
        public Double   ElectricityFed           { get; set; }
        public Double   BatteryChargeEnergy      { get; set; }
        public Double   BatteryDischargeEnergy   { get; set; }
        public Double   LoadPowerConsumption     { get; set; }
    }

    private sealed class DailyJsonDto
    {
        public String   Type                          { get; set; } = "";
        public DateTime Timestamp                     { get; set; }
        public Double   DailySelfGeneratedElectricity { get; set; }
        public Double   DailyElectricityPurchased     { get; set; }
        public Double   DailyElectricityFed           { get; set; }
        public Double   BatteryDailyChargeEnergy      { get; set; }
        public Double   BatteryDailyDischargeEnergy   { get; set; }
        public Double   DailyLoadPowerConsumption     { get; set; }
    }
}