using System;
using System.Collections.Generic;
using System.Text.Json;
using FinlyticCore.Database;
using FinlyticCore.Dtos.Simulation;
using FinlyticCore.Entities.Settings;
using FinlyticSimulation.Database.Entities;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;

namespace FinlyticSimulation.Database;

public class SimulationDbContext : DbContext, ISettingsDbContext
{
    private static readonly JsonSerializerOptions JsonOptions = new()
    {
        PropertyNameCaseInsensitive = true,
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
        WriteIndented = false
    };

    public SimulationDbContext(DbContextOptions<SimulationDbContext> options) : base(options)
    {
    }

    public DbSet<SettingEntity> DynamicSettings => Set<SettingEntity>();
    public DbSet<SimulationRunEntity> SimulationRuns => Set<SimulationRunEntity>();
    public DbSet<SimulationStrategyMatrixEntity> StrategyMatrix => Set<SimulationStrategyMatrixEntity>();
    public DbSet<SimulationStrategyParameterEntity> StrategyParameters => Set<SimulationStrategyParameterEntity>();

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        // 1. Settings Table
        modelBuilder.Entity<SettingEntity>(entity =>
        {
            entity.HasKey(e => e.Id);
            entity.HasIndex(e => e.Key).IsUnique();
        });

        // 2. Report JSONB Converter
        var reportConverter = new ValueConverter<BacktestReportDto, string>(
            v => JsonSerializer.Serialize(v, JsonOptions),
            v => JsonSerializer.Deserialize<BacktestReportDto>(v, JsonOptions) ?? new BacktestReportDto(
                Guid.Empty, "", "", "", "", DateTime.UtcNow, DateTime.UtcNow, 0, 0, 0, 0m, 0m, 0m, 0m, 0m, 0m, 0m, TimeSpan.Zero, new List<BacktestTradeDto>(), new List<EquityPointDto>())
        );

        // 3. Simulation Runs Table
        modelBuilder.Entity<SimulationRunEntity>(entity =>
        {
            entity.HasKey(e => e.Id);
            entity.HasIndex(e => new { e.Isin, e.StrategyKey, e.Timeframe });
            entity.HasIndex(e => e.CreatedAtUtc);

            entity.Property(e => e.ReportJson)
                .HasColumnType("jsonb")
                .HasConversion(reportConverter);
        });

        // 4. Strategy Matrix Table
        modelBuilder.Entity<SimulationStrategyMatrixEntity>(entity =>
        {
            entity.HasKey(e => new { e.Isin, e.StrategyKey, e.Timeframe });
            entity.HasIndex(e => new { e.Isin, e.IsApproved });
            entity.HasIndex(e => e.ReliabilityScore);
        });

        // 5. Saved Strategy Parameter Profiles Table
        var parametersConverter = new ValueConverter<Dictionary<string, decimal>, string>(
            v => JsonSerializer.Serialize(v, JsonOptions),
            v => JsonSerializer.Deserialize<Dictionary<string, decimal>>(v, JsonOptions) ?? new Dictionary<string, decimal>()
        );

        modelBuilder.Entity<SimulationStrategyParameterEntity>(entity =>
        {
            entity.HasKey(e => new { e.Isin, e.StrategyKey });

            entity.Property(e => e.Parameters)
                .HasColumnType("jsonb")
                .HasConversion(parametersConverter);
        });
    }
}

public class SimulationDbContextFactory : IDesignTimeDbContextFactory<SimulationDbContext>
{
    public SimulationDbContext CreateDbContext(string[] args)
    {
        var optionsBuilder = new DbContextOptionsBuilder<SimulationDbContext>();
        optionsBuilder.UseNpgsql("Host=localhost;Database=finlytic_simulation;Username=postgres;Password=postgres");
        return new SimulationDbContext(optionsBuilder.Options);
    }
}