using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using FinlyticCore.Dtos;
using FinlyticCore.Dtos.Simulation;
using FinlyticBackend.Util;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;

namespace FinlyticBackend.Controllers;

[ApiController]
[Authorize]
[Route("api/v1/simulation")]
public class SimulationController : ControllerBase
{
    private readonly BackendMqttBridge _mqttBridge;
    private readonly ILogger<SimulationController> _logger;

    public SimulationController(BackendMqttBridge mqttBridge, ILogger<SimulationController> logger)
    {
        _mqttBridge = mqttBridge;
        _logger = logger;
    }

    [HttpPost("run")]
    public async Task<IActionResult> RunBacktest([FromBody] BacktestRequestDto request)
    {
        if (request == null || string.IsNullOrWhiteSpace(request.Isin) || string.IsNullOrWhiteSpace(request.StrategyKey))
        {
            return BadRequest(new { Message = "ISIN and StrategyKey are required for backtesting." });
        }

        try
        {
            _logger.LogInformation("Starting backtest via REST for {Isin} ({StrategyKey}) on {Timeframe}", request.Isin, request.StrategyKey, request.Timeframe);

            var report = await _mqttBridge.SendRpcRequestAsync<BacktestReportDto, BacktestRequestDto>(
                "sim_RunBacktest",
                request,
                TimeSpan.FromSeconds(25)
            );

            if (report == null)
            {
                return StatusCode(504, new { Message = "Simulation service timed out or did not return a report." });
            }

            return Ok(report);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error running backtest for {Isin}", request.Isin);
            return StatusCode(500, new { Message = ex.Message });
        }
    }

    [HttpGet("matrix/{isin}")]
    public async Task<IActionResult> GetStrategyMatrix(string isin)
    {
        if (string.IsNullOrWhiteSpace(isin))
        {
            return BadRequest(new { Message = "ISIN is required." });
        }

        try
        {
            var matrix = await _mqttBridge.SendRpcRequestAsync<List<StrategyAssetReliabilityDto>, IsinRequest>(
                "sim_GetMatrixForAsset",
                new IsinRequest(isin, null, false),
                TimeSpan.FromSeconds(5)
            );

            return Ok(matrix ?? new List<StrategyAssetReliabilityDto>());
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error fetching strategy matrix for {Isin}", isin);
            return StatusCode(500, new { Message = ex.Message });
        }
    }

    /// <summary>
    /// Lightweight history of past backtest runs for an ISIN, optionally narrowed to one strategy - every run
    /// is already persisted server-side (<c>sim_RunBacktest</c>) but was previously only reachable indirectly
    /// via the reliability matrix, never queryable as a history in its own right.
    /// </summary>
    [HttpGet("history/{isin}")]
    public async Task<IActionResult> GetBacktestHistory(string isin, [FromQuery] string? strategyKey = null, [FromQuery] int limit = 20)
    {
        if (string.IsNullOrWhiteSpace(isin))
        {
            return BadRequest(new { Message = "ISIN is required." });
        }

        try
        {
            var history = await _mqttBridge.SendRpcRequestAsync<List<BacktestHistoryEntryDto>, GetBacktestHistoryRequest>(
                "sim_GetBacktestHistory",
                new GetBacktestHistoryRequest(isin, strategyKey, limit),
                TimeSpan.FromSeconds(5)
            );

            return Ok(history ?? new List<BacktestHistoryEntryDto>());
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error fetching backtest history for {Isin}", isin);
            return StatusCode(500, new { Message = ex.Message });
        }
    }

    /// <summary>Full report (trades + equity curve) for one specific past backtest run, for drilling into a history entry.</summary>
    [HttpGet("history/run/{runId:guid}")]
    public async Task<IActionResult> GetBacktestRunDetail(Guid runId)
    {
        try
        {
            var report = await _mqttBridge.SendRpcRequestAsync<BacktestReportDto, GetBacktestRunDetailRequest>(
                "sim_GetBacktestRunDetail",
                new GetBacktestRunDetailRequest(runId),
                TimeSpan.FromSeconds(5)
            );

            if (report == null)
            {
                return NotFound(new { Message = $"No backtest run found for RunId {runId}." });
            }

            return Ok(report);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error fetching backtest run detail for {RunId}", runId);
            return StatusCode(500, new { Message = ex.Message });
        }
    }

    /// <summary>Saved indicator-parameter profile for one (Isin, StrategyKey) pair, or 404 if none was ever saved.</summary>
    [HttpGet("parameters/{isin}/{strategyKey}")]
    public async Task<IActionResult> GetStrategyParameters(string isin, string strategyKey)
    {
        if (string.IsNullOrWhiteSpace(isin) || string.IsNullOrWhiteSpace(strategyKey))
        {
            return BadRequest(new { Message = "ISIN and StrategyKey are required." });
        }

        try
        {
            var profile = await _mqttBridge.SendRpcRequestAsync<StrategyParameterProfileDto, GetStrategyParametersRequest>(
                "sim_GetStrategyParameters",
                new GetStrategyParametersRequest(isin, strategyKey),
                TimeSpan.FromSeconds(5)
            );

            if (profile == null)
            {
                return NotFound(new { Message = $"No saved parameter profile for {isin}/{strategyKey}." });
            }

            return Ok(profile);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error fetching strategy parameters for {Isin}/{StrategyKey}", isin, strategyKey);
            return StatusCode(500, new { Message = ex.Message });
        }
    }

    /// <summary>Saves/updates a per-asset/per-strategy indicator-parameter profile for future backtests to reuse.</summary>
    [HttpPost("parameters")]
    public async Task<IActionResult> SaveStrategyParameters([FromBody] SaveStrategyParametersRequest request)
    {
        if (request == null || string.IsNullOrWhiteSpace(request.Isin) || string.IsNullOrWhiteSpace(request.StrategyKey))
        {
            return BadRequest(new { Message = "ISIN and StrategyKey are required." });
        }

        try
        {
            var profile = await _mqttBridge.SendRpcRequestAsync<StrategyParameterProfileDto, SaveStrategyParametersRequest>(
                "sim_SaveStrategyParameters",
                request,
                TimeSpan.FromSeconds(5)
            );

            if (profile == null)
            {
                return StatusCode(504, new { Message = "Simulation service timed out or did not confirm the save." });
            }

            return Ok(profile);
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "Error saving strategy parameters for {Isin}/{StrategyKey}", request.Isin, request.StrategyKey);
            return StatusCode(500, new { Message = ex.Message });
        }
    }
}