using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using PlaylistShared.Api.Entities;
using PlaylistShared.Api.Extensions;
using PlaylistShared.Api.Services;
using PlaylistShared.Shared;
using PlaylistShared.Shared.DTO;
using PlaylistShared.Shared.Shared;
using YandexMusic.API.Models.Playlist;

[ApiController]
[Route("api/[controller]")]
public class SharedPlaylistController : ControllerBase
{
    private readonly SharedPlaylistService _sharedService;
    private readonly YandexMusicService _yandexService;
    private readonly UserManager<ApplicationUser> _userManager;
    private readonly TrackAdditionLogService _trackLogService;

    public SharedPlaylistController(
        SharedPlaylistService sharedService,
        YandexMusicService yandexService,
        UserManager<ApplicationUser> userManager,
        TrackAdditionLogService trackLogService)
    {
        _sharedService = sharedService;
        _yandexService = yandexService;
        _userManager = userManager;
        _trackLogService = trackLogService;
    }

    // GET /api/sharedplaylist/{token}
    [HttpGet("{token}")]
    public async Task<ActionResult<ApiResponse<SharedPlaylistDto>>> GetByToken(string token)
    {
        var playlist = await _sharedService.GetByTokenAsync(token);
        if (playlist == null)
            return NotFound(ApiResponse<SharedPlaylistDto>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден" }));

        var currentUserId = User.FindFirst(System.Security.Claims.ClaimTypes.NameIdentifier)?.Value;
        var userIdGuid = !string.IsNullOrEmpty(currentUserId) ? Guid.Parse(currentUserId) : (Guid?)null;

        // Проверка прав просмотра (требует доступа к сущности)
        var entity = await _sharedService.GetEntityByTokenAsync(token);
        if (entity == null || !await _sharedService.CanViewAsync(entity, userIdGuid))
            return Unauthorized(ApiResponse<SharedPlaylistDto>.Fail(new ErrorResponse { StatusCode = 401, Message = "Недостаточно прав" }));

        return Ok(ApiResponse<SharedPlaylistDto>.Ok(playlist));
    }

    // GET /api/sharedplaylist/{token}/tracks
    [HttpGet("{token}/tracks")]
    public async Task<ActionResult<ApiResponse<YandexPlaylistData>>> GetTracks(string token)
    {
        var currentUserId = User.GetUserIdOrNull();
        var playlist = await _sharedService.GetEntityByTokenAsync(token);
        if (playlist == null)
            return NotFound(ApiResponse<YandexPlaylistData>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден" }));

        if (!await _sharedService.CanViewAsync(playlist, currentUserId))
            return Unauthorized();

        var creator = await _userManager.FindByIdAsync(playlist.CreatorUserId.ToString());
        if (creator == null)
            return StatusCode(500, ApiResponse<YandexPlaylistData>.Fail(new ErrorResponse { StatusCode = 500, Message = "Владелец плейлиста не найден" }));

        var yandexPlaylist = await _yandexService.GetPlaylistAsync(creator, playlist.YandexPlaylistOwnerUid, playlist.YandexPlaylistKind);
        if (yandexPlaylist == null)
            return NotFound(ApiResponse<YandexPlaylistData>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден в Яндекс.Музыке" }));

        var dto = MapToYandexPlaylistData(yandexPlaylist);
        return Ok(ApiResponse<YandexPlaylistData>.Ok(dto));
    }

    // PUT /api/sharedplaylist/{token}/permissions
    [HttpPut("{token}/permissions")]
    [Authorize]
    public async Task<ActionResult<ApiResponse<SharedPlaylistDto>>> UpdatePermissions(string token, [FromBody] UpdatePermissionsDto dto)
    {
        var userId = User.GetUserId();
        var playlist = await _sharedService.GetEntityByTokenAsync(token);
        if (playlist == null)
            return NotFound(ApiResponse<SharedPlaylistDto>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден" }));

        if (playlist.CreatorUserId != userId)
            return Forbid();

        var updated = await _sharedService.UpdatePermissionsAsync(playlist.Id, dto);
        if (updated == null)
            return BadRequest(ApiResponse<SharedPlaylistDto>.Fail(new ErrorResponse { StatusCode = 400, Message = "Ошибка обновления прав" }));

        return Ok(ApiResponse<SharedPlaylistDto>.Ok(updated));
    }

    // POST /api/sharedplaylist/{token}/add-tracks
    [HttpPost("{token}/add-tracks")]
    public async Task<ActionResult<ApiResponse<object>>> AddTracks(string token, [FromBody] AddTracksRequest request)
    {
        var currentUserId = User.GetUserIdOrNull();
        var playlist = await _sharedService.GetEntityByTokenAsync(token);
        if (playlist == null)
            return NotFound(ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден" }));

        if (!await _sharedService.CanAddTrackAsync(playlist, currentUserId))
            return StatusCode(403, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 403, Message = "Недостаточно прав для добавления треков" }));

        var creator = await _userManager.FindByIdAsync(playlist.CreatorUserId.ToString());
        if (creator == null)
            return StatusCode(500, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 500, Message = "Владелец плейлиста не найден" }));

        var updatedPlaylist = await _yandexService.AddTracksAsync(creator, playlist.YandexPlaylistOwnerUid, playlist.YandexPlaylistKind, request.TrackIds);
        if (updatedPlaylist == null)
            return StatusCode(500, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 500, Message = "Ошибка при добавлении треков" }));

        return Ok(ApiResponse<object>.Ok(new { message = "Треки добавлены" }));
    }

    // POST /api/sharedplaylist/{token}/remove-tracks
    [HttpPost("{token}/remove-tracks")]
    public async Task<ActionResult<ApiResponse<object>>> RemoveTracks(string token, [FromBody] RemoveTracksRequest request)
    {
        var currentUserId = User.GetUserIdOrNull();
        var playlist = await _sharedService.GetEntityByTokenAsync(token);
        if (playlist == null)
            return NotFound(ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 404, Message = "Плейлист не найден" }));

        foreach (var trackId in request.TrackIds)
        {
            if (!await _sharedService.CanRemoveTrackAsync(playlist, currentUserId, trackId))
                return StatusCode(403, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 403, Message = $"Недостаточно прав для удаления трека {trackId}" }));
        }

        var creator = await _userManager.FindByIdAsync(playlist.CreatorUserId.ToString());
        if (creator == null)
            return StatusCode(500, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 500, Message = "Владелец плейлиста не найден" }));

        var updatedPlaylist = await _yandexService.RemoveTracksAsync(creator, playlist.YandexPlaylistOwnerUid, playlist.YandexPlaylistKind, request.TrackIds);
        if (updatedPlaylist == null)
            return StatusCode(500, ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 500, Message = "Ошибка при удалении треков" }));

        foreach (var trackId in request.TrackIds)
            await _trackLogService.RemoveLogsForTrackAsync(playlist.Id, trackId);

        return Ok(ApiResponse<object>.Ok(new { message = "Треки удалены" }));
    }

    // POST /api/sharedplaylist/{token}/add-track-by-link
    [HttpPost("{token}/add-track-by-link")]
    public async Task<ActionResult<ApiResponse<object>>> AddTrackByLink(string token, [FromBody] AddTrackByLinkRequest request)
    {
        var trackId = ExtractTrackIdFromLink(request.Link);
        if (string.IsNullOrEmpty(trackId))
            return BadRequest(ApiResponse<object>.Fail(new ErrorResponse { StatusCode = 400, Message = "Неверный формат ссылки" }));

        return await AddTracks(token, new AddTracksRequest { TrackIds = new List<string> { trackId } });
    }

    private string? ExtractTrackIdFromLink(string link)
    {
        var match = System.Text.RegularExpressions.Regex.Match(link, @"/track/(\d+)");
        return match.Success ? match.Groups[1].Value : null;
    }

    private YandexPlaylistData MapToYandexPlaylistData(YPlaylist playlist)
    {
        return new YandexPlaylistData
        {
            Title = playlist.Title ?? "",
            Description = playlist.Description ?? "",
            Tracks = playlist.Tracks?.Select(t => new YandexTrack
            {
                Id = t.Track?.Id ?? "",
                Title = t.Track?.Title ?? "",
                Artists = t.Track?.Artists?.Select(a => a.Name).ToList() ?? new List<string>(),
                DurationMs = (int)(t.Track?.DurationMs ?? 0),
                CoverUri = t.Track?.CoverUri ?? ""
            }).ToList() ?? new List<YandexTrack>()
        };
    }
}