using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Mvc;
using PlaylistShared.Api.Entities;
using PlaylistShared.Api.Services;
using System.Security.Claims;

namespace PlaylistShared.Api.Controllers;

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

    public AudioController(
        UserManager<ApplicationUser> userManager,
        YandexMusicService yandexService,
        SharedPlaylistService sharedService,
        JwtService jwtService)
    {
        _userManager = userManager;
        _yandexService = yandexService;
        _sharedService = sharedService;
        _jwtService = jwtService;
    }

    /// <summary>
    /// Потоковое воспроизведение трека из Яндекс.Музыки.
    /// </summary>
    /// <param name="trackId">ID трека (например, "21696942").</param>
    /// <param name="access_token">gwt пользователя</param>
    /// <param name="shared_id">ID расшаренного плейлиста</param>
    [HttpGet("track/{trackId}")]
    [AllowAnonymous]
    public async Task<IActionResult> StreamTrack(string trackId, [FromQuery] string? access_token = null, [FromQuery] string? shared_id = null)
    {
        var user = await GetUserFromToken(access_token);
        if (user == null) user = await GetUserFromSharedPlaylistId(shared_id);
        if (user == null) return Unauthorized();

        var streamUrl = await _yandexService.GetTrackFileUrlAsync(user, trackId);
        if (string.IsNullOrEmpty(streamUrl)) return NotFound();

        var httpClient = new HttpClient();
        var request = new HttpRequestMessage(HttpMethod.Get, streamUrl);

        // Пробрасываем Range-заголовок клиента к Яндекс.Музыке
        if (Request.Headers.ContainsKey("Range"))
        {
            request.Headers.Add("Range", Request.Headers["Range"].ToString());
        }
        var response = await httpClient.SendAsync(request, HttpCompletionOption.ResponseHeadersRead);

        // Если Яндекс.Музыка поддерживает range, пробрасываем статус 206
        Response.StatusCode = (int)response.StatusCode;
        Response.ContentType = response.Content.Headers.ContentType?.ToString() ?? "audio/mpeg";

        if (response.Content.Headers.Contains("Content-Range"))
            Response.Headers.Append("Content-Range", response.Content.Headers.ContentRange?.ToString());
        if (response.Headers.Contains("Accept-Ranges"))
            Response.Headers.Append("Accept-Ranges", response.Headers.AcceptRanges?.ToString());
        if (response.Content.Headers.Contains("Content-Length"))
            Response.Headers.Append("Content-Length", response.Content.Headers.ContentLength?.ToString());

        await response.Content.CopyToAsync(Response.Body);
        return new EmptyResult();
    }

    private async Task<ApplicationUser?> GetUserFromToken(string? token)
    {
        if (string.IsNullOrEmpty(token)) return null;

        var principal = _jwtService.ValidateToken(token);
        if (principal == null) return null;

        var userId = principal.FindFirst(ClaimTypes.NameIdentifier)?.Value;
        if (string.IsNullOrEmpty(userId)) return null;

        return await _userManager.FindByIdAsync(userId);
    }

    private async Task<ApplicationUser?> GetUserFromSharedPlaylistId(string? sharedId)
    {
        if (string.IsNullOrEmpty(sharedId)) return null;

        var playlist = await _sharedService.GetEntityByTokenAsync(sharedId);

        if (playlist == null) return null;

        if (!await _sharedService.CanPlayEveryoneAsync(playlist)) return null;

        return await _userManager.FindByIdAsync(playlist.CreatorUserId.ToString());

    }
}