using System;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using eprintServer.DTOs;
using eprintServer.Entities;
using eprintServer.Enums;
using eprintServer.Requests;
using eprintServer.Responses;
using eprintServer.Services;

namespace eprintServer.Controllers;

[ApiController]
[Route("api/v1/oauth")]
public class OauthCallbackController : ControllerBase
{
    private readonly UserService _userService;
    private readonly TokenService _tokenService;
    private readonly GoogleOAuthService _googleOAuthService;
    private readonly FacebookOAuthService _facebookOAuthService;
    private readonly LinkedInOAuthService _linkedInOAuthService;

    public OauthCallbackController(
        UserService userService,
        TokenService tokenService,
        GoogleOAuthService googleOAuthService,
        FacebookOAuthService facebookOAuthService,
        LinkedInOAuthService linkedInOAuthService)
    {
        _userService = userService;
        _tokenService = tokenService;
        _googleOAuthService = googleOAuthService;
        _facebookOAuthService = facebookOAuthService;
        _linkedInOAuthService = linkedInOAuthService;
    }


    [HttpGet("google/callback")]
    public async Task<ActionResult<JwtResponse>> GoogleCallback([FromQuery] string code)
    {
        var (user, token, error) = await _googleOAuthService.HandleLoginCallbackAsync(code);

        if (user == null || token == null)
        {
            return Redirect($"https://etbaaonline.com/oauth/success?error={Uri.EscapeDataString(error ?? "Google sign-in failed.")}");
        }

        var result = await CreateAuthResponse(user, GetMinimalDeviceRequest(), Provider.GOOGLE, token);

        // Extract the JwtResponse from the result
        if (result.Result is OkObjectResult okResult && okResult.Value is JwtResponse jwtResponse)
        {
            var redirectUrl = $"https://etbaaonline.com/oauth/success" +
                              $"?token={Uri.EscapeDataString(jwtResponse.Token)}" +
                              $"&role={Uri.EscapeDataString(jwtResponse.Roles.ToString())}";

            return Redirect(redirectUrl);
        }

        return Redirect("https://etbaaonline.com/oauth/success?error=auth_failed");
    }
    [HttpGet("facebook/callback")]
    public async Task<ActionResult<JwtResponse>> FacebookCallback([FromQuery] string code)
    {
        var (user, token, error) = await _facebookOAuthService.HandleLoginCallbackAsync(code);

        if (user == null || token == null)
        {
            return Redirect($"https://etbaaonline.com/oauth/error?error={Uri.EscapeDataString(error ?? "Facebook sign-in failed.")}");
        }

        var result = await CreateAuthResponse(user, GetMinimalDeviceRequest(), Provider.FACEBOOK, token);

        if (result.Result is OkObjectResult okResult && okResult.Value is JwtResponse jwtResponse)
        {
            var redirectUrl = $"https://etbaaonline.com/oauth/success" +
                              $"?token={Uri.EscapeDataString(jwtResponse.Token)}" +
                              $"&role={Uri.EscapeDataString(jwtResponse.Roles.ToString())}";

            return Redirect(redirectUrl);
        }

        return Redirect("https://etbaaonline.com/oauth/error?error=auth_failed");
    }

    [HttpGet("linkedin/callback")]
    public async Task<ActionResult<JwtResponse>> LinkedInCallback([FromQuery] string code)
    {
        var (user, token, error) = await _linkedInOAuthService.HandleLoginCallbackAsync(code);

        if (user == null || token == null)
        {
            return Redirect($"https://etbaaonline.com/oauth/error?error={Uri.EscapeDataString(error ?? "LinkedIn sign-in failed.")}");
        }

        var result = await CreateAuthResponse(user, GetMinimalDeviceRequest(), Provider.LINKEDIN, token);

        if (result.Result is OkObjectResult okResult && okResult.Value is JwtResponse jwtResponse)
        {
            var redirectUrl = $"https://etbaaonline.com/oauth/success" +
                              $"?token={Uri.EscapeDataString(jwtResponse.Token)}" +
                              $"&role={Uri.EscapeDataString(jwtResponse.Roles.ToString())}";

            return Redirect(redirectUrl);
        }

        return Redirect("https://etbaaonline.com/oauth/error?error=auth_failed");
    }
    // --- Helper Methods ---

    // Create a minimal device request for OAuth logins where the client may not have provided full device info
    private SignInRequest GetMinimalDeviceRequest()
    {
        return new SignInRequest
        {
            DeviceType = "Web",
            DeviceId = "OAuth",
            Ip = HttpContext.Connection.RemoteIpAddress?.ToString()
        };
    }

    private async Task<ActionResult<JwtResponse>> CreateAuthResponse(User user, SignInRequest deviceRequest, Provider provider, string? existingToken = null)
    {
        var existingUser = await _userService.FindByEmailAsync(user.Email);

        if (existingUser == null)
        {
            var userCount = await _userService.GetUserCountAsync();
            var username = _userService.GenerateUsername(user.Email, userCount);

            var newUser = new User
            {
                Name = user.Email,
                Email = user.Email,
                Username = username,
                Password = "aze",
                Active = true,
                Provider = provider
            };

            existingUser = await _userService.SaveUserAsync(newUser);
        }

        // Use the DB user going forward
        user = existingUser;


        var accessToken = existingToken ?? _tokenService.CreateToken(user);
        var refreshToken = "placeholder-refresh-token";

        var device = new UserDevice
        {
            DeviceType = deviceRequest.DeviceType ?? "Unknown",
            DeviceId = deviceRequest.DeviceId ?? Guid.NewGuid().ToString(),
            Ip = deviceRequest.Ip,
            LastJwt = accessToken,
            PushNotificationToken = deviceRequest.Tokendevice
        };
        user.Device = device;
        var updatedUser = await _userService.UpdateUserAsync(user);

        if (updatedUser.Device == null)
        {
            // If device update fails for some reason (e.g., DB constraint), return an error
            return StatusCode(StatusCodes.Status406NotAcceptable, "Failed to save device information.");
        }

        var response = new JwtResponse(
            accessToken,
            refreshToken,
            user.Role,
            updatedUser.Device.DeviceId,
            updatedUser.Device.DeviceType,
            updatedUser.Device.Ip,
            DateTime.UtcNow.AddDays(7)
        );

        return Ok(response);
    }
}