using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Jellyfin.Plugin.Floatplane.Channel;
using Jellyfin.Plugin.Floatplane.Playback;
using MediaBrowser.Common.Api;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Logging;

namespace Jellyfin.Plugin.Floatplane.Api;

/// <summary>Helpers for the dashboard configuration page (admin only).</summary>
[ApiController]
[Route("Floatplane")]
[Authorize(Policy = Policies.RequiresElevation)]
public class FloatplaneAdminController : ControllerBase
{
    private readonly FloatplaneApiClient _api;
    private readonly FloatplaneAuthService _auth;
    private readonly CatalogService _catalog;
    private readonly DeliveryResolver _delivery;
    private readonly ILogger<FloatplaneAdminController> _logger;

    public FloatplaneAdminController(FloatplaneApiClient api, FloatplaneAuthService auth, CatalogService catalog, DeliveryResolver delivery, ILogger<FloatplaneAdminController> logger)
    {
        _api = api;
        _auth = auth;
        _catalog = catalog;
        _delivery = delivery;
        _logger = logger;
    }

    // ───────────────────────────── OAuth device flow ─────────────────────────────

    /// <summary>Starts an OAuth device login with the given client id (saved to the configuration).</summary>
    [HttpPost("OAuth/Start")]
    public async Task<ActionResult<DeviceLoginStart>> StartOAuth([FromBody] OAuthStartRequest request)
    {
        var clientId = request.ClientId?.Trim() ?? string.Empty;
        if (clientId.Length == 0)
        {
            return BadRequest("Client id is empty");
        }

        try
        {
            var start = await _auth.StartDeviceLoginAsync(clientId, HttpContext.RequestAborted).ConfigureAwait(false);
            var cfg = Plugin.Instance?.Configuration;
            if (cfg != null && cfg.OAuthClientId != clientId)
            {
                cfg.OAuthClientId = clientId;
                Plugin.Instance!.SaveConfiguration();
            }

            start.DeviceCode = string.Empty;   // never hand the device code to the browser
            return start;
        }
        catch (FloatplaneApiException ex)
        {
            _logger.LogWarning("OAuth device start failed: {Error} {Message}", ex.ErrorName, ex.Message);
            return StatusCode(502, $"{ex.ErrorName}: {ex.Message}");
        }
    }

    /// <summary>Polls the pending device login once.</summary>
    [HttpGet("OAuth/Poll")]
    public async Task<ActionResult<DeviceLoginStatus>> PollOAuth()
    {
        var status = await _auth.PollDeviceLoginAsync(HttpContext.RequestAborted).ConfigureAwait(false);
        if (status.State == "done")
        {
            _catalog.Invalidate();
            try
            {
                var self = await _api.GetSelfAsync(HttpContext.RequestAborted).ConfigureAwait(false);
                var cfg = Plugin.Instance?.Configuration;
                if (cfg != null)
                {
                    cfg.SessionUsername = self.Username;
                    Plugin.Instance!.SaveConfiguration();
                }

                status.Message = "Logged in as " + self.Username;
            }
            catch (FloatplaneApiException ex)
            {
                status.Message = "Logged in, but user lookup failed: " + ex.Message;
            }
        }

        return status;
    }

    /// <summary>Drops the stored OAuth tokens.</summary>
    [HttpPost("OAuth/Logout")]
    public ActionResult<PluginStatus> LogoutOAuth()
    {
        FloatplaneAuthService.Logout();
        _catalog.Invalidate();
        return GetStatus();
    }

    /// <summary>Validates a session cookie (without saving it) and lists the subscriptions it has.</summary>
    [HttpPost("Session/Validate")]
    public async Task<ActionResult<SessionValidationResult>> ValidateSession([FromBody] SessionValidationRequest request)
    {
        var cookie = request.Cookie?.Trim() ?? string.Empty;
        if (cookie.StartsWith("sails.sid=", StringComparison.OrdinalIgnoreCase))
        {
            cookie = cookie["sails.sid=".Length..];
        }

        cookie = cookie.Trim().TrimEnd(';');
        if (cookie.Length == 0)
        {
            return new SessionValidationResult { Ok = false, Message = "Cookie is empty" };
        }

        try
        {
            var ct = HttpContext.RequestAborted;
            var self = await _api.GetSelfAsync(ct, cookie).ConfigureAwait(false);
            var subs = await _api.GetSubscriptionsAsync(ct, cookie).ConfigureAwait(false);
            return new SessionValidationResult
            {
                Ok = true,
                Username = self.Username,
                Cookie = cookie,
                Subscriptions = subs.Select(s => (s.Plan?.Title ?? "?") + " (" + s.Creator + ")").ToList(),
                Message = $"Logged in as {self.Username}, {subs.Count} active subscription(s)"
            };
        }
        catch (FloatplaneAuthException ex)
        {
            return new SessionValidationResult { Ok = false, Message = "Floatplane rejected the cookie: " + ex.Message };
        }
        catch (FloatplaneApiException ex)
        {
            return new SessionValidationResult { Ok = false, Message = "Floatplane error: " + ex.Message };
        }
    }

    /// <summary>Current plugin state for the settings page.</summary>
    [HttpGet("Status")]
    public ActionResult<PluginStatus> GetStatus()
    {
        return new PluginStatus
        {
            Version = typeof(Plugin).Assembly.GetName().Version?.ToString() ?? "?",
            HasSessionCookie = _api.HasSession,
            SessionKind = _api.SessionKind,
            OAuthClientId = Plugin.Instance?.Configuration.OAuthClientId ?? string.Empty,
            SessionState = _catalog.SessionState ?? "unknown",
            SessionUsername = Plugin.Instance?.Configuration.SessionUsername ?? string.Empty,
            LastError = _catalog.LastError,
            Generation = _catalog.Generation,
            LastRefresh = _catalog.LastRefresh == DateTimeOffset.MinValue ? null : _catalog.LastRefresh,
            Creators = _catalog.Creators.Select(c => new CreatorSummary
            {
                Id = c.Id,
                Title = c.Title,
                Urlname = c.Urlname,
                Channels = c.Channels.Select(ch => ch.Title).ToList()
            }).ToList(),
            CachedPostLists = _catalog.CachedPostListCount,
            CachedDeliveries = _delivery.CachedEntries
        };
    }

    /// <summary>Drops caches and reloads creators (post lists refill on browse).</summary>
    [HttpPost("Refresh")]
    public async Task<ActionResult<PluginStatus>> Refresh()
    {
        _catalog.Invalidate();
        await _catalog.GetCreatorsAsync(true, HttpContext.RequestAborted).ConfigureAwait(false);
        return GetStatus();
    }

    /// <summary>Runs a Floatplane search (public endpoint) — for mapping/testing the search API.</summary>
    [HttpGet("Search")]
    public async Task<ActionResult<List<SearchHit>>> Search(
        [FromQuery] string creatorId,
        [FromQuery] string? q,
        [FromQuery] string? channelId,
        [FromQuery] int limit = 20)
    {
        var posts = await _catalog.FetchPostsAsync(creatorId, channelId ?? string.Empty, Math.Clamp(limit, 1, 100), HttpContext.RequestAborted, q).ConfigureAwait(false);
        return posts.Select(p => new SearchHit
        {
            Id = p.Id,
            Title = p.Title,
            Channel = p.Channel?.Title ?? p.Channel?.Id,
            ReleaseDate = p.ReleaseDate,
            DurationSeconds = p.DurationSeconds,
            IsAccessible = p.IsAccessible,
            Thumbnail = p.Thumbnail?.BestPath(400)
        }).ToList();
    }

    /// <summary>Tags Floatplane knows for a creator (public endpoint).</summary>
    [HttpGet("Tags")]
    public Task<Dictionary<string, int>> Tags([FromQuery] string creatorId)
        => _api.GetTagsAsync(creatorId, HttpContext.RequestAborted);
}

public class OAuthStartRequest
{
    public string? ClientId { get; set; }
}

public class SessionValidationRequest
{
    public string? Cookie { get; set; }
}

public class SessionValidationResult
{
    public bool Ok { get; set; }

    public string? Username { get; set; }

    public string? Cookie { get; set; }

    public string? Message { get; set; }

    public List<string> Subscriptions { get; set; } = new();
}

public class PluginStatus
{
    public string Version { get; set; } = string.Empty;

    public bool HasSessionCookie { get; set; }

    /// <summary>"oauth", "cookie" or "none".</summary>
    public string SessionKind { get; set; } = string.Empty;

    public string OAuthClientId { get; set; } = string.Empty;

    public string SessionState { get; set; } = string.Empty;

    public string SessionUsername { get; set; } = string.Empty;

    public string? LastError { get; set; }

    public int Generation { get; set; }

    public DateTimeOffset? LastRefresh { get; set; }

    public List<CreatorSummary> Creators { get; set; } = new();

    public int CachedPostLists { get; set; }

    public int CachedDeliveries { get; set; }
}

public class CreatorSummary
{
    public string Id { get; set; } = string.Empty;

    public string Title { get; set; } = string.Empty;

    public string Urlname { get; set; } = string.Empty;

    public List<string> Channels { get; set; } = new();
}

public class SearchHit
{
    public string Id { get; set; } = string.Empty;

    public string Title { get; set; } = string.Empty;

    public string? Channel { get; set; }

    public DateTimeOffset? ReleaseDate { get; set; }

    public double DurationSeconds { get; set; }

    public bool IsAccessible { get; set; }

    public string? Thumbnail { get; set; }
}