using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using System.Web.Http;
using System.Web.Http.Controllers;
using System.Web.Http.Filters;
using System.Xml.Linq;
using Jackett.Common;
using Jackett.Common.Indexers;
using Jackett.Common.Indexers.Meta;
using Jackett.Common.Models;
using Jackett.Common.Models.DTO;
using Jackett.Common.Services.Interfaces;
using Jackett.Common.Utils;
using NLog;

namespace Jackett.Controllers
{
    public class RequiresApiKeyAttribute : AuthorizationFilterAttribute
    {
        public override void OnAuthorization(HttpActionContext actionContext)
        {
            var validApiKey = Engine.ServerConfig.APIKey;
            var queryParams = actionContext.Request.GetQueryNameValuePairs();
            var queryApiKey = queryParams.Where(x => x.Key == "apikey" || x.Key == "passkey").Select(x => x.Value).FirstOrDefault();

#if DEBUG
            if (Debugger.IsAttached)
                return;
#endif
            if (queryApiKey != validApiKey)
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.Unauthorized, 100, $"Invalid API Key");
        }
    }

    public class RequiresConfiguredIndexerAttribute : ActionFilterAttribute
    {
        public override void OnActionExecuting(HttpActionContext actionContext)
        {
            var controller = actionContext.ControllerContext.Controller;
            if (!(controller is IIndexerController))
                return;

            var indexerController = controller as IIndexerController;

            var parameters = actionContext.RequestContext.RouteData.Values;

            if (!parameters.ContainsKey("indexerId"))
            {
                indexerController.CurrentIndexer = null;
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 200, $"indexer is not specified");
                return;
            }

            var indexerId = parameters["indexerId"] as string;
            if (indexerId.IsNullOrEmptyOrWhitespace())
            {
                indexerController.CurrentIndexer = null;
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not specified (empty value)");
                return;
            }

            var indexerService = indexerController.IndexerService;
            var indexer = indexerService.GetIndexer(indexerId);

            if (indexer == null)
            {
                indexerController.CurrentIndexer = null;
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not supported");
                return;
            }

            if (!indexer.IsConfigured)
            {
                indexerController.CurrentIndexer = null;
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotFound, 201, $"Indexer is not configured");
                return;
            }

            indexerController.CurrentIndexer = indexer;
        }
    }

    public class RequiresValidQueryAttribute : RequiresConfiguredIndexerAttribute
    {
        public override void OnActionExecuting(HttpActionContext actionContext)
        {
            base.OnActionExecuting(actionContext);
            if (actionContext.Response != null)
                return;

            var controller = actionContext.ControllerContext.Controller;
            if (!(controller is IResultController))
                return;

            var resultController = controller as IResultController;

            var query = actionContext.ActionArguments.First().Value;
            var queryType = query.GetType();
            var converter = queryType.GetMethod("ToTorznabQuery", System.Reflection.BindingFlags.Static | System.Reflection.BindingFlags.Public);
            if (converter == null)
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.BadRequest, 900, $"ToTorznabQuery() not found");
            var converted = converter.Invoke(null, new object[] { query });
            var torznabQuery = converted as TorznabQuery;
            resultController.CurrentQuery = torznabQuery;

            if (queryType == typeof(ApiSearch)) // Skip CanHandleQuery() check for manual search (CurrentIndexer isn't used during manul search)
                return;

            if (!resultController.CurrentIndexer.CanHandleQuery(resultController.CurrentQuery))
                actionContext.Response = ResultsController.GetErrorHttpResponseMessage(actionContext, HttpStatusCode.NotImplemented, 201, $"{resultController.CurrentIndexer.ID} does not support the requested query. Please check the capabilities (t=caps) and make sure the search mode and categories are supported.");
        }
    }

    public class JsonResponseAttribute : ActionFilterAttribute
    {
        public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
        {
            base.OnActionExecuted(actionExecutedContext);

            if (actionExecutedContext.Exception != null)
                throw new Exception("Error while executing request", actionExecutedContext.Exception);

            var content = actionExecutedContext.Response.Content as ObjectContent;
            actionExecutedContext.Response.Content = new JsonContent(content.Value);
        }
    }

    public interface IResultController : IIndexerController
    {
        TorznabQuery CurrentQuery { get; set; }
    }

    [AllowAnonymous]
    [JackettAPINoCache]
    [RoutePrefix("api/v2.0/indexers")]
    [RequiresApiKey]
    [RequiresValidQuery]
    public class ResultsController : ApiController, IResultController
    {
        public IIndexerManagerService IndexerService { get; private set; }
        public IIndexer CurrentIndexer { get; set; }
        public TorznabQuery CurrentQuery { get; set; }

        public ResultsController(IIndexerManagerService indexerManagerService, IServerService ss, ICacheService c, Logger logger)
        {
            IndexerService = indexerManagerService;
            serverService = ss;
            cacheService = c;
            this.logger = logger;
        }

        [HttpGet]
        public async Task<ManualSearchResult> Results([FromUri]ApiSearch request)
        {
            var manualResult = new ManualSearchResult();
            var trackers = IndexerService.GetAllIndexers().Where(t => t.IsConfigured);
            if (request.Tracker != null)
                trackers = trackers.Where(t => request.Tracker.Contains(t.ID));
            trackers = trackers.Where(t => t.CanHandleQuery(CurrentQuery));

            var tasks = trackers.ToList().Select(t => t.ResultsForQuery(CurrentQuery)).ToList();
            try
            {
                var aggregateTask = Task.WhenAll(tasks);
                await aggregateTask;
            }
            catch (AggregateException aex)
            {
                foreach (var ex in aex.InnerExceptions)
                {
                    logger.Error(ex);
                }
            }
            catch (Exception ex)
            {
                logger.Error(ex);
            }

            manualResult.Indexers = tasks.Select(t =>
            {
                var resultIndexer = new ManualSearchResultIndexer();
                IIndexer indexer = null;
                if (t.Status == TaskStatus.RanToCompletion)
                {
                    resultIndexer.Status = ManualSearchResultIndexerStatus.OK;
                    resultIndexer.Results = t.Result.Releases.Count();
                    resultIndexer.Error = null;
                    indexer = t.Result.Indexer;
                }
                else if (t.Exception.InnerException is IndexerException)
                {
                    resultIndexer.Status = ManualSearchResultIndexerStatus.Error;
                    resultIndexer.Results = 0;
                    resultIndexer.Error = ((IndexerException)t.Exception.InnerException).ToString();
                    indexer = ((IndexerException)t.Exception.InnerException).Indexer;
                }
                else
                {
                    resultIndexer.Status = ManualSearchResultIndexerStatus.Unknown;
                    resultIndexer.Results = 0;
                    resultIndexer.Error = null;
                }

                if (indexer != null)
                {
                    resultIndexer.ID = indexer.ID;
                    resultIndexer.Name = indexer.DisplayName;
                }
                return resultIndexer;
            }).ToList();

            manualResult.Results = tasks.Where(t => t.Status == TaskStatus.RanToCompletion).Where(t => t.Result.Releases.Count() > 0).SelectMany(t =>
            {
                var searchResults = t.Result.Releases;
                var indexer = t.Result.Indexer;
                cacheService.CacheRssResults(indexer, searchResults);

                return searchResults.Select(result =>
                {
                    var item = AutoMapper.Mapper.Map<TrackerCacheResult>(result);
                    item.Tracker = indexer.DisplayName;
                    item.TrackerId = indexer.ID;
                    item.Peers = item.Peers - item.Seeders; // Use peers as leechers

                    return item;
                });
            }).OrderByDescending(d => d.PublishDate).ToList();

            ConfigureCacheResults(manualResult.Results);

            logger.Info(string.Format("Manual search for \"{0}\" on {1} with {2} results.", CurrentQuery.SanitizedSearchTerm, string.Join(", ", manualResult.Indexers.Select(i => i.ID)), manualResult.Results.Count()));
            return manualResult;
        }

        [HttpGet]
        public async Task<IHttpActionResult> Torznab([FromUri]Common.Models.DTO.TorznabRequest request)
        {
            if (string.Equals(CurrentQuery.QueryType, "caps", StringComparison.InvariantCultureIgnoreCase))
            {
                return ResponseMessage(new HttpResponseMessage()
                {
                    Content = new StringContent(CurrentIndexer.TorznabCaps.ToXml(), Encoding.UTF8, "application/xml")
                });
            }

            // indexers - returns a list of all included indexers (meta indexers only)
            if (string.Equals(CurrentQuery.QueryType, "indexers", StringComparison.InvariantCultureIgnoreCase))
            {
                if (!(CurrentIndexer is BaseMetaIndexer)) // shouldn't be needed because CanHandleQuery should return false
                {
                    logger.Warn($"A search request with t=indexers from {Request.GetOwinContext().Request.RemoteIpAddress} was made but the indexer {CurrentIndexer.DisplayName} isn't a meta indexer.");
                    return GetErrorXML(203, "Function Not Available: this isn't a meta indexer");
                }
                var CurrentBaseMetaIndexer = (BaseMetaIndexer)CurrentIndexer;
                var indexers = CurrentBaseMetaIndexer.Indexers;
                if (string.Equals(request.configured, "true", StringComparison.InvariantCultureIgnoreCase))
                    indexers = indexers.Where(i => i.IsConfigured);
                else if (string.Equals(request.configured, "false", StringComparison.InvariantCultureIgnoreCase))
                    indexers = indexers.Where(i => !i.IsConfigured);

                var xdoc = new XDocument(
                    new XDeclaration("1.0", "UTF-8", null),
                    new XElement("indexers",
                        from i in indexers
                        select new XElement("indexer",
                            new XAttribute("id", i.ID),
                            new XAttribute("configured", i.IsConfigured),
                            new XElement("title", i.DisplayName),
                            new XElement("description", i.DisplayDescription),
                            new XElement("link", i.SiteLink),
                            new XElement("language", i.Language),
                            new XElement("type", i.Type),
                            i.TorznabCaps.GetXDocument().FirstNode
                        )
                    )
                );

                return ResponseMessage(new HttpResponseMessage()
                {
                    Content = new StringContent(xdoc.Declaration.ToString() + Environment.NewLine + xdoc.ToString(), Encoding.UTF8, "application/xml")
                });
            }

            if (CurrentQuery.ImdbID != null)
            {
                /* We should allow this (helpful in case of aggregate idnexers)
                if (!string.IsNullOrEmpty(CurrentQuery.SearchTerm))
                {
                    logger.Warn($"A search request from {Request.GetOwinContext().Request.RemoteIpAddress} was made containing q and imdbid.");
                    return GetErrorXML(201, "Incorrect parameter: please specify either imdbid or q");
                }
                */

                CurrentQuery.ImdbID = ParseUtil.GetFullImdbID(CurrentQuery.ImdbID); // normalize ImdbID
                if (CurrentQuery.ImdbID == null)
                {
                    logger.Warn($"A search request from {Request.GetOwinContext().Request.RemoteIpAddress} was made with an invalid imdbid.");
                    return GetErrorXML(201, "Incorrect parameter: invalid imdbid format");
                }

                if (!CurrentIndexer.TorznabCaps.SupportsImdbSearch)
                {
                    logger.Warn($"A search request with imdbid from {Request.GetOwinContext().Request.RemoteIpAddress} was made but the indexer {CurrentIndexer.DisplayName} doesn't support it.");
                    return GetErrorXML(203, "Function Not Available: imdbid is not supported by this indexer");
                }
            }

            try
            {
                var result = await CurrentIndexer.ResultsForQuery(CurrentQuery);

                // Some trackers do not support multiple category filtering so filter the releases that match manually.
                int? newItemCount = null;

                // Cache non query results
                if (string.IsNullOrEmpty(CurrentQuery.SanitizedSearchTerm))
                {
                    newItemCount = cacheService.GetNewItemCount(CurrentIndexer, result.Releases);
                    cacheService.CacheRssResults(CurrentIndexer, result.Releases);
                }

                // Log info
                var logBuilder = new StringBuilder();
                if (newItemCount != null)
                {
                    logBuilder.AppendFormat("Found {0} ({1} new) releases from {2}", result.Releases.Count(), newItemCount, CurrentIndexer.DisplayName);
                }
                else
                {
                    logBuilder.AppendFormat("Found {0} releases from {1}", result.Releases.Count(), CurrentIndexer.DisplayName);
                }

                if (!string.IsNullOrWhiteSpace(CurrentQuery.SanitizedSearchTerm))
                {
                    logBuilder.AppendFormat(" for: {0}", CurrentQuery.GetQueryString());
                }

                logger.Info(logBuilder.ToString());

                var serverUrl = serverService.GetServerUrl(Request);
                var resultPage = new ResultPage(new ChannelInfo
                {
                    Title = CurrentIndexer.DisplayName,
                    Description = CurrentIndexer.DisplayDescription,
                    Link = new Uri(CurrentIndexer.SiteLink),
                    ImageUrl = new Uri(serverUrl + "logos/" + CurrentIndexer.ID + ".png"),
                    ImageTitle = CurrentIndexer.DisplayName,
                    ImageLink = new Uri(CurrentIndexer.SiteLink),
                    ImageDescription = CurrentIndexer.DisplayName
                });

                var proxiedReleases = result.Releases.Select(r => AutoMapper.Mapper.Map<ReleaseInfo>(r)).Select(r =>
                {
                    r.Link = serverService.ConvertToProxyLink(r.Link, serverUrl, r.Origin.ID, "dl", r.Title);
                    return r;
                });

                resultPage.Releases = proxiedReleases.ToList();

                var xml = resultPage.ToXml(new Uri(serverUrl));
                // Force the return as XML
                return ResponseMessage(new HttpResponseMessage()
                {
                    Content = new StringContent(xml, Encoding.UTF8, "application/rss+xml")
                });
            }
            catch (Exception e)
            {
                Engine.Logger.Error(e);
                return GetErrorXML(900, e.Message);
            }
        }

        static public HttpResponseMessage GetErrorHttpResponseMessage(HttpActionContext actionContext, HttpStatusCode status, int torznabCode, string description)
        {
            var parameters = actionContext.RequestContext.RouteData.Values;
            var action = parameters["action"] as string;

            if (action == "torznab")
            {
                return GetErrorXMLHttpResponseMessage(torznabCode, description);
            }
            else
            {
                return actionContext.Request.CreateErrorResponse(status, description);
            }
        }

        static public HttpResponseMessage GetErrorXMLHttpResponseMessage(int code, string description)
        {
            var xdoc = new XDocument(
                new XDeclaration("1.0", "UTF-8", null),
                new XElement("error",
                    new XAttribute("code", code.ToString()),
                    new XAttribute("description", description)
                )
            );

            var xml = xdoc.Declaration.ToString() + Environment.NewLine + xdoc.ToString();

            return new HttpResponseMessage()
            {
                Content = new StringContent(xml, Encoding.UTF8, "application/xml")
            };
        }

        public IHttpActionResult GetErrorXML(int code, string description)
        {
            return ResponseMessage(GetErrorXMLHttpResponseMessage(code, description));
        }

        [HttpGet]
        [JsonResponse]
        public async Task<TorrentPotatoResponse> Potato([FromUri]TorrentPotatoRequest request)
        {
            var result = await CurrentIndexer.ResultsForQuery(CurrentQuery);

            // Cache non query results
            if (string.IsNullOrEmpty(CurrentQuery.SanitizedSearchTerm))
                cacheService.CacheRssResults(CurrentIndexer, result.Releases);

            // Log info
            if (string.IsNullOrWhiteSpace(CurrentQuery.SanitizedSearchTerm))
                logger.Info($"Found {result.Releases.Count()} torrentpotato releases from {CurrentIndexer.DisplayName}");
            else
                logger.Info($"Found {result.Releases.Count()} torrentpotato releases from {CurrentIndexer.DisplayName} for: {CurrentQuery.GetQueryString()}");

            var serverUrl = serverService.GetServerUrl(Request);
            var potatoReleases = result.Releases.Where(r => r.Link != null || r.MagnetUri != null).Select(r =>
            {
                var release = AutoMapper.Mapper.Map<ReleaseInfo>(r);
                release.Link = serverService.ConvertToProxyLink(release.Link, serverUrl, CurrentIndexer.ID, "dl", release.Title);
                var item = new TorrentPotatoResponseItem()
                {
                    release_name = release.Title + "[" + CurrentIndexer.DisplayName + "]", // Suffix the indexer so we can see which tracker we are using in CPS as it just says torrentpotato >.>
                    torrent_id = release.Guid.ToString(),
                    details_url = release.Comments.ToString(),
                    download_url = (release.Link != null ? release.Link.ToString() : release.MagnetUri.ToString()),
                    imdb_id = release.Imdb.HasValue ? ParseUtil.GetFullImdbID("tt" + release.Imdb) : null,
                    freeleech = (release.DownloadVolumeFactor == 0 ? true : false),
                    type = "movie",
                    size = (long)release.Size / (1024 * 1024), // This is in MB
                    leechers = (release.Peers ?? -1) - (release.Seeders ?? 0),
                    seeders = release.Seeders ?? -1,
                    publish_date = r.PublishDate == DateTime.MinValue ? null : release.PublishDate.ToUniversalTime().ToString("s")
                };
                return item;
            });

            var potatoResponse = new TorrentPotatoResponse()
            {
                results = potatoReleases.ToList()
            };

            return potatoResponse;
        }

        private void ConfigureCacheResults(IEnumerable<TrackerCacheResult> results)
        {
            var serverUrl = serverService.GetServerUrl(Request);
            foreach (var result in results)
            {
                var link = result.Link;
                var file = StringUtil.MakeValidFileName(result.Title, '_', false);
                result.Link = serverService.ConvertToProxyLink(link, serverUrl, result.TrackerId, "dl", file);
                if (!string.IsNullOrWhiteSpace(Engine.ServerConfig.BlackholeDir))
                {
                    if (result.Link != null)
                        result.BlackholeLink = serverService.ConvertToProxyLink(link, serverUrl, result.TrackerId, "bh", file);
                    else if (result.MagnetUri != null)
                        result.BlackholeLink = serverService.ConvertToProxyLink(result.MagnetUri, serverUrl, result.TrackerId, "bh", file);
                }

            }
        }

        private Logger logger;
        private IServerService serverService;
        private ICacheService cacheService;
    }
}