using Microsoft.Extensions.Logging;
using Roadie.Library.Caching;
using Roadie.Library.Configuration;
using Roadie.Library.Data;
using Roadie.Library.Encoding;
using Roadie.Library.Engines;
using Roadie.Library.Extensions;
using Roadie.Library.Factories;
using Roadie.Library.FilePlugins;
using Roadie.Library.MetaData.Audio;
using Roadie.Library.MetaData.ID3Tags;
using Roadie.Library.Utility;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace Roadie.Library.Processors
{
    public sealed class FolderProcessor : ProcessorBase
    {
        private readonly FileProcessor _fileProcessor;
        public int? ProcessLimit { get; set; }

        private FileProcessor FileProcessor
        {
            get
            {
                return this._fileProcessor;
            }
        }

        public FolderProcessor(IRoadieSettings configuration, IHttpEncoder httpEncoder, string destinationRoot, IRoadieDbContext context, ICacheManager cacheManager, ILogger logger, IArtistLookupEngine artistLookupEngine, IArtistFactory artistFactory, IReleaseFactory releaseFactory, IImageFactory imageFactory, IReleaseLookupEngine releaseLookupEngine, IAudioMetaDataHelper audioMetaDataHelper)
            : base(configuration, httpEncoder, destinationRoot, context, cacheManager, logger, artistLookupEngine, artistFactory, releaseFactory, imageFactory, releaseLookupEngine, audioMetaDataHelper)
        {
            SimpleContract.Requires<ArgumentNullException>(!string.IsNullOrEmpty(destinationRoot), "Invalid Destination Folder");
            this._fileProcessor = new FileProcessor(configuration, httpEncoder, destinationRoot, context, cacheManager, logger, artistLookupEngine, artistFactory, releaseFactory, imageFactory, releaseLookupEngine, audioMetaDataHelper);
        }

        public static OperationResult<bool> DeleteEmptyFolders(DirectoryInfo processingFolder, ILogger logger)
        {
            var result = new OperationResult<bool>();
            try
            {
                result.IsSuccess = FolderPathHelper.DeleteEmptyFolders(processingFolder);
            }
            catch (Exception ex)
            {
                logger.LogError(ex, string.Format("Error Deleting Empty Folder [{0}] Error [{1}]", processingFolder.FullName, ex.Serialize()));
            }
            return result;
        }

        public async Task<OperationResult<bool>> Process(DirectoryInfo folder, bool doJustInfo, int? submissionId = null)
        {
            var sw = new Stopwatch();
            sw.Start();
            await this.PreProcessFolder(folder, doJustInfo);
            int processedFiles = 0;
            var pluginResultInfos = new List<PluginResultInfo>();
            var errors = new List<string>();

            this.FileProcessor.SubmissionId = submissionId;

            foreach (var file in Directory.EnumerateFiles(folder.FullName, "*.*", SearchOption.AllDirectories).ToArray())
            {
                var operation = await this.FileProcessor.Process(file, doJustInfo);
                if (operation != null && operation.AdditionalData != null && operation.AdditionalData.ContainsKey(PluginResultInfo.AdditionalDataKeyPluginResultInfo))
                {
                    pluginResultInfos.Add(operation.AdditionalData[PluginResultInfo.AdditionalDataKeyPluginResultInfo] as PluginResultInfo);
                }
                if (operation == null)
                {
                    var fileExtensionsToDelete = this.Configuration.FileExtensionsToDelete ?? new string[0];
                    if (fileExtensionsToDelete.Any(x => x.Equals(Path.GetExtension(file), StringComparison.OrdinalIgnoreCase)))
                    {
                        if (!doJustInfo)
                        {
                            if (!Path.GetFileNameWithoutExtension(file).ToLower().Equals("cover"))
                            {
                                File.Delete(file);
                                this.Logger.LogInformation("x Deleted File [{0}], Was foud in in FileExtensionsToDelete", file);
                            }
                        }
                    }
                }
                processedFiles++;
                if (this.ProcessLimit.HasValue && processedFiles > this.ProcessLimit.Value)
                {
                    break;
                }
            }
            await this.PostProcessFolder(folder, pluginResultInfos, doJustInfo);
            sw.Stop();
            this.Logger.LogInformation("** Completed! Processed Folder [{0}]: Processed Files [{1}] : Elapsed Time [{2}]", folder.FullName.ToString(), processedFiles, sw.Elapsed);
            return new OperationResult<bool>
            {
                IsSuccess = !errors.Any(),
                AdditionalData = new Dictionary<string, object> {
                    { "processedFiles", processedFiles },
                    { "newArtists",  this.ArtistLookupEngine.AddedArtistIds.Count() },
                    { "newReleases", this.ReleaseLookupEngine.AddedReleaseIds.Count() },
                    { "newTracks",  this.ReleaseFactory.AddedTrackIds.Count() }
                },
                OperationTime = sw.ElapsedMilliseconds
            };
        }

        /// <summary>
        /// Perform any operations to the given folder and the plugin results after processing
        /// </summary>
        private async Task<bool> PostProcessFolder(DirectoryInfo inboundFolder, IEnumerable<PluginResultInfo> pluginResults, bool doJustInfo)
        {
            SimpleContract.Requires<ArgumentNullException>(inboundFolder != null, "Invalid InboundFolder");
            if (!doJustInfo)
            {
                FolderProcessor.DeleteEmptyFolders(inboundFolder, this.Logger);
                
            }
            if (pluginResults != null)
            {
                foreach (var releasesInfo in pluginResults.GroupBy(x => x.ReleaseId).Select(x => x.First()))
                {
                    await this.ReleaseFactory.ScanReleaseFolder(releasesInfo.ReleaseId, this.DestinationRoot, doJustInfo);
                }
            }
            return true;
        }

        /// <summary>
        /// Perform any operations to the given folder before processing
        /// </summary>
        private Task<bool> PreProcessFolder(DirectoryInfo inboundFolder, bool doJustInfo = false)
        {
            return Task.FromResult(true);
        }
    }
}