using MediaBrowser.Controller.Entities;
using MediaBrowser.Controller.IO;
using MediaBrowser.Controller.Resolvers;
using MediaBrowser.Common.Extensions;
using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;

namespace MediaBrowser.Controller.Library
{
    public class ItemController
    {
        //private BaseItem ResolveItem(ItemResolveEventArgs args)
        //{
        //    // Try first priority resolvers
        //    for (int i = 0; i < Kernel.Instance.EntityResolvers.Length; i++)
        //    {
        //        var item = Kernel.Instance.EntityResolvers[i].ResolvePath(args);

        //        if (item != null)
        //        {
        //            return item;
        //        }
        //    }

        //    return null;
        //}

        /// <summary>
        /// Resolves a path into a BaseItem
        /// </summary>
        public async Task<BaseItem> GetItem(string path, Folder parent = null, WIN32_FIND_DATA? fileInfo = null, bool allowInternetProviders = true)
        {
            ItemResolveEventArgs args = new ItemResolveEventArgs()
            {
                FileInfo = fileInfo ?? FileData.GetFileData(path),
                Parent = parent,
                Cancel = false,
                Path = path
            };

            // Gather child folder and files
            if (args.IsDirectory)
            {
                args.FileSystemChildren = FileData.GetFileSystemEntries(path, "*").ToArray();

                bool isVirtualFolder = parent != null && parent.IsRoot;
                args = FileSystemHelper.FilterChildFileSystemEntries(args, isVirtualFolder);
            }
            else
            {
                args.FileSystemChildren = new WIN32_FIND_DATA[] { };
            }


            // Fire BeginResolvePath to see if anyone wants to cancel this operation
            if (!EntityResolutionHelper.ShouldResolvePathContents(args))
            {
                return null;
            }

            BaseItem item = Kernel.Instance.ResolveItem(args);

            return item;
        }

        ///// <summary>
        ///// Finds child BaseItems for a given Folder
        ///// </summary>
        //private Task<BaseItem>[] GetChildren(Folder folder, WIN32_FIND_DATA[] fileSystemChildren, bool allowInternetProviders)
        //{
        //    Task<BaseItem>[] tasks = new Task<BaseItem>[fileSystemChildren.Length];

        //    for (int i = 0; i < fileSystemChildren.Length; i++)
        //    {
        //        var child = fileSystemChildren[i];

        //        tasks[i] = GetItem(child.Path, folder, child, allowInternetProviders: allowInternetProviders);
        //    }

        //    return tasks;
        //}

        ///// <summary>
        ///// Transforms shortcuts into their actual paths
        ///// </summary>
        //private WIN32_FIND_DATA[] FilterChildFileSystemEntries(WIN32_FIND_DATA[] fileSystemChildren, bool flattenShortcuts)
        //{
        //    WIN32_FIND_DATA[] returnArray = new WIN32_FIND_DATA[fileSystemChildren.Length];
        //    List<WIN32_FIND_DATA> resolvedShortcuts = new List<WIN32_FIND_DATA>();

        //    for (int i = 0; i < fileSystemChildren.Length; i++)
        //    {
        //        WIN32_FIND_DATA file = fileSystemChildren[i];

        //        // If it's a shortcut, resolve it
        //        if (Shortcut.IsShortcut(file.Path))
        //        {
        //            string newPath = Shortcut.ResolveShortcut(file.Path);
        //            WIN32_FIND_DATA newPathData = FileData.GetFileData(newPath);

        //            // Find out if the shortcut is pointing to a directory or file
        //            if (newPathData.IsDirectory)
        //            {
        //                // If we're flattening then get the shortcut's children

        //                if (flattenShortcuts)
        //                {
        //                    returnArray[i] = file;
        //                    WIN32_FIND_DATA[] newChildren = FileData.GetFileSystemEntries(newPath, "*").ToArray();

        //                    resolvedShortcuts.AddRange(FilterChildFileSystemEntries(newChildren, false));
        //                }
        //                else
        //                {
        //                    returnArray[i] = newPathData;
        //                }
        //            }
        //            else
        //            {
        //                returnArray[i] = newPathData;
        //            }
        //        }
        //        else
        //        {
        //            returnArray[i] = file;
        //        }
        //    }

        //    if (resolvedShortcuts.Count > 0)
        //    {
        //        resolvedShortcuts.InsertRange(0, returnArray);
        //        return resolvedShortcuts.ToArray();
        //    }
        //    else
        //    {
        //        return returnArray;
        //    }
        //}

        /// <summary>
        /// Gets a Person
        /// </summary>
        public Task<Person> GetPerson(string name)
        {
            return GetImagesByNameItem<Person>(Kernel.Instance.ApplicationPaths.PeoplePath, name);
        }

        /// <summary>
        /// Gets a Studio
        /// </summary>
        public Task<Studio> GetStudio(string name)
        {
            return GetImagesByNameItem<Studio>(Kernel.Instance.ApplicationPaths.StudioPath, name);
        }

        /// <summary>
        /// Gets a Genre
        /// </summary>
        public Task<Genre> GetGenre(string name)
        {
            return GetImagesByNameItem<Genre>(Kernel.Instance.ApplicationPaths.GenrePath, name);
        }

        /// <summary>
        /// Gets a Year
        /// </summary>
        public Task<Year> GetYear(int value)
        {
            return GetImagesByNameItem<Year>(Kernel.Instance.ApplicationPaths.YearPath, value.ToString());
        }

        private ConcurrentDictionary<string, object> ImagesByNameItemCache = new ConcurrentDictionary<string, object>(StringComparer.OrdinalIgnoreCase);

        /// <summary>
        /// Generically retrieves an IBN item
        /// </summary>
        private Task<T> GetImagesByNameItem<T>(string path, string name)
            where T : BaseEntity, new()
        {
            name = FileData.GetValidFilename(name);

            string key = Path.Combine(path, name);

            // Look for it in the cache, if it's not there, create it
            if (!ImagesByNameItemCache.ContainsKey(key))
            {
                ImagesByNameItemCache[key] = CreateImagesByNameItem<T>(path, name);
            }

            return ImagesByNameItemCache[key] as Task<T>;
        }

        /// <summary>
        /// Creates an IBN item based on a given path
        /// </summary>
        private async Task<T> CreateImagesByNameItem<T>(string path, string name)
            where T : BaseEntity, new()
        {
            T item = new T();

            item.Name = name;
            item.Id = path.GetMD5();

            if (!Directory.Exists(path))
            {
                Directory.CreateDirectory(path);
            }

            item.DateCreated = Directory.GetCreationTimeUtc(path);
            item.DateModified = Directory.GetLastWriteTimeUtc(path);

            ItemResolveEventArgs args = new ItemResolveEventArgs();
            args.FileInfo = FileData.GetFileData(path);
            args.FileSystemChildren = FileData.GetFileSystemEntries(path, "*").ToArray();

            await Kernel.Instance.ExecuteMetadataProviders(item).ConfigureAwait(false);

            return item;
        }
    }
}