//! \file       FormatCatalog.cs
//! \date       Wed Sep 16 22:51:11 2015
//! \brief      game resources formats catalog class.
//
// Copyright (C) 2014-2015 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//

using System;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.ComponentModel.Composition.Hosting;
using System.IO;
using System.Linq;
using GameRes.Collections;
using System.Runtime.Serialization.Formatters.Binary;

namespace GameRes
{
    public sealed class FormatCatalog
    {
        private static readonly FormatCatalog m_instance = new FormatCatalog();

        #pragma warning disable 649
        [ImportMany(typeof(ArchiveFormat))]
        private IEnumerable<ArchiveFormat>  m_arc_formats;
        [ImportMany(typeof(ImageFormat))]
        private IEnumerable<ImageFormat>    m_image_formats;
        [ImportMany(typeof(AudioFormat))]
        private IEnumerable<AudioFormat>    m_audio_formats;
        [ImportMany(typeof(ScriptFormat))]
        private IEnumerable<ScriptFormat>   m_script_formats;
        #pragma warning restore 649

        private MultiValueDictionary<string, IResource> m_extension_map = new MultiValueDictionary<string, IResource>();
        private MultiValueDictionary<uint, IResource> m_signature_map = new MultiValueDictionary<uint, IResource>();

        /// <summary> The only instance of this class.</summary>
        public static FormatCatalog       Instance      { get { return m_instance; } }

        public IEnumerable<ArchiveFormat> ArcFormats    { get { return m_arc_formats; } }
        public IEnumerable<ImageFormat>   ImageFormats  { get { return m_image_formats; } }
        public IEnumerable<AudioFormat>   AudioFormats  { get { return m_audio_formats; } }
        public IEnumerable<ScriptFormat>  ScriptFormats { get { return m_script_formats; } }

        public IEnumerable<IResource> Formats
        {
            get
            {
                return ((IEnumerable<IResource>)ArcFormats).Concat (ImageFormats).Concat (AudioFormats).Concat (ScriptFormats);
            }
        }

        public int CurrentSchemeVersion { get; private set; }
        public string          SchemeID { get { return "GARbroDB"; } }

        public Exception LastError { get; set; }

        public event ParametersRequestEventHandler  ParametersRequest;

        private FormatCatalog ()
        {
            //An aggregate catalog that combines multiple catalogs
            var catalog = new AggregateCatalog();
            //Adds all the parts found in the same assembly as the Program class
            catalog.Catalogs.Add (new AssemblyCatalog (typeof(FormatCatalog).Assembly));
            //Adds parts matching pattern found in the directory of the assembly
            catalog.Catalogs.Add (new DirectoryCatalog (Path.GetDirectoryName (System.Reflection.Assembly.GetExecutingAssembly().Location), "Arc*.dll"));

            //Create the CompositionContainer with the parts in the catalog
            var container = new CompositionContainer (catalog);

            //Fill the imports of this object
            container.ComposeParts (this);
            AddResourceImpl (m_image_formats);
            AddResourceImpl (m_arc_formats);
            AddResourceImpl (m_audio_formats);
            AddResourceImpl (m_script_formats);
        }

        private void AddResourceImpl (IEnumerable<IResource> formats)
        {
            foreach (var impl in formats)
            {
                foreach (var ext in impl.Extensions)
                {
                    m_extension_map.Add (ext.ToUpperInvariant(), impl);
                }
                foreach (var signature in impl.Signatures)
                {
                    m_signature_map.Add (signature, impl);
                }
            }
        }

        /// <summary>
        /// Look up filename in format registry by filename extension and return corresponding interfaces.
        /// if no formats available, return empty range.
        /// </summary>
        public IEnumerable<IResource> LookupFileName (string filename)
        {
            string ext = Path.GetExtension (filename);
            if (string.IsNullOrEmpty (ext))
                return Enumerable.Empty<IResource>();
            return LookupExtension (ext.TrimStart ('.'));
        }

        public IEnumerable<IResource> LookupExtension (string ext)
        {
            return m_extension_map.GetValues (ext.ToUpperInvariant(), true);
        }

        public IEnumerable<Type> LookupExtension<Type> (string ext) where Type : IResource
        {
            return LookupExtension (ext).OfType<Type>();
        }

        public IEnumerable<IResource> LookupSignature (uint signature)
        {
            return m_signature_map.GetValues (signature, true);
        }

        public IEnumerable<Type> LookupSignature<Type> (uint signature) where Type : IResource
        {
            return LookupSignature (signature).OfType<Type>();
        }

        /// <summary>
        /// Create GameRes.Entry corresponding to <paramref name="filename"/> extension.
        /// <exception cref="System.ArgumentException">May be thrown if filename contains invalid
        /// characters.</exception>
        /// </summary>
        public EntryType Create<EntryType> (string filename) where EntryType : Entry, new()
        {
            EntryType entry = null;
            var formats = LookupFileName (filename);
            if (formats.Any())
                entry = formats.First().Create<EntryType>();
            if (null == entry)
                entry = new EntryType();
            entry.Name = filename;
            return entry;
        }

        public string GetTypeFromName (string filename)
        {
            var formats = LookupFileName (filename);
            if (formats.Any())
                return formats.First().Type;
            return "";
        }

        public void InvokeParametersRequest (object source, ParametersRequestEventArgs args)
        {
            if (null != ParametersRequest)
                ParametersRequest (source, args);
        }

        /// <summary>
        /// Read first 4 bytes from stream and return them as 32-bit signature.
        /// </summary>
        public static uint ReadSignature (Stream file)
        {
            file.Position = 0;
            uint signature = (byte)file.ReadByte();
            signature |= (uint)file.ReadByte() << 8;
            signature |= (uint)file.ReadByte() << 16;
            signature |= (uint)file.ReadByte() << 24;
            return signature;
        }

        public void DeserializeScheme (Stream input)
        {
            var bin = new BinaryFormatter();
            var db = (SchemeDataBase)bin.Deserialize (input);
            if (db.Version <= CurrentSchemeVersion)
                return;

            foreach (var format in Formats)
            {
                ResourceScheme scheme;
                if (!db.SchemeMap.TryGetValue (format.Tag, out scheme))
                    continue;
                format.Scheme = scheme;
            }
            CurrentSchemeVersion = db.Version;
        }

        public void SerializeScheme (Stream output)
        {
            var db = new SchemeDataBase {
                Version = CurrentSchemeVersion,
                SchemeMap = new Dictionary<string, ResourceScheme>()
            };
            foreach (var format in Formats)
            {
                var scheme = format.Scheme;
                if (null != scheme)
                    db.SchemeMap[format.Tag] = scheme;
            }
            var bin = new BinaryFormatter();
            bin.Serialize (output, db);
        }
    }

    [Serializable]
    public class SchemeDataBase
    {
        public int Version;

        public Dictionary<string, ResourceScheme> SchemeMap;
    }
}