//! \file       ArcCRM.cs
//! \date       Wed Oct 12 14:15:11 2016
//! \brief      Circus resource archive.
//
// Copyright (C) 2016 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.Collections.Generic;
using System.ComponentModel.Composition;
using System.IO;

namespace GameRes.Formats.Circus
{
    internal class CrmArchive : ArcFile
    {
        readonly IDictionary<uint, Entry> OffsetMap;

        public CrmArchive (ArcView arc, ArchiveFormat impl, ICollection<Entry> dir, IDictionary<uint, Entry> offset_map)
            : base (arc, impl, dir)
        {
            OffsetMap = offset_map;
        }

        internal Stream OpenByOffset (uint offset)
        {
            Entry entry;
            if (!OffsetMap.TryGetValue (offset, out entry))
                throw new FileNotFoundException();
            return OpenEntry (entry);
        }
    }

    [Export(typeof(ArchiveFormat))]
    public class CrmOpener : ArchiveFormat
    {
        public override string         Tag { get { return "CRM"; } }
        public override string Description { get { return "Circus image archive"; } }
        public override uint     Signature { get { return 0x42585243; } } // 'CRXB'
        public override bool  IsHierarchic { get { return false; } }
        public override bool      CanWrite { get { return false; } }

        public override ArcFile TryOpen (ArcView file)
        {
            int count = file.View.ReadInt32 (8);
            if (!IsSaneCount (count))
                return null;

            var offset_map = new SortedDictionary<uint, Entry>();
            int index_offset = 0x10;
            var dir = new List<Entry> (count);
            for (int i = 0; i < count; ++i)
            {
                uint offset = file.View.ReadUInt32 (index_offset);
                var name = file.View.ReadString (index_offset+8, 0x18);
                var entry = FormatCatalog.Instance.Create<Entry> (name);
                entry.Offset = offset;
                dir.Add (entry);
                offset_map[offset] = entry;
                index_offset += 0x20;
            }
            using (var iterator = offset_map.GetEnumerator())
            {
                if (iterator.MoveNext())
                {
                    for (;;)
                    {
                        var entry = iterator.Current.Value;
                        if (!iterator.MoveNext())
                        {
                            entry.Size = (uint)(file.MaxOffset - entry.Offset);
                            break;
                        }
                        entry.Size = (uint)(iterator.Current.Key - entry.Offset);
                    }
                }
            }
            return new CrmArchive (file, this, dir, offset_map);
        }
    }
}