// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Info.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Apple DOS filesystem plugin.
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies the Apple DOS filesystem and shows information.
//
// --[ License ] --------------------------------------------------------------
//
//     This library is free software; you can redistribute it and/or modify
//     it under the terms of the GNU Lesser General Public License as
//     published by the Free Software Foundation; either version 2.1 of the
//     License, or (at your option) any later version.
//
//     This library is distributed in the hope that it will be useful, but
//     WITHOUT ANY WARRANTY; without even the implied warranty of
//     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
//     Lesser General Public License for more details.
//
//     You should have received a copy of the GNU Lesser General Public
//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2017 Natalia Portillo
// ****************************************************************************/

using System;
using System.Runtime.InteropServices;
using System.Text;
using DiscImageChef.ImagePlugins;

namespace DiscImageChef.Filesystems.AppleDOS
{
    public partial class AppleDOS : Filesystem
    {
        public override bool Identify(ImagePlugin imagePlugin, ulong partitionStart, ulong partitionEnd)
        {
            if(imagePlugin.ImageInfo.sectors != 455 && imagePlugin.ImageInfo.sectors != 560)
                return false;

            if(partitionStart > 0 || imagePlugin.ImageInfo.sectorSize != 256)
                return false;

            int spt = 0;
            if(imagePlugin.ImageInfo.sectors == 455)
                spt = 13;
            else
                spt = 16;

            byte[] vtoc_b = imagePlugin.ReadSector((ulong)(17 * spt));
            vtoc = new VTOC();
            IntPtr vtocPtr = Marshal.AllocHGlobal(256);
            Marshal.Copy(vtoc_b, 0, vtocPtr, 256);
            vtoc = (VTOC)Marshal.PtrToStructure(vtocPtr, typeof(VTOC));
            Marshal.FreeHGlobal(vtocPtr);

            return vtoc.catalogSector < spt && vtoc.maxTrackSectorPairsPerSector <= 122 && vtoc.sectorsPerTrack == spt && vtoc.bytesPerSector == 256;
        }

        public override void GetInformation(ImagePlugin imagePlugin, ulong partitionStart, ulong partitionEnd, out string information)
        {
            information = "";
            StringBuilder sb = new StringBuilder();

            int spt = 0;
            if(imagePlugin.ImageInfo.sectors == 455)
                spt = 13;
            else
                spt = 16;

            byte[] vtoc_b = imagePlugin.ReadSector((ulong)(17 * spt));
            vtoc = new VTOC();
            IntPtr vtocPtr = Marshal.AllocHGlobal(256);
            Marshal.Copy(vtoc_b, 0, vtocPtr, 256);
            vtoc = (VTOC)Marshal.PtrToStructure(vtocPtr, typeof(VTOC));
            Marshal.FreeHGlobal(vtocPtr);

            sb.AppendLine("Apple DOS File System");
            sb.AppendLine();
            sb.AppendFormat("Catalog starts at sector {0} of track {1}", vtoc.catalogSector, vtoc.catalogTrack).AppendLine();
            sb.AppendFormat("File system initialized by DOS release {0}", vtoc.dosRelease).AppendLine();
            sb.AppendFormat("Disk volume number {0}", vtoc.volumeNumber).AppendLine();
            sb.AppendFormat("Sectors allocated at most in track {0}", vtoc.lastAllocatedSector).AppendLine();
            sb.AppendFormat("{0} tracks in volume", vtoc.tracks).AppendLine();
            sb.AppendFormat("{0} sectors per track", vtoc.sectorsPerTrack).AppendLine();
            sb.AppendFormat("{0} bytes per sector", vtoc.bytesPerSector).AppendLine();
            sb.AppendFormat("Track allocation is {0}", vtoc.allocationDirection > 0 ? "forward" : "reverse").AppendLine();

            information = sb.ToString();

            xmlFSType = new Schemas.FileSystemType();
            xmlFSType.Bootable = true;
            xmlFSType.Clusters = (long)imagePlugin.ImageInfo.sectors;
            xmlFSType.ClusterSize = (int)imagePlugin.ImageInfo.sectorSize;
            xmlFSType.Type = "Apple DOS";

            return;
        }
    }
}