// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : QNX4.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Component
//
// --[ Description ] ----------------------------------------------------------
//
//     Identifies the QNX4 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.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using DiscImageChef.CommonTypes;

namespace DiscImageChef.Filesystems
{
    public class QNX4 : Filesystem
    {
        struct QNX4_Extent
        {
            public uint block;
            public uint length;
        }

        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        struct QNX4_Inode
        {
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 16)]
            public byte[] di_fname;
            public uint di_size;
            public QNX4_Extent di_first_xtnt;
            public uint di_xblk;
            public uint di_ftime;
            public uint di_mtime;
            public uint di_atime;
            public uint di_ctime;
            public ushort di_num_xtnts;
            public ushort di_mode;
            public ushort di_uid;
            public ushort di_gid;
            public ushort di_nlink;
            public uint di_zero;
            public byte di_type;
            public byte di_status;
        }

        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        struct QNX4_LinkInfo
        {
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 48)]
            public byte[] dl_fname;
            public uint dl_inode_blk;
            public byte dl_inode_ndx;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 10)]
            public byte[] dl_spare;
            public byte dl_status;
        }

        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        struct QNX4_ExtentBlock
        {
            public uint next_xblk;
            public uint prev_xblk;
            public byte num_xtnts;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 3)]
            public byte[] spare;
            public uint num_blocks;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 60)]
            public QNX4_Extent[] xtnts;
            [MarshalAs(UnmanagedType.ByValArray, SizeConst = 8)]
            public byte[] signature;
            public QNX4_Extent first_xtnt;
        }

        [StructLayout(LayoutKind.Sequential, Pack = 1)]
        struct QNX4_Superblock
        {
            public QNX4_Inode rootDir;
            public QNX4_Inode inode;
            public QNX4_Inode boot;
            public QNX4_Inode altBoot;
        }

        readonly byte[] QNX4_RootDir_Fname = { 0x2F, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };

        public QNX4()
        {
            Name = "QNX4 Plugin";
            PluginUUID = new Guid("E73A63FA-B5B0-48BF-BF82-DA5F0A8170D2");
            CurrentEncoding = Encoding.GetEncoding("iso-8859-15");
        }

        public QNX4(ImagePlugins.ImagePlugin imagePlugin, Partition partition, Encoding encoding)
        {
            Name = "QNX4 Plugin";
            PluginUUID = new Guid("E73A63FA-B5B0-48BF-BF82-DA5F0A8170D2");
            if(encoding == null)
                CurrentEncoding = Encoding.GetEncoding("iso-8859-15");
            else
                CurrentEncoding = encoding;
        }

        public override bool Identify(ImagePlugins.ImagePlugin imagePlugin, Partition partition)
        {
            byte[] sector = imagePlugin.ReadSector(partition.Start + 1);
            if(sector.Length < 512)
                return false;

            QNX4_Superblock qnxSb = new QNX4_Superblock();
            IntPtr sbPtr = Marshal.AllocHGlobal(512);
            Marshal.Copy(sector, 0, sbPtr, 512);
            qnxSb = (QNX4_Superblock)Marshal.PtrToStructure(sbPtr, typeof(QNX4_Superblock));
            Marshal.FreeHGlobal(sbPtr);

            // Check root directory name
            if(!QNX4_RootDir_Fname.SequenceEqual(qnxSb.rootDir.di_fname))
                return false;

            // Check sizes are multiple of blocks
            if(qnxSb.rootDir.di_size % 512 != 0 ||
               qnxSb.inode.di_size % 512 != 0 ||
               qnxSb.boot.di_size % 512 != 0 ||
               qnxSb.altBoot.di_size % 512 != 0)
                return false;

            // Check extents are not past device
            if(qnxSb.rootDir.di_first_xtnt.block + partition.Start >= partition.End ||
               qnxSb.inode.di_first_xtnt.block + partition.Start >= partition.End ||
               qnxSb.boot.di_first_xtnt.block + partition.Start >= partition.End ||
               qnxSb.altBoot.di_first_xtnt.block + partition.Start >= partition.End)
                return false;

            // Check inodes are in use
            if((qnxSb.rootDir.di_status & 0x01) != 0x01 ||
               (qnxSb.inode.di_status & 0x01) != 0x01 ||
               (qnxSb.boot.di_status & 0x01) != 0x01)
                return false;

            // All hail filesystems without identification marks
            return true;
        }

        public override void GetInformation(ImagePlugins.ImagePlugin imagePlugin, Partition partition, out string information)
        {
            information = "";
            byte[] sector = imagePlugin.ReadSector(partition.Start + 1);
            if(sector.Length < 512)
                return;

            QNX4_Superblock qnxSb = new QNX4_Superblock();
            IntPtr sbPtr = Marshal.AllocHGlobal(512);
            Marshal.Copy(sector, 0, sbPtr, 512);
            qnxSb = (QNX4_Superblock)Marshal.PtrToStructure(sbPtr, typeof(QNX4_Superblock));
            Marshal.FreeHGlobal(sbPtr);

            // Too much useless information
            /*
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_fname = {0}", CurrentEncoding.GetString(qnxSb.rootDir.di_fname));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_size = {0}", qnxSb.rootDir.di_size);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_first_xtnt.block = {0}", qnxSb.rootDir.di_first_xtnt.block);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_first_xtnt.length = {0}", qnxSb.rootDir.di_first_xtnt.length);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_xblk = {0}", qnxSb.rootDir.di_xblk);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_ftime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_ftime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_mtime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_mtime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_atime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_atime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_ctime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_ctime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_num_xtnts = {0}", qnxSb.rootDir.di_num_xtnts);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_mode = {0}", Convert.ToString(qnxSb.rootDir.di_mode, 8));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_uid = {0}", qnxSb.rootDir.di_uid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_gid = {0}", qnxSb.rootDir.di_gid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_nlink = {0}", qnxSb.rootDir.di_nlink);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_zero = {0}", qnxSb.rootDir.di_zero);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_type = {0}", qnxSb.rootDir.di_type);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.rootDir.di_status = {0}", qnxSb.rootDir.di_status);

            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_fname = {0}", CurrentEncoding.GetString(qnxSb.inode.di_fname));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_size = {0}", qnxSb.inode.di_size);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_first_xtnt.block = {0}", qnxSb.inode.di_first_xtnt.block);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_first_xtnt.length = {0}", qnxSb.inode.di_first_xtnt.length);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_xblk = {0}", qnxSb.inode.di_xblk);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_ftime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.inode.di_ftime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_mtime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.inode.di_mtime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_atime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.inode.di_atime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_ctime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.inode.di_ctime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_num_xtnts = {0}", qnxSb.inode.di_num_xtnts);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_mode = {0}", Convert.ToString(qnxSb.inode.di_mode, 8));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_uid = {0}", qnxSb.inode.di_uid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_gid = {0}", qnxSb.inode.di_gid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_nlink = {0}", qnxSb.inode.di_nlink);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_zero = {0}", qnxSb.inode.di_zero);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_type = {0}", qnxSb.inode.di_type);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.inode.di_status = {0}", qnxSb.inode.di_status);

            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_fname = {0}", CurrentEncoding.GetString(qnxSb.boot.di_fname));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_size = {0}", qnxSb.boot.di_size);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_first_xtnt.block = {0}", qnxSb.boot.di_first_xtnt.block);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_first_xtnt.length = {0}", qnxSb.boot.di_first_xtnt.length);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_xblk = {0}", qnxSb.boot.di_xblk);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_ftime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.boot.di_ftime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_mtime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.boot.di_mtime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_atime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.boot.di_atime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_ctime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.boot.di_ctime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_num_xtnts = {0}", qnxSb.boot.di_num_xtnts);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_mode = {0}", Convert.ToString(qnxSb.boot.di_mode, 8));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_uid = {0}", qnxSb.boot.di_uid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_gid = {0}", qnxSb.boot.di_gid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_nlink = {0}", qnxSb.boot.di_nlink);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_zero = {0}", qnxSb.boot.di_zero);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_type = {0}", qnxSb.boot.di_type);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.boot.di_status = {0}", qnxSb.boot.di_status);

            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_fname = {0}", CurrentEncoding.GetString(qnxSb.altBoot.di_fname));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_size = {0}", qnxSb.altBoot.di_size);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_first_xtnt.block = {0}", qnxSb.altBoot.di_first_xtnt.block);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_first_xtnt.length = {0}", qnxSb.altBoot.di_first_xtnt.length);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_xblk = {0}", qnxSb.altBoot.di_xblk);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_ftime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.altBoot.di_ftime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_mtime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.altBoot.di_mtime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_atime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.altBoot.di_atime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_ctime = {0}", DateHandlers.UNIXUnsignedToDateTime(qnxSb.altBoot.di_ctime));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_num_xtnts = {0}", qnxSb.altBoot.di_num_xtnts);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_mode = {0}", Convert.ToString(qnxSb.altBoot.di_mode, 8));
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_uid = {0}", qnxSb.altBoot.di_uid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_gid = {0}", qnxSb.altBoot.di_gid);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_nlink = {0}", qnxSb.altBoot.di_nlink);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_zero = {0}", qnxSb.altBoot.di_zero);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_type = {0}", qnxSb.altBoot.di_type);
            DicConsole.DebugWriteLine("QNX4 plugin", "qnxSb.altBoot.di_status = {0}", qnxSb.altBoot.di_status);
            */

            information = string.Format("QNX4 filesystem\nCreated on {0}\n", DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_ftime));

            xmlFSType = new Schemas.FileSystemType
            {
                Type = "QNX4 filesystem",
                Clusters = (long)partition.Length,
                ClusterSize = 512,
                CreationDate = DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_ftime),
                CreationDateSpecified = true,
                ModificationDate = DateHandlers.UNIXUnsignedToDateTime(qnxSb.rootDir.di_mtime),
                ModificationDateSpecified = true
            };
            xmlFSType.Bootable |= (qnxSb.boot.di_size != 0 || qnxSb.altBoot.di_size != 0);
        }

        public override Errno Mount()
        {
            return Errno.NotImplemented;
        }

        public override Errno Mount(bool debug)
        {
            return Errno.NotImplemented;
        }

        public override Errno Unmount()
        {
            return Errno.NotImplemented;
        }

        public override Errno MapBlock(string path, long fileBlock, ref long deviceBlock)
        {
            return Errno.NotImplemented;
        }

        public override Errno GetAttributes(string path, ref FileAttributes attributes)
        {
            return Errno.NotImplemented;
        }

        public override Errno ListXAttr(string path, ref List<string> xattrs)
        {
            return Errno.NotImplemented;
        }

        public override Errno GetXattr(string path, string xattr, ref byte[] buf)
        {
            return Errno.NotImplemented;
        }

        public override Errno Read(string path, long offset, long size, ref byte[] buf)
        {
            return Errno.NotImplemented;
        }

        public override Errno ReadDir(string path, ref List<string> contents)
        {
            return Errno.NotImplemented;
        }

        public override Errno StatFs(ref FileSystemInfo stat)
        {
            return Errno.NotImplemented;
        }

        public override Errno Stat(string path, ref FileEntryInfo stat)
        {
            return Errno.NotImplemented;
        }

        public override Errno ReadLink(string path, ref string dest)
        {
            return Errno.NotImplemented;
        }
    }
}