// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Compare.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : Verbs.
//
// --[ Description ] ----------------------------------------------------------
//
//     Implements the 'compare' verb.
//
// --[ License ] --------------------------------------------------------------
//
//     This program is free software: you can redistribute it and/or modify
//     it under the terms of the GNU General Public License as
//     published by the Free Software Foundation, either version 3 of the
//     License, or (at your option) any later version.
//
//     This program 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 General Public License for more details.
//
//     You should have received a copy of the GNU General Public License
//     along with this program.  If not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2019 Natalia Portillo
// ****************************************************************************/

using System;
using System.Collections.Generic;
using System.Text;
using DiscImageChef.CommonTypes;
using DiscImageChef.CommonTypes.Enums;
using DiscImageChef.CommonTypes.Interfaces;
using DiscImageChef.CommonTypes.Structs;
using DiscImageChef.Console;
using DiscImageChef.Core;
using Mono.Options;
using ImageInfo = DiscImageChef.CommonTypes.Structs.ImageInfo;

namespace DiscImageChef.Commands
{
    class CompareCommand : Command
    {
        string inputFile1;
        string inputFile2;
        bool   showHelp;

        public CompareCommand() : base("compare", "Compares two disc images.")
        {
            Options = new OptionSet
            {
                $"{MainClass.AssemblyTitle} {MainClass.AssemblyVersion?.InformationalVersion}",
                $"{MainClass.AssemblyCopyright}",
                "",
                $"usage: DiscImageChef {Name} imagefile1 imagefile2",
                "",
                Help,
                {"help|h|?", "Show this message and exit.", v => showHelp = v != null}
            };
        }

        public override int Invoke(IEnumerable<string> arguments)
        {
            List<string> extra = Options.Parse(arguments);

            if(showHelp)
            {
                Options.WriteOptionDescriptions(CommandSet.Out);
                return (int)ErrorNumber.HelpRequested;
            }

            MainClass.PrintCopyright();
            if(MainClass.Debug) DicConsole.DebugWriteLineEvent     += System.Console.Error.WriteLine;
            if(MainClass.Verbose) DicConsole.VerboseWriteLineEvent += System.Console.WriteLine;
            Statistics.AddCommand("compare");

            if(extra.Count > 2)
            {
                DicConsole.ErrorWriteLine("Too many arguments.");
                return (int)ErrorNumber.UnexpectedArgumentCount;
            }

            if(extra.Count <= 1)
            {
                DicConsole.ErrorWriteLine("Missing input image.");
                return (int)ErrorNumber.MissingArgument;
            }

            inputFile1 = extra[0];
            inputFile2 = extra[1];

            DicConsole.DebugWriteLine("Compare command", "--debug={0}",   MainClass.Debug);
            DicConsole.DebugWriteLine("Compare command", "--input1={0}",  inputFile1);
            DicConsole.DebugWriteLine("Compare command", "--input2={0}",  inputFile2);
            DicConsole.DebugWriteLine("Compare command", "--verbose={0}", MainClass.Verbose);

            FiltersList filtersList  = new FiltersList();
            IFilter     inputFilter1 = filtersList.GetFilter(inputFile1);
            filtersList = new FiltersList();
            IFilter inputFilter2 = filtersList.GetFilter(inputFile2);

            if(inputFilter1 == null)
            {
                DicConsole.ErrorWriteLine("Cannot open input file 1");
                return (int)ErrorNumber.CannotOpenFile;
            }

            if(inputFilter2 == null)
            {
                DicConsole.ErrorWriteLine("Cannot open input file 2");
                return (int)ErrorNumber.CannotOpenFile;
            }

            IMediaImage input1Format = ImageFormat.Detect(inputFilter1);
            IMediaImage input2Format = ImageFormat.Detect(inputFilter2);

            if(input1Format == null)
            {
                DicConsole.ErrorWriteLine("Input file 1 format not identified, not proceeding with comparison.");
                return (int)ErrorNumber.UnrecognizedFormat;
            }

            if(MainClass.Verbose)
                DicConsole.VerboseWriteLine("Input file 1 format identified by {0} ({1}).", input1Format.Name,
                                            input1Format.Id);
            else DicConsole.WriteLine("Input file 1 format identified by {0}.", input1Format.Name);

            if(input2Format == null)
            {
                DicConsole.ErrorWriteLine("Input file 2 format not identified, not proceeding with comparison.");
                return (int)ErrorNumber.UnrecognizedFormat;
            }

            if(MainClass.Verbose)
                DicConsole.VerboseWriteLine("Input file 2 format identified by {0} ({1}).", input2Format.Name,
                                            input2Format.Id);
            else DicConsole.WriteLine("Input file 2 format identified by {0}.", input2Format.Name);

            input1Format.Open(inputFilter1);
            input2Format.Open(inputFilter2);

            Statistics.AddMediaFormat(input1Format.Format);
            Statistics.AddMediaFormat(input2Format.Format);
            Statistics.AddMedia(input1Format.Info.MediaType, false);
            Statistics.AddMedia(input2Format.Info.MediaType, false);
            Statistics.AddFilter(inputFilter1.Name);
            Statistics.AddFilter(inputFilter2.Name);

            StringBuilder sb = new StringBuilder();

            if(MainClass.Verbose)
            {
                sb.AppendLine("\tDisc image 1\tDisc image 2");
                sb.AppendLine("================================");
                sb.AppendFormat("File\t{0}\t{1}", inputFile1, inputFile2).AppendLine();
                sb.AppendFormat("Disc image format\t{0}\t{1}", input1Format.Name, input2Format.Name).AppendLine();
            }
            else
            {
                sb.AppendFormat("Disc image 1: {0}", inputFile1).AppendLine();
                sb.AppendFormat("Disc image 2: {0}", inputFile2).AppendLine();
            }

            bool imagesDiffer = false;

            ImageInfo                        image1Info     = input1Format.Info;
            ImageInfo                        image2Info     = input2Format.Info;
            List<Session>                    image1Sessions = new List<Session>();
            List<Session>                    image2Sessions = new List<Session>();
            Dictionary<MediaTagType, byte[]> image1DiskTags = new Dictionary<MediaTagType, byte[]>();
            Dictionary<MediaTagType, byte[]> image2DiskTags = new Dictionary<MediaTagType, byte[]>();

            foreach(MediaTagType disktag in Enum.GetValues(typeof(MediaTagType)))
            {
                try
                {
                    byte[] temparray = input1Format.ReadDiskTag(disktag);
                    image1DiskTags.Add(disktag, temparray);
                }
                #pragma warning disable RECS0022 // A catch clause that catches System.Exception and has an empty body
                catch
                {
                    // ignored
                }
                #pragma warning restore RECS0022 // A catch clause that catches System.Exception and has an empty body
            }

            foreach(MediaTagType disktag in Enum.GetValues(typeof(MediaTagType)))
            {
                try
                {
                    byte[] temparray = input2Format.ReadDiskTag(disktag);
                    image2DiskTags.Add(disktag, temparray);
                }
                #pragma warning disable RECS0022 // A catch clause that catches System.Exception and has an empty body
                catch
                {
                    // ignored
                }
                #pragma warning restore RECS0022 // A catch clause that catches System.Exception and has an empty body
            }

            if(MainClass.Verbose)
            {
                sb.AppendFormat("Has partitions?\t{0}\t{1}", image1Info.HasPartitions, image2Info.HasPartitions)
                  .AppendLine();
                sb.AppendFormat("Has sessions?\t{0}\t{1}", image1Info.HasSessions, image2Info.HasSessions).AppendLine();
                sb.AppendFormat("Image size\t{0}\t{1}", image1Info.ImageSize, image2Info.ImageSize).AppendLine();
                sb.AppendFormat("Sectors\t{0}\t{1}", image1Info.Sectors, image2Info.Sectors).AppendLine();
                sb.AppendFormat("Sector size\t{0}\t{1}", image1Info.SectorSize, image2Info.SectorSize).AppendLine();
                sb.AppendFormat("Creation time\t{0}\t{1}", image1Info.CreationTime, image2Info.CreationTime)
                  .AppendLine();
                sb.AppendFormat("Last modification time\t{0}\t{1}", image1Info.LastModificationTime,
                                image2Info.LastModificationTime).AppendLine();
                sb.AppendFormat("Disk type\t{0}\t{1}", image1Info.MediaType, image2Info.MediaType).AppendLine();
                sb.AppendFormat("Image version\t{0}\t{1}", image1Info.Version, image2Info.Version).AppendLine();
                sb.AppendFormat("Image application\t{0}\t{1}", image1Info.Application, image2Info.Application)
                  .AppendLine();
                sb.AppendFormat("Image application version\t{0}\t{1}", image1Info.ApplicationVersion,
                                image2Info.ApplicationVersion).AppendLine();
                sb.AppendFormat("Image creator\t{0}\t{1}", image1Info.Creator, image2Info.Creator).AppendLine();
                sb.AppendFormat("Image name\t{0}\t{1}", image1Info.MediaTitle, image2Info.MediaTitle).AppendLine();
                sb.AppendFormat("Image comments\t{0}\t{1}", image1Info.Comments, image2Info.Comments).AppendLine();
                sb.AppendFormat("Disk manufacturer\t{0}\t{1}", image1Info.MediaManufacturer,
                                image2Info.MediaManufacturer).AppendLine();
                sb.AppendFormat("Disk model\t{0}\t{1}", image1Info.MediaModel, image2Info.MediaModel).AppendLine();
                sb.AppendFormat("Disk serial number\t{0}\t{1}", image1Info.MediaSerialNumber,
                                image2Info.MediaSerialNumber).AppendLine();
                sb.AppendFormat("Disk barcode\t{0}\t{1}", image1Info.MediaBarcode, image2Info.MediaBarcode)
                  .AppendLine();
                sb.AppendFormat("Disk part no.\t{0}\t{1}", image1Info.MediaPartNumber, image2Info.MediaPartNumber)
                  .AppendLine();
                sb.AppendFormat("Disk sequence\t{0}\t{1}", image1Info.MediaSequence, image2Info.MediaSequence)
                  .AppendLine();
                sb.AppendFormat("Last disk on sequence\t{0}\t{1}", image1Info.LastMediaSequence,
                                image2Info.LastMediaSequence).AppendLine();
                sb.AppendFormat("Drive manufacturer\t{0}\t{1}", image1Info.DriveManufacturer,
                                image2Info.DriveManufacturer).AppendLine();
                sb.AppendFormat("Drive firmware revision\t{0}\t{1}", image1Info.DriveFirmwareRevision,
                                image2Info.DriveFirmwareRevision).AppendLine();
                sb.AppendFormat("Drive model\t{0}\t{1}", image1Info.DriveModel, image2Info.DriveModel).AppendLine();
                sb.AppendFormat("Drive serial number\t{0}\t{1}", image1Info.DriveSerialNumber,
                                image2Info.DriveSerialNumber).AppendLine();
                foreach(MediaTagType disktag in Enum.GetValues(typeof(MediaTagType)))
                    sb.AppendFormat("Has {0}?\t{1}\t{2}", disktag, image1DiskTags.ContainsKey(disktag),
                                    image2DiskTags.ContainsKey(disktag)).AppendLine();
            }

            DicConsole.WriteLine("Comparing disk image characteristics");

            if(image1Info.HasPartitions != image2Info.HasPartitions)
            {
                imagesDiffer = true;
                if(!MainClass.Verbose) sb.AppendLine("Image partitioned status differ");
            }

            if(image1Info.HasSessions != image2Info.HasSessions)
            {
                imagesDiffer = true;
                if(!MainClass.Verbose) sb.AppendLine("Image session status differ");
            }

            if(image1Info.Sectors != image2Info.Sectors)
            {
                imagesDiffer = true;
                if(!MainClass.Verbose) sb.AppendLine("Image sectors differ");
            }

            if(image1Info.SectorSize != image2Info.SectorSize)
            {
                imagesDiffer = true;
                if(!MainClass.Verbose) sb.AppendLine("Image sector size differ");
            }

            if(image1Info.MediaType != image2Info.MediaType)
            {
                imagesDiffer = true;
                if(!MainClass.Verbose) sb.AppendLine("Disk type differ");
            }

            ulong leastSectors;
            if(image1Info.Sectors < image2Info.Sectors)
            {
                imagesDiffer = true;
                leastSectors = image1Info.Sectors;
                if(!MainClass.Verbose) sb.AppendLine("Image 2 has more sectors");
            }
            else if(image1Info.Sectors > image2Info.Sectors)
            {
                imagesDiffer = true;
                leastSectors = image2Info.Sectors;
                if(!MainClass.Verbose) sb.AppendLine("Image 1 has more sectors");
            }
            else leastSectors = image1Info.Sectors;

            DicConsole.WriteLine("Comparing sectors...");

            for(ulong sector = 0; sector < leastSectors; sector++)
            {
                DicConsole.Write("\rComparing sector {0} of {1}...", sector + 1, leastSectors);
                try
                {
                    byte[] image1Sector = input1Format.ReadSector(sector);
                    byte[] image2Sector = input2Format.ReadSector(sector);
                    ArrayHelpers.CompareBytes(out bool different, out bool sameSize, image1Sector, image2Sector);
                    if(different)
                    {
                        imagesDiffer = true;
                        sb.AppendFormat("Sector {0} is different", sector).AppendLine();
                    }
                    else if(!sameSize)
                    {
                        imagesDiffer = true;
                        sb
                           .AppendFormat("Sector {0} has different sizes ({1} bytes in image 1, {2} in image 2) but are otherwise identical",
                                         sector, image1Sector.LongLength, image2Sector.LongLength).AppendLine();
                    }
                }
                #pragma warning disable RECS0022 // A catch clause that catches System.Exception and has an empty body
                catch
                {
                    // ignored
                }
                #pragma warning restore RECS0022 // A catch clause that catches System.Exception and has an empty body
            }

            DicConsole.WriteLine();

            sb.AppendLine(imagesDiffer ? "Images differ" : "Images do not differ");

            DicConsole.WriteLine(sb.ToString());

            return (int)ErrorNumber.NoError;
        }
    }
}