using System.Runtime.CompilerServices;
using System.Xml.Linq;

//File table parsing algorithm: https://github.com/mbystryantsev/consolgames-tools/blob/master/game-specific/Silent%20Hill/FilesExtractor/Silent.cpp

namespace LibCD {
    class App {
        static string CalledFileDir([CallerFilePath] string path = null) {
            return System.IO.Path.GetDirectoryName(path);
        }

        static string TestDataDir {
            get {
                return Path.Combine(CalledFileDir(), "..", "TestData");

            }
        }

        static string ImageFilePath {
            get { return Path.Combine(TestDataDir, "Image.bin"); }
        }


        static void PrintFileSystem(ISO9660.FileSystem.Directory dir, string fullPath) {
            fullPath += dir.Name;
            Console.WriteLine(fullPath);

            foreach (var file in dir.Files) {
                Console.WriteLine($"{fullPath}/{file.Name} | LBA: {file.LBA}  SIZE: {file.Size}");
            }

            foreach (var childDir in dir.Directories) {
                PrintFileSystem(childDir, fullPath + "/");
            }
        }


        public static ISO9660.FileSystem.File? FindFile(ISO9660.FileSystem fs, string name) {
            var dir = fs.RootDirectory;
            foreach (var file in dir.Files) {
                if (file.Name.StartsWith(name)) {
                    return file;
                }
            }
            return null;
        }


        struct ShFileRecord {
            public uint b1;
            public uint b2;
            public uint b3;

            public uint StartSector {
                get {
                    return b1 & 0x7ffff;
                }
            }
            public uint ChunkCount {
                get {
                    return b1 >> 19;
                }
            }

            public uint DirectoryIndex {
                get {
                    return b2 & 0xf;
                }
            }


            public uint Name0 {
                get {
                    return (b2 >> 4) & 0xffffff;
                }
            }
            public uint Dummy {
                get {
                    return (b2 >> 28);
                }
            }

            public uint Name1 {
                get {
                    return b3 & 0xffffff;
                }
            }

            public uint ExtensionIndex {
                get {
                    return b3 >> 24;
                }
            }


            public string Name {
                get {
                    string result = "";
                    uint[] values = new uint[] { Name0, Name1 };

                    for (int j = 0; j < 2; j++) {
                        uint v = values[j];
                        for (int i = 0; i < 4 && v != 0; i++) {
                            byte c = (byte)((v & 0x3F) + 0x20);
                            result += (char)c;
                            v >>= 6;
                        }
                    }
                    return result;
                }
            }

            public string Directory {
                get {
                    return DefaultDirectoryStruct[DirectoryIndex];
                }
            }

            public string Extension {
                get {
                    return DefaultExtensions[DirectoryIndex];
                }
            }

            public string Path {
                get {
                    return System.IO.Path.Combine(Directory, $"{Name}{Extension}");
                }
            }

            public uint Size {
                get {
                    return ChunkCount * 0x100;
                }
            }
        }

        static string[] DefaultExtensions = new string[16]
        {
            ".TIM", ".VAB", ".BIN", ".DMS",
            ".ANM", ".PLM", ".IPD", ".ILM",
            ".TMD", ".DAT", ".KDT", ".CMP",
            ".TXT", "",     "",     ""
        };

        static string[] DefaultDirectoryStruct = new string[16]
        {
            "1ST",    "ANIM",   "BG",     "CHARA",
            "ITEM",   "MISC",   "SND",    "TEST",
            "TIM",    "VIN",    "XA",     "",
            "",       "",       "",       ""
        };

        public static void Main() {
            Console.WriteLine(ImageFilePath);

            var fs = new ISO9660.FileSystem(File.OpenRead(ImageFilePath));
            var xaDiscLabel = fs.PrimaryVolumeDescriptor.GetXADiscLabel();

            var exeFile = FindFile(fs, "SLUS_007.07");
            var dataFile = FindFile(fs, "SILENT");

            var exeFileStream = exeFile.OpenRead(fs.SectorStream);
            exeFileStream.Seek(0xB91C, SeekOrigin.Current);

            List<ShFileRecord> fileRecords = new List<ShFileRecord>();
            for(int i = 0; i < 2074; ++i) {
                fileRecords.Add(LibCD.Serialization.StreamReader.ReadStruct<ShFileRecord>(exeFileStream));
            }

            string exportDirectory = @"E:\CdContent";
            foreach (var file in fileRecords) {
                fs.SectorStream.SeekToSector(file.StartSector);
                var srcFileStream = new CdByteStream(fs.SectorStream);
                byte[] data = srcFileStream.Read((int)file.Size);

                string outPath = Path.Combine(exportDirectory, file.Path);
                string outDir = Path.GetDirectoryName(outPath);
                Directory.CreateDirectory(outDir);

                File.WriteAllBytes(outPath, data);


                Console.WriteLine($"{file.Path}");
            }


            //
            Console.WriteLine("Done");
        }
    }
}