/*
	Copyright (c) 2015 Ki

	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;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Threading;

namespace ILSpy.BamlDecompiler.Baml {
	internal class BamlBinaryReader : BinaryReader {
		public BamlBinaryReader(Stream stream)
			: base(stream) {
		}

		public int ReadEncodedInt() => Read7BitEncodedInt();
	}

	internal class BamlReader {
		const string MSBAML_SIG = "MSBAML";

		internal static bool IsBamlHeader(Stream str) {
			var pos = str.Position;
			try {
				var rdr = new BinaryReader(str, Encoding.Unicode);
				int len = (int)(rdr.ReadUInt32() >> 1);
				if (len != MSBAML_SIG.Length)
					return false;
				var sig = new string(rdr.ReadChars(len));
				return sig == MSBAML_SIG;
			}
			finally {
				str.Position = pos;
			}
		}

		static string ReadSignature(Stream str) {
			var rdr = new BinaryReader(str, Encoding.Unicode);
			uint len = rdr.ReadUInt32();
			var sig = new string(rdr.ReadChars((int)(len >> 1)));
			rdr.ReadBytes((int)(((len + 3) & ~3) - len));
			return sig;
		}

		public static BamlDocument ReadDocument(Stream str, CancellationToken token) {
			var ret = new BamlDocument();
			var reader = new BamlBinaryReader(str);
			ret.Signature = ReadSignature(str);
			if (ret.Signature != MSBAML_SIG) throw new NotSupportedException();
			ret.ReaderVersion = new BamlDocument.BamlVersion { Major = reader.ReadUInt16(), Minor = reader.ReadUInt16() };
			ret.UpdaterVersion = new BamlDocument.BamlVersion { Major = reader.ReadUInt16(), Minor = reader.ReadUInt16() };
			ret.WriterVersion = new BamlDocument.BamlVersion { Major = reader.ReadUInt16(), Minor = reader.ReadUInt16() };
			if (ret.ReaderVersion.Major != 0 || ret.ReaderVersion.Minor != 0x60 ||
			    ret.UpdaterVersion.Major != 0 || ret.UpdaterVersion.Minor != 0x60 ||
			    ret.WriterVersion.Major != 0 || ret.WriterVersion.Minor != 0x60)
				throw new NotSupportedException();

			var recs = new Dictionary<long, BamlRecord>();
			while (str.Position < str.Length) {
				token.ThrowIfCancellationRequested();

				long pos = str.Position;
				var type = (BamlRecordType)reader.ReadByte();
				BamlRecord rec = null;
				switch (type) {
					case BamlRecordType.AssemblyInfo:
						rec = new AssemblyInfoRecord();
						break;
					case BamlRecordType.AttributeInfo:
						rec = new AttributeInfoRecord();
						break;
					case BamlRecordType.ConstructorParametersStart:
						rec = new ConstructorParametersStartRecord();
						break;
					case BamlRecordType.ConstructorParametersEnd:
						rec = new ConstructorParametersEndRecord();
						break;
					case BamlRecordType.ConstructorParameterType:
						rec = new ConstructorParameterTypeRecord();
						break;
					case BamlRecordType.ConnectionId:
						rec = new ConnectionIdRecord();
						break;
					case BamlRecordType.ContentProperty:
						rec = new ContentPropertyRecord();
						break;
					case BamlRecordType.DefAttribute:
						rec = new DefAttributeRecord();
						break;
					case BamlRecordType.DefAttributeKeyString:
						rec = new DefAttributeKeyStringRecord();
						break;
					case BamlRecordType.DefAttributeKeyType:
						rec = new DefAttributeKeyTypeRecord();
						break;
					case BamlRecordType.DeferableContentStart:
						rec = new DeferableContentStartRecord();
						break;
					case BamlRecordType.DocumentEnd:
						rec = new DocumentEndRecord();
						break;
					case BamlRecordType.DocumentStart:
						rec = new DocumentStartRecord();
						break;
					case BamlRecordType.ElementEnd:
						rec = new ElementEndRecord();
						break;
					case BamlRecordType.ElementStart:
						rec = new ElementStartRecord();
						break;
					case BamlRecordType.KeyElementEnd:
						rec = new KeyElementEndRecord();
						break;
					case BamlRecordType.KeyElementStart:
						rec = new KeyElementStartRecord();
						break;
					case BamlRecordType.LineNumberAndPosition:
						rec = new LineNumberAndPositionRecord();
						break;
					case BamlRecordType.LinePosition:
						rec = new LinePositionRecord();
						break;
					case BamlRecordType.LiteralContent:
						rec = new LiteralContentRecord();
						break;
					case BamlRecordType.NamedElementStart:
						rec = new NamedElementStartRecord();
						break;
					case BamlRecordType.OptimizedStaticResource:
						rec = new OptimizedStaticResourceRecord();
						break;
					case BamlRecordType.PIMapping:
						rec = new PIMappingRecord();
						break;
					case BamlRecordType.PresentationOptionsAttribute:
						rec = new PresentationOptionsAttributeRecord();
						break;
					case BamlRecordType.Property:
						rec = new PropertyRecord();
						break;
					case BamlRecordType.PropertyArrayEnd:
						rec = new PropertyArrayEndRecord();
						break;
					case BamlRecordType.PropertyArrayStart:
						rec = new PropertyArrayStartRecord();
						break;
					case BamlRecordType.PropertyComplexEnd:
						rec = new PropertyComplexEndRecord();
						break;
					case BamlRecordType.PropertyComplexStart:
						rec = new PropertyComplexStartRecord();
						break;
					case BamlRecordType.PropertyCustom:
						rec = new PropertyCustomRecord();
						break;
					case BamlRecordType.PropertyDictionaryEnd:
						rec = new PropertyDictionaryEndRecord();
						break;
					case BamlRecordType.PropertyDictionaryStart:
						rec = new PropertyDictionaryStartRecord();
						break;
					case BamlRecordType.PropertyListEnd:
						rec = new PropertyListEndRecord();
						break;
					case BamlRecordType.PropertyListStart:
						rec = new PropertyListStartRecord();
						break;
					case BamlRecordType.PropertyStringReference:
						rec = new PropertyStringReferenceRecord();
						break;
					case BamlRecordType.PropertyTypeReference:
						rec = new PropertyTypeReferenceRecord();
						break;
					case BamlRecordType.PropertyWithConverter:
						rec = new PropertyWithConverterRecord();
						break;
					case BamlRecordType.PropertyWithExtension:
						rec = new PropertyWithExtensionRecord();
						break;
					case BamlRecordType.PropertyWithStaticResourceId:
						rec = new PropertyWithStaticResourceIdRecord();
						break;
					case BamlRecordType.RoutedEvent:
						rec = new RoutedEventRecord();
						break;
					case BamlRecordType.StaticResourceEnd:
						rec = new StaticResourceEndRecord();
						break;
					case BamlRecordType.StaticResourceId:
						rec = new StaticResourceIdRecord();
						break;
					case BamlRecordType.StaticResourceStart:
						rec = new StaticResourceStartRecord();
						break;
					case BamlRecordType.StringInfo:
						rec = new StringInfoRecord();
						break;
					case BamlRecordType.Text:
						rec = new TextRecord();
						break;
					case BamlRecordType.TextWithConverter:
						rec = new TextWithConverterRecord();
						break;
					case BamlRecordType.TextWithId:
						rec = new TextWithIdRecord();
						break;
					case BamlRecordType.TypeInfo:
						rec = new TypeInfoRecord();
						break;
					case BamlRecordType.TypeSerializerInfo:
						rec = new TypeSerializerInfoRecord();
						break;
					case BamlRecordType.XmlnsProperty:
						rec = new XmlnsPropertyRecord();
						break;
					case BamlRecordType.XmlAttribute:
					case BamlRecordType.ProcessingInstruction:
					case BamlRecordType.LastRecordType:
					case BamlRecordType.EndAttributes:
					case BamlRecordType.DefTag:
					case BamlRecordType.ClrEvent:
					case BamlRecordType.Comment:
					default:
						throw new NotSupportedException();
				}
				rec.Position = pos;

				rec.Read(reader);
				ret.Add(rec);
				recs.Add(pos, rec);
			}
			for (int i = 0; i < ret.Count; i++) {
				if (ret[i] is IBamlDeferRecord defer)
					defer.ReadDefer(ret, i, _ => recs[_]);
			}

			return ret;
		}
	}
}