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

#pragma warning disable 219

namespace BizHawk.MultiClient
{
	public static class MovieConvert
	{
		public static Movie ConvertFCM(string path, out string errorMsg)
		{
			errorMsg = "";

			try
			{
				Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);
				FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
				BinaryReader r = new BinaryReader(fs);

				byte[] signatureBytes = new byte[4];
				for (int x = 0; x < 4; x++)
					signatureBytes[x] = r.ReadByte();
				string signature = System.Text.Encoding.UTF8.GetString(signatureBytes);
				if (signature.Substring(0, 3) != "FCM")
				{
					errorMsg = "This is not a valid FCM file!";
					return null;
				}
					

				UInt32 version = r.ReadUInt32();
				m.Header.SetHeaderLine(MovieHeader.MovieVersion, "FCEU movie version " + version.ToString() + " (.fcm)");

				byte[] flags = new byte[4];
				for (int x = 0; x < 4; x++)
					flags[x] = r.ReadByte();

				UInt32 frameCount = r.ReadUInt32();

				m.SetRerecords((int)r.ReadUInt32());

				UInt32 movieDataSize = r.ReadUInt32();
				UInt32 savestateOffset = r.ReadUInt32();
				UInt32 firstFrameOffset = r.ReadUInt32();

				byte[] romCheckSum = r.ReadBytes(16);
				//TODO: ROM checksum movie header line (MD5)

				UInt32 EmuVersion = r.ReadUInt32();
				m.Header.SetHeaderLine(MovieHeader.EMULATIONVERSION, "FCEU " + EmuVersion.ToString());

				List<byte> romBytes = new List<byte>();
				while (true)
				{
					if (r.PeekChar() == 0)
						break;
					else
						romBytes.Add(r.ReadByte());
				}
				string rom = System.Text.Encoding.UTF8.GetString(romBytes.ToArray());
				m.Header.SetHeaderLine(MovieHeader.GAMENAME, rom);

				r.ReadByte(); //Advance past null byte

				List<byte> authorBytes = new List<byte>();
				while (true)
				{
					if (r.PeekChar() == 0)
						break;
					else
						authorBytes.Add(r.ReadByte());
				}
				string author = System.Text.Encoding.UTF8.GetString(authorBytes.ToArray());
				m.Header.SetHeaderLine(MovieHeader.AUTHOR, author);

				r.ReadByte(); //Advance past null byte

				bool movieSyncHackOn = true;
				if ((int)(flags[0] & 16) > 0)
					movieSyncHackOn = false;

				bool pal = false;
				if ((int)(flags[0] & 4) > 0)
					pal = true;

				m.Header.SetHeaderLine("SyncHack", movieSyncHackOn.ToString());
				m.Header.SetHeaderLine("PAL", pal.ToString());

				//Power on vs reset
				if ((int)(flags[0] & 8) > 0)
				{ } //Power-on = default
				else if ((int)(flags[0] & 2) > 0)
				{ } //we don't support start from reset, do some kind of notification here
				else
				{ } //this movie starts from savestate, freak out here

				//Advance to first byte of input data
				//byte[] throwaway = new byte[firstFrameOffset];
				//r.Read(throwaway, 0, (int)firstFrameOffset);
				r.BaseStream.Position = firstFrameOffset;
				//moviedatasize stuff

				//read frame data
				//TODO: special commands like fds disk switch, etc, and power/reset

				//TODO: use stringbuilder class for speed
				//string ButtonLookup = "RLDUSsBARLDUSsBARLDUSsBARLDUSsBA"; //TODO: This assumes input data is the same in fcm as bizhawk, which it isn't
				string frame = "|0|"; //TODO: read reset command rather than hard code it off
				for (int x = 0; x < frameCount; x++)
				{
					byte joy = r.ReadByte();

					//Read each byte of controller one data

					frame += "|";

					r.ReadBytes(3); //Lose remaining controllers for now
					m.AppendFrame(frame);
				}

				//set 4 score flag if necessary
				r.Close();
				return m;
			}
			catch
			{
				errorMsg = "Error opening file.";
				return null;
			}
		}

		public static Movie ConvertMMV(string path, out string errorMsg)
		{
			errorMsg = "";
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
			BinaryReader r = new BinaryReader(fs);

			byte[] signatureBytes = new byte[4];
			for (int x = 0; x < 4; x++)
				signatureBytes[x] = r.ReadByte();
			string signature = System.Text.Encoding.UTF8.GetString(signatureBytes);
			if (signature != "MMV\0")
			{
				errorMsg = "This is not a valid MMV file.";
				return null;
			}

			UInt32 version = r.ReadUInt32();
			m.Header.SetHeaderLine(MovieHeader.MOVIEVERSION, "Dega version " + version.ToString());

			UInt32 framecount = r.ReadUInt32();

			m.SetRerecords((int)r.ReadUInt32());

			UInt32 IsFromReset = r.ReadUInt32();
			if (IsFromReset == 0)
			{
				errorMsg = "Movies that begin with a savestate are not supported.";
				return null;
			}

			UInt32 stateOffset = r.ReadUInt32();
			UInt32 inputDataOffset = r.ReadUInt32();
			UInt32 inputPacketSize = r.ReadUInt32();

			byte[] authorBytes = new byte[64];
			for (int x = 0; x < 64; x++)
				authorBytes[x] = r.ReadByte();

			string author = System.Text.Encoding.UTF8.GetString(authorBytes);
			//TODO: remove null characters
			m.Header.SetHeaderLine(MovieHeader.AUTHOR, author);

			//4-byte little endian flags
			byte flags = r.ReadByte();

			bool pal;
			if ((int)(flags & 2) > 0)
				pal = true;
			else
				pal = false;
			m.Header.SetHeaderLine("PAL", pal.ToString());

			bool japan;
			if ((int)(flags & 4) > 0)
				japan = true;
			else
				japan = false;
			m.Header.SetHeaderLine("Japan", japan.ToString());

			bool gamegear;
			if ((int)(flags & 8) > 0)
			{
				gamegear = true;
				m.Header.SetHeaderLine(MovieHeader.PLATFORM, "GG");
			}
			else
			{
				gamegear = false;
				m.Header.SetHeaderLine(MovieHeader.PLATFORM, "SMS");
			}

			r.ReadBytes(3); //Unused flags

			byte[] romnameBytes = new byte[128];
			for (int x = 0; x < 128; x++)
				romnameBytes[x] = r.ReadByte();
			string romname = System.Text.Encoding.UTF8.GetString(romnameBytes.ToArray());
			//TODO: remove null characters
			m.Header.SetHeaderLine(MovieHeader.GAMENAME, romname);

			byte[] MD5Bytes = new byte[16];
			for (int x = 0; x < 16; x++)
				MD5Bytes[x] = r.ReadByte();
			string MD5 = System.Text.Encoding.UTF8.GetString(MD5Bytes.ToArray());
			//TODO: format correctly
			m.Header.SetHeaderLine("MD5", MD5);


			for (int x = 0; x < (framecount); x++)
			{
				//TODO: use StringBuilder

				string frame = "|";
				char start;
				byte tmp;

				tmp = r.ReadByte();
				if ((int)(tmp & 1) > 0) frame += "U"; else frame += ".";
				if ((int)(tmp & 2) > 0) frame += "D"; else frame += ".";
				if ((int)(tmp & 4) > 0) frame += "L"; else frame += ".";
				if ((int)(tmp & 8) > 0) frame += "R"; else frame += ".";
				if ((int)(tmp & 16) > 0) frame += "1"; else frame += ".";
				if ((int)(tmp & 32) > 0) frame += "2|"; else frame += ".|";

				if ((int)(tmp & 64) > 0 && (!gamegear)) start = 'P'; else start = '.';
				if ((int)(tmp & 128) > 0 && gamegear) start = 'P'; else start = '.';

				//Controller 2
				tmp = r.ReadByte();
				if ((int)(tmp & 1) > 0) frame += "U"; else frame += ".";
				if ((int)(tmp & 2) > 0) frame += "D"; else frame += ".";
				if ((int)(tmp & 4) > 0) frame += "L"; else frame += ".";
				if ((int)(tmp & 8) > 0) frame += "R"; else frame += ".";
				if ((int)(tmp & 16) > 0) frame += "1"; else frame += ".";
				if ((int)(tmp & 32) > 0) frame += "2|"; else frame += ".|";

				frame += start;
				frame += ".|";
				m.AppendFrame(frame);
			}
			m.WriteMovie();
			return m;
		}

		public static string ConvertMCM(string path)
		{
			string converted = Path.ChangeExtension(path, ".tas");

			return converted;
		}

		public static Movie ConvertSMV(string path, out string errorMSG)
		{
			errorMSG = "";
			FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
			BinaryReader r = new BinaryReader(fs);

			byte[] signatureBytes = new byte[4];
			for (int x = 0; x < 4; x++)
				signatureBytes[x] = r.ReadByte();
			string signature = System.Text.Encoding.UTF8.GetString(signatureBytes);
			if (signature.Substring(0, 3) != "SMV")
			{
				errorMSG = "This is not a valid SMV file.";
				return null;
			}

			UInt32 version = r.ReadUInt32();

			switch (version)
			{
				case 1:
					return ConvertSMV143(r, path);
				case 4:
					return ConvertSMV151(r, path);
				case 5:
					return ConvertSMV152(r, path);
				default:
				{
					errorMSG = "SMV version not recognized, 143, 151, and 152 are currently supported";
					return null; 
				}
			}
		}

		private static Movie ConvertSMV152(BinaryReader r, string path)
		{
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			UInt32 GUID = r.ReadUInt32();

			return m;
		}

		private static Movie ConvertSMV151(BinaryReader r, string path)
		{
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			return m;
		}

		private static Movie ConvertSMV143(BinaryReader r, string path)
		{
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			UInt32 GUID = r.ReadUInt32();
			m.Header.SetHeaderLine(MovieHeader.GUID, GUID.ToString()); //TODO: format to hex string
			m.SetRerecords((int)r.ReadUInt32());

			UInt32 framecount = r.ReadUInt32();
			byte ControllerFlags = r.ReadByte();

			int numControllers;
			if ((int)(ControllerFlags & 16) > 0)
				numControllers = 5;
			else if ((int)(ControllerFlags & 8) > 0)
				numControllers = 4;
			else if ((int)(ControllerFlags & 4) > 0)
				numControllers = 3;
			else if ((int)(ControllerFlags & 2) > 0)
				numControllers = 2;
			else
				numControllers = 1;


			byte MovieFlags = r.ReadByte();

			if ((int)(MovieFlags & 1) == 0)
				return null; //TODO: Savestate movies not supported error

			if ((int)(MovieFlags & 2) > 0)
			{
				m.Header.SetHeaderLine("PAL", "True");
			}

			byte SyncOptions = r.ReadByte();
			byte SyncOptions2 = r.ReadByte();
			//TODO: these

			UInt32 SavestateOffset = r.ReadUInt32();
			UInt32 FrameDataOffset = r.ReadUInt32();

			//TODO: get extra rom info

			r.BaseStream.Position = FrameDataOffset;
			for (int x = 0; x < framecount; x++)
			{
				//TODO: FF FF for all controllers = Reset
				//string frame = "|0|";
				for (int y = 0; y < numControllers; y++)
				{
					UInt16 fd = r.ReadUInt16();
				}


			}

			return m;
		}

		public static Movie ConvertGMV(string path, out string errorMsg)
		{
			errorMsg = "";
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			return m;
		}

		public static Movie ConvertVBM(string path, out string errorMsg)
		{
			errorMsg = "";
			//Converts vbm to native text based format.
			Movie m = new Movie(Path.ChangeExtension(path, ".tas"), MOVIEMODE.PLAY);

			FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
			BinaryReader r = new BinaryReader(fs);

			//0xoffset
			//0x00
			UInt32 signature = r.ReadUInt32();  //always 56 42 4D 1A  (VBM\x1A)
			if (signature != 0x56424D1A)
			{
				errorMsg = "This is not a valid VBM file.";
				return null;
			}

			UInt32 versionno = r.ReadUInt32();  //always 1
			UInt32 uid = r.ReadUInt32();		//time of recording
			m.Header.SetHeaderLine(MovieHeader.GUID, uid.ToString());
			UInt32 framecount = r.ReadUInt32();

			//0x10
			UInt32 rerecordcount = r.ReadUInt32();
			m.SetRerecords((int)rerecordcount);
			m.Header.SetHeaderLine(MovieHeader.RERECORDS, m.Rerecords.ToString());
			Byte moviestartflags = r.ReadByte();



			bool startfromquicksave = false;
			bool startfromsram = false;

			if ((moviestartflags & 0x01) > 0) startfromquicksave = true;
			if ((moviestartflags & 0x02) > 0) startfromsram = true;

			if (startfromquicksave & startfromsram)
			{
				errorMsg = "Movies that begin with a savestate are not supported.";
				return null;
			}

			//0x15
			Byte controllerflags = r.ReadByte();

			int numControllers;                   //number of controllers changes for SGB

			if ((controllerflags & 0x08) > 0) numControllers = 4;
			else if ((controllerflags & 0x04) > 0) numControllers = 3;
			else if ((controllerflags & 0x02) > 0) numControllers = 2;
			else numControllers = 1;

			//0x16
			Byte systemflags = r.ReadByte();    //what system is it?

			bool is_gba = false;
			bool is_gbc = false;
			bool is_sgb = false;
			bool is_gb = false;

			if ((systemflags & 0x04) > 0) is_sgb = true;
			if ((systemflags & 0x02) > 0) is_gbc = true;
			if ((systemflags & 0x01) > 0) is_gba = true;
			else is_gb = true;

			if (is_gb & is_gbc & is_gba & is_sgb)
			{
				errorMsg = "Not a valid VBM platform type.";
				return null;
			}
			//TODO: set platform in header

			//0x17
			Byte flags = r.ReadByte();  //emulation flags

			//placeholder for reserved bit (set to 0)
			bool echoramfix = false;
			bool gbchdma5fix = false;
			bool lagreduction = false;
			//placeholder for unsupported bit
			bool rtcenable = false;
			bool skipbiosfile = false;
			bool usebiosfile = false;

			if ((flags & 0x40) > 0) echoramfix = true;
			if ((flags & 0x20) > 0) gbchdma5fix = true;
			if ((flags & 0x10) > 0) lagreduction = true;
			if ((flags & 0x08) > 0) 
			{
				errorMsg = "Invalid VBM file";
				return null;
			}
			if ((flags & 0x04) > 0) rtcenable = true;
			if ((flags & 0x02) > 0) skipbiosfile = true;
			if ((flags & 0x01) > 0) usebiosfile = true;

			//0x18
			UInt32 winsavetype = r.ReadUInt32();
			UInt32 winflashsize = r.ReadUInt32();

			//0x20
			UInt32 gbemulatortype = r.ReadUInt32();

			char[] internalgamename = r.ReadChars(0x0C);
			string gamename = new String(internalgamename);
			m.Header.SetHeaderLine(MovieHeader.GAMENAME, gamename);

			//0x30
			Byte minorversion = r.ReadByte();
			Byte internalcrc = r.ReadByte();
			UInt16 internalchacksum = r.ReadUInt16();
			UInt32 unitcode = r.ReadUInt32();
			UInt32 saveoffset = r.ReadUInt32();		//set to 0 if unused
			UInt32 controllerdataoffset = r.ReadUInt32();

			//0x40  start info.
			char[] authorsname = r.ReadChars(0x40);		//vbm specification states these strings 
			string author = new String(authorsname);	//are locale dependant.
			m.Header.SetHeaderLine(MovieHeader.AUTHOR, author);

			//0x80
			char[] moviedescription = r.ReadChars(0x80);

			//0x0100
			//End of VBM header

			//if there is no SRAM or savestate, the controller data should start at 0x0100 by default,
			//but this is not buaranteed

			//TODO: implement start data. There are no specifics on the googlecode page as to how long
			//the SRAM or savestate should be.

			UInt32 framesleft = framecount;

			r.BaseStream.Position = controllerdataoffset;    //advances to controller data.

			int currentoffset = (int)controllerdataoffset;

			for (int i = 1; i <= framecount; i++)
			{
				UInt16 controllerstate = r.ReadUInt16();
				string frame = "|.|"; //TODO: reset goes here
				if ((controllerstate & 0x0010) > 0) frame += "R"; else frame += ".";
				if ((controllerstate & 0x0020) > 0) frame += "L"; else frame += ".";
				if ((controllerstate & 0x0080) > 0) frame += "D"; else frame += ".";
				if ((controllerstate & 0x0040) > 0) frame += "U"; else frame += ".";
				if ((controllerstate & 0x0008) > 0) frame += "S"; else frame += ".";
				if ((controllerstate & 0x0004) > 0) frame += "s"; else frame += ".";
				if ((controllerstate & 0x0002) > 0) frame += "B"; else frame += ".";
				if ((controllerstate & 0x0001) > 0) frame += "A"; else frame += ".";
				frame += "|";


				m.AppendFrame(frame);

			}

			m.WriteMovie();

			//format: |.|RLDUSsBA| according to "GetControllersAsMnemonic()"
			//note: this is GBC or less ONLY, not GBA (no L or R button)
			//we need to change this when we add reset or whatever.
			//VBM file format: http://code.google.com/p/vba-rerecording/wiki/VBM

			return m;
		}
	}
}