/* ScummVM - Scumm Interpreter
 * Copyright (C) 2001  Ludvig Strigeus
 * Copyright (C) 2001-2003 The ScummVM project
 *
 * 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 2
 * 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * $Header$
 *
 */

#include "stdafx.h"
#include "scumm.h"
#include "resource.h"
#include "bundle.h"
#include "verbs.h"
#include "scumm/sound.h"
#include "common/map.h"
#include "common/str.h"
#include "gui/message.h"
#include "dialogs.h"

uint16 newTag2Old(uint32 oldTag);

/* Open a room */
void Scumm::openRoom(int room) {
	int room_offs, roomlimit;
	bool result;
	char buf[128];
	char buf2[128] = "";

	debug(9, "openRoom(%d)", room);
	assert(room >= 0);

	/* Don't load the same room again */
	if (_lastLoadedRoom == room)
		return;
	_lastLoadedRoom = room;

	/* Room -1 means close file */
	if (room == -1) {
		_encbyte = 0;
		deleteRoomOffsets();
		_fileHandle.close();
		return;
	}

	/* Either xxx.lfl or monkey.xxx file name */
	while (1) {
		if (_features & GF_SMALL_NAMES)
			roomlimit = 98;
		else
			roomlimit = 900;
		if (_features & GF_EXTERNAL_CHARSET && room >= roomlimit)
			room_offs = 0;
		else
			room_offs = room ? _roomFileOffsets[room] : 0;

		if (room_offs == -1)
			break;

		if (room_offs != 0 && room != 0) {
			_fileOffset = _roomFileOffsets[room];
			return;
		}
		if (!(_features & GF_SMALL_HEADER)) {

			if (_features & GF_AFTER_V7) {
				if (room > 0 && (_features & GF_AFTER_V8))
					VAR(VAR_CURRENTDISK) = res.roomno[rtRoom][room];
				sprintf(buf, "%s.la%d", _exe_name, room == 0 ? 0 : res.roomno[rtRoom][room]);
				sprintf(buf2, "%s.%.3d", _exe_name, room == 0 ? 0 : res.roomno[rtRoom][room]);
			} else if (_features & GF_AFTER_HEV7) {
				sprintf(buf, "%s.he%.1d", _exe_name, room == 0 ? 0 : 1);
			} else if (_features & GF_HUMONGOUS)
				sprintf(buf, "%s.he%.1d", _exe_name, room == 0 ? 0 : res.roomno[rtRoom][room]);
			else {
				sprintf(buf, "%s.%.3d",  _exe_name, room == 0 ? 0 : res.roomno[rtRoom][room]);
				if (_gameId == GID_SAMNMAX)
					sprintf(buf2, "%s.sm%.1d",  _exe_name, room == 0 ? 0 : res.roomno[rtRoom][room]);
			}

			_encbyte = (_features & GF_USE_KEY) ? 0x69 : 0;
		} else if (!(_features & GF_SMALL_NAMES)) {
			if (room == 0 || room >= 900) {
				sprintf(buf, "%.3d.lfl", room);
				_encbyte = 0;
				if (openResourceFile(buf)) {
					return;
				}
				askForDisk(buf, room == 0 ? 0 : res.roomno[rtRoom][room]);

			} else {
				sprintf(buf, "disk%.2d.lec", room == 0 ? 0 : res.roomno[rtRoom][room]);
				_encbyte = 0x69;
			}
		} else {
			sprintf(buf, "%.2d.lfl", room);
			_encbyte = (_features & GF_USE_KEY) ? 0xFF : 0;
		}

		result = openResourceFile(buf);
		if ((result == false) && (buf2[0]))
			result = openResourceFile(buf2);
			
		if (result) {
			if (room == 0)
				return;
			if (_features & GF_EXTERNAL_CHARSET && room >= roomlimit)
				return;
			readRoomsOffsets();
			_fileOffset = _roomFileOffsets[room];

			if (_fileOffset != 8)
				return;

			error("Room %d not in %s", room, buf);
			return;
		}
		askForDisk(buf, room == 0 ? 0 : res.roomno[rtRoom][room]);
	}

	do {
		sprintf(buf, "%.3d.lfl", room);
		_encbyte = 0;
		if (openResourceFile(buf))
			break;
		askForDisk(buf, room == 0 ? 0 : res.roomno[rtRoom][room]);
	} while (1);

	deleteRoomOffsets();
	_fileOffset = 0;		// start of file
}

void Scumm::closeRoom() {
	if (_lastLoadedRoom != -1) {
		_lastLoadedRoom = -1;
		_encbyte = 0;
		deleteRoomOffsets();
		_fileHandle.close();
	}
}

/* Delete the currently loaded room offsets */
void Scumm::deleteRoomOffsets() {
	if (!(_features & GF_SMALL_HEADER) && !_dynamicRoomOffsets)
		return;

	for (int i = 0; i < _maxRooms; i++) {
		if (_roomFileOffsets[i] != 0xFFFFFFFF)
			_roomFileOffsets[i] = 0;
	}
}

/* Read room offsets */
void Scumm::readRoomsOffsets() {
	int num, room, i;
	byte *ptr;

	debug(9, "readRoomOffsets()");

	deleteRoomOffsets();
	if (_features & GF_SMALL_NAMES)
		return;

	if (_features & GF_AFTER_HEV7) {
		num = READ_LE_UINT16(_HEV7RoomOffsets);
		ptr = _HEV7RoomOffsets + 2;
		for (i = 0; i < num; i++) {
			_roomFileOffsets[i] = READ_LE_UINT32(ptr);	
			ptr += 4;
		}
		return;
	}
	
	if (!(_features & GF_SMALL_HEADER)) {
		if (!_dynamicRoomOffsets)
			return;

		_fileHandle.seek(16, SEEK_SET);
	} else {
		_fileHandle.seek(12, SEEK_SET);	// Directly searching for the room offset block would be more generic...
	}

	num = _fileHandle.readByte();
	while (num--) {
		room = _fileHandle.readByte();
		if (_roomFileOffsets[room] != 0xFFFFFFFF) {
			_roomFileOffsets[room] = _fileHandle.readUint32LE();
		} else {
			_fileHandle.readUint32LE();
		}
	}
}

bool Scumm::openResourceFile(const char *filename) {
	char buf[256];

	debug(9, "openResourceFile(%s)", filename);

	if (_fileHandle.isOpen() == true) {
		_fileHandle.close();
	}

	strcpy(buf, filename);
	_fileHandle.open(buf, getGameDataPath(), 1, _encbyte);

	return _fileHandle.isOpen();
}

void Scumm::askForDisk(const char *filename, int disknum) {
	char buf[128];

	if (_features & GF_AFTER_V8) {
		char result;

		_bundle->closeVoiceFile();
		_bundle->closeMusicFile();

		sprintf(buf, "Cannot find file: '%s'\nInsert disc %d into drive %s\nHit Ok to retry, Cancel to exit", filename, disknum, getGameDataPath());

		result = displayError(true, buf);
		if (result == 2)
			error("Cannot find file: '%s'", filename);
	} else { 
		sprintf(buf, "Cannot find file: '%s'", filename);
		InfoDialog* dialog = new InfoDialog(_newgui, this, (char*)buf);
		runDialog (dialog);
		delete dialog;
		error("Cannot find file: '%s'", filename);
	}
}

void Scumm::readIndexFile() {
	uint32 blocktype, itemsize;
	int numblock = 0;
	int num, i;
	bool stop = false;

	debug(9, "readIndexFile()");

	closeRoom();
	openRoom(0);

	if (!(_features & GF_AFTER_V6)) {
		/* Figure out the sizes of various resources */
		while (!_fileHandle.eof()) {
			blocktype = fileReadDword();
			itemsize = _fileHandle.readUint32BE();
			if (_fileHandle.ioFailed())
				break;
			switch (blocktype) {
			case MKID('DOBJ'):
				_numGlobalObjects = _fileHandle.readUint16LE();
				itemsize -= 2;
				break;
			case MKID('DROO'):
				_numRooms = _fileHandle.readUint16LE();
				itemsize -= 2;
				break;

			case MKID('DSCR'):
				_numScripts = _fileHandle.readUint16LE();
				itemsize -= 2;
				break;

			case MKID('DCOS'):
				_numCostumes = _fileHandle.readUint16LE();
				itemsize -= 2;
				break;

			case MKID('DSOU'):
				_numSounds = _fileHandle.readUint16LE();
				itemsize -= 2;
				break;
			}
			_fileHandle.seek(itemsize - 8, SEEK_CUR);
		}
		_fileHandle.clearIOFailed();
		_fileHandle.seek(0, SEEK_SET);
	}

	while (!stop) {
		blocktype = fileReadDword();

		if (_fileHandle.ioFailed())
			break;
		itemsize = _fileHandle.readUint32BE();

		numblock++;

		switch (blocktype) {
		case MKID('DCHR'):
		case MKID('DIRF'):
			readResTypeList(rtCharset, MKID('CHAR'), "charset");
			break;
		
		case MKID('DOBJ'):
			if (_features & GF_AFTER_V8)
				num = _fileHandle.readUint32LE();
			else
				num = _fileHandle.readUint16LE();
			assert(num == _numGlobalObjects);
			

			if (_features & GF_AFTER_V8) {	/* FIXME: Not sure.. */
				char buffer[40];
				for (i = 0; i < num; i++) {
					_fileHandle.read(buffer, 40);
					if (buffer[0]) {
						// Add to object name-to-id map
						_objectIDMap[buffer] = i;
					}
					_objectStateTable[i] = _fileHandle.readByte();
					_objectRoomTable[i] = _fileHandle.readByte();
					_classData[i] = _fileHandle.readUint32LE();
				}
				memset(_objectOwnerTable, 0xFF, num);
			} else if (_features & GF_AFTER_V7) {
				_fileHandle.read(_objectStateTable, num);
				_fileHandle.read(_objectRoomTable, num);
				memset(_objectOwnerTable, 0xFF, num);
			} else {
				_fileHandle.read(_objectOwnerTable, num);
				for (i = 0; i < num; i++) {
					_objectStateTable[i] = _objectOwnerTable[i] >> OF_STATE_SHL;
					_objectOwnerTable[i] &= OF_OWNER_MASK;
				}
				if (_features & GF_AFTER_HEV7) {
					// FIXME nasty nasty hack handle properly...
					_fileHandle.seek(num * 6000, SEEK_CUR);
				}
			}
			
			if (!(_features & GF_AFTER_V8)) {
				_fileHandle.read(_classData, num * sizeof(uint32));

				// Swap flag endian where applicable
#if defined(SCUMM_BIG_ENDIAN)
				for (i = 0; i != num; i++)
					_classData[i] = FROM_LE_32(_classData[i]);
#endif
			}
			break;

		case MKID('RNAM'):
			_fileHandle.seek(itemsize - 8, SEEK_CUR);
			break;
		
		case MKID('DLFL'):
			_HEV7RoomOffsets = (byte *)calloc(itemsize - 8, 1);
			_fileHandle.read(_HEV7RoomOffsets, itemsize - 8);
			break;

		case MKID('DIRI'):
			num = _fileHandle.readUint16LE();
			_fileHandle.seek(num + (8 * num), SEEK_CUR);
			break;

		case MKID('ANAM'):
			_numAudioNames = _fileHandle.readUint16LE();
			_audioNames = (char*)malloc(_numAudioNames * 9);
			_fileHandle.read(_audioNames, _numAudioNames * 9);
			break;

		case MKID('DROO'):
			readResTypeList(rtRoom, MKID('ROOM'), "room");
			break;

		case MKID('DIRR'):
			readResTypeList(rtRoom, MKID('RMDA'), "room");
			break;

		case MKID('DRSC'):					// FIXME: Verify
			readResTypeList(rtRoomScripts, MKID('RMSC'), "room script");
			break;

		case MKID('DSCR'):
		case MKID('DIRS'):
			readResTypeList(rtScript, MKID('SCRP'), "script");
			break;

		case MKID('DCOS'):
		case MKID('DIRC'):
			readResTypeList(rtCostume, MKID('COST'), "costume");
			break;

		case MKID('MAXS'):
			readMAXS();
			break;

		case MKID('DSOU'):
			readResTypeList(rtSound, MKID('SOUN'), "sound");
			break;

		case MKID('DIRN'):
			readResTypeList(rtSound, MKID('DIRN'), "sound");
			break;

		case MKID('AARY'):
			debug(3, "Going to call readArrayFromIndexFile (pos = 0x%08x)", _fileHandle.pos());
			readArrayFromIndexFile();
			debug(3, "After readArrayFromIndexFile (pos = 0x%08x)", _fileHandle.pos());
			break;

		default:
			error("Bad ID %c%c%c%c found in directory!",
						(byte)blocktype,
						(byte)(blocktype >> 8),
						(byte)(blocktype >> 16),
						(byte)(blocktype >> 24));
			return;
		}
	}

//  if (numblock!=9)
//    error("Not enough blocks read from directory");

	closeRoom();
}

void Scumm::readArrayFromIndexFile() {
	int num;
	int a, b, c;

	if (_features & GF_AFTER_V8) {
		while ((num = _fileHandle.readUint32LE()) != 0) {
			a = _fileHandle.readUint32LE();
			b = _fileHandle.readUint32LE();
			
			// FIXME - seems the COMI scripts have a bug related to array 436.
			// and visible in script 2015, room 20. Basically, the dimensions
			// are swapped in the definition of the array, but its obvious
			// that this must be a script bug simply by looking at the defintions
			// of other arrays and how they are used.
			// Talk to fingolfin if you have questions about this :-)
			if (num == 436)
				defineArray(num, 5, b, a);
			else
				defineArray(num, 5, a, b);
		}
	} else {
		while ((num = _fileHandle.readUint16LE()) != 0) {
			a = _fileHandle.readUint16LE();
			b = _fileHandle.readUint16LE();
			c = _fileHandle.readUint16LE();
			if (c == 1)
				defineArray(num, 1, a, b);
			else
				defineArray(num, 5, a, b);
		}
	}
}

void Scumm::readResTypeList(int id, uint32 tag, const char *name) {
	int num;
	int i;

	debug(9, "readResTypeList(%s,%x,%s)", resTypeFromId(id), FROM_LE_32(tag), name);

	if (_features & GF_AFTER_V8)
		num = _fileHandle.readUint32LE();
	else if (!(_features & GF_OLD_BUNDLE))
		num = _fileHandle.readUint16LE();
	else
		num = _fileHandle.readByte();

	if (_features & GF_OLD_BUNDLE) {
		if (num >= 0xFF) {
			error("Too many %ss (%d) in directory", name, num);
		}
		allocResTypeData(id, tag, num, name, 1);
	} else {
		if (num != res.num[id]) {
			error("Invalid number of %ss (%d) in directory", name, num);
		}
	}

	if (_features & GF_OLD_BUNDLE) {
		if (id == rtRoom) {
			for (i = 0; i < num; i++)
				res.roomno[id][i] = i;
			_fileHandle.seek(num, SEEK_CUR);
		} else {
			for (i = 0; i < num; i++)
				res.roomno[id][i] = _fileHandle.readByte();
		}
		for (i = 0; i < num; i++) {
			res.roomoffs[id][i] = _fileHandle.readUint16LE();
			if (res.roomoffs[id][i] == 0xFFFF)
				res.roomoffs[id][i] = 0xFFFFFFFF;
		}

	} else if (_features & GF_SMALL_HEADER) {
		for (i = 0; i < num; i++) {
			res.roomno[id][i] = _fileHandle.readByte();
			res.roomoffs[id][i] = _fileHandle.readUint32LE();
		}
	} else {
		for (i = 0; i < num; i++) {
			res.roomno[id][i] = _fileHandle.readByte();
		}
		for (i = 0; i < num; i++) {
			res.roomoffs[id][i] = _fileHandle.readUint32LE();
		}
		if (_features & GF_AFTER_HEV7) {
			_fileHandle.seek(4 * num, SEEK_CUR); // FIXME what are these additional offsets
		}
	}
}

void Scumm::allocResTypeData(int id, uint32 tag, int num, const char *name, int mode) {
	debug(9, "allocResTypeData(%s/%s,%x,%d,%d)", resTypeFromId(id), name, FROM_LE_32(tag), num, mode);
	assert(id >= 0 && id < (int)(ARRAYSIZE(res.mode)));

	if (num >= 2000) {
		error("Too many %ss (%d) in directory", name, num);
	}

	res.mode[id] = mode;
	res.num[id] = num;
	res.tags[id] = tag;
	res.name[id] = name;
	res.address[id] = (byte **)calloc(num, sizeof(void *));
	res.flags[id] = (byte *)calloc(num, sizeof(byte));

	if (mode) {
		res.roomno[id] = (byte *)calloc(num, sizeof(byte));
		res.roomoffs[id] = (uint32 *)calloc(num, sizeof(uint32));
	}
}

void Scumm::loadCharset(int no) {
	int i;
	byte *ptr;

	debug(9, "loadCharset(%d)", no);

	/* FIXME - hack around crash in Indy4 (occurs if you try to load after dieing) */
	if (_gameId == GID_INDY4 && no == 0)
		no = 1;

	assert(no < (int)sizeof(_charsetData) / 16);
	checkRange(_maxCharsets - 1, 1, no, "Loading illegal charset %d");

//  ensureResourceLoaded(rtCharset, no);
	ptr = getResourceAddress(rtCharset, no);
	if (_features & GF_SMALL_HEADER)
		ptr -= 12;

	for (i = 0; i < 15; i++) {
		_charsetData[no][i + 1] = ptr[i + 14];
	}
}

void Scumm::nukeCharset(int i) {
	checkRange(_maxCharsets - 1, 1, i, "Nuking illegal charset %d");
	nukeResource(rtCharset, i);
}

void Scumm::ensureResourceLoaded(int type, int i) {
	void *addr = NULL;

	debug(9, "ensureResourceLoaded(%s,%d)", resTypeFromId(type), i);

	if (type == rtRoom && i > 0x7F && !(_features & GF_AFTER_V7)) {
		i = _resourceMapper[i & 0x7F];
	}

	// FIXME - TODO: This check used to be "i==0". However, that causes
	// problems when using this function to ensure charset 0 is loaded.
	// This is done for many games, e.g. Zak256 or Indy3 (EGA and VGA).
	// For now we restrict the check to anything which is not a charset.
	// Question: Why was this check like that in the first place?
	// Answer: costumes with an index of zero in the newer games at least.
	// TODO: determine why the heck anything would try to load a costume
	// with id 0. Is that "normal", or is it caused by yet another bug in
	// our code base? After all we also have to add special cases for many
	// of our script opcodes that check for the (invalid) actor 0... so 
	// maybe both issues are related...
	if (type != rtCharset && i == 0)
		return;

	if (i <= res.num[type])
		addr = res.address[type][i];

	if (addr)
		return;

	loadResource(type, i);

	if (!(_features & GF_AFTER_V7) && !(_features & GF_SMALL_HEADER))
		if (type == rtRoom && i == _roomResource)
			VAR(VAR_ROOM_FLAG) = 1;
}

int Scumm::loadResource(int type, int idx) {
	int roomNr;
	uint32 fileOffs;
	uint32 size, tag;

	debug(2, "loadResource(%s,%d)", resTypeFromId(type),idx);

	if (type == rtCharset && (_features & GF_SMALL_HEADER)) {
		loadCharset(idx);
		return (1);
	}

	roomNr = getResourceRoomNr(type, idx);

	if (idx >= res.num[type])
		error("%s %d undefined %d %d", res.name[type], idx, res.num[type], roomNr);

	if (roomNr == 0)
		roomNr = _roomResource;

	if (type == rtRoom) {
		if (_features & GF_AFTER_V8)
			fileOffs = 8;
		else
			fileOffs = 0;
	} else {
		fileOffs = res.roomoffs[type][idx];
		if (fileOffs == 0xFFFFFFFF)
			return 0;
	}

	openRoom(roomNr);

	_fileHandle.seek(fileOffs + _fileOffset, SEEK_SET);

	if (_features & GF_OLD_BUNDLE) {
		size = _fileHandle.readUint16LE();
		_fileHandle.seek(-2, SEEK_CUR);
	} else if (_features & GF_SMALL_HEADER) {
		if (!(_features & GF_SMALL_NAMES))
			_fileHandle.seek(8, SEEK_CUR);
		size = _fileHandle.readUint32LE();
		tag = _fileHandle.readUint16LE();
		_fileHandle.seek(-6, SEEK_CUR);
		/* FIXME */
		if ((type == rtSound) && (_gameId != GID_ZAK256)) {
			return readSoundResourceSmallHeader(type, idx);
		}
	} else {
		if (type == rtSound) {
			_fileHandle.readUint32LE();
			_fileHandle.readUint32LE();
			return readSoundResource(type, idx);
		}

		tag = fileReadDword();

		if (tag != res.tags[type]) {
			error("%s %d not in room %d at %d+%d in file %s",
					res.name[type], idx, roomNr,
					_fileOffset, fileOffs, _fileHandle.name());
		}

		size = _fileHandle.readUint32BE();
		_fileHandle.seek(-8, SEEK_CUR);
	}
	_fileHandle.read(createResource(type, idx, size), size);

	// dump the resource if requested
	if (_dumpScripts && type == rtScript) {
		dumpResource("script-", idx, getResourceAddress(rtScript, idx));
	}

	if (!_fileHandle.ioFailed()) {
		return 1;
	}

	nukeResource(type, idx);

	error("Cannot read resource");
}

int Scumm::readSoundResource(int type, int idx) {
	uint32 pos, total_size, size, tag, basetag;
	int pri, best_pri;
	uint32 best_size = 0, best_offs = 0;

	debug(9, "readSoundResource(%s,%d)", resTypeFromId(type), idx);

	pos = 0;

	basetag = fileReadDword();
	total_size = _fileHandle.readUint32BE();

	debug(8, "  basetag: %c%c%c%c, total_size=%d",
				(char)((basetag >> 24) & 0xff),
				(char)((basetag >> 16) & 0xff),
				(char)((basetag >> 8) & 0xff), (char)(basetag & 0xff), total_size);

	//if (_gameId == GID_SAMNMAX || _features & GF_AFTER_V7) {
	if (basetag == MKID('MIDI') || basetag == MKID('iMUS')) {
		_fileHandle.seek(-8, SEEK_CUR);
		_fileHandle.read(createResource(type, idx, total_size + 8), total_size + 8);
		return 1;
	} else if (basetag == MKID('SOU ')) {
		best_pri = -1;
		while (pos < total_size) {
			tag = fileReadDword();
			size = _fileHandle.readUint32BE() + 8;
			pos += size;

			pri = -1;

			switch (tag) {
			case MKID('SBL '):
				pri = 15;
				break;
			case MKID('ADL '):
				pri = 1;
				if (_use_adlib)
					pri = 10;
				break;
			case MKID('ROL '):
				pri = 3;
				break;
			case MKID('GMD '):
				pri = 4;
				break;
			case MKID('MAC '):
				pri = 2;
				break;
			case MKID('SPK '):
				pri = -1;
//				if (!_use_adlib)
//					pri = 0;
				break;
			}

			debug(8, "    tag: %c%c%c%c, total_size=%d, pri=%d",
						(char)((tag >> 24) & 0xff),
						(char)((tag >> 16) & 0xff), (char)((tag >> 8) & 0xff), (char)(tag & 0xff), size, pri);


			if (pri > best_pri) {
				best_pri = pri;
				best_size = size;
				best_offs = _fileHandle.pos();
			}

			_fileHandle.seek(size - 8, SEEK_CUR);
		}

		if (best_pri != -1) {
			_fileHandle.seek(best_offs - 8, SEEK_SET);
			_fileHandle.read(createResource(type, idx, best_size), best_size);
			return 1;
		}
	} else if (FROM_LE_32(basetag) == 24) {
		_fileHandle.seek(-12, SEEK_CUR);
		total_size = _fileHandle.readUint32BE();
		_fileHandle.seek(-8, SEEK_CUR);
		_fileHandle.read(createResource(type, idx, total_size), total_size);
		return 1;
	} else if (basetag == MKID('Mac0')) {
		debug(1, "Found base tag Mac0 in sound %d, size %d", idx, total_size);
		debug(1, "It was at position %d", _fileHandle.pos());

		/* Offset
		   0x14, 0x1C, 0x20, 0x24 - offsets of channel 1/2/3/4 chunk-
		   Each channel has tag "Chan", followed by its length. At the end
		   of each chan follows either an empty "Done" chunk (length 0) or an
		   empty "Loop" chunk. Maybe "Loop" indicates the song should be
		   played forever?!?.

		   There can be various different subchunks it seems. The
		   following combinations appear in Monkey Island:
		   100: ORGA, TROM, BASS, 
		   101: ORGA, SHAK, BASS, 
		   103: PIPE, PIPE, PIPE, 
		   104: VIBE, WHIS, BASS, 
		   108: ORGA, MARI, BASS, 
		   110: ORGA, SHAK, VIBE, 
		   111: MARI, SHAK, BASS, 
		   115: PLUC, SHAK, WHIS, 
		   One guess is that these are instrument names: Organ, Marimba, Whistle...
		   Maybe there is a mapping table someplace? Maybe these are even mapped to
		   Mac1 type "instruments" ?

		   What follows are four byte "commands" it seems, like this (hex):
		   01 68 4F 49
		   01 68 00 40
		   01 68 4F 49
		   ...
		   01 68 00 40
		   02 1C 5B 40
		   00 B4 00 40
		   ...
		   01 68 37 3C
		   00 18 37 38
		   04 20 3E 34
		   01 68 4A 3C

		   More data:
		   00 09 3E 10
		   01 5F 00 40
		   00 9C 36 40
		   00 CC 00 40
		   00 18 42 49
		   00 18 45 3C
		   01 29 4A 3C
		   00 0F 00 40

		   Maybe I am mistaken when I think it's four byte, some other parts
		   seem to suggest it's 2 byte oriented, or even variable length...
		 */
		_fileHandle.seek(-12, SEEK_CUR);
		total_size = _fileHandle.readUint32BE();
		_fileHandle.read(createResource(type, idx, total_size), total_size - 8);
		return 1;
	} else if (basetag == MKID('Mac1')) {
		_fileHandle.seek(-12, SEEK_CUR);
		total_size = _fileHandle.readUint32BE();
		_fileHandle.read(createResource(type, idx, total_size), total_size - 8);
		return 1;
	} else if (basetag == MKID('DIGI')) {
		// Use in Putt-Putt Demo
		debug(1, "Found base tag DIGI in sound %d, size %d", idx, total_size);
		debug(1, "It was at position %d", _fileHandle.pos());

		_fileHandle.seek(-12, SEEK_CUR);
		total_size = _fileHandle.readUint32BE();
		_fileHandle.read(createResource(type, idx, total_size), total_size - 8);
		return 1;
	} else if (basetag == MKID('Crea')) {
		_fileHandle.seek(-12, SEEK_CUR);
		total_size = _fileHandle.readUint32BE();
		_fileHandle.read(createResource(type, idx, total_size), total_size - 8);
		return 1;
	} else {
		fprintf(stderr, "WARNING: Unrecognized base tag 0x%08x in sound %d\n", basetag, idx);
	}
	res.roomoffs[type][idx] = 0xFFFFFFFF;
	return 0;
}

// FIXME: some default MIDI instruments for INDY3/MI1
static char OLD256_MIDI_HACK[] =
	// 0
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x00\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x00"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb0\x07\x64"      // Controller 7 = 100
	// 1
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x01\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x01"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb1\x07\x64"      // Controller 7 = 100
	// 2
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x02\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x02"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb2\x07\x64"      // Controller 7 = 100
	// 3
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x03\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x03"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb3\x07\x64"      // Controller 7 = 100
	// 4
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x04\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x04"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb4\x07\x64"      // Controller 7 = 100
	// 5
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x05\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x05"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb5\x07\x64"      // Controller 7 = 100
	// 6
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x06\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x06"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb6\x07\x64"      // Controller 7 = 100
	// 7
	"\x00\xf0\x14\x7d\x00"  // sysex 00: part on/off
	"\x07\x00\x03"          // part/channel
	"\x00\x00\x07\x0f\x00\x00\x08\x00\x00\x00\x00\x02\x00\x00\xf7"
	"\x04\xf0\x41\x7d\x10"  // sysex 16: set instrument
	"\x07"                  // part/channel
	"\x01\x06\x02\x0a\x08\x09\x0d\x08\x04\x04"
	"\x04\x06\x02\x02\x03\x07\x0f\x0d"
	"\x05\x04\x0c\x00\x03\x01\x01\x00"
	"\x00\x00\x01\x01\x0e\x00\x02\x02"
	"\x01\x00\x01\x00\x01\x02\x00\x01"
	"\x08\x00\x00\x00\x01\x02\x04\x00"
	"\x06\x02\x00\x00\x04\x00\x03\x02"
	"\x04\x00\x00\xf7"
	"\x00\xb7\x07\x64";     // Controller 7 = 100

int Scumm::readSoundResourceSmallHeader(int type, int idx) {
	uint32 pos, total_size, size, dw, tag;
	uint32 best_size = 0, best_offs = 0;

	debug(4, "readSoundResourceSmallHeader(%s,%d)", resTypeFromId(type), idx);

	//if (_rescache->readResource(roomNr, type, idx))
	//		return 1;

	total_size = size = _fileHandle.readUint32LE();
	tag = _fileHandle.readUint16LE();
	debug(4, "  tag='%c%c', size=%d",
					(char) (tag & 0xff),
					(char) ((tag >> 8) & 0xff), size);

	pos = 6;
	while (pos < total_size) {
		size = _fileHandle.readUint32LE();
		tag = _fileHandle.readUint16LE();
		debug(4, "  tag='%c%c', size=%d",
					(char) (tag & 0xff),
					(char) ((tag >> 8) & 0xff), size);
		pos += size;

		// MI1 and Indy3 uses one or more nested SO resources, which contains AD and WA
		// resources.
		if ((tag == 0x4441) && !(best_offs)) { // AD
				best_size = size;
				best_offs = _fileHandle.pos();
		} else { // other AD, WA and nested SO resources
			if (tag == 0x4F53) {
				pos -= size;
				size = 6;
				pos += 6;
			}
		}
		_fileHandle.seek(size - 6, SEEK_CUR);
	}

	// AD resources have a header, instrument definitions and one MIDI track.
	// We build an 'ADL ' resource from that:
	//   8 bytes resource header
	//  16 bytes MDhd header
	//  14 bytes MThd header
	//   8 bytes MTrk header
	//   7 bytes MIDI tempo sysex
	//     + some default instruments
	// TODO:  - make some real MIDI instrument definitions
	//        - proper handling of the short (non-music, SFX) AD resources format
	//        - check the LE/BE handling for platforms other than PC

	if (best_offs != 0) {
		byte *ptr, *track, *instr;
		byte ticks, play_once;
		byte music_type, num_instr;

		_fileHandle.seek(best_offs - 6, SEEK_SET);

		ptr = createResource(type, idx, best_size);
		_fileHandle.read(ptr, best_size);

		music_type = *(ptr + 8);	// 0x80: is music; otherwise not.
		
		if (music_type != 0x80) {
			// It's an SFX; we don't know how to handle those yet
			debug(4, "Sound %d not played, format not yet supported", idx);
			nukeResource(type, idx);
			res.roomoffs[type][idx] = 0xFFFFFFFF;
			return 0;
		}
		
		// The "speed" of the song
		ticks = *(ptr + 9);
		
		// Flag that tells us whether we should loop the song (0) or play it only once (1)
		play_once = *(ptr + 10);
		
		// Number of instruments used
		num_instr = *(ptr + 16);	// Normally 8
		if (num_instr != 8)
			warning("Sound %d has %d instruments, expected 8", idx, num_instr);

		// copy the instrument data in another memory area
		instr = (byte *)calloc(8 * 16, 1);
		assert(instr);
		memcpy(instr, ptr + 0x19, 8*16);

		// skip over the rest of the header and copy the MIDI data into a buffer
		size = best_size;
		ptr  += 0x19 + 8 * 16;
		size -= 0x19 + 8 * 16;
		CHECK_HEAP 
		track = (byte *)calloc(size, 1);
		if (track == NULL) {
			error("Out of memory while allocating %d", size);
		}
		memcpy(track, ptr, size);         // saving MIDI track data

		// Now nuke the old resource, and replace it with a new one
		nukeResource(type, idx);
		total_size = 8 + 16 + 14 + 8 + 7 + sizeof(OLD256_MIDI_HACK) + size;
		if (!play_once)
			total_size += 20;	// Up to 20 additional bytes are needed for the jump sysex

		// Write the ADL header (see also above for more information)
		ptr = createResource(type, idx, total_size);
		memcpy(ptr, "ADL ", 4); ptr += 4;
		dw = READ_BE_UINT32(&total_size);
		memcpy(ptr, &dw, 4); ptr += 4;
		memcpy(ptr, "MDhd", 4); ptr += 4;
		ptr[0] = 0; ptr[1] = 0; ptr[2] = 0; ptr[3] = 8;
		ptr += 4;
		memset(ptr, 0, 8), ptr += 8;
		memcpy(ptr, "MThd", 4); ptr += 4;
		ptr[0] = 0; ptr[1] = 0; ptr[2] = 0; ptr[3] = 6;
		ptr += 4;
		ptr[0] = 0; ptr[1] = 0; ptr[2] = 0; ptr[3] = 1; // MIDI format 0 with 1 track
		ptr += 4;

		// We will ignore the PPQN in the original resource, because
		// it's invalid anyway. We use a constant PPQN of 480.
		// memcpy(ptr, &ticks, 2); ptr += 2;
		*ptr++ = 480 >> 8;
		*ptr++ = 480 & 0xFF;

		memcpy(ptr, "MTrk", 4); ptr += 4;
		*ptr++ = ((sizeof(OLD256_MIDI_HACK) + size + 7) >> 24) & 0xFF;
		*ptr++ = ((sizeof(OLD256_MIDI_HACK) + size + 7) >> 16) & 0xFF;
		*ptr++ = ((sizeof(OLD256_MIDI_HACK) + size + 7) >>  8) & 0xFF;
		*ptr++ = ((sizeof(OLD256_MIDI_HACK) + size + 7)      ) & 0xFF;

		// Conver the ticks into a MIDI tempo. 
		dw = (500000 * 256) / ticks;
		debug(4, "  ticks = %d, speed = %ld", ticks, dw);
		
		// Write a tempo change SysEx
		memcpy(ptr, "\x00\xFF\x51\x03", 4); ptr += 4;
		*ptr++ = (byte)((dw >> 16) & 0xFF);
		*ptr++ = (byte)((dw >> 8) & 0xFF);
		*ptr++ = (byte)(dw & 0xFF);

		// Copy our hardcoded instrument table into it
		// Then, convert the instrument table as given in this song resource
		// And write it *over* the hardcoded table.
		// Note: we deliberately.
		memcpy(ptr, OLD256_MIDI_HACK, sizeof(OLD256_MIDI_HACK));

		
		/* now fill in the instruments */
		for (int i = 0; i < 8; i++) {

			/* flags_1 */
			ptr[95 * i + 30 + 0] = (instr[i * 16 + 3] >> 4) & 0xf;
			ptr[95 * i + 30 + 1] = instr[i * 16 + 3] & 0xf;

			/* oplvl_1 */
			ptr[95 * i + 30 + 2] = (instr[i * 16 + 4] >> 4) & 0xf;
			ptr[95 * i + 30 + 3] = instr[i * 16 + 4] & 0xf;

			/* atdec_1 */
			ptr[95 * i + 30 + 4] = ((~instr[i * 16 + 5]) >> 4) & 0xf;
			ptr[95 * i + 30 + 5] = (~instr[i * 16 + 5]) & 0xf;

			/* sustrel_1 */
			ptr[95 * i + 30 + 6] = ((~instr[i * 16 + 6]) >> 4) & 0xf;
			ptr[95 * i + 30 + 7] = (~instr[i * 16 + 6]) & 0xf;

			/* waveform_1 */
			ptr[95 * i + 30 + 8] = (instr[i * 16 + 7] >> 4) & 0xf;
			ptr[95 * i + 30 + 9] = instr[i * 16 + 7] & 0xf;

			/* flags_2 */
			ptr[95 * i + 30 + 10] = (instr[i * 16 + 8] >> 4) & 0xf;
			ptr[95 * i + 30 + 11] = instr[i * 16 + 8] & 0xf;

			/* oplvl_2 */
			ptr[95 * i + 30 + 12] = 3;
			ptr[95 * i + 30 + 13] = 0xF;

			/* atdec_2 */
			ptr[95 * i + 30 + 14] = ((~instr[i * 16 + 10]) >> 4) & 0xf;
			ptr[95 * i + 30 + 15] = (~instr[i * 16 + 10]) & 0xf;

			/* sustrel_2 */
			ptr[95 * i + 30 + 16] = ((~instr[i * 16 + 11]) >> 4) & 0xf;
			ptr[95 * i + 30 + 17] = (~instr[i * 16 + 11]) & 0xf;

			/* waveform_2 */
			ptr[95 * i + 30 + 18] = (instr[i * 16 + 12] >> 4) & 0xf;
			ptr[95 * i + 30 + 19] = instr[i * 16 + 12] & 0xf;

			/* feedback */
			ptr[95 * i + 30 + 20] = (instr[i * 16 + 2] >> 4) & 0xf;
			ptr[95 * i + 30 + 21] = instr[i * 16 + 2] & 0xf;
		}

		free(instr);
		ptr += sizeof(OLD256_MIDI_HACK);

		// Now copy the actual music data 
		memcpy(ptr, track, size);
		free(track);
		
		if (!play_once) {
			// The song is meant to be looped. We achieve this by inserting just
			// before the song end a jump to the song start. More precisely we abuse
			// a S&M sysex, "maybe_jump" to achieve this effect. We could also
			// use a set_loop sysex, but it's a bit longer, a little more complicated,
			// and seemingly has no advantage either.

			// First, find the track end
			byte *end = ptr + size;
			for (; ptr < end; ptr++) {
				if (*ptr == 0xff && *(ptr + 1) == 0x2f)
					break;
			}
			assert(ptr < end);

			// Now insert the jump. The jump offset is measure in ticks, and 
			// each instrument definition spans 4 ticks... so we jump to tick
			// 8*4, although jumping to tick 0 would probably work fine, too.
			// Note: it's possible that some musics don't loop from the start...
			// in that case we'll have to figure out how the loop range is specified
			// and then how to handle it appropriately (if it's specified in
			// ticks, we are fine; but if it's byte offset, we'll have to work
			// a bit...).
			int jump_offset = 8 * 4;
			memcpy(ptr, "\xf0\x13\x7d\x30\00", 5); ptr += 5;	// maybe_jump
			memcpy(ptr, "\x00\x00", 2); ptr += 2;			// cmd -> 0 means always jump
			memcpy(ptr, "\x00\x00\x00\x00", 4); ptr += 4;	// track -> there is only one track, 0
			memcpy(ptr, "\x00\x00\x00\x00", 4); ptr += 4;	// beat -> for now, 0
			// Ticks
			*ptr++ = (byte)((jump_offset >> 12) & 0x0F);
			*ptr++ = (byte)((jump_offset >> 8) & 0x0F);
			*ptr++ = (byte)((jump_offset >> 4) & 0x0F);
			*ptr++ = (byte)(jump_offset & 0x0F);
			memcpy(ptr, "\x00\xf7", 2); ptr += 2;	// sysex end marker

			// Finally we reinsert the end of song sysex, just in case
			memcpy(ptr, "\x00\xff\x21", 3); ptr += 3;
		}
		
		return 1;
	}
	res.roomoffs[type][idx] = 0xFFFFFFFF;
	return 0;
}


int Scumm::getResourceRoomNr(int type, int idx) {
	if (type == rtRoom)
		return idx;
	return res.roomno[type][idx];
}

byte *Scumm::getResourceAddress(int type, int idx) {
	byte *ptr;

	CHECK_HEAP
	if (!validateResource("getResourceAddress", type, idx))
		return NULL;

	if (!res.address[type]) {
		debug(9, "getResourceAddress(%s,%d), res.address[type] == NULL", resTypeFromId(type), idx);
		return NULL;
	}

	if (res.mode[type] && !res.address[type][idx]) {
		ensureResourceLoaded(type, idx);
	}

	if (!(ptr = (byte *)res.address[type][idx])) {
		debug(9, "getResourceAddress(%s,%d) == NULL", resTypeFromId(type), idx);
		return NULL;
	}

	setResourceCounter(type, idx, 1);

	debug(9, "getResourceAddress(%s,%d) == %ld", resTypeFromId(type), idx, ptr + sizeof(MemBlkHeader));
	return ptr + sizeof(MemBlkHeader);
}

byte *Scumm::getStringAddress(int i) {
	byte *b = getResourceAddress(rtString, i);
	if (!b)
		return NULL;

	if (_features & GF_NEW_OPCODES)
		return ((ArrayHeader *)b)->data;
	return b;
}

byte *Scumm::getStringAddressVar(int i) {
	byte *addr;

	addr = getResourceAddress(rtString, _scummVars[i]);
	if (addr == NULL)
		// as this is used for string mapping in the gui
		// it must be allowed to return NULL
		// error("NULL string var %d slot %d", i, _scummVars[i]);
		return NULL;

	if (_features & GF_NEW_OPCODES)
		return ((ArrayHeader *)addr)->data;

	return (addr);
}

void Scumm::setResourceCounter(int type, int idx, byte flag) {
	res.flags[type][idx] &= ~RF_USAGE;
	res.flags[type][idx] |= flag;
}

/* 2 bytes safety area to make "precaching" of bytes in the gdi drawer easier */
#define SAFETY_AREA 2

byte *Scumm::createResource(int type, int idx, uint32 size) {
	byte *ptr;

	CHECK_HEAP
	debug(9, "createResource(%s,%d,%d)", resTypeFromId(type), idx, size);

	if (!validateResource("allocating", type, idx))
		return NULL;
	nukeResource(type, idx);

	expireResources(size);

	CHECK_HEAP
	ptr = (byte *)calloc(size + sizeof(MemBlkHeader) + SAFETY_AREA, 1);
	if (ptr == NULL) {
		error("Out of memory while allocating %d", size);
	}

	_allocatedSize += size;

	res.address[type][idx] = ptr;
	((MemBlkHeader *)ptr)->size = size;
	setResourceCounter(type, idx, 1);
	return ptr + sizeof(MemBlkHeader);	/* skip header */
}

bool Scumm::validateResource(const char *str, int type, int idx) {
	if (type < rtFirst || type > rtLast || (uint) idx >= (uint) res.num[type]) {
		warning("%s Illegal Glob type %s (%d) num %d", str, resTypeFromId(type), type, idx);
		return false;
	}
	return true;
}

void Scumm::nukeResource(int type, int idx) {
	byte *ptr;

	CHECK_HEAP
	if (!res.address[type])
		return;

	assert(idx >= 0 && idx < res.num[type]);

	if ((ptr = res.address[type][idx]) != NULL) {
		debug(9, "nukeResource(%s,%d)", resTypeFromId(type), idx);
		res.address[type][idx] = 0;
		res.flags[type][idx] = 0;
		_allocatedSize -= ((MemBlkHeader *)ptr)->size;
		free(ptr);
	}
}

byte *Scumm::findResourceData(uint32 tag, byte *ptr) {
	if (_features & GF_OLD_BUNDLE)
		error("findResourceData must not be used in GF_OLD_BUNDLE games");
	else if (_features & GF_SMALL_HEADER)
		ptr = findResourceSmall(tag, ptr, 0);
	else
		ptr = findResource(tag, ptr, 0);

	if (ptr == NULL)
		return NULL;
	return ptr + _resourceHeaderSize;
}

int Scumm::getResourceDataSize(byte *ptr) {
	if (ptr == NULL)
		return 0;

	if (_features & GF_OLD_BUNDLE)
		return READ_LE_UINT16(ptr) - 4;
	else if (_features & GF_SMALL_HEADER)
		return READ_LE_UINT32(ptr) - 6;
	else
		return READ_BE_UINT32_UNALIGNED(ptr - 4) - 8;
}

struct FindResourceState {
	uint32 size, pos;
	byte *ptr;
};

/* just O(N) complexity when iterating with this function */
byte *findResource(uint32 tag, byte *searchin) {
	uint32 size;
	static FindResourceState frs;
	FindResourceState *f = &frs;	/* easier to make it thread safe like this */

	if (searchin) {
		f->size = READ_BE_UINT32_UNALIGNED(searchin + 4);
		f->pos = 8;
		f->ptr = searchin + 8;
		goto StartScan;
	}

	do {
		size = READ_BE_UINT32_UNALIGNED(f->ptr + 4);
		if ((int32)size <= 0)
			return NULL;

		f->pos += size;
		f->ptr += size;

	StartScan:
		if (f->pos >= f->size)
			return NULL;
	} while (READ_UINT32_UNALIGNED(f->ptr) != tag);

	return f->ptr;
}

byte *findResourceSmall(uint32 tag, byte *searchin) {
	uint32 size;
	static FindResourceState frs;
	FindResourceState *f = &frs;	/* easier to make it thread safe like this */
	uint16 smallTag;

	smallTag = newTag2Old(tag);

	if (searchin) {
		f->size = READ_LE_UINT32(searchin);
		f->pos = 6;
		f->ptr = searchin + 6;
		goto StartScan;
	}

	do {
		size = READ_LE_UINT32(f->ptr);
		if ((int32)size <= 0)
			return NULL;

		f->pos += size;
		f->ptr += size;

	StartScan:
		if (f->pos >= f->size)
			return NULL;
	} while (READ_LE_UINT16(f->ptr + 4) != smallTag);

	return f->ptr;
}

byte *findResource(uint32 tag, byte *searchin, int idx) {
	uint32 curpos, totalsize, size;

	assert(searchin);

	searchin += 4;
	totalsize = READ_BE_UINT32_UNALIGNED(searchin);
	curpos = 8;
	searchin += 4;

	while (curpos < totalsize) {
		if (READ_UINT32_UNALIGNED(searchin) == tag && !idx--)
			return searchin;

		size = READ_BE_UINT32_UNALIGNED(searchin + 4);
		if ((int32)size <= 0) {
			error("(%c%c%c%c) Not found in %d... illegal block len %d",
						tag & 0xFF, (tag >> 8) & 0xFF, (tag >> 16) & 0xFF, (tag >> 24) & 0xFF, 0, size);
			return NULL;
		}

		curpos += size;
		searchin += size;
	}

	return NULL;
}

byte *findResourceSmall(uint32 tag, byte *searchin, int idx) {
	uint32 curpos, totalsize, size;
	uint16 smallTag;

	smallTag = newTag2Old(tag);

	assert(searchin);

	totalsize = READ_LE_UINT32(searchin);
	searchin += 6;
	curpos = 6;

	while (curpos < totalsize) {
		size = READ_LE_UINT32(searchin);

		if (READ_LE_UINT16(searchin + 4) == smallTag && !idx--)
			return searchin;

		if ((int32)size <= 0) {
			error("(%c%c%c%c) Not found in %d... illegal block len %d",
						tag & 0xFF, (tag >> 8) & 0xFF, (tag >> 16) & 0xFF, (tag >> 24) & 0xFF, 0, size);
			return NULL;
		}

		curpos += size;
		searchin += size;
	}

	return NULL;
}

void Scumm::lock(int type, int i) {
	if (!validateResource("Locking", type, i))
		return;
	res.flags[type][i] |= RF_LOCK;

//  debug(1, "locking %d,%d", type, i);
}

void Scumm::unlock(int type, int i) {
	if (!validateResource("Unlocking", type, i))
		return;
	res.flags[type][i] &= ~RF_LOCK;

//  debug(1, "unlocking %d,%d", type, i);
}

bool Scumm::isResourceInUse(int type, int i)
{
	if (!validateResource("isResourceInUse", type, i))
		return false;
	switch (type) {
	case rtRoom:
		return _roomResource == (byte)i;
	case rtRoomScripts:
		return _roomResource == (byte)i;
	case rtScript:
		return isScriptInUse(i);
	case rtCostume:
		return isCostumeInUse(i);
	case rtSound:
		return _sound->isSoundActive(i);
	default:
		return false;
	}
}

void Scumm::increaseResourceCounter() {
	int i, j;
	byte counter;

	for (i = rtFirst; i <= rtLast; i++) {
		for (j = res.num[i]; --j >= 0;) {
			counter = res.flags[i][j] & RF_USAGE;
			if (counter && counter < RF_USAGE_MAX) {
				setResourceCounter(i, j, counter + 1);
			}
		}
	}
}

void Scumm::expireResources(uint32 size) {
	int i, j;
	byte flag;
	byte best_counter;
	int best_type, best_res = 0;
	uint32 oldAllocatedSize;

//  return;

	if (_expire_counter != 0xFF) {
		_expire_counter = 0xFF;
		increaseResourceCounter();
	}

	if (size + _allocatedSize < _maxHeapThreshold)
		return;

	oldAllocatedSize = _allocatedSize;

	do {
		best_type = 0;
		best_counter = 2;

		for (i = rtFirst; i <= rtLast; i++)
			if (res.mode[i]) {
				for (j = res.num[i]; --j >= 0;) {
					flag = res.flags[i][j];
					if (!(flag & RF_LOCK) && flag >= best_counter && res.address[i][j] && !isResourceInUse(i, j)) {
						best_counter = flag;
						best_type = i;
						best_res = j;
					}
				}
			}

		if (!best_type)
			break;
		nukeResource(best_type, best_res);
	} while (size + _allocatedSize > _minHeapThreshold);

	increaseResourceCounter();

	debug(5, "Expired resources, mem %d -> %d", oldAllocatedSize, _allocatedSize);
}

void Scumm::freeResources() {
	int i, j;
	for (i = rtFirst; i <= rtLast; i++) {
		for (j = res.num[i]; --j >= 0;) {
			if (isResourceLoaded(i, j))
				nukeResource(i, j);
		}
		free(res.address[i]);
		free(res.flags[i]);
		free(res.roomno[i]);
		free(res.roomoffs[i]);
	}
}

void Scumm::loadPtrToResource(int type, int resindex, const byte *source) {
	byte *alloced;
	int i, len;

	nukeResource(type, resindex);

	len = resStrLen(source) + 1;

	if (len <= 0)
		return;

	alloced = createResource(type, resindex, len);

	if (!source) {
		alloced[0] = fetchScriptByte();
		for (i = 1; i < len; i++)
			alloced[i] = *_scriptPointer++;
	} else {
		for (i = 0; i < len; i++)
			alloced[i] = source[i];
	}
}

bool Scumm::isResourceLoaded(int type, int idx) {
	if (!validateResource("isLoaded", type, idx))
		return false;
	return res.address[type][idx] != NULL;
}

void Scumm::resourceStats() {
	int i, j;
	uint32 lockedSize = 0, lockedNum = 0;
	byte flag;

	for (i = rtFirst; i <= rtLast; i++)
		for (j = res.num[i]; --j >= 0;) {
			flag = res.flags[i][j];
			if (flag & RF_LOCK && res.address[i][j]) {
				lockedSize += ((MemBlkHeader *)res.address[i][j])->size;
				lockedNum++;
			}
		}

	debug(1, "Total allocated size=%d, locked=%d(%d)\n", _allocatedSize, lockedSize, lockedNum);
}

void Scumm::readMAXS() {
	if (_features & GF_AFTER_V8) {                    // CMI
		_fileHandle.seek(50 + 50, SEEK_CUR);            // 176 - 8
		_numVariables = _fileHandle.readUint32LE();     // 1500
		_numBitVariables = _fileHandle.readUint32LE();  // 2048
		_fileHandle.readUint32LE();                     // 40
		_numScripts = _fileHandle.readUint32LE();       // 458
		_numSounds = _fileHandle.readUint32LE();        // 789
		_numCharsets = _fileHandle.readUint32LE();      // 1
		_numCostumes = _fileHandle.readUint32LE();      // 446
		_numRooms = _fileHandle.readUint32LE();         // 95
		_fileHandle.readUint32LE();                     // 80
		_numGlobalObjects = _fileHandle.readUint32LE(); // 1401
		_fileHandle.readUint32LE();                     // 60
		_numLocalObjects = _fileHandle.readUint32LE();  // 200
		_numNewNames = _fileHandle.readUint32LE();      // 100
		_numFlObject = _fileHandle.readUint32LE();      // 128
		_numInventory = _fileHandle.readUint32LE();     // 80
		_numArray = _fileHandle.readUint32LE();         // 200
		_numVerbs = _fileHandle.readUint32LE();         // 50

		_objectRoomTable = (byte *)calloc(_numGlobalObjects, 1);
		_numGlobalScripts = 2000;

		_shadowPaletteSize = NUM_SHADOW_PALETTE * 256;
	} else if (_features & GF_AFTER_V7) {
		_fileHandle.seek(50 + 50, SEEK_CUR);
		_numVariables = _fileHandle.readUint16LE();
		_numBitVariables = _fileHandle.readUint16LE();
		_fileHandle.readUint16LE();                      // 40 in FT; 16 in Dig
		_numGlobalObjects = _fileHandle.readUint16LE();
		_numLocalObjects = _fileHandle.readUint16LE();
		_numNewNames = _fileHandle.readUint16LE();
		_numVerbs = _fileHandle.readUint16LE();
		_numFlObject = _fileHandle.readUint16LE();
		_numInventory = _fileHandle.readUint16LE();
		_numArray = _fileHandle.readUint16LE();
		_numRooms = _fileHandle.readUint16LE();
		_numScripts = _fileHandle.readUint16LE();
		_numSounds = _fileHandle.readUint16LE();
		_numCharsets = _fileHandle.readUint16LE();
		_numCostumes = _fileHandle.readUint16LE();

		_objectRoomTable = (byte *)calloc(_numGlobalObjects, 1);
		_numGlobalScripts = 2000;

		_shadowPaletteSize = NUM_SHADOW_PALETTE * 256;
	} else if (_features & GF_AFTER_V6) {
		_numVariables = _fileHandle.readUint16LE();
		_fileHandle.readUint16LE();                      // 16 in Sam/DOTT
		_numBitVariables = _fileHandle.readUint16LE();
		_numLocalObjects = _fileHandle.readUint16LE();
		_numArray = _fileHandle.readUint16LE();
		_fileHandle.readUint16LE();                      // 0 in Sam/DOTT
		_numVerbs = _fileHandle.readUint16LE();
		_numFlObject = _fileHandle.readUint16LE();
		_numInventory = _fileHandle.readUint16LE();
		_numRooms = _fileHandle.readUint16LE();
		_numScripts = _fileHandle.readUint16LE();
		_numSounds = _fileHandle.readUint16LE();
		_numCharsets = _fileHandle.readUint16LE();
		_numCostumes = _fileHandle.readUint16LE();
		_numGlobalObjects = _fileHandle.readUint16LE();
		_numNewNames = 50;

		_objectRoomTable = NULL;
		_numGlobalScripts = 200;

		_shadowPaletteSize = 256;
	} else {
		_numVariables = _fileHandle.readUint16LE();      // 800
		_fileHandle.readUint16LE();                      // 16
		_numBitVariables = _fileHandle.readUint16LE();   // 2048
		_numLocalObjects = _fileHandle.readUint16LE();   // 200
		_numArray = 50;
		_numVerbs = 100;
		_numNewNames = 0;
		_objectRoomTable = NULL;

		_fileHandle.readUint16LE();                      // 50
		_numCharsets = _fileHandle.readUint16LE();       // 9
		_fileHandle.readUint16LE();                      // 100
		_fileHandle.readUint16LE();                      // 50
		_numInventory = _fileHandle.readUint16LE();      // 80
		_numGlobalScripts = 200;

		_shadowPaletteSize = 256;

		_numFlObject = 50;
	}

	if (_shadowPaletteSize)
		_shadowPalette = (byte *)calloc(_shadowPaletteSize, 1);

	allocateArrays();
	_dynamicRoomOffsets = 1;
}

void Scumm::allocateArrays() {
	// Note: Buffers are now allocated in scummMain to allow for
	//     early GUI init.

	_objectOwnerTable = (byte *)calloc(_numGlobalObjects, 1);
	_objectStateTable = (byte *)calloc(_numGlobalObjects, 1);
	_classData = (uint32 *)calloc(_numGlobalObjects, sizeof(uint32));
	_arrays = (byte *)calloc(_numArray, 1);
	_newNames = (uint16 *)calloc(_numNewNames, sizeof(uint16));

	_inventory = (uint16 *)calloc(_numInventory, sizeof(uint16));
	_verbs = (VerbSlot *)calloc(_numVerbs, sizeof(VerbSlot));
	_objs = (ObjectData *)calloc(_numLocalObjects, sizeof(ObjectData));
	debug(2, "Allocated %d space in numObjects\n", _numLocalObjects);
	_scummVars = (int32 *)calloc(_numVariables, sizeof(int32));
	_bitVars = (byte *)calloc(_numBitVariables >> 3, 1);

	allocResTypeData(rtCostume, (_features & GF_NEW_COSTUMES) ? MKID('AKOS') : MKID('COST'),
								_numCostumes, "costume", 1);
	allocResTypeData(rtRoom, MKID('ROOM'), _numRooms, "room", 1);
	allocResTypeData(rtRoomScripts, MKID('RMSC'), _numRooms, "room script", 1);
	allocResTypeData(rtSound, MKID('SOUN'), _numSounds, "sound", 1);
	allocResTypeData(rtScript, MKID('SCRP'), _numScripts, "script", 1);
	allocResTypeData(rtCharset, MKID('CHAR'), _numCharsets, "charset", 1);
	allocResTypeData(rtObjectName, MKID('NONE'), _numNewNames, "new name", 0);
	allocResTypeData(rtInventory, MKID('NONE'), _numInventory, "inventory", 0);
	allocResTypeData(rtTemp, MKID('NONE'), 10, "temp", 0);
	allocResTypeData(rtScaleTable, MKID('NONE'), 5, "scale table", 0);
	allocResTypeData(rtActorName, MKID('NONE'), _numActors, "actor name", 0);
	allocResTypeData(rtVerb, MKID('NONE'), _numVerbs, "verb", 0);
	allocResTypeData(rtString, MKID('NONE'), _numArray, "array", 0);
	allocResTypeData(rtFlObject, MKID('NONE'), _numFlObject, "flobject", 0);
	allocResTypeData(rtMatrix, MKID('NONE'), 10, "boxes", 0);
}


bool Scumm::isGlobInMemory(int type, int idx) {
	if (!validateResource("isGlobInMemory", type, idx))
		return false;

	return res.address[type][idx] != NULL;
}

uint16 newTag2Old(uint32 oldTag) {
	switch (oldTag) {
	case (MKID('RMHD')):
		return (0x4448);	// HD
		break;
	case (MKID('IM00')):
		return (0x4D42);	// BM
		break;
	case (MKID('EXCD')):
		return (0x5845);	// EX
		break;
	case (MKID('ENCD')):
		return (0x4E45);	// EN
		break;
	case (MKID('SCAL')):
		return (0x4153);	// SA
		break;
	case (MKID('LSCR')):
		return (0x534C);	// LS
		break;
	case (MKID('OBCD')):
		return (0x434F);	// OC
		break;
	case (MKID('OBIM')):
		return (0x494F);	// OI
		break;
	case (MKID('SMAP')):
		return (0x4D42);	// BM
		break;
	case (MKID('CLUT')):
		return (0x4150);	// PA
		break;
	case (MKID('BOXD')):
		return (0x5842);	// BX
		break;
	default:
		return (0);
	}
}

char *Scumm::resTypeFromId(int id) {
	static char buf[100];

	switch (id) {
	case rtRoom:
		sprintf(buf, "Room");
		break;
	case rtScript:
		sprintf(buf, "Script");
		break;
	case rtCostume:
		sprintf(buf, "Costume");
		break;
	case rtSound:
		sprintf(buf, "Sound");
		break;
	case rtInventory:
		sprintf(buf, "Inventory");
		break;
	case rtCharset:
		sprintf(buf, "Charset");
		break;
	case rtString:
		sprintf(buf, "String");
		break;
	case rtVerb:
		sprintf(buf, "Verb");
		break;
	case rtActorName:
		sprintf(buf, "ActorName");
		break;
	case rtBuffer:
		sprintf(buf, "Buffer");
		break;
	case rtScaleTable:
		sprintf(buf, "ScaleTable");
		break;
	case rtTemp:
		sprintf(buf, "Temp");
		break;
	case rtFlObject:
		sprintf(buf, "FlObject");
		break;
	case rtMatrix:
		sprintf(buf, "Matrix");
		break;
	case rtBox:
		sprintf(buf, "Box");
		break;
	case rtLast:
		sprintf(buf, "Last");
		break;
	case rtNumTypes:
		sprintf(buf, "NumTypes");
		break;
	default:
		sprintf(buf, "%d", id);
	}
	return buf;
}