scummvm/scumm/string.cpp

/* 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 "actor.h"
#include "charset.h"
#include "dialogs.h"
#include "verbs.h"
#include "scumm/sound.h"

void Scumm::unkMessage1() {
	byte buffer[100];
	_msgPtrToAdd = buffer;
	_messagePtr = addMessageToStack(_messagePtr);

//	if ((_gameId == GID_CMI) && _debugMode) {	// In CMI, unkMessage1 is used for printDebug output
	if ((buffer[0] != 0xFF) && _debugMode) {
		debug(0, "DEBUG: %s", buffer);
		return;
	}

	if (buffer[0] == 0xFF && buffer[1] == 10) {
		uint32 a, b;

		a = buffer[2] | (buffer[3] << 8) | (buffer[6] << 16) | (buffer[7] << 24);
		b = buffer[10] | (buffer[11] << 8) | (buffer[14] << 16) | (buffer[15] << 24);

		// Sam and Max uses a caching system, printing empty messages
		// and setting VAR_V6_SOUNDMODE beforehand. See patch 609791.
		// FIXME: There are other VAR_V6_SOUNDMODE states, as
		// mentioned in the patch. FIXME after iMUSE is done.
		if (_gameId != GID_SAMNMAX || (VAR(VAR_V6_SOUNDMODE) != 2))
			_sound->talkSound(a, b, 1, -1);
	} 
}

void Scumm::unkMessage2() {
	byte buf[100];
	const byte *tmp;

	_msgPtrToAdd = buf;
	tmp = _messagePtr = addMessageToStack(_messagePtr);

	if (_string[3].color == 0)
		_string[3].color = 4;

	InfoDialog* dialog = new InfoDialog(_newgui, this, (char*)buf);
	// FIXME: I know this is the right thing to do for MI1 and MI2. For
	// all other games it's just a guess.
	VAR(VAR_KEYPRESS) = runDialog (dialog);
	delete dialog;

	_messagePtr = tmp;
}

void Scumm::CHARSET_1() {
	uint32 talk_sound_a = 0;
	uint32 talk_sound_b = 0;
	int s, i, t, c;
	int frme = -1;
	Actor *a;
	byte *buffer;
	bool has_talk_sound = false;
	bool has_anim = false;

	if (!_haveMsg)
		return;

	// FIXME: This Zak check fixes several hangs (Yak hang, and opening
	// 'secret room while walking' hang. It doesn't do the camera check
	// when the talk target isn't an actor. The question is, can we make
	// this a more general case? Does it really need to be Zak specific?
	if (!(_features & GF_AFTER_V7) && !(_gameId==GID_ZAK256 && VAR(VAR_TALK_ACTOR) == 0xFF)) {
		if ((camera._dest.x >> 3) != (camera._cur.x >> 3) || camera._cur.x != camera._last.x)
			return;
	}

	a = NULL;
	if (VAR(VAR_TALK_ACTOR) != 0xFF)
		a = derefActorSafe(VAR(VAR_TALK_ACTOR), "CHARSET_1");

	if (a && _string[0].overhead != 0) {
		if (!(_features & GF_AFTER_V6)) {
			_string[0].xpos = a->x - camera._cur.x + (_screenWidth / 2);

			if (VAR(VAR_V5_TALK_STRING_Y) < 0) {
				s = (a->scaley * (int)VAR(VAR_V5_TALK_STRING_Y)) / 0xFF;
				_string[0].ypos = ((VAR(VAR_V5_TALK_STRING_Y) - s) >> 1) + s - a->elevation + a->y;
			} else {
				_string[0].ypos = (int)VAR(VAR_V5_TALK_STRING_Y);
			}

		} else {
			s = a->scaley * a->talkPosY / 0xFF;
			_string[0].ypos = ((a->talkPosY - s) >> 1) + s - a->elevation + a->y;

			if (_string[0].ypos < camera._cur.y - (_screenHeight / 2))
				_string[0].ypos = camera._cur.y - (_screenHeight / 2);

			s = a->scalex * a->talkPosX / 0xFF;
			_string[0].xpos = ((a->talkPosX - s) >> 1) + s + a->x - camera._cur.x + (_screenWidth / 2);
		}

		if (_string[0].ypos < 1)
			_string[0].ypos = 1;

		if (_string[0].xpos < 80)
			_string[0].xpos = 80;
		if (_string[0].xpos > _screenWidth - 80)
			_string[0].xpos = _screenWidth - 80;
	}

	_charset->_top = _string[0].ypos;
	_charset->_startLeft = _charset->_left = _string[0].xpos;

	if (a && a->charset)
		_charset->setCurID(a->charset);
	else
		_charset->setCurID(_string[0].charset);

	_charset->_center = _string[0].center;
	_charset->_right = _string[0].right;
	_charset->setColor(_charsetColor);

	if (!(_features & GF_AFTER_V2 || _features & GF_AFTER_V3))	// FIXME
		for (i = 0; i < 4; i++)
			_charsetColorMap[i] = _charsetData[_charset->getCurID()][i];

	if (_keepText) {
		_charset->_str = gdi._mask;
	}

	if (_talkDelay)
		return;

	if (_haveMsg != 0xFF && _haveMsg != 0xFE) {
		// FIXME: DIG and CMI never set sfxMode or any actor talk data...
		// This hack will force the backup cutoff system to be used instead,
		// unless the talkChannel is null (eg, this string has no sound attached)
		if ((_gameId == GID_CMI || _gameId == GID_DIG) && (_sound->_talkChannel > 0))
			return;

		if (_sound->_sfxMode == 0)
			stopTalk();
		return;
	}

	if (a && !_string[0].no_talk_anim) {
		has_anim = true;
		_useTalkAnims = true;
	}

	// HACK: Most of the audio sync in Loom is handled by the "MI1
	// timer", but some of it depends on text strings timing out at
	// the right moment.

	if (_gameId == GID_LOOM256) {
		_defaultTalkDelay = 100;
		VAR(VAR_CHARINC) = 5;
	}

	_talkDelay = _defaultTalkDelay;

	if (!_keepText) {
		if ((_features & GF_AFTER_V2 || _features & GF_AFTER_V3) && _gameId != GID_LOOM) {
			_charset->_hasMask = true;
			gdi._mask.left = _string[0].xpos;
			gdi._mask.top = _string[0].ypos;
			gdi._mask.bottom = _string[0].ypos + 8;
			gdi._mask.right = _screenWidth;
			if (_string[0].ypos <= 16)	// If we are cleaning the text line, clean 2 lines.
				gdi._mask.bottom = 16;
		}
		restoreCharsetBg();
	}

	t = _charset->_right - _string[0].xpos - 1;
	if (_charset->_center) {
		if (t > _charset->_nextLeft)
			t = _charset->_nextLeft;
		t <<= 1;
	}

	buffer = _charsetBuffer + _charsetBufPos;
	if (!(_features & GF_AFTER_V2 || _features & GF_AFTER_V3))
		_charset->addLinebreaks(0, buffer, 0, t);

	if (_charset->_center) {
		_charset->_nextLeft -= _charset->getStringWidth(0, buffer) >> 1;
		if (_charset->_nextLeft < 0)
			_charset->_nextLeft = 0;
	}

	_charset->_disableOffsX = _charset->_firstChar = !_keepText;

	do {
		c = *buffer++;
		if (c == 0) {
			// End of text reached, set _haveMsg to 1 so that the text will be
			// removed next time CHARSET_1 is called.
			_haveMsg = 1;
			_keepText = false;
			break;
		}
		if (c == 13) {
		newLine:;
			_charset->_nextLeft = _string[0].xpos;
			if (_charset->_center) {
				_charset->_nextLeft -= _charset->getStringWidth(0, buffer) >> 1;
			}
			_charset->_nextTop += _charset->getFontHeight();
			if (!(_features & GF_AFTER_V2 || _features & GF_AFTER_V3)) {
				// FIXME - is this really needed?
				_charset->_disableOffsX = true;
			}
			continue;
		}

		if (c == 0xFE)
			c = 0xFF;

		if (c != 0xFF) {
			_charset->_left = _charset->_nextLeft;
			_charset->_top = _charset->_nextTop;
			if(c & 0x80 && _CJKMode)
				c += *buffer++ * 256;
			if (_features & GF_AFTER_V2 || _features & GF_AFTER_V3) {
				_charset->printChar(c);
			} else if (_features & GF_AFTER_V6) {
				if (!_noSubtitles || (_haveMsg != 0xFE && _haveMsg != 0xFF))
					_charset->printChar(c);
			} else {
				if (!_noSubtitles || _haveMsg != 0xFE)
					_charset->printChar(c);
			}

			_charset->_nextLeft = _charset->_left;
			_charset->_nextTop = _charset->_top;
			if (_features & GF_AFTER_V2) {
				_talkDelay += _defaultTalkDelay / 20;
				VAR(VAR_CHARCOUNT)++;
			} else
				_talkDelay += (int)VAR(VAR_CHARINC);
			continue;
		}

		c = *buffer++;
		switch(c) {
		case 1:
			goto newLine;
		case 2:
			_haveMsg = 0;
			_keepText = true;
			break;
		case 3:		
			if (_haveMsg != 0xFE)
				_haveMsg = 0xFF;
			_keepText = false;
			break;		
		case 9:
			frme = *buffer++;
			frme |= *buffer++ << 8;
			has_anim = true;
			break;
		case 10:
			talk_sound_a = buffer[0] | (buffer[1] << 8) | (buffer[4] << 16) | (buffer[5] << 24);
			talk_sound_b = buffer[8] | (buffer[9] << 8) | (buffer[12] << 16) | (buffer[13] << 24);
			has_talk_sound = true;
			buffer += 14;

			// Set flag that speech variant exist of this msg
			if (_haveMsg == 0xFF)
				_haveMsg = 0xFE;
			break;		
		case 12:
			int color;
			color = *buffer++;
			color |= *buffer++ << 8;
			if (color == 0xFF)
				_charset->setColor(_charsetColor);
			else
				_charset->setColor(color);
			break;
		case 13:
			buffer += 2;
			break;
		case 14: {
			int oldy = _charset->getFontHeight();

			_charset->setCurID(*buffer++);
			buffer += 2;
			for (i = 0; i < 4; i++)
				_charsetColorMap[i] = _charsetData[_charset->getCurID()][i];
			_charset->_nextTop -= _charset->getFontHeight() - oldy;
			break;
			}
		default:
			warning("CHARSET_1: invalid code %d", c);
		}
		if (c == 3 || c == 2)
			break;

	} while (1);

	// Even if talkSound() is called, we may still have to call
	// startAnimActor() since actorTalk() may already have caused the
	// wrong animation frame to be drawn, and the talkSound() won't be
	// processed until after the next screen update. Bleah.

	if (has_talk_sound)
		_sound->talkSound(talk_sound_a, talk_sound_b, 2, frme);
	if (a && has_anim)
		a->startAnimActor(frme != -1 ? frme : a->talkStartFrame);

	_charsetBufPos = buffer - _charsetBuffer;

	_charset->_hasMask = (_charset->_str.left != -1);
	gdi._mask = _charset->_str;
}

void Scumm::drawString(int a) {
	byte buf[256];
	byte *space;
	int i, c;
	byte fontHeight = 0;
	uint color;

	_msgPtrToAdd = buf;
	_messagePtr = addMessageToStack(_messagePtr);

	_charset->_top = _string[a].ypos;
	_charset->_startLeft = _charset->_left = _string[a].xpos;
	_charset->_right = _string[a].right;
	_charset->_center = _string[a].center;
	_charset->setColor(_string[a].color);
	_charset->_disableOffsX = _charset->_firstChar = true;
	_charset->setCurID(_string[a].charset);

	if (!(_features & GF_AFTER_V2 || _features & GF_AFTER_V3)) {
		for (i = 0; i < 4; i++)
			_charsetColorMap[i] = _charsetData[_charset->getCurID()][i];
	}

	fontHeight = _charset->getFontHeight();

	_msgPtrToAdd = buf;

	// trim from the right
	space = NULL;
	while (*_msgPtrToAdd) {
		if (*_msgPtrToAdd == ' ') {
			if (!space)
				space = _msgPtrToAdd;
		} else {
			space = NULL;
		}
		_msgPtrToAdd++;
	}
	if (space)
		*space = '\0';
	if (_charset->_center) {
		_charset->_left -= _charset->getStringWidth(a, buf) >> 1;
	}

	if (!(_features & GF_AFTER_V7))
		_charset->_ignoreCharsetMask = true;


	// In Full Throttle (and other games?), verb text should always mask
	// and never time out. We can't do it blindly for all games, because
	// it causes problem with the FOA intro.

	if (_gameId == GID_FT && a == 4)
		_talkDelay = -1;

	if (!buf[0]) {
		buf[0] = ' ';
		buf[1] = 0;
	}

	for (i = 0; (c = buf[i++]) != 0;) {
		if (c == 0xFE || c == 0xFF) {
			c = buf[i++];
			switch (c) {
			case 9:
			case 10:
			case 13:
			case 14:
				i += 2;
				break;
			case 1:
			case 8:
				if (_charset->_center) {
					_charset->_left = _charset->_startLeft - _charset->getStringWidth(a, buf + i);
				} else {
					_charset->_left = _charset->_startLeft;
				}
				_charset->_top += fontHeight;
				break;
			case 12:
				color = buf[i] + (buf[i + 1] << 8);
				i += 2;
				if (color == 0xFF)
					_charset->setColor(_string[a].color);
				else
					_charset->setColor(color);
				break;
			}
		} else {
			if (a == 1 && (_features & GF_AFTER_V6)) {
				if (_string[a].no_talk_anim == 0)
					_charset->_blitAlso = true;
			}
			if(c >= 0x80 && _CJKMode)
				c += buf[i++] * 256;
			_charset->printChar(c);
			_charset->_blitAlso = false;
		}
	}

	_charset->_ignoreCharsetMask = false;

	if (a == 0) {
		_charset->_nextLeft = _charset->_left;
		_charset->_nextTop = _charset->_top;
	} 


	_string[a].xpos = _charset->_str.right + 8;	// Indy3: Fixes Grail Diary text positioning

	if (_features & GF_AFTER_V7) {
		_charset->_hasMask = true;
		gdi._mask.extend(_charset->_str);
	}
}

const byte *Scumm::addMessageToStack(const byte *msg) {
	int num, numorg;
	unsigned char *ptr, chr;

	numorg = num = _numInMsgStack;
	ptr = getResourceAddress(rtTemp, 6);

	if (ptr == NULL)
		error("Message stack not allocated");

	if (msg == NULL) {
		warning("Bad message in addMessageToStack, ignoring");
		return NULL;
	}

	while ((ptr[num++] = chr = *msg++) != 0) {
		if (num >= 500)
			error("Message stack overflow");

		if (chr == 0xff) {	// 0xff is an escape character			
			ptr[num++] = chr = *msg++;	// followed by a "command" code 
			if (chr != 1 && chr != 2 && chr != 3 && chr != 8) {
				ptr[num++] = *msg++;	// and some commands are followed by parameters to the functions below
				ptr[num++] = *msg++;	// these are numbers of names, strings, verbs, variables, etc
				if (_features & GF_AFTER_V8) {
					ptr[num++] = *msg++;
					ptr[num++] = *msg++;
				}
			}
		}
	}

	_numInMsgStack = num;
	num = numorg;

	while (1) {
		ptr = getResourceAddress(rtTemp, 6);
		chr = ptr[num++];
		if (chr == 0)
			break;
		if (chr == 0xFF) {
			chr = ptr[num++];
			switch (chr) {
			case 4:
				if (_features & GF_AFTER_V8) {
					addIntToStack(READ_LE_UINT32(ptr + num));
					num += 4;
				} else {
					addIntToStack(READ_LE_UINT16(ptr + num));
					num += 2;
				}
				break;
			case 5:
				if (_features & GF_AFTER_V8) {
					addVerbToStack(READ_LE_UINT32(ptr + num));
					num += 4;
				} else {
					addVerbToStack(READ_LE_UINT16(ptr + num));
					num += 2;
				}
				break;
			case 6:
				if (_features & GF_AFTER_V8) {
					addNameToStack(READ_LE_UINT32(ptr + num));
					num += 4;
				} else {
					addNameToStack(READ_LE_UINT16(ptr + num));
					num += 2;
				}
				break;
			case 7:
				if (_features & GF_AFTER_V8) {
					addStringToStack(READ_LE_UINT32(ptr + num));
					num += 4;
				} else if (_features & GF_AFTER_V2) {
					int var = READ_LE_UINT16(ptr + num);
					num += 2;
					char c;
					while ((c = (char) _scummVars[var++])) {
						if (c != '@')
							*_msgPtrToAdd++ = c;
					}
				} else {
					addStringToStack(READ_LE_UINT16(ptr + num));
					num += 2;
				}
				break;
			case 3:
			case 9:
//#if defined(DOTT)
			case 10:
			case 12:
			case 13:
			case 14:
//#endif
				*_msgPtrToAdd++ = 0xFF;
				*_msgPtrToAdd++ = chr;
				*_msgPtrToAdd++ = ptr[num++];
				*_msgPtrToAdd++ = ptr[num++];
				if (_features & GF_AFTER_V8) {
					// FIXME - is this right?!?
					*_msgPtrToAdd++ = ptr[num++];
					*_msgPtrToAdd++ = ptr[num++];
				}
				break;
			default: 
				debug(2, "addMessageToStack(): string escape sequence %d unknown", chr);
				*_msgPtrToAdd++ = 0xFF;
				*_msgPtrToAdd++ = chr;
				break;
			}
		} else {
			if (chr != '@') {
				*_msgPtrToAdd++ = chr;
			}
		}
	}
	*_msgPtrToAdd = 0;
	_numInMsgStack = numorg;

	return msg;
}

void Scumm::addIntToStack(int var) {
	int num;

	num = readVar(var);
	_msgPtrToAdd += sprintf((char *)_msgPtrToAdd, "%d", num);
}

void Scumm::addVerbToStack(int var)
{
	int num, k;

	num = readVar(var);
	if (num) {
		for (k = 1; k < _maxVerbs; k++) {
			if (num == _verbs[k].verbid && !_verbs[k].type && !_verbs[k].saveid) {
				byte *ptr = getResourceAddress(rtVerb, k);
				if ((_features & GF_AFTER_V8) && (ptr[0] == '/')) {
					char pointer[20];
					int i, j;

					translateText(ptr, _transText);

					for (i = 0, j = 0; (ptr[i] != '/' || j == 0) && j < 19; i++) {
							if (ptr[i] != '/')
							pointer[j++] = ptr[i];
					}
					pointer[j] = 0;
					_sound->_talkChannel = _sound->playBundleSound(pointer);
					addMessageToStack(_transText);
				} else {
					addMessageToStack(ptr);
				}
				break;
			}
		}
	} else {
		addMessageToStack((const byte *)"");
	}
}

void Scumm::addNameToStack(int var)
{
	int num;
	const byte *ptr = 0;

	num = readVar(var);
	if (num)
		ptr = getObjOrActorName(num);
	if (ptr) {
		if ((_features & GF_AFTER_V8) && (ptr[0] == '/')) {
			char pointer[20];
			int i, j;

			translateText(ptr, _transText);
			for (i = 0, j = 0; (ptr[i] != '/' || j == 0) && j < 19; i++) {
				if (ptr[i] != '/')
					pointer[j++] = ptr[i];
			}
			pointer[j] = 0;

			addMessageToStack(_transText);
		} else {
			addMessageToStack(ptr);
		}
	} else {
		addMessageToStack((const byte *)"");
	}
}

void Scumm::addStringToStack(int var) {
	byte *ptr;

	if (_features & GF_AFTER_V6 || _gameId == GID_INDY3_256)
		var = readVar(var);

	if (var) {
		ptr = getStringAddress(var);
		if (ptr) {
			if ((_features & GF_AFTER_V8) && (ptr[0] == '/')) {
				char pointer[20];
				int i, j;

				translateText(ptr, _transText);

				for (i = 0, j = 0; (ptr[i] != '/' || j == 0) && j < 19; i++) {
						if (ptr[i] != '/')
								pointer[j++] = ptr[i];
				}
				pointer[j] = 0;

				addMessageToStack(_transText);
			} else {
				addMessageToStack(ptr);
			}
		}
	} else
		addMessageToStack((const byte *)"");
}

void Scumm::initCharset(int charsetno) {
	int i;

	if (!getResourceAddress(rtCharset, charsetno))
		loadCharset(charsetno);

	_string[0].t_charset = charsetno;
	_string[1].t_charset = charsetno;

	for (i = 0; i < 16; i++)
		_charsetColorMap[i] = _charsetData[_charset->getCurID()][i];
}

void Scumm::enqueueText(const byte *text, int x, int y, byte color, byte charset, bool center) {
	BlastText &bt = _blastTextQueue[_blastTextQueuePos++];
	assert(_blastTextQueuePos <= 32);
	
	strcpy((char *)bt.text, (const char *)text);
	bt.xpos = x;
	bt.ypos = y;
	bt.color = color;
	bt.charset = charset;
	bt.center = center;
}

void Scumm::drawBlastTexts() {
	// FIXME

	byte *buf;
	int c;
	int i;

	_charset->_ignoreCharsetMask = true;
	for (i = 0; i < _blastTextQueuePos; i++) {

		buf = _blastTextQueue[i].text;

		_charset->_top = _blastTextQueue[i].ypos;
		_charset->_startLeft = _charset->_left = _blastTextQueue[i].xpos;
		_charset->_right = _screenWidth - 1;
		_charset->_center = _blastTextQueue[i].center;
		_charset->setColor(_blastTextQueue[i].color);
		_charset->_disableOffsX = _charset->_firstChar = true;
		_charset->setCurID(_blastTextQueue[i].charset);
		_charset->_nextLeft = _blastTextQueue[i].xpos;
		_charset->_nextTop = _blastTextQueue[i].ypos;

		// Center text if necessary
		if (_charset->_center) {
			_charset->_nextLeft -= _charset->getStringWidth(0, buf) >> 1;
			if (_charset->_nextLeft < 0)
				_charset->_nextLeft = 0;
		}

		do {
			c = *buf++;
			if (c != 0 && c != 0xFF) {
				_charset->_left = _charset->_nextLeft;
				_charset->_top = _charset->_nextTop;
 				if(c >= 0x80 && _CJKMode)
 					c += *buf++ * 256;
				_charset->printChar(c);
				_charset->_nextLeft = _charset->_left;
				_charset->_nextTop = _charset->_top;
			}
		} while (c);

		_blastTextQueue[i].rect = _charset->_str;
	}
	_charset->_ignoreCharsetMask = false;
}

void Scumm::removeBlastTexts() {
	int i;

	for (i = 0; i < _blastTextQueuePos; i++) {
		restoreBG(_blastTextQueue[i].rect);
	}
	_blastTextQueuePos = 0;
}

int indexCompare(const void *p1, const void *p2) {
	const LangIndexNode *i1 = (const LangIndexNode *) p1;
	const LangIndexNode *i2 = (const LangIndexNode *) p2;

	return strcmp(i1->tag, i2->tag);
}

void Scumm::loadLanguageBundle() {
	File file;
	int32 size;

	if (_gameId == GID_DIG) {
		file.open("language.bnd", getGameDataPath());
	} else if (_gameId == GID_CMI) {
		file.open("language.tab", getGameDataPath());
	} else {
		return;
	}
	if(file.isOpen() == false) {
		_existLanguageFile = false;
		return;
	}
	
	_existLanguageFile = true;

	size = file.size();
	_languageBuffer = (char *)calloc(1, size+1);
	file.read(_languageBuffer, size);
	file.close();

	// Create an index of the language file.
	// FIXME: Extend this mechanism to also cover The Dig?

	int32 i;
	char *ptr = _languageBuffer;

	// Count the number of lines in the language file.

	_languageIndexSize = 0;

	for (;;) {
		ptr = strpbrk(ptr, "\n\r");
		if (ptr == NULL)
			break;
		while (*ptr == '\n' || *ptr == '\r')
			ptr++;
		_languageIndexSize++;
	}

	// Fill the language file index. This is just an array of
	// tags and offsets. I did consider using a balanced tree
	// instead, but the extra overhead in the node structure would
	// easily have doubled the memory consumption of the index.

	_languageIndex = (LangIndexNode *)calloc(_languageIndexSize, sizeof(LangIndexNode));

	ptr = _languageBuffer;

	if (_gameId == GID_DIG) {
		int lineCount = _languageIndexSize;
		const char *baseTag = "";
		byte enc = 0;	// Initially assume the language file is not encoded
		
		// We'll determine the real index size as we go.
		_languageIndexSize = 0;
		for (i = 0; i < lineCount; i++) {
			if (*ptr == '!') {
				// Don't know what a line with '!' means, just ignore it
			} else if (*ptr == 'e') {
				// File is encoded!
				enc = 0x13;
			} else if (*ptr == '@') {
				// A new 'base tag'
				baseTag = ptr + 1;
			} else if (*ptr == '#') {
				// Number of subtags following a given basetag. We don't need that
				// information so we just skip it
			} else if (isdigit(*ptr)) {
				int idx = 0;
				// A number (up to three digits)...
				while (isdigit(*ptr)) {
					idx = idx * 10 + (*ptr - '0');
					ptr++;
				}
				
				// ...followed by a slash...
				assert(*ptr == '/');
				ptr++;
				
				// ...and then the translated message, possibly encoded
				_languageIndex[_languageIndexSize].offset = ptr - _languageBuffer;
				
				// Decode string if necessary.
				if (enc) {
					while (*ptr != '\n' && *ptr != '\r')
						*ptr++ ^= enc;
				}
				
				// The tag is the basetag, followed by a dot and then the index
				sprintf(_languageIndex[_languageIndexSize].tag, "%s.%03d", baseTag, idx);
				
				// That was another index entry
				_languageIndexSize++;
			}

			// Skip over newlines (and turn them into null bytes)
			ptr = strpbrk(ptr, "\n\r");
			if (ptr == NULL)
				break;
			while (*ptr == '\n' || *ptr == '\r')
				*ptr++ = 0;
		}
	} else {
		for (i = 0; i < _languageIndexSize; i++) {
			// First 8 chars in the line give the string ID / 'tag'
			int j;
			for (j = 0; j < 8 && !isspace(*ptr); j++, ptr++)
				_languageIndex[i].tag[j] = toupper(*ptr);
			_languageIndex[i].tag[j] = 0;
	
			// After that follows a single space which we skip
			assert(isspace(*ptr));
			ptr++;
			
			// Then comes the translated string: we record an offset to that.
			_languageIndex[i].offset = ptr - _languageBuffer;
	
			// Skip over newlines (and turn them into null bytes)
			ptr = strpbrk(ptr, "\n\r");
			if (ptr == NULL)
				break;
			while (*ptr == '\n' || *ptr == '\r')
				*ptr++ = 0;
		}
	}

	// Sort the index nodes. We'll later use bsearch on it, which is just as efficient
	// as using a binary tree, speed wise.
	qsort(_languageIndex, _languageIndexSize, sizeof(LangIndexNode), indexCompare);
}

void Scumm::translateText(const byte *text, byte *trans_buff) {
	int l;
	
	if ((text[0] == '/') && _existLanguageFile) {
		LangIndexNode target;
		LangIndexNode *found = NULL;

		// copy name from text /..../
		for (l = 0; (l < 12) && (text[l + 1] != '/'); l++)
			target.tag[l] = toupper(text[l + 1]);
		target.tag[l] = 0;

		// HACK: These are used for the object line when
		// using one object on another. I don't know if the
		// text in the language file is a placeholder or if
		// we're supposed to use it, but at least in the
		// English version things will work so much better if
		// we can't find translations for these.

		if (strcmp(target.tag, "PU_M001") != 0 && strcmp(target.tag, "PU_M002") != 0)
			found = (LangIndexNode *)bsearch(&target, _languageIndex, _languageIndexSize, sizeof(LangIndexNode), indexCompare);
		if (found != NULL) {
			strcpy((char *)trans_buff, _languageBuffer + found->offset);
			return;
		}
	}
	
	byte *pointer = (byte *)strchr((const char *)text + 1, '/');
	if (pointer != NULL) {
		pointer++;
		if (_gameId == GID_CMI) {
			memcpy(trans_buff, pointer, resStrLen(pointer) + 1);
		} else if (_gameId == GID_DIG) {
			l = 0;
			while (*pointer != '/' && *pointer != 0xff && *pointer != 0) {
				trans_buff[l++] = *pointer++;
			}
			trans_buff[l] = '\0';
		}
	} else {
		memcpy(trans_buff, text, resStrLen(text) + 1);
	}
}