CHEWY: Add support for encrypted text resources

These are mainly used for error messages

engines/chewy/console.cpp

@@ -37,6 +37,7 @@ Console::Console(ChewyEngine *vm) : GUI::Debugger(), _vm(vm) {
 	registerCmd("play_sound",	WRAP_METHOD(Console, Cmd_PlaySound));
 	registerCmd("play_speech",	WRAP_METHOD(Console, Cmd_PlaySpeech));
 	registerCmd("play_music",	WRAP_METHOD(Console, Cmd_PlayMusic));
+	registerCmd("text",			WRAP_METHOD(Console, Cmd_Text));
 }
 
 Console::~Console() {
@@ -148,4 +149,21 @@ bool Console::Cmd_PlayMusic(int argc, const char **argv) {
 	return true;
 }
 
+bool Console::Cmd_Text(int argc, const char **argv) {
+	if (argc < 2) {
+		debugPrintf("Usage: <file> <text number>\n");
+		return true;
+	}
+
+	Common::String filename = argv[1];
+	int resNum = atoi(argv[2]);
+
+	TextResource *res = new TextResource(filename);
+	Common::String str = res->getText(resNum);
+	this->debugPrintf("Text: %s\n", str.c_str());
+	delete res;
+
+	return true;
+}
+
 } // End of namespace Chewy

engines/chewy/console.h

@@ -43,6 +43,7 @@ private:
 	bool Cmd_PlaySound(int argc, const char **argv);
 	bool Cmd_PlaySpeech(int argc, const char **argv);
 	bool Cmd_PlayMusic(int argc, const char **argv);
+	bool Cmd_Text(int argc, const char **argv);
 };
 
 } // End of namespace Chewy

engines/chewy/resource.cpp

@@ -30,17 +30,37 @@
 namespace Chewy {
 
 Resource::Resource(Common::String filename) {
+	const uint32 headerGeneric = MKTAG('N', 'G', 'S', '\0');
+	const uint32 headerTxtDec  = MKTAG('T', 'C', 'F', '\0');
+	const uint32 headerTxtEnc  = MKTAG('T', 'C', 'F', '\1');
+
 	_stream.open(filename);
-	uint32 magicBytes = MKTAG('N', 'G', 'S', '\0');
-	if (_stream.readUint32BE() != magicBytes)
+
+	uint32 header = _stream.readUint32BE();
+	bool isText = header == headerTxtDec || header == headerTxtEnc;
+
+	if (header != headerGeneric && !isText)
 		error("Invalid resource - %s", filename.c_str());
-	_resType = (ResourceType)_stream.readUint16LE();
+
+	if (isText) {
+		_resType = kResourceTCF;
+		_encrypted = (header == headerTxtEnc);
+	} else {
+		_resType = (ResourceType)_stream.readUint16LE();
+		_encrypted = false;
+	}
+
 	_chunkCount = _stream.readUint16LE();
 
 	for (uint i = 0; i < _chunkCount; i++) {
 		Chunk cur;
 		cur.size = _stream.readUint32LE();
-		cur.type = (ResourceType)_stream.readUint16LE();
+
+		if (!isText)
+			cur.type = (ResourceType)_stream.readUint16LE();
+		else
+			cur.num = _stream.readUint16LE();
+
 		cur.pos = _stream.pos();
 
 		_stream.skip(cur.size);
@@ -57,11 +77,15 @@ uint32 Resource::getChunkCount() const {
 	return _chunkList.size();
 }
 
-Chunk *Resource::getChunk(int num) {
+Chunk *Resource::getChunk(uint num) {
+	assert(num < _chunkList.size());
+
 	return &_chunkList[num];
 }
 
-byte *Resource::getChunkData(int num) {
+byte *Resource::getChunkData(uint num) {
+	assert(num < _chunkList.size());
+
 	Chunk *chunk = &_chunkList[num];
 	byte *data = new byte[chunk->size];
 
@@ -71,7 +95,9 @@ byte *Resource::getChunkData(int num) {
 	return data;
 }
 
-TBFChunk *BackgroundResource::getImage(int num) {
+TBFChunk *BackgroundResource::getImage(uint num) {
+	assert(num < _chunkList.size());
+
 	Chunk *chunk = &_chunkList[num];
 	TBFChunk *tbf = new TBFChunk();
 
@@ -111,7 +137,9 @@ TBFChunk *BackgroundResource::getImage(int num) {
 	return tbf;
 }
 
-SoundChunk *SoundResource::getSound(int num) {
+SoundChunk *SoundResource::getSound(uint num) {
+	assert(num < _chunkList.size());
+
 	Chunk *chunk = &_chunkList[num];
 	SoundChunk *sound = new SoundChunk();
 
@@ -155,4 +183,30 @@ SoundChunk *SoundResource::getSound(int num) {
 	return sound;
 }
 
+Common::String TextResource::getText(uint num) {
+	assert(num < _chunkList.size());
+
+	Chunk *chunk = &_chunkList[num];
+	Common::String str;
+	byte *data = new byte[chunk->size];
+
+	_stream.seek(chunk->pos, SEEK_SET);
+
+	_stream.read(data, chunk->size);
+
+	if (_encrypted) {
+		byte *c = data;
+
+		for (uint i = 0; i < chunk->size; i++) {
+			*c = -(*c);
+			++c;
+		}
+	}
+
+	str = (char *)data;
+	delete[] data;
+
+	return str;
+}
+
 } // End of namespace Chewy

engines/chewy/resource.h

@@ -70,6 +70,7 @@ enum ResourceType {
 // Generic chunk header
 struct Chunk {
 	uint32 size;
+	uint16 num;	// same as the type below, used in chunks where the type is substituted with count
 	ResourceType type;
 	uint32 pos;	// position of the actual data
 };
@@ -103,13 +104,14 @@ public:
 
 	ResourceType getType() const { return _resType; }
 	uint32 getChunkCount() const;
-	Chunk *getChunk(int num);
-	virtual byte *getChunkData(int num);
+	Chunk *getChunk(uint num);
+	virtual byte *getChunkData(uint num);
 
 protected:
 	Common::File _stream;
 	uint16 _chunkCount;
 	ResourceType _resType;
+	byte _encrypted;
 
 	ChunkList _chunkList;
 };
@@ -119,7 +121,7 @@ public:
 	BackgroundResource(Common::String filename) : Resource(filename) {}
 	~BackgroundResource() {}
 
-	TBFChunk *getImage(int num);
+	TBFChunk *getImage(uint num);
 };
 
 class SoundResource : public Resource {
@@ -127,7 +129,15 @@ public:
 	SoundResource(Common::String filename) : Resource(filename) {}
 	~SoundResource() {}
 
-	SoundChunk *getSound(int num);
+	SoundChunk *getSound(uint num);
+};
+
+class TextResource : public Resource {
+public:
+	TextResource(Common::String filename) : Resource(filename) {}
+	~TextResource() {}
+
+	Common::String getText(uint num);
 };
 
 } // End of namespace Chewy