SCUMM: Add missing Lemonhead lines in English CD Monkey Island 1

Apparently these were lost when the game was converted from floppy to CD
version. Not just in the English version, but that's all I have. We
should come up with a way to make it easy to add other languages,
though.

engines/scumm/resource.cpp

@@ -1726,6 +1726,16 @@ void ScummEngine::applyWorkaroundIfNeeded(ResType type, int idx) {
 		delete[] patchedScript;
 	} else
 
+	// For some reason, the CD version of Monkey Island 1 removes some of
+	// the text when giving the wimpy idol to the cannibals. It looks like
+	// a mistake, because one of the text that is printed is immediately
+	// overwritten. This probably affects all CD versions, so we just have
+	// to add further patches as they are reported.
+
+	if (_game.id == GID_MONKEY && type == rtRoom && idx == 25) {
+		tryPatchMI1CannibalScript(getResourceAddress(type, idx), size);
+	} else
+
 	// There is a cracked version of Maniac Mansion v2 that attempts to
 	// remove the security door copy protection. With it, any code is
 	// accepted as long as you get the last digit wrong. Unfortunately,
@@ -1771,5 +1781,72 @@ bool ScummEngine::verifyMI2MacBootScript(byte *buf, int size) {
 	return true;
 }
 
+bool ScummEngine::tryPatchMI1CannibalScript(byte *buf, int size) {
+	assert(_game.id == GID_MONKEY);
+
+	int expectedSize = -1;
+	int scriptOffset = -1;
+	int scriptLength = -1;
+	Common::String expectedMd5;
+	int patchOffset = -1;
+	int patchLength = -1;
+
+	switch (_language) {
+	case Common::EN_ANY:
+		expectedSize = 82906;
+		scriptOffset = 73883;
+		scriptLength = 607;
+		expectedMd5 = "98b1126a836ef5bfefff10b605b20555";
+		patchOffset = 167;
+		patchLength = 126;
+		break;
+	default:
+		return false;
+	}
+
+	if (size == expectedSize) {
+		// There isn't enough space in the script for the revised
+		// texts, so these abbreviations will be expanded in
+		// decodeParseString().
+		const byte patchData[] = {
+			0x14, 0x03, 0x0F,       // print(3,[Text("/LMH.001/");
+			0x2F, 0x4C, 0x4D, 0x48,
+			0x2E, 0x30, 0x30, 0x31,
+			0x2F, 0x00,
+			0xAE, 0x02,             // WaitForMessage();
+			0x14, 0x03, 0x0F,       // print(3,[Text("/LMH.001/");
+			0x2F, 0x4C, 0x4D, 0x48,
+			0x2E, 0x30, 0x30, 0x32,
+			0x2F,			// No terminating 0x00!
+		};
+
+		byte *scriptPtr = buf + scriptOffset;
+
+		// Check that the data is a local script.
+		if (READ_BE_UINT32(scriptPtr) != MKTAG('L','S','C','R'))
+			return false;
+
+		// Check that the first instruction to be patched is o5_print
+		if (scriptPtr[patchOffset] != 0x14)
+			return false;
+
+		// Check that the MD5 sum matches a known patchable script.
+		Common::MemoryReadStream stream(buf + scriptOffset, scriptLength);
+		Common::String md5 = Common::computeStreamMD5AsString(stream);
+
+		if (md5 != expectedMd5)
+			return false;
+
+		// Pad the rest of the replaced script part with spaces before
+		// terminating the string.
+
+		memcpy(scriptPtr + patchOffset, patchData, sizeof(patchData));
+		memset(scriptPtr + patchOffset + sizeof(patchData), 32, patchLength - sizeof(patchData) - 1);
+		scriptPtr[patchOffset + patchLength - 1] = 0;
+	}
+
+	return true;
+}
+
 
 } // End of namespace Scumm

engines/scumm/script_v5.cpp

@@ -2777,6 +2777,8 @@ void ScummEngine_v5::decodeParseString() {
 					strcpy(tmpBuf + diff, "5000");
 					strcpy(tmpBuf + diff + 4, tmp + sizeof("NCREDIT-NOTE-AMOUNT") - 1);
 					printString(textSlot, (byte *)tmpBuf);
+				} if (_game.id == GID_MONKEY && _roomResource == 25 && vm.slot[_currentScript].number == 205) {
+					printPatchedMI1CannibalString(textSlot, _scriptPointer);
 				} else {
 					printString(textSlot, _scriptPointer);
 				}
@@ -2810,4 +2812,26 @@ void ScummEngine_v5::decodeParseString() {
 	_string[textSlot].saveDefault();
 }
 
+void ScummEngine_v5::printPatchedMI1CannibalString(int textSlot, const byte *ptr) {
+	const char *msg = (const char *)ptr;
+
+#define MSG_WAIT "\xFF\x03"
+
+	if (strncmp((const char *)ptr, "/LMH.001/", 9) == 0) {
+		msg =
+"Oooh, that's nice." MSG_WAIT
+"Simple.  Just like one of mine." MSG_WAIT
+"And little.  Like mine.";
+	} else if (strncmp((const char *)ptr, "/LMH.002/", 9) == 0) {
+		msg =
+"And it says, `Made by Lemonhead`^" MSG_WAIT
+"^just like one of mine!" MSG_WAIT
+"We should take this to the Great Monkey.";
+	}
+
+#undef MSG_WAIT
+
+	printString(textSlot, (const byte *)msg);
+}
+
 } // End of namespace Scumm

engines/scumm/scumm.h

@@ -701,6 +701,8 @@ public:
 	void applyWorkaroundIfNeeded(ResType type, int idx);
 	bool verifyMI2MacBootScript();
 	bool verifyMI2MacBootScript(byte *buf, int size);
+	bool tryPatchMI1CannibalScript(byte *buf, int size);
+
 	int getResourceDataSize(const byte *ptr) const;
 	void dumpResource(const char *tag, int index, const byte *ptr, int length = -1);
 

engines/scumm/scumm_v5.h

@@ -65,6 +65,7 @@ protected:
 	void setupScummVars() override;
 	void resetScummVars() override;
 	virtual void decodeParseString();
+	void printPatchedMI1CannibalString(int textSlot, const byte *ptr);
 
 	void saveLoadWithSerializer(Common::Serializer &s) override;