MUTATIONOFJB: Implement RANDOM command.

3 files changed, 181 insertions, 1 deletions

diff --git a/engines/mutationofjb/commands/endblockcommand.cpp b/engines/mutationofjb/commands/endblockcommand.cpp
index 3b4c25bf51..5fcccd390b 100644
--- a/engines/mutationofjb/commands/endblockcommand.cpp
+++ b/engines/mutationofjb/commands/endblockcommand.cpp
@@ -56,7 +56,7 @@ bool EndBlockCommandParser::parse(const Common::String &line, ScriptParseContext
 	}
 
 	const char firstChar = line.firstChar();
-	if (firstChar != '#' && firstChar != '=' && firstChar != '-') {
+	if (firstChar != '#' && firstChar != '=' && firstChar != '-' && firstChar != '\\') {
 		return false;
 	}
 
diff --git a/engines/mutationofjb/commands/randomcommand.cpp b/engines/mutationofjb/commands/randomcommand.cpp
new file mode 100644
index 0000000000..ff03e96cc6
--- /dev/null
+++ b/engines/mutationofjb/commands/randomcommand.cpp
@@ -0,0 +1,110 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#include "mutationofjb/commands/randomcommand.h"
+
+#include "mutationofjb/game.h"
+#include "mutationofjb/script.h"
+#include "common/debug.h"
+#include "common/random.h"
+#include "common/translation.h"
+
+/*
+	"RANDOM " <numChoices>
+
+	RANDOM command randomly picks one of the command blocks that
+	follow it and jumps to its start.
+
+	These blocks start with "/" and end with "\". The end of a random
+	block also ends the current section. The number of blocks must
+	match numChoices.
+*/
+
+namespace MutationOfJB {
+
+bool RandomCommandParser::parse(const Common::String &line, ScriptParseContext &parseCtx, Command *&command) {
+	if (line.size() < 8 || !line.hasPrefix("RANDOM")) {
+		return false;
+	}
+
+	int numChoices = atoi(line.c_str() + 7);
+	if (parseCtx._pendingRandomCommand) {
+		// Nested RANDOM commands are unused and not properly supported by the original game.
+		warning(_("Ignoring nested RANDOM command."));
+	} else if (numChoices >= 1) {
+		RandomCommand *randomCommand = new RandomCommand(static_cast<uint>(numChoices));
+		parseCtx._pendingRandomCommand = randomCommand;
+		command = randomCommand;
+	} else {
+		warning(_("Ignoring malformed RANDOM command with %d choices."), numChoices);
+	}
+
+	return true;
+}
+
+bool RandomBlockStartParser::parse(const Common::String &line, ScriptParseContext &parseCtx, Command *&) {
+	if (line != "/") {
+		return false;
+	}
+
+	if (!parseCtx._pendingRandomCommand) {
+		warning(_("Unexpected start of RANDOM block"));
+	}
+
+	return true;
+}
+
+void RandomBlockStartParser::transition(ScriptParseContext &parseCtx, Command *, Command *newCommand, CommandParser *) {
+	if (newCommand && parseCtx._pendingRandomCommand) {
+		parseCtx._pendingRandomCommand->_choices.push_back(newCommand);
+	}
+}
+
+RandomCommand::RandomCommand(uint numChoices)
+	: _numChoices(numChoices),
+	  _chosenNext(nullptr)
+{
+	_choices.reserve(numChoices);
+}
+
+Command::ExecuteResult RandomCommand::execute(ScriptExecutionContext &scriptExecCtx) {
+	assert(!_choices.empty());
+
+	Common::RandomSource &rng = scriptExecCtx.getGame().getRandomSource();
+	uint choice = rng.getRandomNumber(_choices.size() - 1);
+	_chosenNext = _choices[choice];
+	return Finished;
+}
+
+Command *RandomCommand::next() const {
+	return _chosenNext;
+}
+
+Common::String RandomCommand::debugString() const {
+	return Common::String::format("RANDOM %u", _numChoices);
+}
+
+const RandomCommand::Choices &RandomCommand::getChoices() const {
+	return _choices;
+}
+
+}
diff --git a/engines/mutationofjb/commands/randomcommand.h b/engines/mutationofjb/commands/randomcommand.h
new file mode 100644
index 0000000000..ffe9fc2374
--- /dev/null
+++ b/engines/mutationofjb/commands/randomcommand.h
@@ -0,0 +1,70 @@
+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef MUTATIONOFJB_RANDOMCOMMAND_H
+#define MUTATIONOFJB_RANDOMCOMMAND_H
+
+#include "mutationofjb/commands/command.h"
+#include "common/array.h"
+#include "common/scummsys.h"
+
+namespace MutationOfJB {
+
+class RandomCommandParser : public CommandParser {
+public:
+	RandomCommandParser() {}
+
+	virtual bool parse(const Common::String &line, ScriptParseContext &parseCtx, Command *&command) override;
+};
+
+class RandomBlockStartParser : public CommandParser {
+public:
+	RandomBlockStartParser() {}
+
+	virtual bool parse(const Common::String &line, ScriptParseContext &parseCtx, Command *&command) override;
+	virtual void transition(ScriptParseContext &parseCtx, Command *oldCommand, Command *newCommand, CommandParser *newCommandParser) override;
+};
+
+class RandomCommand : public Command {
+	friend class RandomBlockStartParser;
+
+public:
+	typedef Common::Array<Command *> Choices;
+
+	RandomCommand(uint numChoices);
+
+	virtual ExecuteResult execute(ScriptExecutionContext &scriptExecCtx) override;
+	virtual Command *next() const override;
+
+	virtual Common::String debugString() const override;
+
+	const Choices &getChoices() const;
+
+private:
+	uint _numChoices;
+	Choices _choices;
+	Command *_chosenNext;
+};
+
+}
+
+#endif