GLK: ALAN2: Initial work on the Alan2 subengine

1 files changed, 87 insertions, 0 deletions

diff --git a/engines/glk/alan2/rules.cpp b/engines/glk/alan2/rules.cpp
new file mode 100644
index 0000000000..14c867133f
--- /dev/null
+++ b/engines/glk/alan2/rules.cpp
@@ -0,0 +1,87 @@
+/* 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 "glk/alan2/acode.h"
+#include "glk/alan2/interpreter.h"
+#include "glk/alan2/rules.h"
+#include "glk/alan2/types.h"
+#include "common/debug.h"
+
+namespace Glk {
+namespace Alan2 {
+
+// TODO: Refactor these into debug flags
+const bool trcflg = false;
+const bool stpflg = false;
+
+void Rules::parseRules() {
+	bool change = true;
+	int i;
+
+	for (i = 1; !endOfTable(&_ruls[i - 1]); i++)
+		_ruls[i - 1].run = false;
+
+	while (change) {
+		change = false;
+		for (i = 1; !endOfTable(&_ruls[i - 1]); i++) {
+			if (!_ruls[i - 1].run) {
+				if (trcflg) {
+					debug("\n<RULE %d (at ", i);
+					//debugsay(cur.loc);	// TODO
+					if (!stpflg)
+						debug("), Evaluating");
+					else
+						debug("), Evaluating:>\n");
+				}
+
+				_interpreter->interpret(_ruls[i - 1].exp);
+
+				if (_stack->pop()) {
+					change = true;
+					_ruls[i - 1].run = true;
+
+					if (trcflg)
+						if (!stpflg)
+							debug(", Executing:>\n");
+						else {
+							debug("\nRULE %d (at ", i);
+							//debugsay(cur.loc);	// TODO
+							debug("), Executing:>\n");
+						}
+
+					_interpreter->interpret(_ruls[i - 1].stms);
+					
+				} else if (trcflg && !stpflg) {
+					debug(":>\n");
+				}
+			}
+		}
+	}
+}
+
+bool Rules::endOfTable(RulElem *addr) {
+	Aword *x = (Aword *)addr;
+	return *x == EOF;
+}
+
+} // End of namespace Alan2
+} // Engine of namespace GLK