DIRECTOR: Split out Lingo preprocessor code into a separate file

3 files changed, 334 insertions, 306 deletions

diff --git a/engines/director/lingo/lingo-preprocessor.cpp b/engines/director/lingo/lingo-preprocessor.cpp
new file mode 100644
index 0000000000..c7cc491b3d
--- /dev/null
+++ b/engines/director/lingo/lingo-preprocessor.cpp
@@ -0,0 +1,333 @@
+/* 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 "director/lingo/lingo.h"
+
+namespace Director {
+
+bool isspecial(char c) {
+	return strchr("-+*/%%^:,()><&[]", c) != NULL;
+}
+
+static Common::String nexttok(const char *s, const char **newP = nullptr) {
+	Common::String res;
+
+	// Scan first non-whitespace
+	while (*s && (*s == ' ' || *s == '\t')) // If we see a whitespace
+		s++;
+
+	if (Common::isAlnum(*s)) {
+		// Now copy everything till whitespace
+		while (*s && (Common::isAlnum(*s) || *s == '.'))
+			res += *s++;
+	} else {
+		while (*s && isspecial(*s))
+			res += *s++;
+	}
+
+	if (newP)
+		*newP = s;
+
+	return res;
+}
+
+static Common::String prevtok(const char *s, const char *lineStart, const char **newP = nullptr) {
+	Common::String res;
+
+	// Scan first non-whitespace
+	while (s >= lineStart && (*s == ' ' || *s == '\t')) // If we see a whitespace
+		s--;
+
+	// Now copy everything till whitespace
+	while (s >= lineStart && *s != ' ' && *s != '\t')
+		res = *s-- + res;
+
+	if (newP)
+		*newP = s;
+
+	return res;
+}
+
+Common::String Lingo::codePreprocessor(const char *s, bool simple) {
+	Common::String res;
+
+	// Strip comments
+	while (*s) {
+		if (*s == '-' && *(s + 1) == '-') { // At the end of the line we will have \0
+			while (*s && *s != '\n')
+				s++;
+		}
+
+		if (*s == '\r')
+			res += '\n';
+		else if (*s)
+			res += *s;
+
+		s++;
+	}
+
+	Common::String tmp(res);
+	res.clear();
+
+	// Strip trailing whitespaces
+	s = tmp.c_str();
+	while (*s) {
+		if (*s == ' ' || *s == '\t') { // If we see a whitespace
+			const char *ps = s; // Remember where we saw it
+
+			while (*ps == ' ' || *ps == '\t')	// Scan until end of whitespaces
+				ps++;
+
+			if (*ps) {	// Not end of the string
+				if (*ps == '\n') {	// If it is newline, then we continue from it
+					s = ps;
+				} else {	// It is not a newline
+					while (s != ps) {	// Add all whitespaces
+						res += *s;
+						s++;
+					}
+				}
+			}
+		}
+
+		if (*s)
+			res += *s;
+
+		s++;
+	}
+
+	if (simple)
+		return res;
+
+	tmp = res;
+	s = tmp.c_str();
+	res.clear();
+
+	// Preprocess if statements
+	// Here we add ' end if' at end of each statement, which lets us
+	// make the grammar very straightforward
+	Common::String line, tok, res1;
+	const char *lineStart, *prevEnd;
+	int iflevel = 0;
+
+	while (*s) {
+		line.clear();
+		res1.clear();
+
+		// Get next line
+		while (*s && *s != '\n') { // If we see a whitespace
+			if (*s == '\xc2') {
+				res1 += *s++;
+				if (*s == '\n') {
+					line += ' ';
+					res1 += *s++;
+				}
+			} else {
+				res1 += *s;
+				line += tolower(*s++);
+			}
+		}
+		debugC(2, kDebugLingoParse, "line: %d                         '%s'", iflevel, line.c_str());
+
+		res1 = preprocessReturn(res1);
+
+		res += res1;
+
+		if (line.size() < 4) { // If line is too small, then skip it
+			if (*s)	// copy newline symbol
+				res += *s++;
+
+			debugC(2, kDebugLingoParse, "too small");
+
+			continue;
+		}
+
+		tok = nexttok(line.c_str(), &lineStart);
+		if (tok.equals("if")) {
+			tok = prevtok(&line.c_str()[line.size() - 1], lineStart, &prevEnd);
+			debugC(2, kDebugLingoParse, "start-if <%s>", tok.c_str());
+
+			if (tok.equals("if")) {
+				debugC(2, kDebugLingoParse, "end-if");
+				tok = prevtok(prevEnd, lineStart);
+
+				if (tok.equals("end")) {
+					// do nothing, we open and close same line
+					debugC(2, kDebugLingoParse, "end-end");
+				} else {
+					iflevel++;
+				}
+			} else if (tok.equals("then")) {
+				debugC(2, kDebugLingoParse, "last-then");
+				iflevel++;
+			} else if (tok.equals("else")) {
+				debugC(2, kDebugLingoParse, "last-else");
+				iflevel++;
+			} else { // other token
+				// Now check if we have tNLELSE
+				if (!*s) {
+					iflevel++;	// end, we have to add 'end if'
+					break;
+				}
+				const char *s1 = s + 1;
+
+				while (*s1 && *s1 == '\n')
+					s1++;
+				tok = nexttok(s1);
+
+				if (tok.equalsIgnoreCase("else")) { // ignore case because it is look-ahead
+					debugC(2, kDebugLingoParse, "tNLELSE");
+					iflevel++;
+				} else {
+					debugC(2, kDebugLingoParse, "++++ end if (no nlelse after single liner)");
+					res += " end if";
+				}
+			}
+		} else if (tok.equals("else")) {
+			debugC(2, kDebugLingoParse, "start-else");
+			bool elseif = false;
+
+			tok = nexttok(lineStart);
+			if (tok.equals("if")) {
+				debugC(2, kDebugLingoParse, "second-if");
+				elseif = true;
+			} else if (tok.empty()) {
+				debugC(2, kDebugLingoParse, "lonely-else");
+				continue;
+			}
+
+			tok = prevtok(&line.c_str()[line.size() - 1], lineStart, &prevEnd);
+			debugC(2, kDebugLingoParse, "last: '%s'", tok.c_str());
+
+			if (tok.equals("if")) {
+				debugC(2, kDebugLingoParse, "end-if");
+				tok = prevtok(prevEnd, lineStart);
+
+				if (tok.equals("end")) {
+					debugC(2, kDebugLingoParse, "end-end");
+					iflevel--;
+				}
+			} else if (tok.equals("then")) {
+				debugC(2, kDebugLingoParse, "last-then");
+
+				if (elseif == false) {
+					warning("Badly nested then");
+				}
+			} else if (tok.equals("else")) {
+				debugC(2, kDebugLingoParse, "last-else");
+				if (elseif == false) {
+					warning("Badly nested else");
+				}
+			} else { // check if we have tNLELSE
+				if (!*s) {
+					break;
+				}
+				const char *s1 = s + 1;
+
+				while (*s1 && *s1 == '\n')
+					s1++;
+				tok = nexttok(s1);
+
+				if (tok.equalsIgnoreCase("else") && elseif) {
+					// Nothing to do here, same level
+					debugC(2, kDebugLingoParse, "tNLELSE");
+				} else {
+					debugC(2, kDebugLingoParse, "++++ end if (no tNLELSE)");
+					res += " end if";
+					iflevel--;
+				}
+			}
+		} else if (tok.equals("end")) {
+			debugC(2, kDebugLingoParse, "start-end");
+
+			tok = nexttok(lineStart);
+			if (tok.equals("if")) {
+				debugC(2, kDebugLingoParse, "second-if");
+				iflevel--;
+			}
+		}
+	}
+
+	for (int i = 0; i < iflevel; i++) {
+		debugC(2, kDebugLingoParse, "++++ end if (unclosed)");
+		res += "\nend if";
+	}
+
+
+	debugC(2, kDebugLingoParse, "#############\n%s\n#############", res.c_str());
+
+	return res;
+}
+
+#ifndef strcasestr
+const char *strcasestr(const char *s, const char *find) {
+	char c, sc;
+	size_t len;
+
+	if ((c = *find++) != 0) {
+		c = (char)tolower((unsigned char)c);
+		len = strlen(find);
+		do {
+			do {
+				if ((sc = *s++) == 0)
+					return (NULL);
+			} while ((char)tolower((unsigned char)sc) != c);
+		} while (scumm_strnicmp(s, find, len) != 0);
+		s--;
+	}
+	return s;
+}
+#endif
+
+Common::String Lingo::preprocessReturn(Common::String in) {
+	Common::String res, prev, next;
+	const char *ptr = in.c_str();
+	const char *beg = ptr;
+
+	while ((ptr = strcasestr(beg, "return")) != NULL) {
+		res += Common::String(beg, ptr);
+
+		if (ptr == beg)
+			prev = "";
+		else
+			prev = prevtok(ptr - 1, beg);
+
+		next = nexttok(ptr + 6); // end of 'return'
+
+		if (prev.equals("&") || prev.equals("&&") || prev.equals("=") ||
+				next.equals("&") || next.equals("&&")) {
+			res += "scummvm_"; // Turn it into scummvm_return
+		}
+
+		res += *ptr++; // We advance one character, so 'eturn' is left
+		beg = ptr;
+	}
+
+	res += Common::String(beg);
+
+	if (in.size() != res.size())
+		debugC(2, kDebugLingoParse, "RETURN: in: %s\nout: %s", in.c_str(), res.c_str());
+
+	return res;
+}
+
+} // End of namespace Director
diff --git a/engines/director/lingo/lingo.cpp b/engines/director/lingo/lingo.cpp
index 02c7060e5b..e233328160 100644
--- a/engines/director/lingo/lingo.cpp
+++ b/engines/director/lingo/lingo.cpp
@@ -217,312 +217,6 @@ void Lingo::addCode(const char *code, ScriptType type, uint16 id) {
 	}
 }
 
-bool isspecial(char c) {
-	return strchr("-+*/%%^:,()><&[]", c) != NULL;
-}
-
-static Common::String nexttok(const char *s, const char **newP = nullptr) {
-	Common::String res;
-
-	// Scan first non-whitespace
-	while (*s && (*s == ' ' || *s == '\t')) // If we see a whitespace
-		s++;
-
-	if (Common::isAlnum(*s)) {
-		// Now copy everything till whitespace
-		while (*s && (Common::isAlnum(*s) || *s == '.'))
-			res += *s++;
-	} else {
-		while (*s && isspecial(*s))
-			res += *s++;
-	}
-
-	if (newP)
-		*newP = s;
-
-	return res;
-}
-
-static Common::String prevtok(const char *s, const char *lineStart, const char **newP = nullptr) {
-	Common::String res;
-
-	// Scan first non-whitespace
-	while (s >= lineStart && (*s == ' ' || *s == '\t')) // If we see a whitespace
-		s--;
-
-	// Now copy everything till whitespace
-	while (s >= lineStart && *s != ' ' && *s != '\t')
-		res = *s-- + res;
-
-	if (newP)
-		*newP = s;
-
-	return res;
-}
-
-Common::String Lingo::codePreprocessor(const char *s, bool simple) {
-	Common::String res;
-
-	// Strip comments
-	while (*s) {
-		if (*s == '-' && *(s + 1) == '-') { // At the end of the line we will have \0
-			while (*s && *s != '\n')
-				s++;
-		}
-
-		if (*s == '\r')
-			res += '\n';
-		else if (*s)
-			res += *s;
-
-		s++;
-	}
-
-	Common::String tmp(res);
-	res.clear();
-
-	// Strip trailing whitespaces
-	s = tmp.c_str();
-	while (*s) {
-		if (*s == ' ' || *s == '\t') { // If we see a whitespace
-			const char *ps = s; // Remember where we saw it
-
-			while (*ps == ' ' || *ps == '\t')	// Scan until end of whitespaces
-				ps++;
-
-			if (*ps) {	// Not end of the string
-				if (*ps == '\n') {	// If it is newline, then we continue from it
-					s = ps;
-				} else {	// It is not a newline
-					while (s != ps) {	// Add all whitespaces
-						res += *s;
-						s++;
-					}
-				}
-			}
-		}
-
-		if (*s)
-			res += *s;
-
-		s++;
-	}
-
-	if (simple)
-		return res;
-
-	tmp = res;
-	s = tmp.c_str();
-	res.clear();
-
-	// Preprocess if statements
-	// Here we add ' end if' at end of each statement, which lets us
-	// make the grammar very straightforward
-	Common::String line, tok, res1;
-	const char *lineStart, *prevEnd;
-	int iflevel = 0;
-
-	while (*s) {
-		line.clear();
-		res1.clear();
-
-		// Get next line
-		while (*s && *s != '\n') { // If we see a whitespace
-			if (*s == '\xc2') {
-				res1 += *s++;
-				if (*s == '\n') {
-					line += ' ';
-					res1 += *s++;
-				}
-			} else {
-				res1 += *s;
-				line += tolower(*s++);
-			}
-		}
-		debugC(2, kDebugLingoParse, "line: %d                         '%s'", iflevel, line.c_str());
-
-		res1 = preprocessReturn(res1);
-
-		res += res1;
-
-		if (line.size() < 4) { // If line is too small, then skip it
-			if (*s)	// copy newline symbol
-				res += *s++;
-
-			debugC(2, kDebugLingoParse, "too small");
-
-			continue;
-		}
-
-		tok = nexttok(line.c_str(), &lineStart);
-		if (tok.equals("if")) {
-			tok = prevtok(&line.c_str()[line.size() - 1], lineStart, &prevEnd);
-			debugC(2, kDebugLingoParse, "start-if <%s>", tok.c_str());
-
-			if (tok.equals("if")) {
-				debugC(2, kDebugLingoParse, "end-if");
-				tok = prevtok(prevEnd, lineStart);
-
-				if (tok.equals("end")) {
-					// do nothing, we open and close same line
-					debugC(2, kDebugLingoParse, "end-end");
-				} else {
-					iflevel++;
-				}
-			} else if (tok.equals("then")) {
-				debugC(2, kDebugLingoParse, "last-then");
-				iflevel++;
-			} else if (tok.equals("else")) {
-				debugC(2, kDebugLingoParse, "last-else");
-				iflevel++;
-			} else { // other token
-				// Now check if we have tNLELSE
-				if (!*s) {
-					iflevel++;	// end, we have to add 'end if'
-					break;
-				}
-				const char *s1 = s + 1;
-
-				while (*s1 && *s1 == '\n')
-					s1++;
-				tok = nexttok(s1);
-
-				if (tok.equalsIgnoreCase("else")) { // ignore case because it is look-ahead
-					debugC(2, kDebugLingoParse, "tNLELSE");
-					iflevel++;
-				} else {
-					debugC(2, kDebugLingoParse, "++++ end if (no nlelse after single liner)");
-					res += " end if";
-				}
-			}
-		} else if (tok.equals("else")) {
-			debugC(2, kDebugLingoParse, "start-else");
-			bool elseif = false;
-
-			tok = nexttok(lineStart);
-			if (tok.equals("if")) {
-				debugC(2, kDebugLingoParse, "second-if");
-				elseif = true;
-			} else if (tok.empty()) {
-				debugC(2, kDebugLingoParse, "lonely-else");
-				continue;
-			}
-
-			tok = prevtok(&line.c_str()[line.size() - 1], lineStart, &prevEnd);
-			debugC(2, kDebugLingoParse, "last: '%s'", tok.c_str());
-
-			if (tok.equals("if")) {
-				debugC(2, kDebugLingoParse, "end-if");
-				tok = prevtok(prevEnd, lineStart);
-
-				if (tok.equals("end")) {
-					debugC(2, kDebugLingoParse, "end-end");
-					iflevel--;
-				}
-			} else if (tok.equals("then")) {
-				debugC(2, kDebugLingoParse, "last-then");
-
-				if (elseif == false) {
-					warning("Badly nested then");
-				}
-			} else if (tok.equals("else")) {
-				debugC(2, kDebugLingoParse, "last-else");
-				if (elseif == false) {
-					warning("Badly nested else");
-				}
-			} else { // check if we have tNLELSE
-				if (!*s) {
-					break;
-				}
-				const char *s1 = s + 1;
-
-				while (*s1 && *s1 == '\n')
-					s1++;
-				tok = nexttok(s1);
-
-				if (tok.equalsIgnoreCase("else") && elseif) {
-					// Nothing to do here, same level
-					debugC(2, kDebugLingoParse, "tNLELSE");
-				} else {
-					debugC(2, kDebugLingoParse, "++++ end if (no tNLELSE)");
-					res += " end if";
-					iflevel--;
-				}
-			}
-		} else if (tok.equals("end")) {
-			debugC(2, kDebugLingoParse, "start-end");
-
-			tok = nexttok(lineStart);
-			if (tok.equals("if")) {
-				debugC(2, kDebugLingoParse, "second-if");
-				iflevel--;
-			}
-		}
-	}
-
-	for (int i = 0; i < iflevel; i++) {
-		debugC(2, kDebugLingoParse, "++++ end if (unclosed)");
-		res += "\nend if";
-	}
-
-
-	debugC(2, kDebugLingoParse, "#############\n%s\n#############", res.c_str());
-
-	return res;
-}
-
-#ifndef strcasestr
-const char *strcasestr(const char *s, const char *find) {
-	char c, sc;
-	size_t len;
-
-	if ((c = *find++) != 0) {
-		c = (char)tolower((unsigned char)c);
-		len = strlen(find);
-		do {
-			do {
-				if ((sc = *s++) == 0)
-					return (NULL);
-			} while ((char)tolower((unsigned char)sc) != c);
-		} while (scumm_strnicmp(s, find, len) != 0);
-		s--;
-	}
-	return s;
-}
-#endif
-
-Common::String Lingo::preprocessReturn(Common::String in) {
-	Common::String res, prev, next;
-	const char *ptr = in.c_str();
-	const char *beg = ptr;
-
-	while ((ptr = strcasestr(beg, "return")) != NULL) {
-		res += Common::String(beg, ptr);
-
-		if (ptr == beg)
-			prev = "";
-		else
-			prev = prevtok(ptr - 1, beg);
-
-		next = nexttok(ptr + 6); // end of 'return'
-
-		if (prev.equals("&") || prev.equals("&&") || prev.equals("=") ||
-				next.equals("&") || next.equals("&&")) {
-			res += "scummvm_"; // Turn it into scummvm_return
-		}
-
-		res += *ptr++; // We advance one character, so 'eturn' is left
-		beg = ptr;
-	}
-
-	res += Common::String(beg);
-
-	if (in.size() != res.size())
-		debugC(2, kDebugLingoParse, "RETURN: in: %s\nout: %s", in.c_str(), res.c_str());
-
-	return res;
-}
-
 void Lingo::executeScript(ScriptType type, uint16 id, uint16 function) {
 	if (!_scriptContexts[type].contains(id)) {
 		debugC(3, kDebugLingoExec, "Request to execute non-existant script type %d id %d", type, id);
diff --git a/engines/director/module.mk b/engines/director/module.mk
index e445e576f4..06ceae0c1d 100644
--- a/engines/director/module.mk
+++ b/engines/director/module.mk
@@ -26,6 +26,7 @@ MODULE_OBJS = \
 	lingo/lingo-events.o \
 	lingo/lingo-funcs.o \
 	lingo/lingo-lex.o \
+	lingo/lingo-preprocessor.o \
 	lingo/lingo-the.o
 
 director-grammar: