1 files changed, 131 insertions, 0 deletions

diff --git a/engines/parallaction/parser.h b/engines/parallaction/parser.h
index 79e6cf6640..7e7937fb19 100644
--- a/engines/parallaction/parser.h
+++ b/engines/parallaction/parser.h
@@ -35,6 +35,7 @@ namespace Parallaction {
 char   *parseNextToken(char *s, char *tok, uint16 count, const char *brk, bool ignoreQuotes = false);
 
 #define MAX_TOKEN_LEN	50
+extern int  _numTokens;
 extern char _tokens[][MAX_TOKEN_LEN];
 
 class Script {
@@ -63,6 +64,7 @@ typedef Common::Functor0<void> Opcode;
 typedef Common::Array<const Opcode*>	OpcodeSet;
 
 
+
 class Parser {
 
 public:
@@ -95,6 +97,7 @@ public:
 class Parallaction_ns;
 class Parallaction_br;
 
+
 class LocationParser_ns {
 
 protected:
@@ -240,6 +243,23 @@ public:
 
 };
 
+/*
+	TODO: adapt the parser to effectively use the
+	statement list provided by preprocessor as its
+	input, instead of relying on the current Script
+	class.
+
+	This would need a major rewrite of the parsing
+	system!
+
+	parseNextToken could then be sealed into the
+	PreProcessor class forever, together with the
+	_tokens[] and _numTokens stuff, now dangling as
+	global objects.
+
+	NS balloons code should be dealt with before,
+	though.
+*/
 class LocationParser_br : public LocationParser_ns {
 
 protected:
@@ -402,6 +422,117 @@ public:
 
 };
 
+
+/*
+	This simple stream is temporarily needed to hook the
+	preprocessor output to the parser. It will go away
+	when the parser is rewritten to fully exploit the
+	statement list provided by the preprocessor.
+*/
+
+class ReadStringStream : public Common::ReadStream {
+
+	char *_text;
+	uint32	_pos;
+	uint32	_size;
+
+public:
+	ReadStringStream(const Common::String &text) {
+		_text = new char[text.size() + 1];
+		strcpy(_text, text.c_str());
+		_size = text.size();
+		_pos = 0;
+	}
+
+	~ReadStringStream() {
+		delete []_text;
+	}
+
+	uint32 read(void *buffer, uint32 size) {
+		if (_pos + size > _size) {
+			size = _size - _pos;
+		}
+		memcpy(buffer, _text + _pos, size);
+		_pos += size;
+		return size;
+	}
+
+	bool eos() const {
+		return _pos == _size;
+	}
+
+};
+
+
+/*
+	Demented as it may sound, the success of a parsing operation in the
+	original BRA depends on what has been parsed before. The game features
+	an innovative chaos system that involves the parser and the very game
+	engine, in order to inflict the user an unforgettable game experience.
+
+	Ok, now for the serious stuff.
+
+	The PreProcessor implemented here fixes the location scripts before
+	they are fed to the parser. It tries to do so by a preliminary scan
+	of the text file, during which a score is assigned to each statement
+	(more on this later). When the whole file has been analyzed, the
+	statements are sorted according to their score, to create a parsable
+	sequence.
+
+	For parsing, the statements in location scripts can be conveniently
+	divided into 3 groups:
+
+	* location definitions
+	* element definitions
+	* start-up commands
+
+	Since the parsing of element definitions requires location parameters
+	to be set, location definitions should be encountered first in the
+	script. Start-up commands in turn may reference elements, so they can
+	be parsed last. The first goal is to make sure the parser gets these
+	three sets in this order.
+
+	Location definitions must also be presented in a certain sequence,
+	because resource files are not fully self-describing. In short, some
+	critical game data in contained in certain files, that must obviously
+	be read before any other can be analyzed. This is the second goal.
+
+	TODO: some words about actual implementation.
+*/
+
+class StatementDef;
+
+struct StatementListNode {
+	int	_score;
+	Common::String	_name;
+	Common::String	_text;
+
+	StatementListNode(int score, const Common::String &name, const Common::String &text) : _score(score), _name(name), _text(text) { }
+
+	bool operator<(const StatementListNode& node) const {
+		return _score < node._score;
+	}
+};
+typedef Common::List<StatementListNode> StatementList;
+
+
+class PreProcessor {
+	typedef Common::List<StatementDef*> DefList;
+
+	int _numZones;
+	DefList _defs;
+
+	StatementDef* findDef(const char* name);
+	uint getDefScore(StatementDef*);
+
+public:
+	PreProcessor();
+	~PreProcessor();
+	void preprocessScript(Script &script, StatementList &list);
+};
+
+
+
 } // namespace Parallaction
 
 #endif