src/parser.h

/*
	Copyright 2012-2014 Santeri Piippo
	All rights reserved.

	Redistribution and use in source and binary forms, with or without
	modification, are permitted provided that the following conditions
	are met:

	1. Redistributions of source code must retain the above copyright
	   notice, this list of conditions and the following disclaimer.
	2. Redistributions in binary form must reproduce the above copyright
	   notice, this list of conditions and the following disclaimer in the
	   documentation and/or other materials provided with the distribution.
	3. The name of the author may not be used to endorse or promote products
	   derived from this software without specific prior written permission.

	THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

#ifndef BOTC_PARSER_H
#define BOTC_PARSER_H

#include <stdio.h>
#include "main.h"
#include "commands.h"
#include "lexer_scanner.h"
#include "tokens.h"

#define MAX_SCOPE 32
#define MAX_CASE 64
#define MAX_MARKS 512 // TODO: get rid of this

class data_buffer;
class lexer;
class script_variable;

struct undefined_label
{
	string		name;
	byte_mark*	target;
};

// ============================================================================
// Operators
//
enum operator_e
{
	OPER_ADD,
	OPER_SUBTRACT,
	OPER_MULTIPLY,
	OPER_DIVIDE,
	OPER_MODULUS,
	OPER_ASSIGN,
	OPER_ASSIGNADD,
	OPER_ASSIGNSUB,
	OPER_ASSIGNMUL,
	OPER_ASSIGNDIV,
	OPER_ASSIGNMOD, // -- 10
	OPER_EQUALS,
	OPER_NOTEQUALS,
	OPER_LESSTHAN,
	OPER_GREATERTHAN,
	OPER_LESSTHANEQUALS,
	OPER_GREATERTHANEQUALS,
	OPER_LEFTSHIFT,
	OPER_RIGHTSHIFT,
	OPER_ASSIGNLEFTSHIFT,
	OPER_ASSIGNRIGHTSHIFT, // -- 20
	OPER_OR,
	OPER_AND,
	OPER_BITWISEOR,
	OPER_BITWISEAND,
	OPER_BITWISEEOR,
	OPER_TERNARY,
	OPER_STRLEN,
};

// ============================================================================
//
struct operator_info
{
	operator_e		opercode;
	e_data_header	dataheader;
	e_token			token;
};

// ============================================================================
// Mark types
//
enum marktype_e
{
	e_label_mark,
	e_if_mark,
	e_internal_mark, // internal structures
};

// ============================================================================
// Scope types
//
enum scopetype_e
{
	e_unknown_scope,
	e_if_scope,
	e_while_scope,
	e_for_scope,
	e_do_scope,
	e_switch_scope,
	e_else_scope,
};

// ============================================================================
// Meta-data about scopes
//
struct ScopeInfo
{
	byte_mark*		mark1;
	byte_mark*		mark2;
	scopetype_e		type;
	data_buffer*	buffer1;

	// switch-related stuff
	// Which case are we at?
	int				casecursor;

	// Marks to case-blocks
	byte_mark*		casemarks[MAX_CASE];

	// Numbers of the case labels
	int				casenumbers[MAX_CASE];

	// actual case blocks
	data_buffer*	casebuffers[MAX_CASE];

	// What is the current buffer of the block?
	data_buffer*	recordbuffer;
};

// ============================================================================
//
struct constant_info
{
	string name;
	type_e type;
	string val;
};

// ============================================================================
//
class botscript_parser
{
	public:
		// ====================================================================
		// METHODS
		botscript_parser();
		~botscript_parser();
		void			parse_botscript (string file_name);
		data_buffer*	parse_command (command_info* comm);
		data_buffer*	parse_expression (type_e reqtype);
		data_buffer*	parse_assignment (script_variable* var);
		int				parse_operator (bool peek = false);
		data_buffer*	parse_expr_value (type_e reqtype);
		string			parse_float();
		void			push_scope();
		data_buffer*	parse_statement();
		void			add_switch_case (data_buffer* b);
		void			check_toplevel();
		void			check_not_toplevel();
		bool			token_is (e_token a);
		string			token_string();
		string			describe_position() const;
		void			write_to_file (string outfile);

		inline int get_num_events() const
		{
			return m_num_events;
		}

		inline int get_num_states() const
		{
			return m_num_states;
		}

	private:
		// The lexer we're using.
		lexer*					m_lx;

		// The main buffer - the contents of this is what we
		// write to file after parsing is complete
		data_buffer*			m_main_buffer;

		// onenter buffer - the contents of the onenter{} block
		// is buffered here and is merged further at the end of state
		data_buffer*			m_on_enter_buffer;

		// Mainloop buffer - the contents of the mainloop{} block
		// is buffered here and is merged further at the end of state
		data_buffer*			m_main_loop_buffer;

		// Switch buffer - switch case data is recorded to this
		// buffer initially, instead of into main buffer.
		data_buffer*			m_switch_buffer;

		int						m_num_states;
		int						m_num_events;
		parsermode_e			m_current_mode;
		string					m_current_state;
		bool					m_state_spawn_defined;
		bool					m_got_main_loop;
		int						m_scope_cursor;
		data_buffer*			m_if_expression;
		bool					m_can_else;
		list<undefined_label>	m_undefined_labels;
		list<constant_info>		m_constants;

		// How many bytes have we written to file?
		int				m_num_written_bytes;

		// Scope data
		// TODO: make a list
		ScopeInfo		m_scope_stack[MAX_SCOPE];

		data_buffer*	buffer();
		constant_info*	find_constant (const string& tok);
		void			parse_state_block();
		void			parse_event_block();
		void			parse_mainloop();
		void			parse_on_enter_exit();
		void			parse_variable_declaration();
		void			parse_goto();
		void			parse_if();
		void			parse_else();
		void			parse_while_block();
		void			parse_for_block();
		void			parse_do_block();
		void			parse_switch_block();
		void			parse_switch_case();
		void			parse_switch_default();
		void			parse_break();
		void			parse_continue();
		void			parse_block_end();
		void			parse_const();
		void			parse_label();
		void			parse_eventdef();
		void			parse_funcdef();
		void			write_member_buffers();
		void			write_string_table();
};

constant_info* find_constant (const string& tok);

#endif // BOTC_PARSER_H