/* ScummVM - Scumm Interpreter
 * Copyright (C) 2006 The ScummVM project
 *
 * Copyright (C) 1999-2003 Sarien Team
 *
 * 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.
 *
 * $URL$
 * $Id$
 *
 */

#include "common/stdafx.h"

#include "agi/agi.h"
#include "agi/keyboard.h"
#include "agi/opcodes.h"

namespace Agi {

static uint8 test_obj_right(uint8, uint8, uint8, uint8, uint8);
static uint8 test_obj_centre(uint8, uint8, uint8, uint8, uint8);
static uint8 test_obj_in_box(uint8, uint8, uint8, uint8, uint8);
static uint8 test_posn(uint8, uint8, uint8, uint8, uint8);
static uint8 test_said(uint8, uint8 *);
static uint8 test_controller(uint8);
static uint8 test_keypressed(void);
static uint8 test_compare_strings(uint8, uint8);

#define ip (game.logics[lognum].cIP)
#define code (game.logics[lognum].data)

#define test_equal(v1,v2)	(getvar(v1) == (v2))
#define test_less(v1,v2)	(getvar(v1) < (v2))
#define test_greater(v1,v2)	(getvar(v1) > (v2))
#define test_isset(flag)	(getflag (flag))
#define test_has(obj)		(object_get_location (obj) == EGO_OWNED)
#define test_obj_in_room(obj,v)	(object_get_location (obj) == getvar (v))

extern int timer_hack;		/* For the timer loop in MH1 logic 153 */

static uint8 test_compare_strings(uint8 s1, uint8 s2) {
	char ms1[MAX_STRINGLEN];
	char ms2[MAX_STRINGLEN];
	int j, k, l;

	strcpy(ms1, game.strings[s1]);
	strcpy(ms2, game.strings[s2]);

	l = strlen(ms1);
	for (k = 0, j = 0; k < l; k++) {
		switch (ms1[k]) {
		case 0x20:
		case 0x09:
		case '-':
		case '.':
		case ',':
		case ':':
		case ';':
		case '!':
		case '\'':
			break;

		default:
			ms1[j++] = toupper(ms1[k]);
			break;
		}
	}
	ms1[j] = 0x0;

	l = strlen(ms2);
	for (k = 0, j = 0; k < l; k++) {
		switch (ms2[k]) {
		case 0x20:
		case 0x09:
		case '-':
		case '.':
		case ',':
		case ':':
		case ';':
		case '!':
		case '\'':
			break;

		default:
			ms2[j++] = toupper(ms2[k]);
			break;
		}
	}
	ms2[j] = 0x0;

	return !strcmp(ms1, ms2);
}

static uint8 test_keypressed() {
	int x = game.keypress;

	game.keypress = 0;
	if (!x) {
		int mode = game.input_mode;
		game.input_mode = INPUT_NONE;
		main_cycle();
		game.input_mode = mode;
	}

	if (x)
		debugC(5, kDebugLevelScripts | kDebugLevelInput, "keypress = %02x", x);

	return x;
}

static uint8 test_controller(uint8 cont) {
	return game.ev_keyp[cont].occured;
}

static uint8 test_posn(uint8 n, uint8 x1, uint8 y1, uint8 x2, uint8 y2) {
	struct vt_entry *v = &game.view_table[n];
	uint8 r;

	r = v->x_pos >= x1 && v->y_pos >= y1 && v->x_pos <= x2 && v->y_pos <= y2;

	debugC(7, kDebugLevelScripts, "(%d,%d) in (%d,%d,%d,%d): %s", v->x_pos, v->y_pos, x1, y1, x2, y2, r ? "true" : "false");

	return r;
}

static uint8 test_obj_in_box(uint8 n, uint8 x1, uint8 y1, uint8 x2, uint8 y2) {
	struct vt_entry *v = &game.view_table[n];

	return v->x_pos >= x1 &&
	    v->y_pos >= y1 && v->x_pos + v->x_size - 1 <= x2 && v->y_pos <= y2;
}

/* if n is in centre of box */
static uint8 test_obj_centre(uint8 n, uint8 x1, uint8 y1, uint8 x2, uint8 y2) {
	struct vt_entry *v = &game.view_table[n];

	return v->x_pos + v->x_size / 2 >= x1 &&
			v->x_pos + v->x_size / 2 <= x2 && v->y_pos >= y1 && v->y_pos <= y2;
}

/* if nect N is in right corner */
static uint8 test_obj_right(uint8 n, uint8 x1, uint8 y1, uint8 x2, uint8 y2) {
	struct vt_entry *v = &game.view_table[n];

	return v->x_pos + v->x_size - 1 >= x1 &&
			v->x_pos + v->x_size - 1 <= x2 && v->y_pos >= y1 && v->y_pos <= y2;
}

/* When player has entered something, it is parsed elsewhere */
static uint8 test_said(uint8 nwords, uint8 *cc) {
	int c, n = game.num_ego_words;
	int z = 0;

	if (getflag(F_said_accepted_input) || !getflag(F_entered_cli))
		return false;

	/* FR:
	 * I think the reason for the code below is to add some speed....
	 *
	 *      if (nwords != num_ego_words)
	 *              return false;
	 *
	 * In the disco scene in Larry 1 when you type "examine blonde", 
	 * inside the logic is expected ( said("examine", "blonde", "rol") )
	 * where word("rol") = 9999
	 *
	 * According to the interpreter code 9999 means that whatever the
	 * user typed should be correct, but it looks like code 9999 means that
	 * if the string is empty at this point, the entry is also correct...
	 * 
	 * With the removal of this code, the behaviour of the scene was
	 * corrected
	 */

	for (c = 0; nwords && n; c++, nwords--, n--) {
		z = READ_LE_UINT16(cc);
		cc += 2;

		switch (z) {
		case 9999:	/* rest of line (empty string counts to...) */
			nwords = 1;
			break;
		case 1:	/* any word */
			break;
		default:
			if (game.ego_words[c].id != z)
				return false;
			break;
		}
	}

	/* The entry string should be entirely parsed, or last word = 9999 */
	if (n && z != 9999)
		return false;

	/* The interpreter string shouldn't be entirely parsed, but next
	 * word must be 9999.
	 */
	if (nwords != 0 && READ_LE_UINT16(cc) != 9999)
		return false;

	setflag(F_said_accepted_input, true);

	return true;
}

int test_if_code(int lognum) {
	int ec = true;
	int retval = true;
	uint8 op = 0;
	uint8 not_test = false;
	uint8 or_test = false;
	uint16 last_ip = ip;
	uint8 p[16] = { 0 };

	while (retval && !game.quit_prog_now) {
#ifdef USE_CONSOLE
		if (debug_.enabled && (debug_.logic0 || lognum))
			debug_console(lognum, lTEST_MODE, NULL);
#endif

		last_ip = ip;
		op = *(code + ip++);
		memmove(p, (code + ip), 16);

		switch (op) {
		case 0xFF:	/* END IF, TEST true */
			goto end_test;
		case 0xFD:
			not_test = !not_test;
			continue;
		case 0xFC:	/* OR */
			/* if or_test is ON and we hit 0xFC, end of OR, then
			 * or is STILL false so break.
			 */
			if (or_test) {
				ec = false;
				retval = false;
				goto end_test;
			}

			or_test = true;
			continue;

		case 0x00:
			/* return true? */
			goto end_test;
		case 0x01:
			ec = test_equal(p[0], p[1]);
			if (p[0] == 11)
				timer_hack++;
			break;
		case 0x02:
			ec = test_equal(p[0], getvar(p[1]));
			if (p[0] == 11 || p[1] == 11)
				timer_hack++;
			break;
		case 0x03:
			ec = test_less(p[0], p[1]);
			if (p[0] == 11)
				timer_hack++;
			break;
		case 0x04:
			ec = test_less(p[0], getvar(p[1]));
			if (p[0] == 11 || p[1] == 11)
				timer_hack++;
			break;
		case 0x05:
			ec = test_greater(p[0], p[1]);
			if (p[0] == 11)
				timer_hack++;
			break;
		case 0x06:
			ec = test_greater(p[0], getvar(p[1]));
			if (p[0] == 11 || p[1] == 11)
				timer_hack++;
			break;
		case 0x07:
			ec = test_isset(p[0]);
			break;
		case 0x08:
			ec = test_isset(getvar(p[0]));
			break;
		case 0x09:
			ec = test_has(p[0]);
			break;
		case 0x0A:
			ec = test_obj_in_room(p[0], p[1]);
			break;
		case 0x0B:
			ec = test_posn(p[0], p[1], p[2], p[3], p[4]);
			break;
		case 0x0C:
			ec = test_controller(p[0]);
			break;
		case 0x0D:
			ec = test_keypressed();
			break;
		case 0x0E:
			ec = test_said(p[0], (uint8 *) code + (ip + 1));
			ip = last_ip;
			ip++;	/* skip opcode */
			ip += p[0] * 2;	/* skip num_words * 2 */
			ip++;	/* skip num_words opcode */
			break;
		case 0x0F:
			debugC(7, kDebugLevelScripts, "comparing [%s], [%s]", game.strings[p[0]], game.strings[p[1]]);
			ec = test_compare_strings(p[0], p[1]);
			break;
		case 0x10:
			ec = test_obj_in_box(p[0], p[1], p[2], p[3], p[4]);
			break;
		case 0x11:
			ec = test_obj_centre(p[0], p[1], p[2], p[3], p[4]);
			break;
		case 0x12:
			ec = test_obj_right(p[0], p[1], p[2], p[3], p[4]);
			break;
		default:
			ec = false;
			goto end_test;
		}

		if (op <= 0x12)
			ip += logic_names_test[op].num_args;

		/* exchange ec value */
		if (not_test)
			ec = !ec;

		/* not is only enabled for 1 test command */
		not_test = false;

		if (or_test && ec) {
			/* a true inside an OR statement passes
			 * ENTIRE statement scan for end of OR
			 */

			/* CM: test for opcode < 0xfc changed from 'op' to
			 *     '*(code+ip)', to avoid problem with the 0xfd (NOT)
			 *     opcode byte. Changed a bad ip += ... ip++ construct.
			 *     This should fix the crash with Larry's logic.0 code:
			 *
			 *     if ((isset(4) ||
			 *          !isset(2) ||
			 *          v30 == 2 ||
			 *          v30 == 1)) {
			 *       goto Label1;
			 *     }
			 *
			 *     The bytecode is: 
			 *     ff fc 07 04 fd 07 02 01 1e 02 01 1e 01 fc ff
			 */

			/* find end of OR */
			while (*(code + ip) != 0xFC) {
				if (*(code + ip) == 0x0E) {	/* said */
					ip++;
					/* cover count + ^words */
					ip += 1 + ((*(code + ip)) * 2);
					continue;
				}

				if (*(code + ip) < 0xFC)
					ip += logic_names_test[*(code + ip)].num_args;
				ip++;
			}
			ip++;

			or_test = false;
			retval = true;
		} else {
			retval = or_test ? retval || ec : retval && ec;
		}
	}
      end_test:

	/* if false, scan for end of IP? */
	if (retval)
		ip += 2;
	else {
		ip = last_ip;
		while (*(code + ip) != 0xff) {
			if (*(code + ip) == 0x0e) {
				ip++;
				ip += (*(code + ip)) * 2 + 1;
			} else if (*(code + ip) < 0xfc) {
				ip += logic_names_test[*(code + ip)].num_args;
				ip++;
			} else {
				ip++;
			}
		}
		ip++;		/* skip over 0xFF */
		ip += READ_LE_UINT16(code + ip) + 2;
	}

#ifdef USE_CONSOLE
	if (debug_.enabled && (debug_.logic0 || lognum))
		debug_console(lognum, 0xFF, retval ? (char *)"=true" : (char *)"=false");
#endif

	return retval;
}

}                             // End of namespace Agi