/* 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.
 *
 * $URL$
 * $Id$
 *
 */

/*
 * This code is based on original Hugo Trilogy source code
 *
 * Copyright (c) 1989-1995 David P. Gray
 *
 */

// parser.c - handles all keyboard/command input

#include "common/system.h"

#include "hugo/hugo.h"
#include "hugo/parser.h"
#include "hugo/file.h"
#include "hugo/schedule.h"
#include "hugo/util.h"
#include "hugo/sound.h"

namespace Hugo {
Parser_v1w::Parser_v1w(HugoEngine &vm) : Parser(vm) {
}

Parser_v1w::~Parser_v1w() {
}

// Test whether command line contains a verb allowed by this object.
// If it does, and the object is near and passes the tests in the command
// list then carry out the actions in the action list and return TRUE
bool Parser_v1w::isObjectVerb(object_t *obj, char *comment) {
	debugC(1, kDebugParser, "isObjectVerb(object_t *obj, %s)", comment);

	// First, find matching verb in cmd list
	uint16 cmdIndex = obj->cmdIndex;                // ptr to list of commands
	if (cmdIndex == 0)                              // No commands for this obj
		return false;

	int i;
	for (i = 0; _vm._cmdList[cmdIndex][i].verbIndex != 0; i++) {                 // For each cmd
		if (isWordPresent(_vm._arrayVerbs[_vm._cmdList[cmdIndex][i].verbIndex]))        // Was this verb used?
			break;
	}

	if (_vm._cmdList[cmdIndex][i].verbIndex == 0)   // No verbs used.
		return false;

	// Verb match found.  Check if object is Near
	char *verb = *_vm._arrayVerbs[_vm._cmdList[cmdIndex][i].verbIndex];
	if (!isNear(obj, verb, comment))
		return false;

	// Check all required objects are being carried
	cmd *cmnd = &_vm._cmdList[cmdIndex][i];         // ptr to struct cmd
	if (cmnd->reqIndex) {                           // At least 1 thing in list
		uint16 *reqs = _vm._arrayReqs[cmnd->reqIndex];      // ptr to list of required objects
		for (i = 0; reqs[i]; i++) {                 // for each obj
			if (!isCarrying(reqs[i])) {
				Utils::Box(BOX_ANY, "%s", _vm._textData[cmnd->textDataNoCarryIndex]);
				return true;
			}
		}
	}

	// Required objects are present, now check state is correct
	if ((obj->state != cmnd->reqState) && (cmnd->reqState != DONT_CARE)) {
		Utils::Box(BOX_ANY, "%s", _vm._textData[cmnd->textDataWrongIndex]);
		return true;
	}

	// Everything checked.  Change the state and carry out any actions
	if (cmnd->reqState != DONT_CARE)                // Don't change new state if required state didn't care
		obj->state = cmnd->newState;
	Utils::Box(BOX_ANY, "%s", _vm._textData[cmnd->textDataDoneIndex]);
	_vm.scheduler().insertActionList(cmnd->actIndex);

	// See if any additional generic actions
	if ((verb == _vm._arrayVerbs[_vm._look][0]) || (verb == _vm._arrayVerbs[_vm._take][0]) || (verb == _vm._arrayVerbs[_vm._drop][0]))
		isGenericVerb(obj, comment);
	return true;
}

// Test whether command line contains one of the generic actions
bool Parser_v1w::isGenericVerb(object_t *obj, char *comment) {
	debugC(1, kDebugParser, "isGenericVerb(object_t *obj, %s)", comment);

	if (!obj->genericCmd)
		return false;

	// Following is equivalent to switch, but couldn't do one
	if (isWordPresent(_vm._arrayVerbs[_vm._look]) && isNear(obj, _vm._arrayVerbs[_vm._look][0], comment)) {
		// Test state-dependent look before general look
		if ((obj->genericCmd & LOOK_S) == LOOK_S) {
			Utils::Box(BOX_ANY, "%s", _vm._textData[obj->stateDataIndex[obj->state]]);
			warning("isGenericVerb: use of state dependant look - To be validated");
		} else {
			if ((LOOK & obj->genericCmd) == LOOK) {
				if (_vm._textData[obj->dataIndex])
					Utils::Box(BOX_ANY, "%s", _vm._textData[obj->dataIndex]);
				else
					return false;
			} else {
				Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBUnusual]);
			}
		}
	} else if (isWordPresent(_vm._arrayVerbs[_vm._take]) && isNear(obj, _vm._arrayVerbs[_vm._take][0], comment)) {
		if (obj->carriedFl)
			Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBHave]);
		else if ((TAKE & obj->genericCmd) == TAKE)
			takeObject(obj);
		else if (obj->cmdIndex != 0)                // No comment if possible commands
			return false;
		else if (!obj->verbOnlyFl && (TAKE & obj->genericCmd) == TAKE)  // Make sure not taking object in context!
			Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBNoUse]);
		else
			return false;
	} else if (isWordPresent(_vm._arrayVerbs[_vm._drop])) {
		if (!obj->carriedFl && ((DROP & obj->genericCmd) == DROP))
			Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBDontHave]);
		else if (obj->carriedFl && ((DROP & obj->genericCmd) == DROP))
			dropObject(obj);
		else if (obj->cmdIndex == 0)
			Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBNeed]);
		else
			return false;
	} else {                                        // It was not a generic cmd
		return false;
	}

	return true;
}

// Test whether hero is close to object.  Return TRUE or FALSE
// If object not near, return suitable comment; may be another object close
// If radius is -1, treat radius as infinity
// Verb is included to determine correct comment if not near
bool Parser_v1w::isNear(object_t *obj, char *verb, char *comment) {
	debugC(1, kDebugParser, "isNear(object_t *obj, %s, %s)", verb, comment);

	if (obj->carriedFl)                             // Object is being carried
		return true;

	if (obj->screenIndex != *_vm._screen_p) {
		// Not in same screen
		if (obj->objValue)
			strcpy(comment, _vm._textParser[kCmtAny1]);
		else
			strcpy(comment, _vm._textParser[kCmtAny2]);
		return false;
	}

	if (obj->cycling == INVISIBLE) {
		if (obj->seqNumb) {
			// There is an image
			strcpy(comment, _vm._textParser[kCmtAny3]);
			return false;
		} else {
			// No image, assume visible
			if ((obj->radius < 0) ||
			        ((abs(obj->x - _vm._hero->x) <= obj->radius) &&
					(abs(obj->y - _vm._hero->y - _vm._hero->currImagePtr->y2) <= obj->radius))) {
				return true;
			} else {
				// User is not close enough
				if (obj->objValue && (verb != _vm._arrayVerbs[_vm._take][0]))
					strcpy(comment, _vm._textParser[kCmtAny1]);
				else
					strcpy(comment, _vm._textParser[kCmtClose]);
				return false;
			}
		}
	}

	if ((obj->radius < 0) ||
	    ((abs(obj->x - _vm._hero->x) <= obj->radius) &&
	     (abs(obj->y + obj->currImagePtr->y2 - _vm._hero->y - _vm._hero->currImagePtr->y2) <= obj->radius))) {
		return true;
	} else {
		// User is not close enough
		if (obj->objValue && (verb != _vm._arrayVerbs[_vm._take][0]))
			strcpy(comment, _vm._textParser[kCmtAny1]);
		else
			strcpy(comment, _vm._textParser[kCmtClose]);
		return false;
	}
	return true;
}

// Do all things necessary to carry an object
void Parser_v1w::takeObject(object_t *obj) {
	debugC(1, kDebugParser, "takeObject(object_t *obj)");

	obj->carriedFl = true;
	if (obj->seqNumb) {                             // Don't change if no image to display
		obj->cycling = INVISIBLE;
	}
	_vm.adjustScore(obj->objValue);

	if (obj->seqNumb > 0)                               // If object has an image, force walk to dropped
		obj->viewx = -1;                                // (possibly moved) object next time taken!
	Utils::Box(BOX_ANY, TAKE_TEXT, _vm._arrayNouns[obj->nounIndex][TAKE_NAME]);
}

// Do all necessary things to drop an object
void Parser_v1w::dropObject(object_t *obj) {
	debugC(1, kDebugParser, "dropObject(object_t *obj)");

	obj->carriedFl = false;
	obj->screenIndex = *_vm._screen_p;
	if ((obj->seqNumb > 1) || (obj->seqList[0].imageNbr > 1))
		obj->cycling = CYCLE_FORWARD;
	else
		obj->cycling = NOT_CYCLING;
	obj->x = _vm._hero->x - 1;
	obj->y = _vm._hero->y + _vm._hero->currImagePtr->y2 - 1;
	obj->y = (obj->y + obj->currImagePtr->y2 < YPIX) ? obj->y : YPIX - obj->currImagePtr->y2 - 10;
	_vm.adjustScore(-obj->objValue);
	Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBOk]);
}

// Search for matching verbs in background command list.
// Noun is not required.  Return TRUE if match found
// Note that if the background command list has match set TRUE then do not
// print text if there are any recognizable nouns in the command line
bool Parser_v1w::isCatchallVerb(objectList_t obj) {
	debugC(1, kDebugParser, "isCatchallVerb(object_list_t obj)");

	for (int i = 0; obj[i].verbIndex != 0; i++) {
		if (isWordPresent(_vm._arrayVerbs[obj[i].verbIndex]) && obj[i].nounIndex == 0 &&
		   (!obj[i].matchFl || !findNoun()) &&
		   ((obj[i].roomState == DONT_CARE) ||
		    (obj[i].roomState == _vm._screenStates[*_vm._screen_p]))) {
			Utils::Box(BOX_ANY, "%s", _vm.file().fetchString(obj[i].commentIndex));
			_vm.scheduler().processBonus(obj[i].bonusIndex);

			// If this is LOOK (without a noun), show any takeable objects
			if (*(_vm._arrayVerbs[obj[i].verbIndex]) == _vm._arrayVerbs[_vm._look][0])
				showTakeables();

			return true;
		}
	}
	return false;
}

// Search for matching verb/noun pairs in background command list
// Print text for possible background object.  Return TRUE if match found
bool Parser_v1w::isBackgroundWord(objectList_t obj) {
	debugC(1, kDebugParser, "isBackgroundWord(object_list_t obj)");

	for (int i = 0; obj[i].verbIndex != 0; i++) {
		if (isWordPresent(_vm._arrayVerbs[obj[i].verbIndex]) &&
		    isWordPresent(_vm._arrayNouns[obj[i].nounIndex]) &&
		    ((obj[i].roomState == DONT_CARE) ||
		     (obj[i].roomState == _vm._screenStates[*_vm._screen_p]))) {
			Utils::Box(BOX_ANY, "%s", _vm.file().fetchString(obj[i].commentIndex));
			_vm.scheduler().processBonus(obj[i].bonusIndex);
			return true;
		}
	}
	return false;
}

// Parse the user's line of text input.  Generate events as necessary
void Parser_v1w::lineHandler() {
	debugC(1, kDebugParser, "lineHandler()");

	status_t &gameStatus = _vm.getGameStatus();

	// Toggle God Mode
	if (!strncmp(_line, "PPG", 3)) {
		_vm.sound().playSound(!_vm._soundTest, BOTH_CHANNELS, HIGH_PRI);
		gameStatus.godModeFl ^= 1;
		return;
	}

	Utils::strlwr(_line);                           // Convert to lower case

	// God Mode cheat commands:
	// goto <screen>                                Takes hero to named screen
	// fetch <object name>                          Hero carries named object
	// fetch all                                    Hero carries all possible objects
	// find <object name>                           Takes hero to screen containing named object
	if (gameStatus.godModeFl) {
		// Special code to allow me to go straight to any screen
		if (strstr(_line, "goto")) {
			for (int i = 0; i < _vm._numScreens; i++) {
				if (!strcmp(&_line[strlen("goto") + 1], _vm._screenNames[i])) {
					_vm.scheduler().newScreen(i);
					return;
				}
			}
		}

		// Special code to allow me to get objects from anywhere
		if (strstr(_line, "fetch all")) {
			for (int i = 0; i < _vm._numObj; i++) {
				if (_vm._objects[i].genericCmd & TAKE)
					takeObject(&_vm._objects[i]);
			}
			return;
		}

		if (strstr(_line, "fetch")) {
			for (int i = 0; i < _vm._numObj; i++) {
				if (!strcmp(&_line[strlen("fetch") + 1], _vm._arrayNouns[_vm._objects[i].nounIndex][0])) {
					takeObject(&_vm._objects[i]);
					return;
				}
			}
		}

		// Special code to allow me to goto objects
		if (strstr(_line, "find")) {
			for (int i = 0; i < _vm._numObj; i++) {
				if (!strcmp(&_line[strlen("find") + 1], _vm._arrayNouns[_vm._objects[i].nounIndex][0])) {
					_vm.scheduler().newScreen(_vm._objects[i].screenIndex);
					return;
				}
			}
		}
	}

	// Special meta commands
	// EXIT/QUIT
	if (!strcmp("exit", _line) || strstr(_line, "quit")) {
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBExit]);
		return;
	}

	// SAVE/RESTORE
	if (!strcmp("save", _line) && gameStatus.viewState == V_PLAY) {
		_vm.file().saveGame(gameStatus.saveSlot, "Current game");
		return;
	}

	if (!strcmp("restore", _line) && (gameStatus.viewState == V_PLAY || gameStatus.viewState == V_IDLE)) {
		_vm.file().restoreGame(gameStatus.saveSlot);
		_vm.scheduler().restoreScreen(*_vm._screen_p);
		gameStatus.viewState = V_PLAY;
		return;
	}

	// Empty line
	if (*_line == '\0')                             // Empty line
		return;
	if (strspn(_line, " ") == strlen(_line))        // Nothing but spaces!
		return;

	if (gameStatus.gameOverFl) {
		// No commands allowed!
		Utils::gameOverMsg();
		return;
	}

	char farComment[XBYTES * 5] = "";               // hold 5 line comment if object not nearby

	// Test for nearby objects referenced explicitly
	for (int i = 0; i < _vm._numObj; i++) {
		object_t *obj = &_vm._objects[i];
		if (isWordPresent(_vm._arrayNouns[obj->nounIndex])) {
			if (isObjectVerb(obj, farComment) || isGenericVerb(obj, farComment))
				return;
		}
	}

	// Test for nearby objects that only require a verb
	// Note comment is unused if not near.
	for (int i = 0; i < _vm._numObj; i++) {
		object_t *obj = &_vm._objects[i];
		if (obj->verbOnlyFl) {
			char contextComment[XBYTES * 5] = "";   // Unused comment for context objects
			if (isObjectVerb(obj, contextComment) || isGenericVerb(obj, contextComment))
				return;
		}
	}

	// No objects match command line, try background and catchall commands
	if (isBackgroundWord(_vm._backgroundObjects[*_vm._screen_p]))
		return;
	if (isCatchallVerb(_vm._backgroundObjects[*_vm._screen_p]))
		return;
	if (isBackgroundWord(_vm._catchallList))
		return;
	if (isCatchallVerb(_vm._catchallList))
		return;

	// If a not-near comment was generated, print it
	if (*farComment != '\0') {
		Utils::Box(BOX_ANY, "%s", farComment);
		return;
	}

	// Nothing matches.  Report recognition success to user.
	char *verb = findVerb();
	char *noun = findNoun();
	if (verb == _vm._arrayVerbs[_vm._look][0] && _maze.enabledFl) {
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBMaze]);
		showTakeables();
	} else if (verb && noun) {                      // A combination I didn't think of
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBNoPoint]);
	} else if (noun) {
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBNoun]);
	} else if (verb) {
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBVerb]);
	} else {
		Utils::Box(BOX_ANY, "%s", _vm._textParser[kTBEh]);
	}
}

} // End of namespace Hugo