/* 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 */

#include "mm/mm1/game/spell_casting.h"
#include "mm/mm1/maps/maps.h"
#include "mm/mm1/views/combat.h"
#include "mm/mm1/globals.h"

namespace MM {
namespace MM1 {
namespace Game {

static const int8 SPELLS_SP_GEMS[47 * 2] = {
	 0,   0,  0,  0, 0, -1, 0, 0,
	 0,   1,  0,  0, 0,  0, 0, 0,
	 1,   0,  0,  0, 0,  0, 0, 1,
	 0,   0,  0,  0, 2,  0, 2, 2,
	 0,   0,  0,  3, 3,
	 4,   4,  4,  4, 4,
	10,   5,  5,  5, 5,

	 0,   0, -1,  0, 0,  0, 0, 0,
	 0,   0,  1,  0, 0,  0, 0, 0,
	-1,   0,  1, -1, 0,  0, 1, 0,
	 0,   0,  2,  0, 0,  2, 2, 2,
	 0,   0,  3,  3, 3,
	 4,   4,  4,  4, 4,
	 5, 100,  5,  5, 5
};

static const byte SPELL_FLAGS[47 * 2] = {
	 1,  1,  9,  4,  2,  4,  0,  1,
	 4,  5,  9,  0,  0,  0,  9,  9,
	 2,  4,  4,  2,  9,  9,  2,  2,
	 6,  6,  0,  0,  6, 25,  5,  2,
	17,  0,  1,  4,  4,
	17,  4,  6,  4,  2,
	 1,  1,  0,  6, 25,

	 1,  2,  9,  9,  0,  2,  2,  9,
	 9,  9,  9,  2,  2,  5,  5,  9,
	 9, 18,  1,  9,  1,  1,  1,  9,
	 9,  9,  9,  9,  2,  0,  1,  1,
	17,  0,  9,  2,  2,
	 1,  9,  2,  0,  2,
	 2,  2, 17,  1,  1
};

enum SpellFlag {
	SF_COMBAT_ONLY = 1,
	SF_NONCOMBAT_ONLY = 2,
	SF_CAST_ON = 4,
	SF_OUTDOORS_ONLY = 0x10
};

int SpellCasting::getSpellIndex(const Character *chr, int lvl, int num) {
	int lvlNum;
	int setNum = chr->_class == ARCHER || chr->_class == SORCERER ? 1 : 0;
	int spellNum = num - 1;
	for (lvlNum = 2; lvlNum <= MIN(lvl, 5); ++lvlNum)
		spellNum += 8;
	for (lvlNum = 5; lvlNum < lvl; ++lvlNum)
		spellNum += 5;

	int spellIndex = setNum * 47 + spellNum;
	return spellIndex;
}

void SpellCasting::getSpellLevelNum(int spellIndex, int &lvl, int &num) {
	int idx = spellIndex % 47;

	for (lvl = 1; lvl < 8; ++lvl) {
		int numSpells = (lvl >= 5) ? 5 : 8;
		if (idx < numSpells) {
			num = idx + 1;
			return;
		}
		idx -= numSpells;
	}

	num = -1;
}


void SpellCasting::setSpell(const Character *chr, int lvl, int num) {
	_spellState = SS_OK;

	// Figure the offset in the spell list
	int spellIndex = getSpellIndex(chr, lvl, num);

	// The required SP matches the spell level
	int requiredSp = lvl;

	if (SPELLS_SP_GEMS[spellIndex] < 0)
		// required SP increases with character's level
		requiredSp = chr->_level;

	if (SPELLS_SP_GEMS[spellIndex] < 0 && chr->_sp._current < chr->_level._current)
		_spellState = SS_NOT_ENOUGH_SP;
	else if (requiredSp > chr->_sp._current)
		_spellState = SS_NOT_ENOUGH_SP;

	int requiredGems = ABS(SPELLS_SP_GEMS[spellIndex]);
	if (_spellState == SS_OK)
		setSpell(spellIndex, requiredSp, requiredGems);

	// Supporting debugger command that enables all spells
	if (g_globals->_allSpells && _spellState != SS_COMBAT_ONLY &&
			_spellState != SS_NONCOMBAT_ONLY && _spellState != SS_OUTDOORS_ONLY) {
		_requiredSp = _requiredGems = 0;
		_spellState = SS_OK;
	}
}

void SpellCasting::setSpell(int spellIndex, int requiredSp, int requiredGems) {
	_spellIndex = spellIndex;
	_requiredSp = requiredSp;
	_requiredGems = requiredGems;
	_spellState = SS_OK;

	Maps::Map &map = *g_maps->_currentMap;

	if (!isInCombat() && SPELL_FLAGS[spellIndex] & SF_COMBAT_ONLY)
		_spellState = SS_COMBAT_ONLY;
	else if (isInCombat() && SPELL_FLAGS[spellIndex] & SF_NONCOMBAT_ONLY)
		_spellState = SS_NONCOMBAT_ONLY;
	else if ((SPELL_FLAGS[spellIndex] & SF_OUTDOORS_ONLY) &&
			!(map[Maps::MAP_ID] & 0x80))
		_spellState = SS_OUTDOORS_ONLY;
}

bool SpellCasting::hasCharTarget() const {
	return (SPELL_FLAGS[_spellIndex] & SF_CAST_ON) != 0;
}

bool SpellCasting::isMagicAllowed() const {
	return !(g_maps->_currentState & Maps::SFLAG_SPELLS_DISALLOWED);
}

Common::String SpellCasting::getSpellError() const {
	Common::String msg;
	switch (_spellState) {
	case SS_NOT_ENOUGH_SP:
		msg = STRING["dialogs.misc.not_enough_sp"];
		break;
	case SS_NOT_ENOUGH_GEMS:
		msg = STRING["dialogs.misc.not_enough_gems"];
		break;
	case SS_COMBAT_ONLY:
		msg = STRING["spells.combat_only"];
		break;
	case SS_NONCOMBAT_ONLY:
		msg = STRING["spells.noncombat_only"];
		break;
	case SS_OUTDOORS_ONLY:
		msg = STRING["spells.outdoors_only"];
		break;
	default:
		msg = STRING["spells.done"];
		break;
	}

	if (!isInCombat())
		msg = Common::String::format("*** %s ***", msg.c_str());
	return msg;
}

bool SpellCasting::isInCombat() const {
	return g_events->isPresent("Combat");
}

} // namespace Game
} // namespace MM1
} // namespace MM