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

#include "m4/m4.h"
#include "m4/mads_player.h"
#include "m4/mads_scene.h"

namespace M4 {

MadsPlayer::MadsPlayer() {
	_playerPos = Common::Point(160, 78);
	_direction = 0;
	_direction2 = 0;
	_forceRefresh = true;
	_visible = true;
	_priorVisible = false;
	_visible3 = false;
	_yScale = 0;
	_moving = false;
	_spriteListIdx = 0;
	_spriteListIdx2 = 0;
	_spritesChanged = true;
	_currentScale = 0;
	strcpy(_spritesPrefix, "");
	for (int idx = 0; idx < 8; ++idx)
		_spriteSetIndexes[idx] = 0;
	_frameNum = 0;
	_frameOffset = 0;
}

/**
 * Loads the sprite set for the player
 */
bool MadsPlayer::loadSprites(const char *prefix) {
	const char suffixList[8] = { '8', '9', '6', '3', '2', '7', '4', '1' };
	char setName[80];
	bool result = true;

	if (prefix)
		strcpy(_spritesPrefix, prefix);

	_spriteSetCount = 0;
	int prefixLen = strlen(_spritesPrefix);

	if (prefixLen == 0) {
		// No player sprites at at all
		for (int idx = 0; idx < 8; ++idx)
			_spriteSetIndexes[idx] = 0;
	} else {
		strcpy(setName, "*");
		strcat(setName, _spritesPrefix);
		strcat(setName, "_0.SS");

		char *digitP = strchr(setName, '_') + 1;

		for (int idx = 0; idx < 8; ++idx) {
			*digitP = suffixList[idx];
			_spriteSetIndexes[idx] = -1;

			int setIndex = _madsVm->scene()->_spriteSlots.addSprites(setName, true);
			if (setIndex < 0) {
				if (idx < 7)
					break;
				_spriteSetIndexes[idx] = 0;
			} else {
				++_spriteSetCount;
			}

			if (idx == 0)
				_spriteListIdx = setIndex;
		}

		result = 0;
		// TODO: Unknown flag
		_spritesChanged = false;
	}

	return result;
}

/**
 * Called each frame to update the display of the player
 */
void MadsPlayer::update() {
	if (_forceRefresh || (_visible != _priorVisible)) {
		// If there's an existing player sprite visible, flag it for expiry
		int slotIndex = getSpriteSlot();
		if (slotIndex >= 0)
			_madsVm->scene()->_spriteSlots[slotIndex].spriteType = EXPIRED_SPRITE;

		// Figure out the depth for the sprite
		int newDepth = 1;
		int yp = MIN(_playerPos.y, (int16)155);
	
		for (int idx = 1; idx < 15; ++idx) {
			if (_madsVm->scene()->getSceneResources().depthTable[newDepth] >= yp)
				newDepth = idx + 1;
		}
		_currentDepth = newDepth;

		// Get the scale
		int newScale = getScale(_playerPos.y);
		_currentScale = MIN(newScale, 100);

		if (_visible) {
			// Player sprite needs to be rendered
			MadsSpriteSlot slot;
			slot.spriteType = FOREGROUND_SPRITE;
			slot.seqIndex = PLAYER_SEQ_INDEX;
			slot.spriteListIndex = _spriteListIdx + _spriteListIdx2;
			slot.frameNumber = _frameOffset + _frameNum;
			slot.xp = _playerPos.x;
			slot.yp = _playerPos.y + (_yScale * newScale) / 100;
			slot.depth = newDepth;
			slot.scale = newScale;

			if (slotIndex >= 0) {
				// Check if the existing player slot has the same details, and can be re-used
				MadsSpriteSlot &s2 = _madsVm->scene()->_spriteSlots[slotIndex];
				bool equal = (s2.seqIndex == slot.seqIndex) && (s2.spriteListIndex == slot.spriteListIndex)
					&& (s2.frameNumber == slot.frameNumber) && (s2.xp == slot.xp) && (s2.yp == slot.yp)
					&& (s2.depth == slot.depth) && (s2.scale == slot.scale);

				if (equal)
					// Undo the prior expiry of the player sprite
					slot.spriteType = SPRITE_ZERO;
				else
					slotIndex = -1;
			}

			if (slotIndex < 0) {
				// New slot needed, so allocate one and copy the slot data
				slotIndex = _madsVm->scene()->_spriteSlots.getIndex();
				_madsVm->scene()->_spriteSlots[slotIndex] = slot;
			}

			// TODO: Meaning of word_844c0 block

		}
	}

	_visible3 = _priorVisible = _visible;
	_forceRefresh = false;
}

void MadsPlayer::idle() {

}

int MadsPlayer::getScale(int yp) {
	MadsSceneResources &r = _madsVm->scene()->getSceneResources();

	int scale = (r.bandsRange() == 0) ? r._maxScale : (yp - r._yBandsStart) * r.scaleRange() / r.bandsRange()
		+ r._minScale;

	return MIN(scale, 100);
}

/**
 * Scans through the scene's sprite slot list to find any sprite displaying the player
 */
int MadsPlayer::getSpriteSlot() {
	MadsSpriteSlots &slots = _madsVm->scene()->_spriteSlots;
	for (int i = 0; i < slots.startIndex; ++i) {
		if ((slots[i].seqIndex == PLAYER_SEQ_INDEX) && (slots[i].spriteType >= SPRITE_ZERO))
			return i;
	}
	return -1;
}

} // End of namespace M4