/*
 * Pixel Dungeon
 * Copyright (C) 2012-2015 Oleg Dolya
 *
 * Shattered Pixel Dungeon
 * Copyright (C) 2014-2026 Evan Debenham
 *
 * 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/>
 */

package com.shatteredpixel.shatteredpixeldungeon.levels.rooms.quest;

import com.shatteredpixel.shatteredpixeldungeon.Dungeon;
import com.shatteredpixel.shatteredpixeldungeon.actors.mobs.Mob;
import com.shatteredpixel.shatteredpixeldungeon.actors.mobs.RotHeart;
import com.shatteredpixel.shatteredpixeldungeon.actors.mobs.RotLasher;
import com.shatteredpixel.shatteredpixeldungeon.items.keys.IronKey;
import com.shatteredpixel.shatteredpixeldungeon.levels.Level;
import com.shatteredpixel.shatteredpixeldungeon.levels.Terrain;
import com.shatteredpixel.shatteredpixeldungeon.levels.painters.Painter;
import com.shatteredpixel.shatteredpixeldungeon.levels.rooms.special.SpecialRoom;
import com.watabou.utils.PathFinder;
import com.watabou.utils.Point;
import com.watabou.utils.Random;

import java.util.ArrayList;
import java.util.Arrays;

public class RotGardenRoom extends SpecialRoom {
	
	@Override
	public int minWidth() { return 10; }
	
	@Override
	public int minHeight() { return 10; }

	public void paint( Level level ) {

		Door entrance = entrance();
		entrance.set(Door.Type.LOCKED);
		level.addItemToSpawn(new IronKey(Dungeon.depth));

		//define basic terrain, mostly high grass with some chaotically placed wall tiles
		Painter.fill(level, this, Terrain.WALL);
		Painter.set(level, entrance, Terrain.LOCKED_DOOR);

		ArrayList<Integer> candidates = new ArrayList<>();
		boolean[] passable = new boolean[level.length()];
		int entryPos = level.pointToCell(entrance());
		int openCells;
		do {
			Painter.fill(level, this, 1, Terrain.HIGH_GRASS);
			for (int i = 0; i < 12; i++) {
				Painter.set(level, random(1), Terrain.WALL);
			}
			for (int i = 0; i < 8; i++) {
				Painter.set(level, random(2), Terrain.WALL);
			}
			for (int i = 0; i < 4; i++) {
				Painter.set(level, random(3), Terrain.WALL);
			}
			Painter.drawInside(level, this, entrance, 3, Terrain.HIGH_GRASS);

			for (int i = 0; i < passable.length; i++) {
				passable[i] = level.map[i] != Terrain.WALL;
			}

			//place the heart in a slightly random location sufficiently far from the entrance
			PathFinder.buildDistanceMap(entryPos, passable);
			candidates.clear();
			openCells = 0;
			for (Point p : getPoints()) {
				int i = level.pointToCell(p);
				if (PathFinder.distance[i] != Integer.MAX_VALUE) {
					openCells++;
					if (PathFinder.distance[i] >= 7) {
						candidates.add(i);
					}
				} else {
					//fill in grass tiles that are enclosed
					if (level.map[i] == Terrain.HIGH_GRASS) {
						level.map[i] = Terrain.WALL;
					}
				}
			}
			Random.shuffle(candidates);
			int closestPos = 7;
			while (candidates.size() > 5) {
				for (Integer i : candidates.toArray(new Integer[0])) {
					if (candidates.size() > 5 && PathFinder.distance[i] == closestPos) {
						candidates.remove(i);
					}
				}
				closestPos++;
			}

		//retry if there are no distanc candidates, or more than ~half the room is closed off
		} while (candidates.isEmpty() || openCells < 35);
		int heartPos = Random.element(candidates);
		placePlant(level, heartPos, new RotHeart());

		//place up to 6 lashers in such a way that there is always a safe path to the heart
		boolean[] newPassable = Arrays.copyOf(passable, passable.length);
		int maxLashers = 6;
		for (int i = 1; i <= maxLashers; i++){
			int pos;
			int tries = 50;
			do {
				pos = level.pointToCell(random());
				tries--;
			} while (tries > 0 && !validPlantPos(passable, newPassable, level, pos, heartPos, entryPos));
			if (tries <= 0){
				break;
			}
			placePlant(level, pos, new RotLasher());
		}

		//look for open diagonals near the hard and create open cardinals near them.
		//This is important so that the heart can spread gas
		for (int i = 0; i < PathFinder.CIRCLE8.length; i+=2){
			if (level.map[heartPos + PathFinder.CIRCLE8[i]] != Terrain.WALL){
				Painter.set(level, heartPos + PathFinder.CIRCLE8[i+1], Terrain.HIGH_GRASS);
			}
		}

	}

	private static boolean validPlantPos(boolean[] passable, boolean[] newPassable, Level level, int pos, int heartPos, int entryPos){
		if (level.map[pos] != Terrain.HIGH_GRASS){
			return false;
		}

		for (int i : PathFinder.NEIGHBOURS9){
			if (level.findMob(pos+i) != null){
				return false;
			}
		}

		newPassable[pos] = false;

		//if lasher isn't near heart, we can just use cardinal directions
		if (level.distance(pos, heartPos) > 2){
			for (int i : PathFinder.NEIGHBOURS4){
				newPassable[pos+i] = false;
			}
		//if it is near, has to count as blocking all adjacent
		// so that we can guarantee a safe tile to stay still in next to the heart
		} else {
			for (int i : PathFinder.NEIGHBOURS8){
				newPassable[pos+i] = false;
			}
		}

		PathFinder.buildDistanceMap(heartPos, newPassable);

		if (PathFinder.distance[entryPos] == Integer.MAX_VALUE){
			System.arraycopy(passable, 0, newPassable, 0, passable.length);
			return false;
		} else {
			System.arraycopy(newPassable, 0, passable, 0, passable.length);
			return true;
		}
	}

	private static void placePlant(Level level, int pos, Mob plant){
		plant.pos = pos;
		level.mobs.add( plant );

		Painter.set(level, pos, Terrain.GRASS);
	}
}
