// $Id$
/*
 * WorldEdit
 * Copyright (C) 2010 sk89q <http://www.sk89q.com> and contributors
 *
 * 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.sk89q.worldedit;

import com.sk89q.worldedit.blocks.*;
import com.sk89q.worldedit.foundation.Block;
import com.sk89q.worldedit.foundation.World;
import com.sk89q.worldedit.regions.Region;
import com.sk89q.worldedit.util.TreeGenerator;

import java.util.PriorityQueue;
import java.util.Random;

/**
 * Represents a world.
 *
 * @author sk89q
 */
public abstract class LocalWorld implements World, Extent {
    /**
     * Named flags to use as parameters to {@link LocalWorld#killMobs(Vector, double, int)}
     */
    public class KillFlags {
        public static final int PETS = 1 << 0;
        public static final int NPCS = 1 << 1;
        public static final int ANIMALS = 1 << 2;
        public static final int GOLEMS = 1 << 3;
        public static final int AMBIENT = 1 << 4;
        public static final int FRIENDLY = PETS | NPCS | ANIMALS | GOLEMS | AMBIENT;
        public static final int WITH_LIGHTNING = 1 << 20;
    }

    /**
     * Random generator.
     */
    protected Random random = new Random();

    /**
     * Get the name of the world.
     *
     * @return
     */
    public abstract String getName();

    /**
     * Set block type.
     *
     * @param pt
     * @param type
     * @return
     */
    @Deprecated
    public abstract boolean setBlockType(Vector pt, int type);

    /**
     * Set block type.
     *
     * @param pt
     * @param type
     * @return
     */
    @Deprecated
    public boolean setBlockTypeFast(Vector pt, int type) {
        return setBlockType(pt, type);
    }

    /**
     * Get block type.
     *
     * @param pt
     * @return
     */
    public abstract int getBlockType(Vector pt);

    /**
     * Set block data.
     *
     * @param pt
     * @param data
     */
    @Deprecated
    public abstract void setBlockData(Vector pt, int data);

    /**
     * Set block data.
     *
     * @param pt
     * @param data
     */
    @Deprecated
    public abstract void setBlockDataFast(Vector pt, int data);

    /**
     * Get biome type
     *
     * @param pt The (x, z) location to check the biome at
     * @return The biome type at the location
     */
    public abstract BiomeType getBiome(Vector2D pt);

    /**
     * Set the biome type
     * @param pt The (x, z) location to set the biome at
     * @param biome The biome type to set to
     */
    public abstract void setBiome(Vector2D pt, BiomeType biome);

    /**
     * set block type & data
     * @param pt
     * @param type
     * @param data
     * @return
     */
    @Deprecated
    public boolean setTypeIdAndData(Vector pt, int type, int data) {
        boolean ret = setBlockType(pt, type);
        setBlockData(pt, data);
        return ret;
    }

    /**
     * set block type & data
     * @param pt
     * @param type
     * @param data
     * @return
     */
    @Deprecated
    public boolean setTypeIdAndDataFast(Vector pt, int type, int data) {
        boolean ret = setBlockTypeFast(pt, type);
        setBlockDataFast(pt, data);
        return ret;
    }

    /**
     * Get block data.
     *
     * @param pt
     * @return
     */
    public abstract int getBlockData(Vector pt);

    /**
     * Get block light level.
     *
     * @param pt
     * @return
     */
    public abstract int getBlockLightLevel(Vector pt);

    /**
     * Regenerate an area.
     *
     * @param region
     * @param editSession
     * @return
     */
    public abstract boolean regenerate(Region region, EditSession editSession);

    /**
     * Attempts to accurately copy a BaseBlock's extra data to the world.
     *
     * @param pt
     * @param block
     * @return
     */
    public abstract boolean copyToWorld(Vector pt, BaseBlock block);

    /**
     * Attempts to read a BaseBlock's extra data from the world.
     *
     * @param pt
     * @param block
     * @return
     */
    public abstract boolean copyFromWorld(Vector pt, BaseBlock block);

    /**
     * Clear a chest's contents.
     *
     * @param pt
     * @return
     */
    public abstract boolean clearContainerBlockContents(Vector pt);

    /**
     * Generate a tree at a location.
     *
     * @param editSession
     * @param pt
     * @return
     * @throws MaxChangedBlocksException
     * @deprecated use {@link #generateTree(com.sk89q.worldedit.util.TreeGenerator.TreeType, EditSession, Vector)} instead
     */
    @Deprecated
    public boolean generateTree(EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        return false;
    }

    /**
     * Generate a big tree at a location.
     *
     * @param editSession
     * @param pt
     * @return
     * @throws MaxChangedBlocksException
     * @deprecated use {@link #generateTree(com.sk89q.worldedit.util.TreeGenerator.TreeType, EditSession, Vector)} instead
     */
    @Deprecated
    public boolean generateBigTree(EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        return false;
    }

    /**
     * Generate a birch tree at a location.
     *
     * @param editSession
     * @param pt
     * @return
     * @throws MaxChangedBlocksException
     * @deprecated use {@link #generateTree(com.sk89q.worldedit.util.TreeGenerator.TreeType, EditSession, Vector)} instead
     */
    @Deprecated
    public boolean generateBirchTree(EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        return false;
    }

    /**
     * Generate a redwood tree at a location.
     *
     * @param editSession
     * @param pt
     * @return
     * @throws MaxChangedBlocksException
     * @deprecated use {@link #generateTree(com.sk89q.worldedit.util.TreeGenerator.TreeType, EditSession, Vector)} instead
     */
    @Deprecated
    public boolean generateRedwoodTree(EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        return false;
    }

    /**
     * Generate a tall redwood tree at a location.
     *
     * @param editSession
     * @param pt
     * @return
     * @throws MaxChangedBlocksException
     * @deprecated use {@link #generateTree(com.sk89q.worldedit.util.TreeGenerator.TreeType, EditSession, Vector)} instead
     */
    @Deprecated
    public boolean generateTallRedwoodTree(EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        return false;
    }

    /**
     * Generates a tree
     * @param type The type of tree to generate
     * @param editSession The EditSession to pass block changes through
     * @param pt The point where the base of the tree should be located
     * @return Whether the tree generation was successful
     * @throws MaxChangedBlocksException if too many blocks were changed by the EditSession
     */
    public boolean generateTree(TreeGenerator.TreeType type, EditSession editSession, Vector pt)
            throws MaxChangedBlocksException {
        switch (type) {
            case BIG_TREE:
                return generateBigTree(editSession, pt);
            case BIRCH:
                return generateBirchTree(editSession, pt);
            case REDWOOD:
                return generateRedwoodTree(editSession, pt);
            case TALL_REDWOOD:
                return generateTallRedwoodTree(editSession, pt);
            default:
            case TREE:
                return generateTree(editSession, pt);
        }
    }

    /**
     * Drop an item.
     *
     * @param pt
     * @param item
     * @param times
     */
    public void dropItem(Vector pt, BaseItemStack item, int times) {
        for (int i = 0; i < times; ++i) {
            dropItem(pt, item);
        }
    }

    /**
     * Drop an item.
     *
     * @param pt
     * @param item
     */
    public abstract void dropItem(Vector pt, BaseItemStack item);

    /**
     * Simulate a block being mined.
     *
     * @param pt
     */
    public void simulateBlockMine(Vector pt) {
        BaseItemStack stack = BlockType.getBlockDrop(getBlockType(pt), (short) getBlockData(pt));
        if (stack == null) {
            return;
        }

        final int amount = stack.getAmount();
        if (amount > 1) {
            dropItem(pt, new BaseItemStack(stack.getType(), 1, stack.getData()), amount);
        } else {
            dropItem(pt, stack, amount);
        }
    }

    /**
     * Kill mobs in an area, excluding pet wolves.
     *
     * @param origin The center of the area to kill mobs in
     * @param radius -1 for the whole world
     * @return number of mobs killed
     */
    @Deprecated
    public int killMobs(Vector origin, int radius) {
        return killMobs(origin, radius, false);
    }

    /**
     * Kill mobs in an area.
     *
     * @param origin The center of the area to kill mobs in
     * @param radius -1 for all mobs
     * @param killPets whether to kill pets
     * @return number of mobs killed
     */
    @Deprecated
    public int killMobs(Vector origin, int radius, boolean killPets) {
        return killMobs(origin, radius, killPets ? KillFlags.PETS : 0);
    }

    /**
     * Kill mobs in an area.
     *
     * @param origin The center of the area to kill mobs in
     * @param radius -1 for all mobs
     * @param flags various flags that determine what to kill
     * @return number of mobs killed
     */
    public int killMobs(Vector origin, double radius, int flags) {
        return killMobs(origin, (int) radius, (flags & KillFlags.PETS) != 0);
    }

    /**
     * Remove entities in an area.
     *
     * @param type
     * @param origin
     * @param radius
     * @return
     */
    public abstract int removeEntities(EntityType type, Vector origin, int radius);

    /**
     * Returns whether a block has a valid ID.
     *
     * @param type
     * @return
     */
    public boolean isValidBlockType(int type) {
        return BlockType.fromID(type) != null;
    }

    /**
     * Returns whether a block uses its data value.
     *
     * @param type block ID type
     * @return true if the block uses data value
     */
    public boolean usesBlockData(int type) {
        // We future proof here by assuming all unknown blocks use data
        return BlockType.usesData(type) || BlockType.fromID(type) == null;
    }

    /**
     * Checks if the chunk pt is in is loaded. if not, loads the chunk
     *
     * @param pt Position to check
     */
    public void checkLoadedChunk(Vector pt) {
    }

    /**
     * Compare if the other world is equal.
     *
     * @param other
     * @return
     */
    @Override
    public abstract boolean equals(Object other);

    /**
     * Hash code.
     *
     * @return
     */
    @Override
    public abstract int hashCode();

    /**
     * Get the world's height
     *
     * @return
     */
    public int getMaxY() {
        return 255;
    }

    /**
     * Does some post-processing. Should be called after using fast mode
     *
     * @param chunks the chunks to fix
     */
    public void fixAfterFastMode(Iterable<BlockVector2D> chunks) {
    }

    public void fixLighting(Iterable<BlockVector2D> chunks) {
    }

    /**
     * Plays the minecraft effect with the given type and data at the given position.
     *
     * @param position
     * @param type
     * @param data
     */
    public boolean playEffect(Vector position, int type, int data) {
        return false;
    }

    private class QueuedEffect implements Comparable<QueuedEffect> {
        private final Vector position;
        private final int blockId;
        private final double priority;
        public QueuedEffect(Vector position, int blockId, double priority) {
            this.position = position;
            this.blockId = blockId;
            this.priority = priority;
        }

        public void play() {
            playEffect(position, 2001, blockId);
        }

        @Override
        public int compareTo(QueuedEffect other) {
            return Double.compare(priority, other.priority);
        }
    }

    private final PriorityQueue<QueuedEffect> effectQueue = new PriorityQueue<QueuedEffect>();
    private int taskId = -1;
    public boolean queueBlockBreakEffect(ServerInterface server, Vector position, int blockId, double priority) {
        if (taskId == -1) {
            taskId = server.schedule(0, 1, new Runnable() {
                @Override
                public void run() {
                    int max = Math.max(1, Math.min(30, effectQueue.size() / 3));
                    for (int i = 0; i < max; ++i) {
                        if (effectQueue.isEmpty()) return;

                        effectQueue.poll().play();
                    }
                }
            });
        }

        if (taskId == -1) {
            return false;
        }

        effectQueue.offer(new QueuedEffect(position, blockId, priority));

        return true;
    }

    public LocalEntity[] getEntities(Region region) {
        return new LocalEntity[0];
    }

    public int killEntities(LocalEntity... entities) {
        return 0;
    }

    @Override
    public boolean setBlock(Vector pt, BaseBlock block, boolean notifyAdjacent) {
        return setBlock(pt, (Block) block, notifyAdjacent);
    }
    
    @Override
    public boolean setBlock(Vector pt, Block block, boolean notifyAdjacent) {
        boolean successful;
        
        // Default implementation will call the old deprecated methods
        if (notifyAdjacent) {
            successful = setTypeIdAndData(pt, block.getId(), block.getData());
        } else {
            successful = setTypeIdAndDataFast(pt, block.getId(), block.getData());
        }
        
        if (block instanceof BaseBlock) {
            copyToWorld(pt, (BaseBlock) block);
        }
        
        return successful;
    }

    @Override
    public BaseBlock getBlock(Vector pt) {
        checkLoadedChunk(pt);

        int type = getBlockType(pt);
        int data = getBlockData(pt);

        switch (type) {
        case BlockID.WALL_SIGN:
        case BlockID.SIGN_POST: {
            SignBlock block = new SignBlock(type, data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.CHEST: {
            ChestBlock block = new ChestBlock(data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.FURNACE:
        case BlockID.BURNING_FURNACE: {
            FurnaceBlock block = new FurnaceBlock(type, data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.DISPENSER: {
            DispenserBlock block = new DispenserBlock(data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.MOB_SPAWNER: {
            MobSpawnerBlock block = new MobSpawnerBlock(data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.NOTE_BLOCK: {
            NoteBlock block = new NoteBlock(data);
            copyFromWorld(pt, block);
            return block;
        }

        case BlockID.HEAD: {
            SkullBlock block = new SkullBlock(data);
            copyFromWorld(pt, block);
            return block;
        }

        default:
            return new BaseBlock(type, data);
        }
    }
}