package games.coob.skywars.model;

import com.sk89q.worldedit.EditSession;
import com.sk89q.worldedit.MaxChangedBlocksException;
import com.sk89q.worldedit.WorldEdit;
import com.sk89q.worldedit.WorldEditException;
import com.sk89q.worldedit.bukkit.BukkitWorld;
import com.sk89q.worldedit.extent.clipboard.BlockArrayClipboard;
import com.sk89q.worldedit.extent.clipboard.Clipboard;
import com.sk89q.worldedit.function.operation.ForwardExtentCopy;
import com.sk89q.worldedit.function.operation.Operation;
import com.sk89q.worldedit.function.operation.RunContext;
import com.sk89q.worldedit.math.BlockVector3;
import com.sk89q.worldedit.regions.CuboidRegion;
import com.sk89q.worldedit.world.World;
import com.sk89q.worldedit.world.block.BaseBlock;
import lombok.experimental.UtilityClass;
import org.bukkit.Location;
import org.bukkit.block.Block;
import org.mineacademy.fo.Common;
import org.mineacademy.fo.collection.StrictMap;
import org.mineacademy.fo.collection.StrictSet;
import org.mineacademy.fo.model.ChunkedTask;
import org.mineacademy.fo.region.Region;

import java.util.List;

@UtilityClass
public final class ArenaMapManager {

    /**
     * Holds clipboards for saved regions (until we restore them or stop/reload/restart the server)
     */
    private final StrictMap<String, Clipboard> savedClipboards = new StrictMap<>();

    /**
     * Saves the arena region if it can be saved
     */
    public void saveRegion(final Arena arena) {
        final Region region = arena.getSettings().getRegion();

        if (region == null || !region.isWhole())
            return;

        final CuboidRegion cuboidRegion = new CuboidRegion(new BukkitWorld(region.getWorld()), toVector(region.getPrimary()), toVector(region.getSecondary()));
        final BlockArrayClipboard clipboard = new BlockArrayClipboard(cuboidRegion);

        try (EditSession editSession = createSession(cuboidRegion.getWorld())) {

            new ChunkedTask(1) {

                /**
                 * The copy operation we are using
                 */
                private Operation operation = new ForwardExtentCopy(editSession, cuboidRegion, clipboard, cuboidRegion.getMinimumPoint());

                /**
                 * Resume the operation means the operation moves forward
                 * until it can no longer be resumed
                 */
                @Override
                protected void onProcess(final int index) {
                    try {
                        operation = operation.resume(new RunContext());

                    } catch (final WorldEditException e) {
                        e.printStackTrace();
                    }
                }

                /**
                 * Return true if the operation can be resumed, ie not null
                 */
                @Override
                protected boolean canContinue(final int index) {
                    return operation != null;
                }

            }.startChain();
        }

        if (savedClipboards.contains(arena.getName()))
            savedClipboards.remove(arena.getName());

        savedClipboards.put(arena.getName(), clipboard);
    }

    /**
     * Restore arena region if it has been saved
     */
    public void restoreRegion(final Arena arena) {
        final Clipboard clipboard = savedClipboards.removeWeak(arena.getName());
        final Region region = arena.getSettings().getRegion();

        if (clipboard == null)
            return;

        try (EditSession editSession = createSession(new BukkitWorld(region.getWorld()))) {
            final List<BlockVector3> vectors = Common.convert(region.getBlocks(), ArenaMapManager::toVector);

            new ChunkedTask(150_000) {

                /**
                 * For each block in region find block stored in the clipboard,
                 * if it exists, restore it back
                 */
                @Override
                protected void onProcess(final int index) {
                    final BlockVector3 vector = vectors.get(index);
                    final BaseBlock copy = clipboard.getFullBlock(vector);

                    if (copy != null)
                        try {
                            editSession.setBlock(vector, copy);
                            editSession.close();

                        } catch (final MaxChangedBlocksException e) {
                            e.printStackTrace();
                        }
                }

                /**
                 * Flush the operation to make the blocks visible on finish
                 */
                @Override
                protected void onFinish() {
                    editSession.close();
                }

                /**
                 * Return if we can pull more blocks from our region or we are finished
                 */
                @Override
                protected boolean canContinue(final int index) {
                    return index < vectors.size();
                }

                /**
                 * Also show percentage how many blocks we have restored to finish
                 */
                @Override
                protected String getProcessMessage(final long initialTime, final int processed) {
                    final long progress = Math.round(((double) getCurrentIndex() / (double) vectors.size()) * 100);

                    return "[" + progress + "%] " + super.getProcessMessage(initialTime, processed);
                }

            }.startChain();
        }

    }

    /*
     * Create a new edit session
     */
    private EditSession createSession(final World world) {
        // session.setReorderMode(EditSession.ReorderMode.FAST); CAUSES UNDESIRABLE SIDE (PREVENTS LIGHTING OR PHYSICS UPDATES) EFFECTS BUT INCREASES SPEED
        return WorldEdit.getInstance().newEditSession(world);
    }

    /*
     * Create a WorldEdit vector from the given block
     */
    private BlockVector3 toVector(final Block block) {
        return toVector(block.getLocation());
    }

    /*
     * Create a WorldEdit vector from the given location
     */
    private BlockVector3 toVector(final Location location) {
        return BlockVector3.at(location.getX(), location.getY(), location.getZ());
    }
}