import java.awt.Color;
import java.awt.image.BufferedImage;
import java.util.Arrays;
import java.util.Collections;
import java.util.function.Supplier;
import lombok.Setter;
import net.minecraft.core.Direction;
import net.minecraft.network.protocol.Packet;
import net.minecraft.network.protocol.game.ClientboundAddEntityPacket;
import net.minecraft.network.protocol.game.ClientboundMapItemDataPacket;
import net.minecraft.network.protocol.game.ClientboundSetEntityDataPacket;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.entity.decoration.ItemFrame;
import net.minecraft.world.item.ItemStack;
import net.minecraft.world.item.Items;
import net.minecraft.world.level.saveddata.maps.MapItemSavedData.MapPatch;
import net.minecraft.world.phys.Vec3;
import org.bukkit.Bukkit;
import org.bukkit.Location;
import org.bukkit.craftbukkit.v1_18_R2.CraftWorld;
import org.bukkit.craftbukkit.v1_18_R2.entity.CraftPlayer;
import org.bukkit.entity.Player;
import org.bukkit.map.MapView;

/*
    Map packet process:
    - Create an ItemFrame entity
    - Set it to have a map item, with the map ID attached to the map item

    To spawn:
    - Send an ADD ENTITY (Spawn) packet, containing the item frame entity
    - Send a SET ENTITY DATA (Metadata) packet, containing the metadata which indicates the map ID
    - Update (see below)

    To update:
    - Send a MAP ITEM DATA packet, containing the map ID, scale, and color patch
 */
public class ImageFrame {

    private final ImageBoard board;
    private final Point position;

    private final ItemFrame nmsFrame;
    private final MapView view;

    private byte[] lastFrame; // Sure this will double the memory usage, but saves A LOT of processing time and bandwidth

    @Setter
    private Supplier<BufferedImage> imageSupplier;

    public ImageFrame(ImageBoard board, Point position) {
        this.board = board;
        this.position = position;

        Location frameLocation = board.getFrameLocation(this);

        CraftWorld world = (CraftWorld) frameLocation.getWorld();

        this.view = Bukkit.createMap(world);

        this.nmsFrame = new ItemFrame(EntityType.ITEM_FRAME, world.getHandle());
        
        this.nmsFrame.setDirection(Direction.byName(board.getDirection().name()));
        this.nmsFrame.setPos(new Vec3(frameLocation.getX(), frameLocation.getY(), frameLocation.getZ()));
        this.nmsFrame.setInvisible(true);
        this.nmsFrame.setItem(createMapItem());
    }

    private ItemStack createMapItem() {
        ItemStack item = new ItemStack(Items.FILLED_MAP);
        item.getOrCreateTag().putInt("map", view.getId()); // We can do this with Bukkit too, but this is easier
        return item;
    }

    private void sendPacket(Packet<?> packet) {
        Player player = board.getPlayer();
        ((CraftPlayer) player).getHandle().connection.send(packet);
    }

    public void draw() {
        if(imageSupplier == null) {
            return;
        }

        BufferedImage image = imageSupplier.get();

        if(image == null) {
            return;
        }

        byte[] colors = getColors(image);

        if(Arrays.equals(colors, lastFrame)) {
            return;
        }

        if(lastFrame == null) {
            // Spawn the frame
            ClientboundAddEntityPacket packet = new ClientboundAddEntityPacket(nmsFrame);
            ClientboundSetEntityDataPacket metadataPacket = new ClientboundSetEntityDataPacket(nmsFrame.getId(), nmsFrame.getEntityData(), true);

            sendPacket(packet);
            sendPacket(metadataPacket);
        }

        lastFrame = colors;

        ClientboundMapItemDataPacket mapPacket = new ClientboundMapItemDataPacket(
            view.getId(), // Map view ID
            (byte) 3,     // SCALE
            false,        // Show icons
            Collections.emptyList(), // Icons
            new MapPatch(0, 0, 128, 128, colors) // Colors
        );

        sendPacket(mapPacket);
    }

    private byte[] getColors(BufferedImage image) {
        byte[] buffer = new byte[128 * 128];
        Arrays.fill(buffer, (byte) 0);

        if (image == null) {
            return buffer;
        }

        for (int y = 0; y < image.getHeight(); y++) {
            for (int x = 0; x < image.getWidth(); x++) {
                int index = (y * 128) + x;

                buffer[index] = ColorMatcher.getColor(new Color(image.getRGB(x, y)));
            }
        }

        // System.out.println("Render time: " + (System.currentTimeMillis() - time) + "ms + (sync = " + Bukkit.isPrimaryThread() + ")");
        return buffer;
    }


    public Point getPosition() {
        return position;
    }
}