package net.knarcraft.placeholdersigns.runnable;

import me.clip.placeholderapi.PlaceholderAPI;
import net.knarcraft.knarlib.property.ColorConversion;
import net.knarcraft.knarlib.util.ColorHelper;
import net.knarcraft.placeholdersigns.PlaceholderSigns;
import net.knarcraft.placeholdersigns.container.PlaceholderSign;
import net.knarcraft.placeholdersigns.container.QueuedPlaceholderSign;
import net.knarcraft.placeholdersigns.handler.PlaceholderSignHandler;
import net.knarcraft.placeholdersigns.handler.PlaceholderSignUpdateQueueHandler;
import org.bukkit.Location;
import org.bukkit.block.Sign;
import org.bukkit.block.sign.Side;
import org.bukkit.block.sign.SignSide;
import org.jetbrains.annotations.NotNull;

import java.util.Map;

/**
 * A runnable that updates signs
 */
public class SignUpdate implements Runnable {

    private final @NotNull PlaceholderSignHandler signHandler;

    /**
     * Instantiates a new sign update runnable
     *
     * @param signHandler <p>The sign handler to get signs from</p>
     */
    public SignUpdate(@NotNull PlaceholderSignHandler signHandler) {
        this.signHandler = signHandler;
    }

    @Override
    public void run() {
        PlaceholderSigns instance = PlaceholderSigns.getInstance();
        PlaceholderSignUpdateQueueHandler queueHandler = instance.getUpdateQueueHandler();

        long startTime = System.nanoTime();
        long currentTime = System.currentTimeMillis();
        while (queueHandler.peekQueue() != null && System.nanoTime() - startTime < 25000000) {
            PlaceholderSign placeholderSign = instance.getUpdateQueueHandler().pollQueue();
            if (placeholderSign == null) {
                break;
            }

            updatePlaceholderSign(placeholderSign, currentTime);
        }
    }

    /**
     * Updates the contents of a single placeholder sign
     *
     * @param placeholderSign <p>The placeholder sign to update</p>
     * @param currentTime     <p>The current time, used for re-queuing the sign</p>
     */
    private void updatePlaceholderSign(@NotNull PlaceholderSign placeholderSign, long currentTime) {
        PlaceholderSigns instance = PlaceholderSigns.getInstance();

        // Ignore signs away from players
        Location location = placeholderSign.getLocation();

        // If no longer a sign, remove
        if (!(location.getBlock().getState() instanceof Sign sign)) {
            this.signHandler.unregisterSign(placeholderSign);
            this.signHandler.save();
            return;
        }

        // Update placeholders
        SignSide front = sign.getSide(Side.FRONT);
        SignSide back = sign.getSide(Side.BACK);
        Map<Side, Map<Integer, String>> placeholders = placeholderSign.getPlaceholders();
        String[] frontLines = front.getLines();
        String[] backLines = back.getLines();

        // Only update the sign if the text has changed
        boolean updateNecessary = false;
        if (placeholders.get(Side.FRONT) != null) {
            updateNecessary |= updatePlaceholders(frontLines, placeholders.get(Side.FRONT), front);
        }
        if (placeholders.get(Side.BACK) != null) {
            updateNecessary |= updatePlaceholders(backLines, placeholders.get(Side.BACK), back);
        }
        if (updateNecessary) {
            sign.update();
        }

        Integer updateDelay = placeholderSign.getUpdateDelay();
        if (updateDelay == null) {
            updateDelay = instance.getSignUpdateDelay();
        }

        instance.getUpdateQueueHandler().queueSign(new QueuedPlaceholderSign(placeholderSign, currentTime + (updateDelay * 50)));
    }

    /**
     * Updates the values of placeholders on a sign
     *
     * @param lines        <p>The sign's current lines</p>
     * @param placeholders <p>The sign's original placeholder lines</p>
     * @param signSide     <p>The side of the sign to update placeholders for</p>
     * @return <p>True if text has been changed, and the sign needs to be updated</p>
     */
    private boolean updatePlaceholders(@NotNull String[] lines, @NotNull Map<Integer, String> placeholders,
                                       @NotNull SignSide signSide) {
        boolean changed = false;
        for (int i = 0; i < lines.length; i++) {
            String oldText = signSide.getLine(i);

            // The new text of the sign is either the same, or the original placeholder
            String newText;
            if (!placeholders.containsKey(i) || placeholders.get(i) == null) {
                newText = oldText;
            } else {
                newText = PlaceholderAPI.setPlaceholders(null, placeholders.get(i));
            }

            // Convert color codes
            newText = ColorHelper.translateColorCodes(newText, ColorConversion.RGB);

            // Only change the line if the text has changed
            if (!newText.equals(oldText)) {
                signSide.setLine(i, newText);
                changed = true;
            }
        }

        return changed;
    }

}