package cuchaz.enigma.gui.config;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.image.BufferedImage;

import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.plaf.metal.MetalLookAndFeel;

import com.formdev.flatlaf.FlatDarkLaf;
import com.formdev.flatlaf.FlatLightLaf;
import com.formdev.flatlaf.FlatSystemProperties;

public enum LookAndFeel {
	DEFAULT(false),
	DARCULA(false),
	METAL(true),
	SYSTEM(true),
	NONE(true);

	// the "JVM default" look and feel, get it at the beginning and store it so we can set it later
	private static final javax.swing.LookAndFeel NONE_LAF = UIManager.getLookAndFeel();
	private final boolean needsScaling;
	private static Boolean isDarkLaf = null;

	LookAndFeel(boolean needsScaling) {
		this.needsScaling = needsScaling;
	}

	public boolean needsScaling() {
		// FlatLaf-based LaFs do their own scaling so we don't have to do it.
		// Running swing-dpi for FlatLaf actually breaks fonts, so we let it scale the GUI.
		return needsScaling;
	}

	public void setGlobalLAF() {
		// Configure FlatLaf's UI scale to be our scale factor.
		// This is also used for the SVG icons, so it applies even when some other LaF is active.
		System.setProperty(FlatSystemProperties.UI_SCALE, Float.toString(UiConfig.getActiveScaleFactor()));

		try {
			switch (this) {
			case NONE -> UIManager.setLookAndFeel(NONE_LAF);
			case DEFAULT -> UIManager.setLookAndFeel(new FlatLightLaf());
			case METAL -> UIManager.setLookAndFeel(new MetalLookAndFeel());
			case DARCULA -> UIManager.setLookAndFeel(new FlatDarkLaf());
			case SYSTEM -> UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
			}
		} catch (Exception e) {
			throw new Error("Failed to set global look and feel", e);
		}
	}

	public static boolean isDarkLaf() {
		if (isDarkLaf != null) {
			return isDarkLaf;
		}

		// a bit of a hack because swing doesn't give any API for that, and we need colors that aren't defined in look and feel
		JPanel panel = new JPanel();
		panel.setSize(new Dimension(10, 10));
		panel.doLayout();

		BufferedImage image = new BufferedImage(panel.getSize().width, panel.getSize().height, BufferedImage.TYPE_INT_RGB);
		panel.printAll(image.getGraphics());

		Color c = new Color(image.getRGB(0, 0));

		// convert the color we got to grayscale
		int b = (int) (0.3 * c.getRed() + 0.59 * c.getGreen() + 0.11 * c.getBlue());
		return isDarkLaf = b < 85;
	}
}