package com.ts3client.ui;

import com.formdev.flatlaf.util.UIScale;
import com.ts3client.net.HostButton;
import com.ts3client.net.PictureDownloads;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.SwingUtilities;
import java.awt.Image;
import java.io.File;
import java.util.Objects;

/**
 * The server's host button in the toolbar's corner: its own picture, fitted to the
 * toolbar's height, or TeamSpeak's host button icon while there is none (yet).
 */
final class HostButtonView extends JButton {

    /** Keeps a banner-shaped picture from crowding out the rest of the toolbar. */
    private static final int MAX_ASPECT = 6;

    private final PictureDownloads pictures;
    private final Runnable onPictureLoaded = () -> SwingUtilities.invokeLater(this::refreshIcon);
    private HostButton shown;

    HostButtonView(PictureDownloads pictures) {
        this.pictures = pictures;
        setVisible(false);
        addActionListener(e -> {
            if (shown != null && !shown.url().isEmpty()) Links.open(shown.url(), this);
        });
    }

    /** @param button the selected server's, or {@code null} to hide it */
    void show(HostButton button) {
        if (Objects.equals(button, shown)) return;
        shown = button;
        setVisible(button != null);
        if (button == null) return;
        setToolTipText(!button.tooltip().isEmpty() ? button.tooltip() : button.url().isEmpty() ? null : button.url());
        refreshIcon();
    }

    @Override
    public void addNotify() {
        super.addNotify();
        pictures.addListener(onPictureLoaded);
    }

    @Override
    public void removeNotify() {
        pictures.removeListener(onPictureLoaded);
        super.removeNotify();
    }

    private void refreshIcon() {
        if (shown == null) return;
        ImageIcon picture = shown.gfxUrl().isEmpty() ? null : picture(pictures.get(shown.gfxUrl()));
        setIcon(picture != null ? picture : Icons.of("HOSTER_BUTTON", UIScale.scale(IconTheme.TOOLBAR_SIZE)));
    }

    private static ImageIcon picture(File file) {
        if (file == null) return null;
        ImageIcon icon = new ImageIcon(file.getPath());
        int w = icon.getIconWidth();
        int h = icon.getIconHeight();
        if (w <= 0 || h <= 0) return null;
        int height = UIScale.scale(IconTheme.TOOLBAR_SIZE);
        int width = Math.min(Math.max(1, Math.round((float) w * height / h)), height * MAX_ASPECT);
        if (w == width && h == height) return icon;
        return new ImageIcon(icon.getImage().getScaledInstance(width, height, Image.SCALE_SMOOTH));
    }
}