package org.saturnclient.ui.elements;

import java.util.List;
import java.util.function.Consumer;

import org.saturnclient.config.Theme;
import org.saturnclient.ui.Element;
import org.saturnclient.ui.ElementContext;
import org.saturnclient.ui.RenderScope;
import org.saturnclient.ui.resources.Fonts;

/**
 * A row of pill buttons where exactly one is selected, such as category filters.
 */
public class ChipGroup extends Element {
    private static final int HEIGHT = 28;
    private static final int PADDING = 14;
    private static final int GAP = 8;
    private static final float TEXT_SCALE = 0.62f;

    private final List<String> options;
    private final Consumer<String> onSelect;
    private String selected;

    public ChipGroup(List<String> options, String selected, Consumer<String> onSelect) {
        this.options = options;
        this.selected = selected;
        this.onSelect = onSelect;
        this.height = HEIGHT;
        this.width = chipX(options.size()) - GAP;
    }

    @Override
    public void render(RenderScope renderScope, ElementContext ctx) {
        int font = Theme.FONT.value;
        int textY = (HEIGHT - (int) (Fonts.getHeight() * TEXT_SCALE)) / 2;

        for (int i = 0; i < options.size(); i++) {
            String option = options.get(i);
            int x = chipX(i);
            int w = chipWidth(option);
            boolean active = option.equals(selected);
            boolean hovered = ctx.isHovering(x, 0, w, HEIGHT);

            if (active) {
                renderScope.drawRoundedRectangle(x, 0, w, HEIGHT, HEIGHT / 2, Theme.ACCENT.value);
            } else {
                renderScope.drawRoundedRectangle(x, 0, w, HEIGHT, HEIGHT / 2, 1,
                        Theme.withAlpha(0.05f, Theme.FOREGROUND.value),
                        hovered ? Theme.withAlpha(0.25f, Theme.FOREGROUND.value) : Theme.getBorder());
            }

            renderScope.drawText(TEXT_SCALE, option, x + PADDING, textY, font,
                    active ? Theme.ACCENT_FG.value : Theme.PRIMARY_FG.value);
        }
    }

    @Override
    public void click(int mouseX, int mouseY) {
        for (int i = 0; i < options.size(); i++) {
            String option = options.get(i);
            int x = chipX(i);

            if (mouseX >= x && mouseX <= x + chipWidth(option)) {
                if (!option.equals(selected)) {
                    selected = option;
                    onSelect.accept(option);
                }
                return;
            }
        }
    }

    private int chipX(int index) {
        int x = 0;
        for (int i = 0; i < index; i++) {
            x += chipWidth(options.get(i)) + GAP;
        }
        return x;
    }

    private static int chipWidth(String option) {
        return (int) (Fonts.getWidth(option, Theme.FONT.value) * TEXT_SCALE) + PADDING * 2;
    }
}