/**
 * UI Widget Base Class
 *
 * Extends Widget with DOM manipulation and visual functionality.
 * Base for all widgets that render UI elements.
 */
import { Widget } from './Widget.js';

export class UIWidget extends Widget {
    constructor(options = {}) {
        super(options);

        // UI properties
        this.element = null;
        this.isVisible = false;
        this.isRendered = false;
        this.theme = options.theme || 'default';
        this.cssClasses = new Set(['markitect-widget']);

        // Animation support
        this.animationDuration = options.animationDuration || 300;
        this.enableAnimations = options.enableAnimations !== false;
    }

    /**
     * Render the widget to DOM (abstract method)
     */
    async render() {
        throw new Error('render() method must be implemented by subclass');
    }

    /**
     * Show the widget
     */
    async show(options = {}) {
        if (!this.isRendered) {
            await this.render();
        }

        if (this.isVisible) {
            return this;
        }

        this.isVisible = true;

        if (this.element) {
            if (this.enableAnimations && !options.immediate) {
                await this.animateShow();
            } else {
                this.element.style.display = '';
            }
        }

        this.emit('shown');
        return this;
    }

    /**
     * Hide the widget
     */
    async hide(options = {}) {
        if (!this.isVisible) {
            return this;
        }

        this.isVisible = false;

        if (this.element) {
            if (this.enableAnimations && !options.immediate) {
                await this.animateHide();
            } else {
                this.element.style.display = 'none';
            }
        }

        this.emit('hidden');
        return this;
    }

    /**
     * Toggle visibility
     */
    async toggle(options = {}) {
        return this.isVisible ? this.hide(options) : this.show(options);
    }

    /**
     * Show animation (override for custom animations)
     */
    async animateShow() {
        if (!this.element) return;

        return new Promise(resolve => {
            this.element.style.transition = `opacity ${this.animationDuration}ms ease-in-out`;
            this.element.style.opacity = '0';
            this.element.style.display = '';

            // Force reflow
            this.element.offsetHeight;

            this.element.style.opacity = '1';

            setTimeout(() => {
                this.element.style.transition = '';
                resolve();
            }, this.animationDuration);
        });
    }

    /**
     * Hide animation (override for custom animations)
     */
    async animateHide() {
        if (!this.element) return;

        return new Promise(resolve => {
            this.element.style.transition = `opacity ${this.animationDuration}ms ease-in-out`;
            this.element.style.opacity = '0';

            setTimeout(() => {
                this.element.style.display = 'none';
                this.element.style.transition = '';
                this.element.style.opacity = '';
                resolve();
            }, this.animationDuration);
        });
    }

    /**
     * CSS class management
     */
    addClass(className) {
        this.cssClasses.add(className);
        if (this.element) {
            this.element.classList.add(className);
        }
        return this;
    }

    removeClass(className) {
        this.cssClasses.delete(className);
        if (this.element) {
            this.element.classList.remove(className);
        }
        return this;
    }

    hasClass(className) {
        return this.cssClasses.has(className);
    }

    /**
     * Apply theme styling
     */
    applyTheme(themeName) {
        const oldTheme = this.theme;
        this.theme = themeName;

        this.removeClass(`theme-${oldTheme}`);
        this.addClass(`theme-${themeName}`);

        this.emit('theme-changed', { oldTheme, newTheme: themeName });
        return this;
    }

    /**
     * Find child element by selector
     */
    findElement(selector) {
        return this.element ? this.element.querySelector(selector) : null;
    }

    /**
     * Find all child elements by selector
     */
    findElements(selector) {
        return this.element ? this.element.querySelectorAll(selector) : [];
    }

    /**
     * Override destroy to clean up DOM
     */
    async destroy() {
        if (this.element && this.element.parentNode) {
            this.element.parentNode.removeChild(this.element);
        }

        this.element = null;
        this.isRendered = false;
        this.isVisible = false;

        await super.destroy();
    }

    /**
     * Apply all CSS classes to element
     */
    applyCSSClasses(element = this.element) {
        if (element) {
            element.className = Array.from(this.cssClasses).join(' ');
        }
    }

    /**
     * Default configuration for UI widgets
     */
    getDefaultConfig() {
        return {
            ...super.getDefaultConfig(),
            theme: 'default',
            animationDuration: 300,
            enableAnimations: true
        };
    }
}