/**
 * Hoover — components/qr.js
 *
 * QR code SVG renderer with optional logo overlay.
 * Uses qrcode-svg library for generation.
 */

import { h } from '../vdom.js?v=9';
import { esc } from '../helpers.js?v=9';
import QRCode from '../../../vendor/qrcode-svg-1.1.0.js';

/**
 * Generate a QR code SVG string from text content.
 *
 * @param {object} props
 * @param {string} props.text        - Text to encode
 * @param {number} [props.size=200]   - QR code size in px
 * @param {number} [props.margin=2]   - Quiet zone margin
 * @param {string} [props.ecLevel='Q'] - Error correction level (L/M/Q/H)
 * @param {string} [props.logo]        - Base64 data URL for center logo
 * @param {number} [props.logoSize=40] - Logo size in px (when overlaying)
 * @param {string} [props.color]       - Foreground color (default: #000000)
 * @param {string} [props.background]  - Background color (default: #ffffff)
 * @returns {string} SVG markup string
 */
export function qrSVG(props = {}) {
    const {
        text,
        size = 200,
        margin = 2,
        ecLevel = 'Q',
        logo,
        logoSize = 40,
        color = '#000000',
        background = '#ffffff',
    } = props;

    if (!text) return '';

    const qr = new QRCode({
        content: text,
        container: 'svg',
        margin: margin,
        padding: 0,
        width: size,
        height: size,
        color: color,
        background: background,
        ecl: ecLevel,
        creambo: false,
        prettyprint: false,
    });

    let svg = qr.svg();

    // Add center logo overlay if provided
    if (logo) {
        const halfSize = size / 2;
        const halfLogo = logoSize / 2;

        const ns = 'http://www.w3.org/2000/svg';
        const parser = new DOMParser();
        const doc = parser.parseFromString(svg, 'image/svg+xml');
        const rootSvg = doc.documentElement;
        const viewBox = rootSvg.getAttribute('viewBox') || `0 0 ${size} ${size}`;

        const newSvg = doc.createElementNS(ns, 'svg');
        newSvg.setAttribute('xmlns', ns);
        newSvg.setAttribute('xmlns:xlink', 'http://www.w3.org/1999/xlink');
        newSvg.setAttribute('width', size);
        newSvg.setAttribute('height', size);
        newSvg.setAttribute('viewBox', viewBox);

        // Clone original content
        const clone = rootSvg.cloneNode(true);
        while (clone.firstChild) {
            newSvg.appendChild(clone.firstChild);
        }

        // White background behind logo
        const bgRect = doc.createElementNS(ns, 'rect');
        bgRect.setAttribute('x', halfSize - halfLogo - 4);
        bgRect.setAttribute('y', halfSize - halfLogo - 4);
        bgRect.setAttribute('width', logoSize + 8);
        bgRect.setAttribute('height', logoSize + 8);
        bgRect.setAttribute('fill', background);
        newSvg.appendChild(bgRect);

        // Logo image overlay
        const img = doc.createElementNS(ns, 'image');
        img.setAttributeNS('http://www.w3.org/1999/xlink', 'xlink:href', logo);
        img.setAttribute('x', halfSize - halfLogo);
        img.setAttribute('y', halfSize - halfLogo);
        img.setAttribute('width', logoSize);
        img.setAttribute('height', logoSize);
        newSvg.appendChild(img);

        const serializer = new XMLSerializer();
        svg = serializer.serializeToString(newSvg);
    }

    return svg;
}

/**
 * Render a QR code as a VNode with innerHTML for the SVG.
 *
 * @param {object} props
 * @param {string} props.text        - Text to encode
 * @param {number} [props.size=200]   - QR code size
 * @param {string} [props.logo]        - Base64 data URL for logo
 * @param {number} [props.logoSize=40] - Logo overlay size
 * @returns {object} VNode
 */
export function QRCodeVNode(props = {}) {
    const svgString = qrSVG(props);
    if (!svgString) {
        return h('div', {}, h('span', { class: 'text-muted' }, 'No content'));
    }
    return h('div', {
        class: 'qr-code-container text-center',
        innerHTML: svgString,
    });
}

/**
 * Logo upload widget — file input that produces base64 data URL.
 *
 * @param {object} props
 * @param {string} props.id          - Input element ID
 * @param {function} props.onChange  - Callback(logoBase64) on file select
 */
export function LogoUpload(props = {}) {
    const inputId = props.id || 'qr-logo-input';
    return h('div', { class: 'mb-2' }, [
        h('label', { class: 'form-label' }, 'Logo (optional)'),
        h('input', {
            type: 'file',
            id: inputId,
            accept: 'image/*',
            class: 'form-control',
            onChange: function (e) {
                const file = e.target.files?.[0];
                if (!file || !props.onChange) return;

                const reader = new FileReader();
                reader.onload = function (ev) {
                    props.onChange(ev.target.result);
                };
                reader.readAsDataURL(file);
            },
        }),
    ]);
}