import { BadgeTemplate, BadgeLayer } from '@/types/newsletter';

// Vymazané všetky preddefinované šablóny — v systéme sú výhradne vlastné cenovky vytvorené používateľom
export const DEFAULT_BADGE_TEMPLATES: BadgeTemplate[] = [];

export interface BadgeProductData {
  priceMain: string;
  priceSub: string;
  discountText?: string;
  unitPrice?: string;
}

/**
 * Vygeneruje 100% čistý vektorový SVG reťazec cenovky bez akýchkoľvek
 * editovacích rámčekov, tooltippov či ovládacích prvkov.
 * Centy sú naformátované ako horný index (tspan dy="-0.45em").
 * Cena je predvolene bez znaku €.
 */
export function renderCleanBadgeSvg(
  template: BadgeTemplate,
  product: BadgeProductData,
  overrideWidth?: number
): string {
  const pMain = product.priceMain || '0';
  const pSub = product.priceSub || '00';
  const discount = (product.discountText || '').replace('-', '');
  const unitPrice = product.unitPrice || '';

  // Získanie viewBox alebo predvolených rozmerov
  let vb = '0 0 140 95';
  let vbWidth = 140;
  let vbHeight = 95;

  if (template.svgRaw) {
    const vbMatch = template.svgRaw.match(/viewBox=["']([^"']+)["']/i);
    if (vbMatch) {
      vb = vbMatch[1];
      const parts = vb.trim().split(/\s+/).map(Number);
      if (parts.length === 4 && parts[2] > 0 && parts[3] > 0) {
        vbWidth = parts[2];
        vbHeight = parts[3];
      }
    } else {
      const wMatch = template.svgRaw.match(/width=["']([^"']+)["']/i);
      const hMatch = template.svgRaw.match(/height=["']([^"']+)["']/i);
      if (wMatch && hMatch) {
        const w = parseFloat(wMatch[1]);
        const h = parseFloat(hMatch[1]);
        if (w > 0 && h > 0) {
          vbWidth = w;
          vbHeight = h;
          vb = `0 0 ${w} ${h}`;
        }
      }
    }
  }

  // Extrahovanie vnútorného obsahu SVG (medzi <svg...> a </svg>)
  let innerBg = '';
  if (template.svgRaw) {
    const inside = template.svgRaw.replace(/<\/?svg[^>]*>/gi, '').trim();
    innerBg = inside;
  } else {
    innerBg = `<rect width="${vbWidth}" height="${vbHeight}" rx="14" fill="#ffd100"/>`;
  }

  // Šírka výsledného SVG
  const displayWidth = overrideWidth || template.width || 110;
  const displayHeight = Math.round((displayWidth / vbWidth) * vbHeight);

  // Zostavenie textových vrstiev
  const textLayersSvg = (template.layersConfig || []).map((layer) => {
    const rawText = layer.text || '';
    const fontSize = layer.fontSize || 16;
    const subFontSize = layer.indexFontSize || Math.max(10, Math.round(fontSize * 0.55));
    const subDy = layer.indexOffsetY !== undefined ? `${layer.indexOffsetY}px` : '-0.45em';
    const subDx = layer.indexOffsetX !== undefined ? `${layer.indexOffsetX}px` : '1px';
    const revertDy = layer.indexOffsetY !== undefined ? `${-layer.indexOffsetY}px` : '0.45em';
    const fontWeight = layer.fontWeight || '700';
    const fill = layer.fill || '#ffffff';
    const fontFamily = layer.fontFamily
      ? `'${layer.fontFamily}', -apple-system, BlinkMacSystemFont, Arial, sans-serif`
      : `'Arial Narrow', Arial, sans-serif`;

    let anchor = 'middle';
    if (layer.align === 'left') anchor = 'start';
    if (layer.align === 'right') anchor = 'end';

    // Formátovanie textu: ak obsahuje {cena} alebo {centy}, centy vložíme do <tspan> ako horný index
    let contentSvg = '';
    if (rawText.includes('{cena}')) {
      const parts = rawText.split('{cena}');
      const before = escapeXml(parts[0] || '');
      const after = escapeXml(parts[1] || '');
      contentSvg = `${before}${escapeXml(pMain)}<tspan font-size="${subFontSize}px" dx="${subDx}" dy="${subDy}" font-weight="${fontWeight}">${escapeXml(pSub)}</tspan>${after ? `<tspan dy="${revertDy}">${after}</tspan>` : ''}`;
    } else if (rawText.includes('{centy}')) {
      const parts = rawText.split('{centy}');
      const before = escapeXml(parts[0] || '');
      const after = escapeXml(parts[1] || '');
      contentSvg = `${before}<tspan font-size="${subFontSize}px" dx="${subDx}" dy="${subDy}" font-weight="${fontWeight}">${escapeXml(pSub)}</tspan>${after ? `<tspan dy="${revertDy}">${after}</tspan>` : ''}`;
    } else {
      let replaced = rawText
        .replace(/{cela_suma}/g, pMain)
        .replace(/{zlava}/g, discount)
        .replace(/{jednotkova_cena}/g, unitPrice)
        .replace(/{mena}/g, '€');
      contentSvg = escapeXml(replaced);
    }

    return `<text x="${layer.x}" y="${layer.y}" text-anchor="${anchor}" dominant-baseline="central" font-family="${fontFamily}" font-size="${fontSize}px" font-weight="${fontWeight}" fill="${fill}">${contentSvg}</text>`;
  }).join('\n    ');

  return `<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="${vb}" width="${displayWidth}" height="${displayHeight}" style="display:block;max-width:100%;height:auto;">
    ${innerBg}
    ${textLayersSvg}
  </svg>`;
}

/**
 * Skonvertuje SVG reťazec do čistého PNG Data URL v prehliadači
 * (bez akýchkoľvek DOM prvkov alebo modrých drag & drop rámčekov).
 */
export async function svgToCleanPng(
  svgString: string,
  width: number,
  height: number
): Promise<string> {
  if (typeof window === 'undefined') {
    return `data:image/svg+xml;utf8,${encodeURIComponent(svgString)}`;
  }

  return new Promise((resolve) => {
    try {
      const img = new Image();
      const svgBlob = new Blob([svgString], { type: 'image/svg+xml;charset=utf-8' });
      const url = URL.createObjectURL(svgBlob);

      img.onload = () => {
        try {
          const canvas = document.createElement('canvas');
          const scale = 2; // Vysoké rozlíšenie Retina
          canvas.width = width * scale;
          canvas.height = height * scale;
          const ctx = canvas.getContext('2d');
          if (ctx) {
            ctx.scale(scale, scale);
            ctx.drawImage(img, 0, 0, width, height);
            URL.revokeObjectURL(url);
            resolve(canvas.toDataURL('image/png'));
            return;
          }
        } catch (e) {
          console.warn('Canvas export fallback to SVG data URL', e);
        }
        URL.revokeObjectURL(url);
        resolve(`data:image/svg+xml;utf8,${encodeURIComponent(svgString)}`);
      };

      img.onerror = () => {
        URL.revokeObjectURL(url);
        resolve(`data:image/svg+xml;utf8,${encodeURIComponent(svgString)}`);
      };

      img.src = url;
    } catch (err) {
      resolve(`data:image/svg+xml;utf8,${encodeURIComponent(svgString)}`);
    }
  });
}

function escapeXml(unsafe: string): string {
  if (!unsafe) return '';
  return unsafe
    .replace(/&/g, '&amp;')
    .replace(/</g, '&lt;')
    .replace(/>/g, '&gt;')
    .replace(/"/g, '&quot;')
    .replace(/'/g, '&apos;');
}