import sharp from 'sharp';
import path from 'path';

/**
 * Wraps text into multiple lines for SVG.
 */
function wrapText(text: string, maxCharsPerLine: number): string[] {
    const words = text.split(' ');
    const lines: string[] = [];
    let currentLine = '';

    words.forEach(word => {
        if ((currentLine + word).length > maxCharsPerLine) {
            lines.push(currentLine.trim());
            currentLine = word + ' ';
        } else {
            currentLine += word + ' ';
        }
    });
    lines.push(currentLine.trim());
    return lines;
}

/**
 * Generates a personalized business pitch card with text overlay.
 */
export async function generatePitchCard(text: string): Promise<Buffer> {
    const templatePath = path.resolve(__dirname, '../assets/templates/pitch_card.png');

    const lines = wrapText(text.toUpperCase(), 25);
    const lineHeight = 60;
    const startY = 540 - (lines.length * lineHeight) / 2;

    const svgText = lines.map((line, i) =>
        `<text x="540" y="${startY + (i * lineHeight)}" class="text">${line}</text>`
    ).join('');

    const svgOverlay = Buffer.from(`
    <svg width="1080" height="1080">
      <style>
        .title { 
           fill: #d4af37; 
           font-size: 56px; 
           font-family: sans-serif; 
           font-weight: 900; 
           text-anchor: middle; 
           text-transform: uppercase;
           letter-spacing: 3px;
        }
        .label {
           fill: #ffffff;
           font-size: 28px;
           font-family: sans-serif;
           font-weight: 600;
           text-anchor: middle;
           opacity: 0.8;
        }
        .text { 
           fill: #ffffff; 
           font-size: 48px; 
           font-family: sans-serif; 
           font-weight: 800; 
           text-anchor: middle; 
           letter-spacing: 1px;
        }
      </style>
      <text x="540" y="250" class="title">MA CARTE BUSINESS</text>
      <text x="540" y="440" class="label">MON PROJET :</text>
      ${svgText}
      <text x="540" y="850" class="label">XAMLÉ - 2026</text>
    </svg>`);

    return sharp(templatePath)
        .composite([{ input: svgOverlay, top: 0, left: 0 }])
        .png()
        .toBuffer();
}