// shamelessly stolen from tobleronecord

const { createCanvas, loadImage } = require("canvas");

function canvasToBuffer(canvas) {
  return new Promise(resolve => {
    canvas.toBuffer((err, buffer) => {
      if (!err) {
        resolve(buffer);
      } else {
        throw new Error(err);
      }
    }, "image/png");
  });
}

function wrapText(context, text, x, y, maxWidth, lineHeight, preparingSentence, lines) {
  const words = text.split(/\s/g);
  for (let i = 0; i < words.length; i++) {
    const workSentence = preparingSentence.join(" ") + " " + words[i];

    if (context.measureText(workSentence).width > maxWidth) {
      lines.push(preparingSentence.join(" "));
      preparingSentence = [words[i]];
    } else {
      preparingSentence.push(words[i]);
    }
  }

  lines.push(preparingSentence.join(" "));

  lines.forEach(element => {
    const lineWidth = context.measureText(element).width;
    const xOffset = (maxWidth - lineWidth) / 2;

    y += lineHeight;
    context.fillText(element, x + xOffset, y);
  });
}

function fixUpQuote(quote, userStore) {
  const emojiRegex = /<a?:(\w+):(\d+)>/g;
  quote = quote.replace(emojiRegex, "");

  const mentionRegex = /<@(.*)>/;
  let result = quote;

  mentionRegex.exec(quote)?.forEach(match => {
    result = result.replace(match, `@${userStore.get(match.replace("<@", "").replace(">", "")).username}`);
  })

  return result.trim();
}

var preparingSentence = [];
const lines = [];

module.exports = {
  async createQuoteImage(avatarUrl, name, quoteOld, grayScale, userStore) {
    const quote = fixUpQuote(quoteOld, userStore);

    const cardWidth = 1200;
    const cardHeight = 600;

    const canvas = createCanvas(cardWidth, cardHeight);
    const ctx = canvas.getContext("2d");

    ctx.fillStyle = "#000";
    ctx.fillRect(0, 0, canvas.width, canvas.height);

    const avatar = await loadImage(avatarUrl);
    const fade = await loadImage("https://files.catbox.moe/54e96l.png");

    ctx.drawImage(avatar, 0, 0, cardHeight, cardHeight);

    if (grayScale) {
      ctx.globalCompositeOperation = "saturation";
      ctx.fillStyle = "#fff";
      ctx.fillRect(0, 0, cardWidth, cardHeight);
      ctx.globalCompositeOperation = "source-over";
    }

    ctx.drawImage(fade, cardHeight - 400, 0, 400, cardHeight);

    ctx.fillStyle = "#fff";
    ctx.font = "italic 20px Twitter Color Emoji";
    const quoteWidth = cardWidth / 2 - 50;
    const quoteX = ((cardWidth - cardHeight));
    const quoteY = cardHeight / 2 - 10;
    wrapText(ctx, `"${quote}"`, quoteX, quoteY, quoteWidth, 20, preparingSentence, lines);

    const wrappedTextHeight = lines.length * 25;

    ctx.font = "bold 16px Twitter Color Emoji";
    const authorNameX = (cardHeight * 1.5) - (ctx.measureText(`- ${name}`).width / 2) - 30;
    const authorNameY = quoteY + wrappedTextHeight + 30;

    ctx.fillText(`- ${name}`, authorNameX, authorNameY);
    preparingSentence.length = 0;
    lines.length = 0;

    return await canvasToBuffer(canvas);
  }
}