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

/**
 * 
 * @param {Array} images The array of images to be merged together
 * @param {function} callback The callback function to call with the merged images
 * @returns {*} A PNG encoded image
 */
exports.mergeImages = async (images, callback) => {
    if (!images) return callback(new Error("No images provided to merge"), undefined);
    const numberOfImages = images.length;
    const finalImageWidth = 1024;
    const finalImageHeight = 1024;

    switch(numberOfImages) {
        case 1:
            break;
        case 2:
            break;
        case 3:
            break;
        case 4:
            break;
        default:
            break;
    }


    const imagePosition = {
        w: 400,
        h: 88,
        x: 400,
          // Calculate the Y of the image based on the number of
          // lines in the title.
          y: titleText.length === 2 ? 75 : 100,
      };


}

// Do the same with the title's Y value.
const titleY = titleText.length === 2 ? 300 : 350;
const titleLineHeight = 100;
// And the author's Y value.
const authorY = titleText.length === 2 ? 525 : 500;

const canvas = createCanvas(width, height);
const context = canvas.getContext("2d");

context.fillStyle = "#764abc";
context.fillRect(0, 0, width, height);

context.font = "bold 70pt 'PT Sans'";
context.textAlign = "center";
context.fillStyle = "#fff";

context.fillText(titleText[0], 600, titleY);
if (titleText[1]) context.fillText(titleText[1], 600, titleY + titleLineHeight);

context.font = "40pt 'PT Sans'";
context.fillText(`by ${post.author}`, 600, authorY);

await loadImage("./assets/logo.png").then((image) => {
  const { w, h, x, y } = imagePosition;
  context.drawImage(image, x, y, w, h);
});

const buffer = canvas.toBuffer("image/png");
fs.writeFileSync("./image.png", buffer);