// Make an enclosed pocket of background transparent, starting from a seed point inside it.
// remove-background.mjs only clears background reachable from the edge (never --holes, since Mybo's belly is
// nearly background-coloured), so a gap closed off by arms and a sign stays mint. Tolerance is tight on purpose.
const sharp = require("module").createRequire("/home/ubuntu/kalki-cli/projects/mybazaar-web/package.json")("sharp");
const [, , file, seedArg, tolArg = "12"] = process.argv;
const [sx, sy] = seedArg.split(",").map(Number), tol = +tolArg;
(async () => {
	const { data, info } = await sharp(file).ensureAlpha().raw().toBuffer({ resolveWithObject: true });
	const W = info.width, H = info.height, s = (sy * W + sx) * 4;
	const ref = [data[s], data[s + 1], data[s + 2]];
	const close = (p) => Math.abs(data[p * 4] - ref[0]) + Math.abs(data[p * 4 + 1] - ref[1]) + Math.abs(data[p * 4 + 2] - ref[2]) <= tol * 3;
	const seen = new Uint8Array(W * H), stack = [sy * W + sx];
	seen[stack[0]] = 1;
	let cleared = 0;
	while (stack.length) {
		const p = stack.pop();
		data[p * 4 + 3] = 0; cleared++;
		const x = p % W;
		for (const q of [p - W, p + W, x > 0 ? p - 1 : -1, x < W - 1 ? p + 1 : -1]) if (q >= 0 && q < W * H && !seen[q] && close(q)) { seen[q] = 1; stack.push(q); }
	}
	await sharp(data, { raw: { width: W, height: H, channels: 4 } }).png().toFile(file + ".t.png");
	require("node:fs").renameSync(file + ".t.png", file);
	console.log(`cleared ${cleared} px of rgb(${ref}) from ${sx},${sy}`);
})();