'use strict';

const assert = require('node:assert/strict');
const fs = require('node:fs');
const vm = require('node:vm');
const { encode } = require('../js/apng-encoder');

function chunks(buffer) {
	const result = [];
	let offset = 8;
	while (offset < buffer.length) {
		const length = buffer.readUInt32BE(offset);
		const type = buffer.toString('ascii', offset + 4, offset + 8);
		result.push({ type, data: buffer.subarray(offset + 8, offset + 8 + length) });
		offset += length + 12;
	}
	return result;
}

const red = new Uint8Array(16);
const blue = new Uint8Array(16);
for (let index = 0; index < 16; index += 4) {
	red.set([255, 0, 0, 255], index);
	blue.set([0, 0, 255, 255], index);
}
const png = encode({
	width: 2,
	height: 2,
	frames: [
		{ rgba: red, delayNumerator: 125, delayDenominator: 1000 },
		{ rgba: blue, delayNumerator: 125, delayDenominator: 1000 },
	],
});
assert.deepEqual([...png.subarray(0, 8)], [137, 80, 78, 71, 13, 10, 26, 10]);
const parsed = chunks(png);
assert.deepEqual(parsed.map((entry) => entry.type), ['IHDR', 'acTL', 'fcTL', 'IDAT', 'fcTL', 'fdAT', 'IEND']);
assert.equal(parsed.find((entry) => entry.type === 'acTL').data.readUInt32BE(0), 2);
assert.equal(parsed[2].data.readUInt32BE(0), 0);
assert.equal(parsed[4].data.readUInt32BE(0), 1);
assert.equal(parsed[5].data.readUInt32BE(0), 2);

for (const root of ['.', 'release/UNIVERSAL_SpineViewer']) {
	const html = fs.readFileSync(root + '/viewer/spine.html', 'utf8');
	const script = html.match(/<script>([\s\S]*?)<\/script>/)[1];
	new vm.Script(script);
	assert.match(script, /addEventListener\('contextmenu'[\s\S]*generateAnimatedThumbnail\(\)/);
	assert.match(script, /const size = 400;/, 'animated output must remain fixed at 400x400');
	assert.match(script, /async function encodeAnimatedThumbnailToLimit/);
	assert.match(script, /const targetBytes = maxKilobytes \* 1024/);
	assert.match(script, /if \(buffer\.length <= targetBytes\) return/);
	assert.match(script, /count: 2, bits: 3, block: 12/);
	assert.match(script, /extension: '\.png'/);
	assert.match(script, /const totalFrames = Math\.max\(1, frameOf\(animationLength\)\)/);
	assert.match(script, /start: startFrame \/ FPS/);
	assert.match(html, /id="animatedThumbStart" type="number" min="0" step="1"/);
	assert.match(html, /id="animatedThumbEnd" type="number" min="0" step="1"/);
	assert.match(html, /data-i18n="viewer\.framesUnit"/);
	assert.match(html, /id="animatedThumbMaxSize" type="number" min="50" max="10240" step="50" value="100"/);
	assert.doesNotMatch(html, /id="animatedThumbQuality"/);
	assert.doesNotMatch(html, /viewer\.secondsUnit/);
	assert.match(html, /id="animatedThumbDialog"/);
}

console.log('PASS: APNG structure, fixed 400x400 output, quality profiles and right-click wiring');