// file: Tauri/game-reflex-poc/frontend/main.js
// version: 1

import init, { ReflexWasmGame } from "./game_reflex_poc_tauri.js";

const FRAME_MS = 16;

function color(red, green, blue) {
  return `rgb(${red} ${green} ${blue})`;
}

function resizeCanvas(canvas) {
  const ratio = window.devicePixelRatio || 1;
  const width = Math.max(1, Math.floor(canvas.clientWidth * ratio));
  const height = Math.max(1, Math.floor(canvas.clientHeight * ratio));
  if (canvas.width !== width || canvas.height !== height) {
    canvas.width = width;
    canvas.height = height;
  }
}

function render(game, canvas, context, score) {
  resizeCanvas(canvas);
  context.fillStyle = color(game.background_red(), game.background_green(), game.background_blue());
  context.fillRect(0, 0, canvas.width, canvas.height);

  const count = game.rectangle_count();
  for (let index = 0; index < count; index += 1) {
    context.fillStyle = color(game.rectangle_red(index), game.rectangle_green(index), game.rectangle_blue(index));
    context.fillRect(
      game.rectangle_x(index) * canvas.width,
      game.rectangle_y(index) * canvas.height,
      game.rectangle_width(index) * canvas.width,
      game.rectangle_height(index) * canvas.height,
    );
  }

  score.value = `Score : ${game.score()}`;
}

async function start() {
  await init();

  const canvas = document.querySelector("#game");
  const score = document.querySelector("#score");
  const context = canvas.getContext("2d");
  if (!(canvas instanceof HTMLCanvasElement) || !(score instanceof HTMLOutputElement) || context === null) {
    throw new Error("Reflex Tauri frontend DOM is incomplete");
  }

  const game = new ReflexWasmGame();
  canvas.addEventListener("pointerdown", (event) => {
    const bounds = canvas.getBoundingClientRect();
    const x = (event.clientX - bounds.left) / bounds.width;
    const y = (event.clientY - bounds.top) / bounds.height;
    game.pointer_down(x, y);
    render(game, canvas, context, score);
  });

  let previous = performance.now();
  function frame(now) {
    while (now - previous >= FRAME_MS) {
      game.tick();
      previous += FRAME_MS;
    }
    render(game, canvas, context, score);
    window.requestAnimationFrame(frame);
  }

  render(game, canvas, context, score);
  window.requestAnimationFrame(frame);
}

start().catch((error) => {
  console.error("Reflex Tauri WASM startup failed", error);
});