import { edge, node, port, variable, written } from '../lib/builders.mjs';
import { MAKE_OBJECT } from './lib/scaffold.mjs';

/**
 * More than one scene (#39): the project names the scene a run begins with – which is not the same
 * question as which scene is open in the editor – and `Load scene` swaps the running one for
 * another from inside a graph.
 *
 * What the swap keeps is the point: the scene is built from scratch, while what belongs to the
 * *run* carries on. A Variables asset is the witness, because a fresh run would put it back to
 * what it declares. The sounds of the old scene end with it – not by a rule of their own, but
 * because the behaviors playing them are destroyed like everything else in that scene.
 */

const SOURCE = { variablesAsset: 'ls-vars' };

/** `On start → Variables{set score = score + 1}`, plus `On key down g → Load scene`. */
const graphFor = (sceneId, soundId) => ({
  nodes: [
    node('ls-start', 'OnStart', 0, 0),
    node('ls-read', 'Variables', 0, 200, SOURCE, [port('score', 'number')]),
    node('ls-add', 'Add', 260, 200, { b: 1 }),
    node('ls-write', 'Variables', 560, 0, SOURCE, [written('score', 'number')]),
    node('ls-play', 'PlaySound', 820, 0, { sound: soundId, volume: 1, loop: 'true' }),
    node('ls-key', 'OnKeyDown', 0, 420, { key: 'g' }),
    node('ls-load', 'LoadScene', 260, 420, { scene: sceneId }),
  ],
  edges: [
    edge('ls-e1', 'ls-start', 'exec', 'ls-write', 'exec'),
    edge('ls-e2', 'ls-read', 'score', 'ls-add', 'a'),
    edge('ls-e3', 'ls-add', 'result', 'ls-write', 'score'),
    edge('ls-e4', 'ls-write', 'exec', 'ls-play', 'exec'),
    edge('ls-e5', 'ls-key', 'exec', 'ls-load', 'exec'),
  ],
});

export async function loadScene(t) {
  const { check, sleep, json, evaluate, mutate, click, clickText, locate, press, play, stop, shot, has } = t;
  const playInfo = () => json('__gm.playInfo()');
  const playFrom = () => json('__gm.playFrom()');
  /** The switch is opened by position: its caption is elided at the width it has. */
  const openPlayFrom = async () => {
    const at = await json('__gm.playFromAt()');
    await click(at.x, at.y);
    await sleep(250);
  };
  const stats = () => json('__gm.sound.stats()');
  const waitFor = async (read, done, tries = 25) => {
    let value = await read();
    for (let i = 0; i < tries && !done(value); i++) {
      await sleep(150);
      value = await read();
    }
    return value;
  };

  await press('Escape');
  await evaluate('__gm.state.select(null)');
  await evaluate("__gm.showTab('scene')");
  await sleep(200);

  const firstId = await json('__gm.state.project.activeSceneId');
  const firstName = await json('__gm.state.activeScene.name');

  // A sound to have something playing across the swap; the seed put the files on the server.
  const stored = await evaluate(`fetch('/game-maker/api/index.php?r=sounds').then((r) => r.json())`);
  const file = stored[0]?.file ?? '';

  // 35a. A second scene with a box of its own, a Variables asset, and the behavior that counts and
  //      loads. Everything lives in the new scene, so nothing later in the suite sees any of it.
  await mutate(`
    const p = __gm.state.project;
    const scene = __gm.state.activeScene;
    ${MAKE_OBJECT}
    const second = structuredClone(scene);
    second.id = 'ls-scene';
    second.name = 'Level 2';
    second.objects = [
      make('ls-box', 'crate', '', 0, 'Second box'),
      make('ls-brain', 'ls-logic', 'ls-box', 0, 'Loader'),
    ];
    const logic = structuredClone(p.assets.find((a) => a.id === 'mover'));
    Object.assign(logic, {
      id: 'ls-logic',
      name: 'Loader',
      props: { enabled: true, runInEditor: false },
      variables: [],
      graph: ${JSON.stringify(graphFor(firstId, 'ls-sound'))},
    });
    p.assets.push(logic, second, {
      id: 'ls-vars',
      type: 'variables',
      name: 'Run',
      props: { score: 0 },
      variables: ${JSON.stringify([variable('score', 'number', 0)])},
    }, {
      id: 'ls-sound',
      type: 'sound',
      name: 'Hum',
      props: { volume: 1, loop: true },
      file: ${JSON.stringify(file)},
    });`);
  await sleep(400);

  // 35b. Without a start scene the switch says the active scene – the two questions have the same
  //      answer until someone answers them differently.
  check(
    'with no start scene named, Play starts from the active one',
    (await json('__gm.state.project.startSceneId')) === '' &&
      (await playFrom()).mode === 'start' &&
      (await playFrom()).scene === firstName &&
      // The caption is the mode, worded like the menu entry it came from.
      (await playFrom()).label === 'Start scene',
    JSON.stringify(await playFrom()),
  );

  // 35c. Naming one: right-click the scene in the assets panel. By this point in the suite the
  //      project holds every kind of asset, so the new scene is the last row of a list far longer
  //      than the panel – selecting it brings it into view, which is what makes the click land.
  await evaluate("__gm.state.select({ kind: 'asset', assetId: 'ls-scene' })");
  await sleep(200);
  check(
    'selecting an asset scrolls its row into the panel',
    await has('Level 2'),
    JSON.stringify({ row: await json('__gm.assetRow("ls-scene")'), panel: await json('__gm.assetsRect()') }),
  );
  await clickText('Level 2', 'right');
  await sleep(250);
  await clickText('Set as start scene');
  await sleep(300);
  check(
    'the scene’s context menu names it the start scene, and the switch follows',
    (await json('__gm.state.project.startSceneId')) === 'ls-scene' && (await playFrom()).scene === 'Level 2',
    JSON.stringify(await playFrom()),
  );
  check(
    'the assets panel marks the start scene apart from the active one',
    await has('scene ▶'),
    JSON.stringify(
      await json('__gm.state.project.assets.filter((a) => a.type === "scene").map((a) => a.name)'),
    ),
  );
  await shot('35-start-scene');

  // 35d. Play starts there rather than in the scene the editor is showing.
  await play();
  const started = await playInfo();
  check(
    'Play runs the start scene while the editor still shows the active one',
    started.playing === true &&
      started.sceneId === 'ls-scene' &&
      (await json('__gm.state.project.activeSceneId')) === firstId,
    JSON.stringify(started),
  );

  // 35d². The scene selector keeps working while the run is on. It only moves the editor's view,
  //       which a double-click on a scene in the Assets panel has always done – disabling the one
  //       and not the other was the inconsistency. The run itself is untouched by it.
  const select = await json('__gm.sceneSelect()');
  await click(select.x, select.y);
  await sleep(250);
  const rows = await json('__gm.menuRows()');
  // The topmost hit, because the scene's name is on its row in the Assets panel as well.
  const entry = await locate('Level 2', true);
  await click(entry.x, entry.y);
  await sleep(300);
  const playing = await playInfo();
  check(
    'the scene selector stays usable in play mode, and the run runs on',
    select.enabled === true &&
      rows.some((row) => (row ?? '').includes('Level 2')) &&
      (await json('__gm.state.project.activeSceneId')) === 'ls-scene' &&
      playing.playing === true &&
      playing.sceneId === 'ls-scene',
    JSON.stringify({ select, rows, playing }),
  );

  // 35e. The swap itself. The score was counted in the old scene; a fresh run would show 0.
  const before = await waitFor(
    () => json('__gm.world()'),
    (w) => (w?.shared?.variables?.['ls-vars']?.score ?? 0) === 1,
  );
  const humming = await waitFor(stats, (s) => s.playing > 0);
  await press('g');
  const after = await waitFor(
    () => json('__gm.playInfo()'),
    (info) => info.sceneId === firstId,
  );
  const world = await json('__gm.world()');
  check(
    'Load scene swaps the running scene without ending the run',
    after.playing === true && after.sceneId === firstId,
    JSON.stringify({ before: before.shared?.variables, after }),
  );
  check(
    'the objects of the old scene are gone and the new scene is built',
    !world.entities.some((e) => e.objectId === 'ls-box') && world.entities.length > 0,
    JSON.stringify(world.entities.map((e) => e.name)),
  );
  check(
    'what belongs to the run carries over: the shared score survives the swap',
    world.shared?.variables?.['ls-vars']?.score === 1,
    JSON.stringify(world.shared?.variables),
  );
  check(
    'the sounds of the old scene end with the behaviors that were playing them',
    humming.playing >= 1 && (await stats()).playing === 0,
    JSON.stringify({ humming, now: await stats() }),
  );
  await stop();
  await sleep(300);

  // 35f. The switch is the way to run what you are working on instead – and it is remembered
  //      between runs, because it says how you work rather than what the game does.
  await openPlayFrom();
  await clickText('Active scene');
  await sleep(300);
  await play();
  const fromActive = await playInfo();
  check(
    'switched to "active scene", Play runs the scene the editor shows',
    fromActive.sceneId === firstId &&
      (await playFrom()).mode === 'active' &&
      (await playFrom()).label === 'Active scene' &&
      (await json('__gm.state.project.startSceneId')) === 'ls-scene',
    JSON.stringify({ fromActive, switch: await playFrom() }),
  );
  await stop();
  await sleep(300);
  await openPlayFrom();
  await clickText('Start scene');
  await sleep(300);
  check(
    'the switch goes back to the start scene',
    (await playFrom()).mode === 'start' && (await playFrom()).scene === 'Level 2',
    JSON.stringify(await playFrom()),
  );

  // 35g. Everything this step made goes again, the start scene included.
  await mutate(`
    const p = __gm.state.project;
    p.startSceneId = '';
    const gone = new Set(['ls-logic', 'ls-scene', 'ls-vars', 'ls-sound']);
    p.assets = p.assets.filter((a) => !gone.has(a.id));
    __gm.state.select(null);`);
  await sleep(300);
  check(
    'the step leaves nothing of its own behind',
    (await json('__gm.state.project.assets.filter((a) => a.id.startsWith("ls-")).length')) === 0 &&
      (await json('__gm.state.project.startSceneId')) === '' &&
      (await stats()).playing === 0,
    JSON.stringify(await json('__gm.state.project.assets.map((a) => a.id)')),
  );
}