import { colourDistance } from '../lib/harness.mjs';
import { edge, node, propertiesOf, variable, written } from '../lib/builders.mjs';
import { MAKE_OBJECT, openTab } from './lib/scaffold.mjs';

/**
 * Animations: made from a texture, edited in their own tab, worn by a sprite through `texture`,
 * run in play only, and heard by `On animation finished`. The step pastes a strip of four colour
 * cells, so which frame is on screen is a `pixelAt` question. It removes everything it made.
 */

const CELLS = ['#e63c3c', '#3cc85a', '#466ef0', '#f5f5f5'];
const NAMES = ['red', 'green', 'blue', 'white'];

const PASTE_STRIP = `(async () => {
  const canvas = document.createElement('canvas');
  canvas.width = 64;
  canvas.height = 16;
  const g = canvas.getContext('2d');
  ${JSON.stringify(CELLS)}.forEach((colour, i) => { g.fillStyle = colour; g.fillRect(i * 16, 0, 16, 16); });
  const blob = await new Promise((resolve) => canvas.toBlob(resolve, 'image/png'));
  const transfer = new DataTransfer();
  transfer.items.add(new File([blob], 'strip.png', { type: 'image/png' }));
  window.dispatchEvent(new ClipboardEvent('paste', { clipboardData: transfer, bubbles: true }));
})()`;

const FRAME_IDS = ['an-f0', 'an-f1', 'an-f2', 'an-f3'];

function nearestCell(sample) {
  let best = -1;
  let bestDistance = Infinity;
  CELLS.forEach((hex, i) => {
    const distance = colourDistance(sample, hex);
    if (distance < bestDistance) {
      bestDistance = distance;
      best = i;
    }
  });
  return bestDistance < 60 ? NAMES[best] : `other ${sample}`;
}

/** `On animation finished (walk) → done += 1, and the owner wears Run`. */
const logicGraph = (walkId) => ({
  nodes: [
    node('an-done', 'OnAnimationFinished', 0, 0, { animation: walkId }),
    node('an-count', 'Variables', 300, 0, {}, [written('done', 'number')]),
    node('an-add', 'Add', 300, 200, { b: 1 }),
    node('an-owner', 'Owner', 300, 360),
    node('an-wear', 'Properties', 600, 0, { ...propertiesOf('sprite'), texture: 'an-run' }, [
      written('texture', 'texture'),
    ]),
  ],
  edges: [
    edge('an-e1', 'an-done', 'exec', 'an-count', 'exec'),
    edge('an-e2', 'an-count', 'done', 'an-add', 'a'),
    edge('an-e3', 'an-add', 'result', 'an-count', 'done'),
    edge('an-e4', 'an-count', 'exec', 'an-wear', 'exec'),
    edge('an-e5', 'an-owner', 'object', 'an-wear', 'object'),
  ],
});

export async function animation(t) {
  const { check, sleep, json, evaluate, shot, mutate, press, click, clickText, drag, undo, redo, showTab } =
    t;
  const { mouse, typeText } = t;
  const { entity, stop } = t;
  const info = () => json('__gm.animation.current()');
  const frames = async (id) =>
    await json(`__gm.state.project.assets.find((a) => a.id === ${JSON.stringify(id)})?.frames ?? null`);
  const previewColour = async () => {
    const rect = (await info()).preview;
    return rect
      ? nearestCell(
          await json(`__gm.pixelAt(${Math.round(rect.x + rect.w / 2)}, ${Math.round(rect.y + rect.h / 2)})`),
        )
      : 'none';
  };

  await press('Escape');
  await evaluate('document.activeElement instanceof HTMLElement && document.activeElement.blur()');
  await evaluate('__gm.state.select(null)');

  // 25a. A strip of four cells, cut into four frames and moved to the head of the asset list.
  await evaluate(PASTE_STRIP);
  await sleep(2500);
  const strip = await json(
    "(__gm.state.project.assets.find((a) => a.type === 'texture' && a.name === 'strip') ?? {}).id ?? ''",
  );
  check('the strip is imported as a texture', strip !== '', strip);
  await mutate(`
    const p = __gm.state.project;
    const index = p.assets.findIndex((a) => a.id === ${JSON.stringify(strip)});
    const texture = p.assets.splice(index, 1)[0];
    texture.props.filter = 'nearest';
    texture.frames = ${JSON.stringify(FRAME_IDS)}.map((id, i) => ({ id, name: 'Cell ' + (i + 1), x: i * 16, y: 0, w: 16, h: 16 }));
    p.assets.unshift(texture);
  `);

  // 25b. The texture's context menu makes an animation of its frames, as one undo step.
  const row = await json(`__gm.assetRow(${JSON.stringify(strip)})`);
  await click(row.x, row.y, 'right');
  await clickText('Create animation from texture');
  const made = await json(
    "__gm.state.project.assets.filter((a) => a.type === 'animation').map((a) => ({ id: a.id, name: a.name, frames: a.frames, props: a.props }))",
  );
  const walk = made[0] ?? {};
  check(
    'Create animation from texture plays its frames in order',
    made.length === 1 && JSON.stringify(walk.frames) === JSON.stringify(FRAME_IDS),
    JSON.stringify(made),
  );
  check(
    'and is selected, named after the texture, at 10 fps looping',
    (await json('__gm.state.selection?.assetId')) === walk.id &&
      walk.name === 'strip 2' &&
      walk.props?.fps === 10 &&
      walk.props?.playback === 'loop',
    JSON.stringify({ selection: await json('__gm.state.selection'), walk }),
  );
  await undo();
  const undone = await json("__gm.state.project.assets.filter((a) => a.type === 'animation').length");
  await redo();
  check(
    'undo takes asset and frames back in one step, redo brings both',
    undone === 0 && JSON.stringify(await frames(walk.id)) === JSON.stringify(FRAME_IDS),
    JSON.stringify({ undone, after: await frames(walk.id) }),
  );

  // 25c. The Animation tab shows it and plays it; the inspector keeps its two properties.
  await evaluate(`__gm.state.select({ kind: 'asset', assetId: ${JSON.stringify(walk.id)} })`);
  await openTab(t, 'animation');
  check(
    'the inspector edits frames per second and playback',
    (await t.has('Frames per second')) && (await t.has('Playback')) && (await t.has('Loop')),
  );
  const opened = await info();
  check(
    'the tab button has room for its bold label',
    (await json("__gm.shownLabel('Animation')")) === 'Animation',
    String(await json("__gm.shownLabel('Animation')")),
  );
  check(
    'the Animation tab shows the selected animation with its four frames, playing',
    (await json('__gm.tab()')) === 'animation' &&
      opened.assetId === walk.id &&
      opened.frames === 4 &&
      opened.playing,
    JSON.stringify(opened),
  );
  const shown = new Set();
  for (let i = 0; i < 8; i++) {
    shown.add((await info()).shown);
    await sleep(70);
  }
  check('the preview runs through the frames', shown.size >= 3, JSON.stringify([...shown]));
  await shot('01-playing');

  // 25c-ii. (#90) The preview runs on the global clock like everything else that moves by itself,
  //         so a scale of 0 holds the frame on screen while the preview is still *playing*.
  await evaluate('__gm.setTimeScale(0)');
  await sleep(300);
  const atZero = await info();
  await sleep(500);
  const stillZero = await info();
  await evaluate('__gm.setTimeScale(1)');
  const moved = new Set();
  for (let i = 0; i < 8; i++) {
    moved.add((await info()).shown);
    await sleep(70);
  }
  check(
    'a global time scale of 0 holds the frame without stopping the play, and 1 runs it on',
    atZero.playing === true &&
      stillZero.playing === true &&
      stillZero.shown === atZero.shown &&
      moved.size >= 3,
    JSON.stringify({ atZero: atZero.shown, stillZero: stillZero.shown, afterwards: [...moved] }),
  );

  // 25d. Pausing holds the frame on screen, and the preview shows that frame's picture.
  await click(...Object.values(await json('__gm.animation.playButton()')));
  const paused = await info();
  await sleep(350);
  check(
    'the play button pauses, and the frame on screen stays',
    !paused.playing &&
      (await json('__gm.animation.playLabel()')) === '▶' &&
      (await info()).shown === paused.shown,
    JSON.stringify({ paused, later: await info() }),
  );
  check(
    'the preview draws the frame it says it shows',
    (await previewColour()) === NAMES[paused.shown],
    JSON.stringify({ shown: paused.shown, colour: await previewColour() }),
  );

  // 25e. A click on a tile selects it and shows it.
  const tile = async (i) => json(`__gm.animation.tileCentre(${i})`);
  const third = await tile(2);
  await click(third.x, third.y);
  const picked = await info();
  check(
    'clicking a tile selects it and the preview shows it',
    picked.selected === 2 && picked.shown === 2 && (await previewColour()) === 'blue',
    JSON.stringify({ picked, colour: await previewColour() }),
  );
  await shot('02-tile-picked');

  // 25e'. The wheel zooms the preview about the pointer, the middle button pans, Fit undoes both.
  const fitted = picked.preview;
  const pointer = { x: Math.round(fitted.x + fitted.w * 0.25), y: Math.round(fitted.y + fitted.h * 0.5) };
  const wheel = async (x, y, deltaY) => {
    await mouse('mouseMoved', x, y);
    await mouse('mouseWheel', x, y, 'none', { deltaX: 0, deltaY });
    await sleep(250);
  };
  await wheel(pointer.x, pointer.y, -240);
  const zoomed = (await info()).preview;
  const share = (rect) => ((pointer.x - rect.x) / rect.w).toFixed(3);
  check(
    'the wheel zooms the preview in about the pointer',
    zoomed.w > fitted.w * 1.3 && share(zoomed) === share(fitted),
    JSON.stringify({ fitted, zoomed }),
  );
  check(
    'the pixel under the pointer is still the frame shown',
    nearestCell(await json(`__gm.pixelAt(${pointer.x}, ${pointer.y})`)) === 'blue',
  );
  await drag(pointer.x, pointer.y, pointer.x + 40, pointer.y - 30, { button: 'middle' });
  const panned = (await info()).preview;
  check(
    'the middle button pans it',
    Math.round(panned.x - zoomed.x) === 40 &&
      Math.round(panned.y - zoomed.y) === -30 &&
      panned.w === zoomed.w,
    JSON.stringify({ zoomed, panned }),
  );
  await wheel(third.x, third.y, -240);
  check(
    'the wheel over the strip leaves the zoom alone',
    JSON.stringify((await info()).preview) === JSON.stringify(panned),
    JSON.stringify((await info()).preview),
  );
  await shot('02b-zoomed');
  await clickText('Fit');
  check(
    'Fit puts the preview back',
    JSON.stringify((await info()).preview) === JSON.stringify(fitted),
    JSON.stringify((await info()).preview),
  );

  // 25f. Dragging a tile into another gap reorders the frames, as one undo step.
  const first = await tile(0);
  await drag(first.x, first.y, third.x + 39, third.y, 10);
  const reordered = await frames(walk.id);
  check(
    'dragging the first tile behind the third moves that frame there',
    JSON.stringify(reordered) === JSON.stringify(['an-f1', 'an-f2', 'an-f0', 'an-f3']) &&
      (await info()).selected === 2,
    JSON.stringify({ reordered, info: await info() }),
  );
  await undo();
  check('undo puts it back', JSON.stringify(await frames(walk.id)) === JSON.stringify(FRAME_IDS));

  // 25g. Delete removes the selected tile.
  const second = await tile(1);
  await click(second.x, second.y);
  await press('Delete');
  const deleted = await frames(walk.id);
  check(
    'Delete removes the selected frame and nothing else',
    JSON.stringify(deleted) === JSON.stringify(['an-f0', 'an-f2', 'an-f3']) &&
      (await json(`__gm.state.project.assets.some((a) => a.id === ${JSON.stringify(walk.id)})`)),
    JSON.stringify(deleted),
  );
  await undo();

  // 25h. + Frames offers a sheet's frames at once and inserts them after the selection.
  await clickText('+ Frames');
  // Search first: in the full suite a 17-frame sheet sorts ahead of this one and pushes the later
  // cells out of the list's view, and a row outside its list is not on the screen to be read.
  // The filter also sharpens the check, because the animation is called "strip 2" and would match.
  await typeText('strip');
  const offered = await json('__gm.overlayTexts()');
  check(
    '+ Frames offers the whole strip and each cell, but no animation',
    offered.includes('strip – all 4 frames') &&
      offered.includes('strip / Cell 3') &&
      offered.includes('strip / Cell 4') &&
      !offered.some((s) => s.startsWith('strip 2')),
    JSON.stringify(offered),
  );
  await clickText('strip – all 4 frames');
  const grown = await frames(walk.id);
  check(
    'all four go in right after the selected frame',
    JSON.stringify(grown) === JSON.stringify(['an-f0', 'an-f1', ...FRAME_IDS, 'an-f2', 'an-f3']),
    JSON.stringify(grown),
  );
  await undo();

  // 25i. A sprite wears the animation through its Texture picker.
  await mutate(`
    const p = __gm.state.project;
    const sprite = structuredClone(p.assets.find((a) => a.type === 'sprite'));
    Object.assign(sprite, { id: 'an-sprite', name: 'Animated' });
    sprite.props = { ...sprite.props, width: 80, height: 80, color: 0xffffff, texture: '' };
    p.assets.unshift(sprite);
    const scene = __gm.state.activeScene;
    ${MAKE_OBJECT}
    const box = make('an-box', 'an-sprite', '', 120, 'Animated');
    box.position.z = 950;
    scene.objects.push(box);
    __gm.state.select({ kind: 'asset', assetId: 'an-sprite' });
  `);
  await sleep(500);
  const picker = await json("__gm.inspectorField('Texture', true)");
  await click(picker.x, picker.y);
  const choices = await json('__gm.overlayTexts()');
  check(
    'the Texture picker offers the animation first, marked as one',
    choices.indexOf('strip 2 (animation)') === choices.indexOf('● None') + 1,
    JSON.stringify(choices),
  );
  await clickText('strip 2 (animation)');
  check(
    'picking it makes the sprite wear the animation',
    (await json("__gm.state.project.assets.find((a) => a.id === 'an-sprite').props.texture")) === walk.id,
  );

  // 25j. The scene shows the first frame and does not play.
  await showTab('scene');
  await sleep(700);
  const box = await json("__gm.objectRect('an-box')");
  const sceneColour = async () =>
    nearestCell(await json(`__gm.pixelAt(${Math.round(box.x)}, ${Math.round(box.y)})`));
  const before = await sceneColour();
  await sleep(450);
  check(
    'the Scene tab shows the first frame and stays on it',
    before === 'red' && (await sceneColour()) === 'red',
    JSON.stringify({ box, before, after: await sceneColour() }),
  );
  await shot('03-scene-first-frame');

  // 25j'. A frame is a texture of its own. Drawn from the sheet, an edge that landed inside a screen
  //       pixel showed the neighbouring cell: the partly covered pixel is evaluated at its centre,
  //       past the edge. Measured in play, where the background is flat.
  await mutate(`__gm.state.project.assets.find((a) => a.id === 'an-sprite').props.texture = 'an-f1'`);
  const rgb = (hex) => [1, 3, 5].map((i) => parseInt(hex.slice(i, i + 2), 16));
  const fraction = (v) => v - Math.floor(v);
  const edgesOf = async () => {
    const r = await json("__gm.gameRect('an-box')");
    return { y: Math.round(r.y), left: r.x - r.w / 2, right: r.x + r.w / 2, scale: r.w / 80 };
  };
  // Moves the box so the edge's fraction lands where the pixel is partly covered but its centre
  // lies outside; `outward` says which way the neighbouring cell would be.
  const edgePixels = async (side, target, outward) => {
    await t.play();
    const first = await edgesOf();
    await stop();
    const shift = (target - fraction(first[side]) + 1) % 1;
    await mutate(
      `__gm.state.activeScene.objects.find((o) => o.id === 'an-box').position.x += ${shift / first.scale}`,
    );
    await t.play();
    const e = await edgesOf();
    const x = Math.floor(e[side]);
    const edge = rgb(await json(`__gm.pixelAt(${x}, ${e.y})`));
    const outside = rgb(await json(`__gm.pixelAt(${x + outward * 2}, ${e.y})`));
    await stop();
    return { fraction: fraction(e[side]).toFixed(2), edge, outside };
  };
  // The edge pixel is the cell's green over the background and nothing else: red and blue rise
  // above the background only in the cell's own proportion to the rise in green (plus rounding),
  // and green rises enough to prove it is the partly covered pixel, not plain background.
  const cell = rgb(CELLS[1]);
  const onlyOwnColour = ({ edge, outside }) => {
    const green = edge[1] - outside[1];
    return (
      green > 10 &&
      [0, 2].every(
        (c) => edge[c] - outside[c] <= (green * (cell[c] - outside[c])) / (cell[1] - outside[1]) + 3,
      )
    );
  };
  const leftEdge = await edgePixels('left', 0.75, -1);
  check(
    'the left edge of a frame shows nothing of the cell to its left',
    onlyOwnColour(leftEdge),
    JSON.stringify(leftEdge),
  );
  const rightEdge = await edgePixels('right', 0.25, 1);
  check(
    'nor the right edge anything of the cell to its right',
    onlyOwnColour(rightEdge),
    JSON.stringify(rightEdge),
  );
  await mutate(
    `__gm.state.project.assets.find((a) => a.id === 'an-sprite').props.texture = ${JSON.stringify(walk.id)}`,
  );

  // 25k. Play runs it: the pixels the game draws change colour over time.
  await t.play();
  const colours = new Set();
  for (let i = 0; i < 10; i++) {
    const at = await json("__gm.gameScreen('an-box')");
    if (at) colours.add(nearestCell(await json(`__gm.pixelAt(${Math.round(at.x)}, ${Math.round(at.y)})`)));
    await sleep(60);
  }
  const clock = (await entity('an-box'))?.animation;
  await shot('04-playing');
  await stop();
  check(
    'in play the sprite runs through the frames',
    [...colours].filter((c) => NAMES.includes(c)).length >= 3 && clock?.id === walk.id && clock.time > 0,
    JSON.stringify({ colours: [...colours], clock }),
  );

  // 25l. Once: the end is an event, and a Properties node puts another animation on.
  await mutate(`
    const p = __gm.state.project;
    p.assets.find((a) => a.id === ${JSON.stringify(walk.id)}).props.playback = 'once';
    p.assets.unshift({ id: 'an-run', type: 'animation', name: 'Run', props: { fps: 10, playback: 'loop' }, frames: ['an-f3'] });
    const logic = structuredClone(p.assets.find((a) => a.id === 'mover'));
    Object.assign(logic, {
      id: 'an-logic',
      name: 'Animation logic',
      props: { enabled: true, runInEditor: false, done: 0 },
      variables: ${JSON.stringify([variable('done', 'number', 0)])},
      graph: ${JSON.stringify(logicGraph(walk.id))},
    });
    p.assets.unshift(logic);
    const scene = __gm.state.activeScene;
    ${MAKE_OBJECT}
    scene.objects.push(make('an-brain', 'an-logic', 'an-box', 0, 'Animation logic'));
    __gm.state.select(null);
  `);
  await t.play();
  await sleep(900);
  const brain = (await entity('an-brain'))?.props;
  const worn = await entity('an-box');
  const at = await json("__gm.gameScreen('an-box')");
  const after = at
    ? nearestCell(await json(`__gm.pixelAt(${Math.round(at.x)}, ${Math.round(at.y)})`))
    : 'none';
  await stop();
  check(
    'On animation finished fires once when a once animation ends',
    brain?.done === 1,
    JSON.stringify({ brain, log: await json('__gm.state.notice') }),
  );
  check(
    'and the Properties node it runs puts the other animation on',
    worn?.props.texture === 'an-run' && worn?.animation?.id === 'an-run' && after === 'white',
    JSON.stringify({ texture: worn?.props.texture, clock: worn?.animation, after }),
  );

  // 25l'. A picture is a kind of its own: the Texture node hands one into the graph, and a
  //       variable may be one. Both are picked, never typed.
  const pickPicture = async (label, name) => {
    const field = await json(`__gm.inspectorField(${JSON.stringify(label)}, true)`);
    await click(field.x, field.y);
    await typeText(name);
    await press('Enter');
  };
  await mutate(`
    const logic = __gm.state.project.assets.find((a) => a.id === 'an-logic');
    logic.graph.nodes.push(${JSON.stringify(node('an-pic', 'Texture', 600, 300))});
    logic.variables.push(${JSON.stringify(variable('pic', 'texture', ''))});
    logic.props.pic = '';
    __gm.state.select({ kind: 'node', assetId: 'an-logic', nodeId: 'an-pic', nodeIds: ['an-pic'] });
  `);
  await pickPicture('Value', walk.name);
  const picNode = (await t.asset('an-logic')).graph.nodes.find((n) => n.id === 'an-pic');
  const picRows = (await json("__gm.graph.nodeSettings('an-pic')")) ?? [];
  check(
    'the Texture node picks its picture and shows it by name',
    picNode?.params.value === walk.id && picRows.some((r) => r.includes(walk.name)),
    JSON.stringify({ params: picNode?.params, rows: picRows }),
  );
  await evaluate("__gm.state.select({ kind: 'asset', assetId: 'an-logic' })");
  await pickPicture('pic', walk.name);
  check(
    'a texture variable is picked with the same picker',
    (await t.asset('an-logic')).props.pic === walk.id,
    JSON.stringify((await t.asset('an-logic')).props),
  );
  await shot('04b-texture-kind');

  // 25m. Deleting the texture counts the animations that play its frames.
  const again = await json(`__gm.assetRow(${JSON.stringify(strip)})`);
  await click(again.x, again.y, 'right');
  await clickText('Delete…');
  const dialog = await json('__gm.overlayTexts()');
  await shot('05-delete-dialog');
  check(
    'deleting the texture names the animations that use it',
    dialog.some((s) => s.includes('2 animation(s)')),
    JSON.stringify(dialog),
  );
  check('and its bold Delete button is not cut short', dialog.includes('Delete'), JSON.stringify(dialog));
  const cancel = await t.locate('Cancel', true);
  await click(cancel.x, cancel.y);

  await mutate(`
    const p = __gm.state.project;
    const mine = new Set(['an-sprite', 'an-run', 'an-logic', ${JSON.stringify(walk.id)}, ${JSON.stringify(strip)}]);
    p.assets = p.assets.filter((a) => !mine.has(a.id));
    const scene = __gm.state.activeScene;
    scene.objects = scene.objects.filter((o) => o.id !== 'an-box' && o.id !== 'an-brain');
    __gm.state.select(null);
    __gm.state.preview();
  `);
  const left = await json(
    "__gm.state.project.assets.filter((a) => a.type === 'animation' || a.id === 'an-sprite' || a.id === 'an-logic').length",
  );
  check('the step leaves the fixture as it found it', left === 0, String(left));
}