// test/render/unitview.test.js — render/units.js UnitView and render/textures.js caches against a headless fake PIXI
// (test/render/fakepixi.js): tier chips (tokens have no tier), fallback-portrait allocation (no throw-away
// placeholder canvases, nothing built when the Spine model is already there), and the per-mount texture helpers
// (mountain silhouette, tier-chip redraw) that must not allocate a new canvas each time.

import { test, describe, before, after } from 'node:test';
import assert from 'node:assert/strict';
import { installFakePixi, fakeViewCtx } from './fakepixi.js';
import { presetCamera } from '../../public/js/render/projection.js';

let fake, UnitView, T;
before(async () => {
  fake = installFakePixi();
  ({ UnitView } = await import('../../public/js/render/units.js'));
  T = await import('../../public/js/render/textures.js');
});
after(() => fake.restore());

const tick = () => new Promise((r) => setImmediate(r));
const cam = () => presetCamera('prep', { width: 1280, height: 720 });
const diamonds = () => fake.canvases.filter((c) => c.width === 160 && c.height === 160);

/** Asset store stub: avatar image + (optionally) a Spine model, both resolved asynchronously. */
function store({ image = true, spine = false, imageDelay = 0 } = {}) {
  const img = { width: 180, height: 180 };
  const entry = { skel: '/s/x.skel', atlas: '/s/x.atlas', textures: ['/s/x.png'], anims: { idle: 'Idle' }, animations: { Idle: 1 } };
  return {
    picture: (id) => (id ? `/pic/${id}.png` : null),
    image: (u) => new Promise((r) => (imageDelay ? setTimeout(() => r(image ? img : null), imageDelay) : r(image ? img : null))),
    spineEntry: () => (spine ? entry : null),
    spine: { acquire: async () => ({ animations: [{ name: 'Idle' }] }), release() {} },
  };
}

function view(info, opts = {}, assets = store()) {
  const ctx = fakeViewCtx(fake.P, { assets, cam: cam });
  return new UnitView(ctx, { id: 1, side: 'ally', kind: 'chess', defId: 'char_x', tier: 3, x: 5, y: 12, maxHp: 1000, ...info }, opts);
}

describe('tier chips', () => {
  test('summon tokens in the hand show no tier chip (tokens have no tier)', async () => {
    const v = view({ kind: 'token', defId: 'token_10028_vigil_wolf', avatar: 'token_10028_vigil_wolf' }, { prep: true });
    for (let i = 0; i < 3; i++) v.update(1 / 60, cam(), i / 60);
    assert.ok(!v.chip || !v.chip.visible, 'no chip on a token');
  });

  test('operators keep their chip in prep and in battle; enemies never have one', () => {
    const p = view({ kind: 'chess', tier: 4 }, { prep: true });
    p.update(1 / 60, cam(), 0);
    assert.ok(p.chip && p.chip.visible);
    const b = view({ kind: 'chess', tier: 2 });
    b.update(1 / 60, cam(), 0);
    assert.ok(b.chip && b.chip.visible);
    const e = view({ side: 'enemy', kind: 'enemy', defId: 'enemy_1007_slime' });
    e.update(1 / 60, cam(), 0);
    assert.equal(e.chip, null);
  });
});

describe('fallback portraits (avatar diamonds)', () => {
  test('an avatar that loads builds one diamond — no image-less placeholder first', async () => {
    const before = diamonds().length;
    const v = view({ defId: 'char_a', avatar: 'char_a' });
    v.update(1 / 60, cam(), 0);
    await tick(); await tick();
    v.update(1 / 60, cam(), 1 / 60);
    assert.equal(diamonds().length - before, 1, 'one 160×160 canvas');
    assert.notEqual(v.fallback.texture, fake.P.Texture.EMPTY, 'the diamond shows');
  });

  test('a unit whose Spine model is ready before its first frame builds no diamond at all', async () => {
    const before = diamonds().length;
    const v = view({ defId: 'char_b', avatar: 'char_b' }, {}, store({ spine: true }));
    await tick(); await tick();
    assert.ok(v.spineReady, 'spine ready');
    for (let i = 0; i < 30; i++) v.update(1 / 60, cam(), i / 60);
    assert.equal(diamonds().length - before, 0);
  });

  test('a missing avatar falls back to the procedural placeholder (once)', async () => {
    const before = diamonds().length;
    const v = view({ defId: 'char_c', avatar: 'char_c' }, {}, store({ image: false }));
    await tick(); await tick();
    for (let i = 0; i < 3; i++) v.update(1 / 60, cam(), i / 60);
    assert.equal(diamonds().length - before, 1);
    assert.notEqual(v.fallback.texture, fake.P.Texture.EMPTY);
  });

  test('a slow avatar shows the placeholder meanwhile, then the picture', async () => {
    const before = diamonds().length;
    let release;
    const gate = new Promise((r) => { release = r; });
    const assets = { ...store(), image: () => gate };
    const v = view({ defId: 'char_d', avatar: 'char_d' }, {}, assets);
    v.update(1 / 60, cam(), 0);
    assert.equal(diamonds().length - before, 0, 'nothing built while the avatar may still arrive quickly');
    const t0 = Date.now();
    while (v.fallback.texture === fake.P.Texture.EMPTY && Date.now() - t0 < 5000) { await new Promise((r) => setTimeout(r, 40)); v.update(1 / 60, cam(), 0); }
    assert.ok(Date.now() - t0 >= 300, 'placeholder only after the wait');
    assert.notEqual(v.fallback.texture, fake.P.Texture.EMPTY, 'placeholder while waiting');
    release({ width: 180, height: 180 });
    await tick(); await tick();
    v.update(1 / 60, cam(), 0);
    assert.equal(diamonds().length - before, 2, 'placeholder + picture');
  });

  test('two views of the same unit share the cached diamond', async () => {
    const a = view({ defId: 'char_e', avatar: 'char_e' });
    a.update(1 / 60, cam(), 0);
    await tick(); await tick();
    a.update(1 / 60, cam(), 0);
    const before = diamonds().length;
    const b = view({ defId: 'char_e', avatar: 'char_e' });
    b.update(1 / 60, cam(), 0);
    await tick(); await tick();
    b.update(1 / 60, cam(), 0);
    assert.equal(diamonds().length, before);
    assert.equal(a.fallback.texture, b.fallback.texture);
  });
});

describe('diamond cache', () => {
  test('bounded LRU; eviction never destroys a texture a view may still show', () => {
    const first = T.diamondTexture('lru_0', null, 0xffffff);
    for (let i = 1; i < 400; i++) {
      T.diamondTexture(`lru_${i}`, null, 0xffffff);
      if (i % 50 === 0) assert.equal(T.diamondTexture('lru_0', null, 0xffffff), first, 'recently used stays cached');
    }
    assert.ok(!first.destroyed && !first.baseTexture.destroyed);
    const n0 = diamonds().length;
    T.diamondTexture('lru_1', null, 0xffffff);
    assert.equal(diamonds().length, n0 + 1, 'the least recently used ones were evicted');
  });
});

describe('per-mount textures', () => {
  test('silhouetteTexture is cached per image (the field view builds it on every mount)', () => {
    const img = { width: 1024, height: 236 };
    const n0 = fake.canvases.length;
    const t1 = T.silhouetteTexture(img);
    const t2 = T.silhouetteTexture(img);
    assert.equal(t1, t2);
    assert.equal(fake.canvases.length - n0, 1);
    assert.notEqual(T.silhouetteTexture({ width: 512, height: 100 }), t1);
  });

  test('refreshTierChips redraws the chip atlas in place (no new canvas, chips handed out stay valid)', () => {
    const chip = T.tierChip(3, false);
    const n0 = fake.canvases.length;
    const b0 = fake.baseTextures.length;
    for (let i = 0; i < 5; i++) T.refreshTierChips();
    const again = T.tierChip(3, false);
    assert.equal(fake.canvases.length, n0, 'no new canvas');
    assert.equal(fake.baseTextures.length, b0, 'no new base texture');
    assert.equal(again.baseTexture, chip.baseTexture);
    assert.ok(!chip.destroyed && !chip.baseTexture.destroyed);
  });
});

describe('field view teardown (app.js releaseGl)', () => {
  test('drops the dead renderer’s GL copies of shared textures, buffers, geometries and cached programs', async () => {
    const { releaseGl } = await import('../../public/js/render/app.js');
    const UID = 7;
    const listeners = [];
    const mkBt = () => ({ _glTextures: { [UID]: { texture: {} }, 3: { texture: {} } } });
    const shared = [mkBt(), mkBt()];
    const deleted = [];
    const ts = {
      managedTextures: shared.slice(),
      destroyTexture(bt, skipRemove) {
        deleted.push(bt);
        delete bt._glTextures[UID];
        listeners.push('off');
        if (!skipRemove) this.managedTextures.splice(this.managedTextures.indexOf(bt), 1);
      },
    };
    const disposed = [];
    const sys = (name) => ({ disposeAll(lost) { disposed.push([name, lost]); } });
    const prog = { glPrograms: { [UID]: { program: 'p7' }, 3: { program: 'p3' } } };
    const gl = { deleted: [], deleteProgram(p) { this.deleted.push(p); } };
    const prevPixi = globalThis.PIXI;
    globalThis.PIXI = { ...prevPixi, utils: { ...(prevPixi?.utils || {}), ProgramCache: { src: prog } } };
    try {
      releaseGl({ CONTEXT_UID: UID, gl, texture: ts, geometry: sys('geometry'), buffer: sys('buffer'), framebuffer: sys('framebuffer') });
    } finally { globalThis.PIXI = prevPixi; }
    assert.deepEqual(deleted, shared);
    assert.equal(ts.managedTextures.length, 0);
    for (const bt of shared) assert.deepEqual(Object.keys(bt._glTextures), ['3'], 'other contexts untouched');
    assert.deepEqual(disposed.map((d) => d[0]).sort(), ['buffer', 'framebuffer', 'geometry']);
    assert.ok(disposed.every((d) => d[1] === false));
    assert.deepEqual(Object.keys(prog.glPrograms), ['3']);
    assert.deepEqual(gl.deleted, ['p7']);
    assert.doesNotThrow(() => releaseGl(null));
    assert.doesNotThrow(() => releaseGl({}));
  });
});

describe('enemy preview pen figures (lod idle)', () => {
  /** A UnitView of a pen figure with a Spine model, an impostor atlas (full or not) and a counting renderer. */
  async function penFigure(full) {
    let frame = 0;
    const renders = [];
    const atlas = {
      alloc: (w, h) => (full ? null : { w, h, tex: new fake.P.Texture(), clip: false }),
      free() {}, park(o) { o.visible = false; }, unpark(o) { o.visible = true; }, draw() {},
    };
    const ctx = fakeViewCtx(fake.P, {
      assets: store({ spine: true }), cam, frameNo: () => frame, impostors: atlas,
      renderer: { resolution: 1, render: (obj, o) => renders.push(o?.renderTexture || null) },
    });
    const v = new UnitView(ctx, { id: 'e:0', side: 'enemy', kind: 'enemy', defId: 'enemy_1007_slime', tier: 1, x: 9, y: 15, maxHp: 1, facing: -1 }, { prep: true, lod: 'idle' });
    await tick(); await tick();
    assert.ok(v.spineReady, 'spine ready');
    let steps = 0;
    const upd = v.actor.update.bind(v.actor);
    v.actor.update = (dt) => { steps++; return upd(dt); };
    const step = () => { v.update(1 / 60, cam(), frame / 60); frame++; };
    return { v, step, renders, steps: () => steps };
  }

  test('with room in the shared atlas: an impostor refreshed every 3rd frame, never a private render target', async () => {
    const { v, step, renders, steps } = await penFigure(false);
    for (let i = 0; i < 30; i++) step();
    assert.ok(v.imp && v.imp.slot, 'atlas slot');
    assert.equal(renders.length, 0, 'drawn by the atlas flush, no per-figure render call');
    assert.ok(steps() <= 12, `idle loop stepped ≈ every 3rd frame (${steps()} of 30)`);
  });
});