import assert from 'node:assert/strict';
import { readFileSync } from 'node:fs';
import { dirname, join } from 'node:path';
import { fileURLToPath } from 'node:url';
import { test, beforeEach, afterEach } from 'node:test';
import { get } from 'svelte/store';
import type { Draft, Mask, MaskParams, WorkerIn, WorkerOut } from './capture.types';
import { createCaptureSession, type DraftStore } from './session';

const here = dirname(fileURLToPath(import.meta.url));

function tinyJpeg(label: string): File {
  const bytes = new Uint8Array([0xff, 0xd8, 0xff, 0xe0, label.charCodeAt(0) & 0xff]);
  return new File([bytes], `${label}.jpg`, { type: 'image/jpeg' });
}

function memStore(): DraftStore & { peek: () => Draft | null } {
  let mem: Draft | null = null;
  return {
    loadDraft: async () => mem,
    saveDraft: async (d) => {
      mem = d;
    },
    clearDraft: async () => {
      mem = null;
    },
    peek: () => mem,
  };
}

let store: ReturnType<typeof memStore>;

beforeEach(() => {
  store = memStore();
});

type MaskBehavior = {
  w: number;
  h: number;
  slabPx: number;
  slabBounds?: { x: number; y: number; w: number; h: number };
};

class FakeMaskWorker {
  onmessage: ((ev: MessageEvent<WorkerOut>) => void) | null = null;
  static inits: Blob[] = [];
  static maskCalls: { sheet: string; sensitivity: number; blob: Blob | null }[] = [];
  static lastInitBlob: Blob | null = null;
  static behaviorFor: (blob: Blob) => MaskBehavior = () => ({
    w: 1000,
    h: 900,
    slabPx: 1000 * 900,
    slabBounds: { x: 0, y: 0, w: 1000, h: 900 },
  });

  constructor(_url: URL | string, _opts?: WorkerOptions) {}

  postMessage(msg: WorkerIn) {
    if (msg.kind === 'init') {
      FakeMaskWorker.inits.push(msg.blob);
      FakeMaskWorker.lastInitBlob = msg.blob;
      const id = msg.id;
      const b = FakeMaskWorker.behaviorFor(msg.blob);
      queueMicrotask(() => {
        this.onmessage?.({ data: { id, kind: 'decoded', w: b.w, h: b.h } } as MessageEvent<WorkerOut>);
      });
      return;
    }
    if (msg.kind === 'mask') {
      const id = msg.id;
      const blob = FakeMaskWorker.lastInitBlob;
      FakeMaskWorker.maskCalls.push({
        sheet: msg.sheet,
        sensitivity: msg.sensitivity,
        blob,
      });
      const b = blob ? FakeMaskWorker.behaviorFor(blob) : { w: 40, h: 20, slabPx: 0 };
      const bitset = new Uint8Array(Math.max(1, b.w * b.h)).fill(b.slabPx > 0 ? 1 : 0);
      const bbox = {
        corners: [
          [b.w, 0],
          [b.w, b.h],
          [0, b.h],
          [0, 0],
        ] as [number, number][],
        longSidePx: b.w,
        angleDeg: 0,
      };
      const slabBounds = b.slabBounds ?? { x: 0, y: 0, w: b.w, h: b.h };
      queueMicrotask(() => {
        this.onmessage?.({
          data: {
            id,
            kind: 'ready',
            slabPx: b.slabPx,
            bitset,
            bbox,
            slabBounds,
          },
        } as MessageEvent<WorkerOut>);
      });
      return;
    }
  }

  terminate() {}
}

const RealWorker = globalThis.Worker;
const RealCreateImageBitmap = globalThis.createImageBitmap;

function installFakes() {
  FakeMaskWorker.inits = [];
  FakeMaskWorker.maskCalls = [];
  FakeMaskWorker.lastInitBlob = null;
  FakeMaskWorker.behaviorFor = () => ({
    w: 1000,
    h: 900,
    slabPx: 1000 * 900,
    slabBounds: { x: 0, y: 0, w: 1000, h: 900 },
  });
  (globalThis as unknown as { Worker: typeof FakeMaskWorker }).Worker = FakeMaskWorker;
  (globalThis as unknown as { createImageBitmap: typeof createImageBitmap }).createImageBitmap =
    async (blob: ImageBitmapSource) => {
      const b = blob instanceof Blob ? FakeMaskWorker.behaviorFor(blob) : { w: 1000, h: 900 };
      return { width: b.w, height: b.h, close() {} } as ImageBitmap;
    };
}

function restoreGlobals() {
  if (RealWorker === undefined) {
    delete (globalThis as unknown as { Worker?: unknown }).Worker;
  } else {
    globalThis.Worker = RealWorker;
  }
  if (RealCreateImageBitmap === undefined) {
    delete (globalThis as unknown as { createImageBitmap?: unknown }).createImageBitmap;
  } else {
    globalThis.createImageBitmap = RealCreateImageBitmap;
  }
}

afterEach(() => {
  restoreGlobals();
});

async function settleOverlay(
  s: ReturnType<typeof createCaptureSession>,
  ms = 2500,
): Promise<Mask> {
  const start = Date.now();
  while (Date.now() - start < ms) {
    const cap = get(s.capture);
    if (cap.k === 'mask' && cap.overlay && cap.overlay.slabPx > 0) return cap.overlay;
    await new Promise((r) => setTimeout(r, 5));
  }
  throw new Error('mask overlay never settled');
}

async function driveToMeasure(
  s: ReturnType<typeof createCaptureSession>,
  photos: File[],
  calIndex: number,
  maskParams: Partial<MaskParams> = { sheet: 'green', sensitivity: 50 },
) {
  for (const p of photos) await s.addToBatch(p);
  s.continueBatch();
  s.pickCalibration(calIndex);
  if (typeof maskParams.sensitivity === 'number') s.setSensitivity(maskParams.sensitivity);
  // setSheet runs an immediate pass (after sensitivity so the pass sees frozen params)
  s.setSheet(maskParams.sheet ?? 'auto');
  await settleOverlay(s);
  s.approveMask();
  s.approveAxis();
  s.setLength(320); // 40 in
  s.setThickness(16); // 2 in
}

test('test(photos): Calculate stores overlayPng on results, clean inventory untouched (#63)', async () => {
  installFakes();
  let encodeN = 0;
  const s = createCaptureSession({
    draft: store,
    encodeInventory: async () => {
      encodeN++;
      return {
        blob: new Blob([`clean-${encodeN}`], { type: 'image/png' }),
        sourceBelowFloor: false,
      };
    },
  } as Parameters<typeof createCaptureSession>[0]);

  const a = tinyJpeg('a');
  const b = tinyJpeg('b'); // cal
  await driveToMeasure(s, [a, b], 1, { sheet: 'green' });
  await s.calculate();

  const cap = get(s.capture);
  assert.equal(cap.k, 'measure');
  if (cap.k !== 'measure') return;
  assert.ok(cap.results, 'results present');
  assert.ok(cap.results!.inventoryPng, 'clean cal PNG in results.inventoryPng');
  assert.equal(cap.results!.inventoryPng.type, 'image/png');

  const overlay = (cap.results as { overlayPng?: Blob }).overlayPng;
  assert.ok(overlay, 'results.overlayPng must exist after Calculate (#63)');
  assert.equal(overlay!.type, 'image/png');
  assert.notEqual(overlay, cap.results!.inventoryPng, 'overlay is a second copy, not the clean PNG');

  const apply = (cap as { batchApply?: unknown[] }).batchApply;
  assert.ok(Array.isArray(apply));
  assert.equal(apply![1], null, 'batchApply[cal] stays null');
  assert.ok(apply![0] && (apply![0] as { status: string }).status === 'ok', 'siblings unchanged');

  s.dispose();
});

test('test(photos): single-photo batch still yields clean + overlayPng (#63)', async () => {
  installFakes();
  const s = createCaptureSession({
    draft: store,
    encodeInventory: async () => ({
      blob: new Blob(['only-clean'], { type: 'image/png' }),
      sourceBelowFloor: false,
    }),
  } as Parameters<typeof createCaptureSession>[0]);

  await driveToMeasure(s, [tinyJpeg('only')], 0, { sheet: 'auto' });
  await s.calculate();

  const cap = get(s.capture);
  assert.equal(cap.k, 'measure');
  if (cap.k !== 'measure') return;
  assert.ok(cap.results!.inventoryPng);
  assert.ok((cap.results as { overlayPng?: Blob }).overlayPng, 'overlay even for batch of one');
  assert.deepEqual((cap as { batchApply?: unknown[] }).batchApply, [null]);
  s.dispose();
});

test('test(photos): draft persists overlayPng alongside inventoryPng (#63)', async () => {
  installFakes();
  const s = createCaptureSession({
    draft: store,
    encodeInventory: async () => ({
      blob: new Blob(['draft-clean'], { type: 'image/png' }),
      sourceBelowFloor: false,
    }),
  } as Parameters<typeof createCaptureSession>[0]);

  await driveToMeasure(s, [tinyJpeg('a'), tinyJpeg('b')], 0, { sheet: 'black' });
  await s.calculate();
  await new Promise((r) => setTimeout(r, 30));

  const d = store.peek();
  assert.ok(d);
  assert.equal(d!.stage, 'measure');
  assert.ok(d!.inventoryPng, 'draft keeps clean inventory');
  assert.ok(
    (d as { overlayPng?: Blob | null }).overlayPng,
    'draft.overlayPng must be persisted for #64 lineup',
  );
  assert.equal(d!.batchApply![0], null, 'cal slot still null on draft');
  s.dispose();
});

test('test(photos): dishonest proxies absent — no raw-photo overlay / no cal-slot stash (#63)', async () => {
  const sessionSrc = readFileSync(join(here, 'session.ts'), 'utf8');
  const overlaySrcPath = join(here, '..', 'png', 'overlay.ts');
  let overlaySrc = '';
  try {
    overlaySrc = readFileSync(overlaySrcPath, 'utf8');
  } catch {
    overlaySrc = '';
  }
  assert.ok(
    /overlayPng|encodeOverlay|dimensionOverlay|buildOverlayPlan/i.test(sessionSrc) ||
      overlaySrc.length > 0,
    'session or png/overlay must implement dimension overlay (#63)',
  );
  const calcBody = sessionSrc.match(/async calculate\(\)[\s\S]*?(?=\n    [a-zA-Z]+\(|\n  \})/);
  assert.ok(calcBody, 'calculate() must exist');
  assert.ok(
    !/batchApply\s*\[\s*calIndex\s*\]\s*=\s*\{[^}]*overlay/i.test(calcBody![0]),
    'must not put overlay into batchApply[cal]',
  );
});