import { describe, expect, it } from "vitest";
import {
  confirmMask,
  createMaskSession,
  defaultKnobs,
  removeSheetBackground,
  reRunMask,
  requestRetake,
} from "../lib/pipeline/mask.js";
import {
  blackSheetFixture,
  greenSheetFixture,
  maskAt,
} from "./fixtures/synthetic.js";

describe("TV-1 green-sheet chroma-key", () => {
  it("keeps interior green-ish patch that does not touch the border", () => {
    const { image, interiorGreen, woodSample, borderSample } = greenSheetFixture();
    const knobs = { ...defaultKnobs(), sheet: "green" as const };
    const result = removeSheetBackground(image, knobs);

    expect(result.u2netInvoked).toBe(false);
    expect(result.sheetUsed).toBe("green");
    expect(maskAt(result.mask, result.width, borderSample.x, borderSample.y)).toBe(0);
    expect(maskAt(result.mask, result.width, woodSample.x, woodSample.y)).toBeGreaterThan(0);
    expect(
      maskAt(result.mask, result.width, interiorGreen.x, interiorGreen.y),
    ).toBeGreaterThan(0);
  });

  it("re-runs live when knobs change and still skips U2Net", () => {
    const { image } = greenSheetFixture();
    const first = removeSheetBackground(image, { ...defaultKnobs(), sheet: "green" });
    const second = reRunMask(image, {
      ...defaultKnobs(),
      sheet: "green",
      sensitivity: 0.7,
      edgeOffset: 1,
      feather: 1,
    });
    expect(first.u2netInvoked).toBe(false);
    expect(second.u2netInvoked).toBe(false);
    expect(second.knobs.sensitivity).toBe(0.7);
  });
});

describe("TV-2 black-sheet threshold + border flood-fill", () => {
  it("keeps dark interior wood that does not touch the border", () => {
    const { image, darkInterior, woodSample, borderSample } = blackSheetFixture();
    const knobs = { ...defaultKnobs(), sheet: "black" as const };
    const result = removeSheetBackground(image, knobs);

    expect(result.u2netInvoked).toBe(false);
    expect(result.sheetUsed).toBe("black");
    expect(maskAt(result.mask, result.width, borderSample.x, borderSample.y)).toBe(0);
    expect(maskAt(result.mask, result.width, woodSample.x, woodSample.y)).toBeGreaterThan(0);
    expect(
      maskAt(result.mask, result.width, darkInterior.x, darkInterior.y),
    ).toBeGreaterThan(0);
  });

  it("flood-fill removes only border-connected dark pixels", () => {
    const { image, darkInterior, borderSample } = blackSheetFixture();
    const result = removeSheetBackground(image, { ...defaultKnobs(), sheet: "black" });
    // Border sheet gone; isolated dark island kept.
    expect(maskAt(result.mask, result.width, borderSample.x, borderSample.y)).toBe(0);
    expect(
      maskAt(result.mask, result.width, darkInterior.x, darkInterior.y),
    ).toBeGreaterThan(0);
  });
});

describe("mask confirm hooks (pure)", () => {
  it("starts pending, confirm and retake transition without DOM", () => {
    const { image } = greenSheetFixture();
    const result = removeSheetBackground(image, { ...defaultKnobs(), sheet: "green" });
    const session = createMaskSession(result);
    expect(session.state).toBe("pending");
    expect(confirmMask(session).state).toBe("confirmed");
    expect(requestRetake(session).state).toBe("retake");
  });
});