import { describe, expect, test } from "bun:test";
import { blurMaskValues, cropMaskValuesToRgba, dilateMaskValues, erodeMaskValues, expandRectWithinBounds, invertMaskValues } from "./maskRaster";

describe("mask raster utilities", () => {
  test("exports the normalized drawn mask without filling the whole crop", () => {
    const revealedMask = new Uint8ClampedArray(4 * 3).fill(255);
    revealedMask[1 * 4 + 2] = 0;

    const inpaintMask = invertMaskValues(revealedMask);
    const rgba = cropMaskValuesToRgba(inpaintMask, 4, 3, { x: 1, y: 0, w: 3, h: 3 }, 4, 4);
    const activePixels = activeRedPixels(rgba);

    expect(activePixels).toEqual([{ x: 1, y: 1 }]);
    for (let pixel = 0; pixel < rgba.length / 4; pixel += 1) expect(rgba[pixel * 4 + 3]).toBe(255);
  });

  test("expands masked-area crops to the model minimum when possible", () => {
    expect(expandRectWithinBounds({ x: 20, y: 20, w: 4, h: 4 }, 4, { w: 100, h: 100 }, 8, 64)).toEqual({
      x: 0,
      y: 0,
      w: 64,
      h: 64,
    });
    expect(expandRectWithinBounds({ x: 80, y: 80, w: 4, h: 4 }, 4, { w: 100, h: 100 }, 8, 64)).toEqual({
      x: 36,
      y: 36,
      w: 64,
      h: 64,
    });
  });

  test("uses separable mask kernels without changing square-kernel semantics", () => {
    const values = new Uint8ClampedArray([0, 0, 0, 0, 255, 0, 0, 0, 0]);
    expect([...dilateMaskValues(values, 3, 3, 1)]).toEqual(new Array(9).fill(255));
    expect([...erodeMaskValues(new Uint8ClampedArray(new Array(9).fill(255)), 3, 3, 1)]).toEqual(new Array(9).fill(255));
    expect([...blurMaskValues(values, 3, 3, 1)]).toEqual(new Array(9).fill(28));
  });
});

function activeRedPixels(rgba: Uint8ClampedArray) {
  const width = 4;
  const pixels: Array<{ x: number; y: number }> = [];
  for (let pixel = 0; pixel < rgba.length / 4; pixel += 1) {
    if ((rgba[pixel * 4] ?? 0) > 127) pixels.push({ x: pixel % width, y: Math.floor(pixel / width) });
  }
  return pixels;
}