import { expect, test } from "@playwright/test";

import {
  defaultVideoCanvasSubtitleEraseConfig,
  detectSubtitleEraseRegions,
  moveSubtitleEraseRegion,
  normalizeVideoCanvasSubtitleEraseConfig,
  resizeSubtitleEraseRegion,
  type SubtitleEraseRegion,
} from "../../lib/video-canvas/subtitle-erase";

const region: SubtitleEraseRegion = {
  height: 0.1,
  id: "region-1",
  width: 0.4,
  x: 0.3,
  y: 0.7,
};

test.describe("video subtitle erase tools", () => {
  test("normalizes administrator processing limits", () => {
    expect(normalizeVideoCanvasSubtitleEraseConfig({
      blurRadius: 100,
      edgeThreshold: 0,
      frameRate: 200,
      smartSearchEndRatio: 0.2,
      smartSearchStartRatio: 0.8,
    })).toMatchObject({
      blurRadius: 40,
      edgeThreshold: 1,
      frameRate: 60,
      smartSearchEndRatio: 0.84,
      smartSearchStartRatio: 0.8,
    });
  });

  test("moves and resizes a selected erase region inside the source", () => {
    expect(moveSubtitleEraseRegion(region, 0.8, -0.8)).toEqual({
      ...region,
      x: 0.6,
      y: 0,
    });
    expect(resizeSubtitleEraseRegion(region, "se", 0.95, 0.95)).toEqual({
      ...region,
      height: 0.25,
      width: 0.65,
    });
  });

  test("detects a high-contrast subtitle band in the configured lower scan area", () => {
    const width = 120;
    const height = 100;
    const data = new Uint8ClampedArray(width * height * 4);
    for (let y = 0; y < height; y += 1) {
      for (let x = 0; x < width; x += 1) {
        const index = (y * width + x) * 4;
        const value = y >= 65 && y <= 74 && x >= 12 && x <= 108
          ? (x % 4 < 2 ? 255 : 0)
          : 48;
        data[index] = value;
        data[index + 1] = value;
        data[index + 2] = value;
        data[index + 3] = 255;
      }
    }
    const detected = detectSubtitleEraseRegions(
      { data, height, width } as ImageData,
      {
        ...defaultVideoCanvasSubtitleEraseConfig,
        edgeThreshold: 30,
        minBandHeightRatio: 0.01,
      },
    );

    expect(detected).toHaveLength(1);
    expect(detected[0]).toMatchObject({ id: "smart-subtitle-1", width: 0.94, x: 0.03 });
    expect(detected[0].y).toBeGreaterThan(0.6);
    expect(detected[0].y + detected[0].height).toBeLessThan(0.8);
  });
});