import 'dart:io';
import 'package:flutter_test/flutter_test.dart';
import 'package:image/image.dart' as img;
import 'package:app_pfm_ocr_v2/features/camera/blur_detector.dart';

void main() {
  test('BlurDetector TDD algorithm test with document borders', () async {
    final tempDir = Directory.systemTemp.createTempSync();
    final sharpFile = File('${tempDir.path}/sharp_doc.png');
    final blurFile = File('${tempDir.path}/blur_doc.png');

    // 1. Generate a sharp document with a black background
    // Size: 200x200
    final sharpImg = img.Image(width: 200, height: 200);
    // Fill with black (background table)
    img.fill(sharpImg, color: img.ColorRgb8(0, 0, 0));
    
    // Draw white document in the center (from 40 to 160)
    for (int y = 40; y < 160; y++) {
      for (int x = 40; x < 160; x++) {
        // Draw sharp alternating stripes inside the document to simulate sharp text
        final isStripe = (x % 6 < 3);
        final colorVal = isStripe ? 0 : 255;
        sharpImg.setPixelRgba(x, y, colorVal, colorVal, colorVal, 255);
      }
    }
    sharpFile.writeAsBytesSync(img.encodePng(sharpImg));

    // 2. Generate a blurry document with the same black background
    final blurImg = img.Image(width: 200, height: 200);
    img.fill(blurImg, color: img.ColorRgb8(0, 0, 0));
    
    // Draw white document in the center (from 40 to 160)
    for (int y = 40; y < 160; y++) {
      for (int x = 40; x < 160; x++) {
        // Draw solid white or very blurry gray stripes (low contrast)
        blurImg.setPixelRgba(x, y, 220, 220, 220, 255);
      }
    }
    // To make it look like a blurred document, we also blur the edges of the white card slightly
    final blurredDocImg = img.gaussianBlur(blurImg, radius: 2);
    blurFile.writeAsBytesSync(img.encodePng(blurredDocImg));

    // 3. Run BlurDetector
    final sharpResult = await BlurDetector.checkBlur(sharpFile.path);
    final blurResult = await BlurDetector.checkBlur(blurFile.path);

    print('TDD Sharp Doc Score: ${sharpResult.score} (Raw: ${sharpResult.rawScore}, IsBlur: ${sharpResult.isBlur})');
    print('TDD Blur Doc Score: ${blurResult.score} (Raw: ${blurResult.rawScore}, IsBlur: ${blurResult.isBlur})');

    // 4. Assertions
    // The sharp document must be detected as sharp (score >= 80.0)
    expect(sharpResult.score, greaterThanOrEqualTo(80.0));
    expect(sharpResult.isBlur, isFalse);

    // The blurry document must be detected as blurry (score < 80.0)
    expect(blurResult.score, lessThan(80.0));
    expect(blurResult.isBlur, isTrue);

    // Clean up
    try {
      sharpFile.deleteSync();
      blurFile.deleteSync();
      tempDir.deleteSync();
    } catch (_) {}
  });
}