import 'dart:convert';
import 'dart:typed_data';

import 'package:desktop_plugin/image/card_image.dart';
import 'package:desktop_plugin/print/pavo/pavo_ffi.dart';
import 'package:desktop_plugin/print/pavo/pavo_printer.dart';
import 'package:flutter_test/flutter_test.dart';
import 'package:image/image.dart';

String dataUrl(Image img) => 'data:image/png;base64,${base64.encode(encodePng(img))}';

void main() {
  group('CardImage 像素层转换', () {
    test('横向图缩放到 1014×642，纯红转 BGR 字节序正确', () {
      final img = Image(width: 100, height: 50);
      fill(img, color: ColorRgb8(255, 0, 0));
      final card = CardImage.fromDataUrl(dataUrl(img));
      expect(card.isLandscape, isTrue);
      expect(card.width, 1014);
      expect(card.height, 642);
      final bgr = card.toBgr24();
      expect(bgr.length, 1014 * 642 * 3);
      // 红色像素 → BGR 序 [B=0, G=0, R=255]
      expect(bgr[0], 0);
      expect(bgr[1], 0);
      expect(bgr[2], 255);
      // 中间像素一致（无行对齐错位/跨行污染）
      final mid = (642 ~/ 2) * 1014 * 3 + (1014 ~/ 2) * 3;
      expect(bgr[mid], 0);
      expect(bgr[mid + 1], 0);
      expect(bgr[mid + 2], 255);
    });

    test('纵向图缩放到 642×1014，纯蓝转 BGR 正确', () {
      final img = Image(width: 50, height: 100);
      fill(img, color: ColorRgb8(0, 0, 255));
      final card = CardImage.fromDataUrl(dataUrl(img));
      expect(card.isLandscape, isFalse);
      expect(card.width, 642);
      expect(card.height, 1014);
      final bgr = card.toBgr24();
      // 蓝色像素 → BGR 序 [B=255, G=0, R=0]
      expect(bgr[0], 255);
      expect(bgr[1], 0);
      expect(bgr[2], 0);
    });

    test('透明像素铺白，避免黑底', () {
      // 注意：image v4 的 Image() 默认是 3 通道不透明黑，透明图必须显式 numChannels: 4
      final img = Image(width: 100, height: 50, numChannels: 4); // RGBA(0,0,0,0) 全透明
      final card = CardImage.fromDataUrl(dataUrl(img));
      final bgr = card.toBgr24();
      expect(bgr[0], 255);
      expect(bgr[1], 255);
      expect(bgr[2], 255);
    });

    test('灰度转换：红 ≈ 76、白 = 255（K 层白底黑字语义）', () {
      final red = Image(width: 100, height: 50);
      fill(red, color: ColorRgb8(255, 0, 0));
      final card = CardImage.fromDataUrl(dataUrl(red));
      final gray = card.toGray8();
      expect(gray.length, 1014 * 642);
      expect(gray[0], 255 * 299 ~/ 1000); // = 76
      expect(gray.every((g) => g == 76), isTrue);

      final white = Image(width: 100, height: 50);
      fill(white, color: ColorRgb8(255, 255, 255));
      expect(CardImage.fromDataUrl(dataUrl(white)).toGray8()[0], 255);
    });

    test('空 data URL 报错', () {
      expect(() => CardImage.fromDataUrl(''), throwsArgumentError);
    });
  });

  group('PavoPrinter 纯 Dart 工具', () {
    test('decodeAuto 识别 UTF-8 / UTF-16 打印机名', () {
      // 纯 ASCII：UTF-8 解码即可正确还原（NUL 计入可打印率，两种编码都可能命中 UTF-8 路径）
      final ascii = Uint8List.fromList('HiTi CS-200e'.codeUnits);
      expect(PavoPrinter.decodeAuto(ascii).startsWith('HiTi CS-200e'), isTrue);
      // 纯中文：UTF-8 解码得乱码（可打印率低），走 UTF-16 路径正确还原
      // （ASCII 混中文时 NUL 也计入可打印率，可能仍走 UTF-8 路径——与 C# 行为一致）
      final name = '证卡打印机';
      final bytes = <int>[];
      for (final c in name.codeUnits) {
        bytes..add(c & 0xff)..add(c >> 8);
      }
      expect(PavoPrinter.decodeAuto(Uint8List.fromList(bytes)), name);
    });

    test('statusTextOf 状态文案', () {
      expect(PavoPrinter.statusTextOf(0), '就绪');
      expect(PavoPrinter.statusTextOf(PavoApi.dsOutOfRibbon), '色带已用尽，请更换色带');
      expect(PavoPrinter.statusTextOf(0x12345678), contains('设备状态异常'));
    });
  });
}