import 'dart:io';
import 'dart:typed_data';
import 'dart:ui' as ui;

import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:intl/intl.dart';
import 'package:path_provider/path_provider.dart';
import 'package:chicken_farm/core/utils/logger.dart';
import 'package:flutter_image_compress/flutter_image_compress.dart';

class WatermarkedCamera extends StatefulWidget {
  final Function(File)? onImageCaptured;
  final String? watermarkText;
  final String? watermarkDateText;

  const WatermarkedCamera({
    super.key,
    this.onImageCaptured,
    this.watermarkText,
    this.watermarkDateText,
  });

  @override
  State<WatermarkedCamera> createState() => _WatermarkedCameraState();
}

class _WatermarkedCameraState extends State<WatermarkedCamera> {
  XFile? _capturedImage;
  File? _watermarkedImage;
  bool _isProcessing = false;

  // 添加状态标记，用于判断是否已初始化拍照
  bool _initialized = false;

  @override
  void initState() {
    super.initState();
    // 在初始化时自动启动拍照
    WidgetsBinding.instance.addPostFrameCallback((_) {
      _takePicture();
      _initialized = true;
    });
  }

  Future<void> _takePicture() async {
    try {
      final ImagePicker picker = ImagePicker();
      final XFile? photo = await picker.pickImage(
        source: ImageSource.camera,
        imageQuality: 80,
      );

      if (photo != null) {
        setState(() {
          _capturedImage = photo;
          _isProcessing = true;
        });

        // 压缩图片后再添加水印
        final compressedImage = await _compressImage(photo);
        // 添加水印并处理图像
        await _addWatermark(compressedImage);
      } else {
        // 如果用户取消拍照，则关闭页面
        if (mounted && _initialized) {
          Navigator.of(context).pop();
        }
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('拍照失败: $e')));
      }
      logger.e('拍照失败: $e');

      // 出错时也关闭页面
      if (mounted && _initialized) {
        Navigator.of(context).pop();
      }
    }
  }

  /// 压缩图片以确保文件大小在500KB以内
  Future<XFile> _compressImage(XFile imageFile) async {
    try {
      final tempDir = await getTemporaryDirectory();
      final originalFile = File(imageFile.path);
      final originalSize = await originalFile.length();

      logger.i('原始图片大小: ${originalSize / 1024} KB');

      // 如果原始文件已经小于500KB，直接返回
      if (originalSize <= 500 * 1024) {
        return imageFile;
      }

      // 初始压缩参数
      int quality = 50;
      int minWidth = 1024;
      int minHeight = 768;

      XFile? bestCompressedFile;
      int bestFileSize = originalSize.toInt();
      String bestFilePath = '';

      // 迭代压缩直到文件大小符合要求
      while (bestFileSize > 500 * 1024 && (quality >= 20 || minWidth >= 640)) {
        final targetPath =
            '${tempDir.path}/compressed_${DateTime.now().millisecondsSinceEpoch}_${quality}_$minWidth.jpg';

        final compressedFile = await FlutterImageCompress.compressAndGetFile(
          imageFile.path,
          targetPath,
          quality: quality,
          minWidth: minWidth,
          minHeight: minHeight,
        );

        if (compressedFile != null) {
          final compressedFileSize = await File(compressedFile.path).length();
          logger.i(
            '压缩后图片大小 ($quality% 质量, ${minWidth}x$minHeight): ${compressedFileSize / 1024} KB',
          );

          if (compressedFileSize <= 500 * 1024) {
            // 找到符合大小要求的文件
            if (compressedFileSize < bestFileSize) {
              bestCompressedFile = compressedFile;
              bestFileSize = compressedFileSize.toInt();
              bestFilePath = targetPath;
            }
            break;
          } else if (compressedFileSize < bestFileSize) {
            // 记录目前为止最小的文件
            bestCompressedFile = compressedFile;
            bestFileSize = compressedFileSize.toInt();
            bestFilePath = targetPath;
          }

          // 调整参数继续尝试
          if (quality > 20) {
            // 优先降低质量
            quality -= 10;
          } else if (minWidth > 640) {
            // 质量不能再低了，减小尺寸
            minWidth -= 128;
            minHeight = (minHeight * minWidth / (minWidth + 128))
                .toInt(); // 按比例缩小
            quality = 30; // 恢复一定质量
          } else {
            // 已经达到极限
            break;
          }
        } else {
          // 压缩失败，跳出循环
          break;
        }
      }

      // 清理其他临时文件，只保留最佳文件
      final dir = Directory(tempDir.path);
      await for (final file in dir.list()) {
        if (file.path.contains('compressed_') && file.path != bestFilePath) {
          try {
            await file.delete();
          } catch (e) {
            logger.w('删除临时文件失败: $e');
          }
        }
      }

      if (bestCompressedFile != null) {
        logger.i('最终图片大小: ${bestFileSize / 1024} KB');
        return bestCompressedFile;
      } else {
        // 如果所有尝试都失败，返回原始文件
        return imageFile;
      }
    } catch (e) {
      logger.e('图片压缩失败: $e');
      // 如果压缩过程中出错，返回原始文件
      return imageFile;
    }
  }

  Future<void> _addWatermark(XFile imageFile) async {
    try {
      // 获取水印文本
      String watermark =
          widget.watermarkDateText ??
          DateFormat('yyyy-MM-dd HH:mm:ss').format(DateTime.now());

      // 将图片转换为字节以便处理
      final Uint8List imageBytes = await imageFile.readAsBytes();

      // 创建图片对象
      final ui.Codec codec = await ui.instantiateImageCodec(imageBytes);
      final ui.FrameInfo frameInfo = await codec.getNextFrame();
      final ui.Image image = frameInfo.image;

      // 创建画布
      final ui.PictureRecorder recorder = ui.PictureRecorder();
      final ui.Canvas canvas = ui.Canvas(recorder);

      // 绘制原始图片
      canvas.drawImage(image, Offset.zero, ui.Paint());

      // 创建段落样式
      final ui.ParagraphStyle paragraphStyle = ui.ParagraphStyle(
        textAlign: TextAlign.right,
        fontSize: 36.0,
        textDirection: ui.TextDirection.ltr,
      );

      // 创建文字样式
      final ui.TextStyle textStyle = ui.TextStyle(
        color: const ui.Color(0xFFFFFFFF), // 纯白色
        fontSize: 36.0,
        fontWeight: ui.FontWeight.bold, // 加粗
        shadows: [
          ui.Shadow(
            blurRadius: 3.0,
            color: const ui.Color(0xFF000000), // 黑色阴影增强可读性
            offset: const Offset(2.0, 2.0),
          ),
        ],
      );

      double verticalOffset = image.height.toDouble() - 100;

      // 如果有watermarkText，则先绘制watermarkText
      if (widget.watermarkText != null && widget.watermarkText!.isNotEmpty) {
        final ui.ParagraphBuilder additionalParagraphBuilder =
            ui.ParagraphBuilder(paragraphStyle);
        additionalParagraphBuilder.pushStyle(textStyle);
        additionalParagraphBuilder.addText(widget.watermarkText!);

        final ui.Paragraph additionalParagraph =
            additionalParagraphBuilder.build()
              ..layout(ui.ParagraphConstraints(width: image.width.toDouble()));

        verticalOffset -= 70;

        // 绘制watermarkText（在时间戳上方）
        canvas.drawParagraph(
          additionalParagraph,
          Offset(
            image.width.toDouble() - additionalParagraph.width - 90,
            verticalOffset,
          ),
        );
      }

      // 绘制时间戳水印
      final ui.ParagraphBuilder paragraphBuilder = ui.ParagraphBuilder(
        paragraphStyle,
      );
      paragraphBuilder.pushStyle(textStyle);
      paragraphBuilder.addText(watermark);

      final ui.Paragraph paragraph = paragraphBuilder.build()
        ..layout(ui.ParagraphConstraints(width: image.width.toDouble()));

      // 在右下角绘制时间戳水印
      canvas.drawParagraph(
        paragraph,
        Offset(
          image.width.toDouble() - paragraph.width - 90,
          verticalOffset + 60,
        ),
      );

      // 完成绘制
      final ui.Picture picture = recorder.endRecording();
      final ui.Image watermarkedImage = await picture.toImage(
        image.width,
        image.height,
      );

      // 转换为字节数据（PNG格式）
      final ByteData? byteData = await watermarkedImage.toByteData(
        format: ui.ImageByteFormat.png,
      );

      if (byteData != null) {
        // 保存到临时文件
        final tempDir = await getTemporaryDirectory();
        final file = File(
          '${tempDir.path}/watermarked_${DateTime.now().millisecondsSinceEpoch}.png',
        );
        await file.writeAsBytes(byteData.buffer.asUint8List());

        // 检查文件大小，如超过500KB则再压缩一次
        final fileSize = await file.length();
        logger.i('添加水印后图片大小: ${fileSize / 1024} KB');

        if (fileSize > 500 * 1024) {
          // 再次压缩
          final reCompressedFile = await _compressImage(XFile(file.path));
          setState(() {
            _watermarkedImage = File(reCompressedFile.path);
            _isProcessing = false;
          });
        } else {
          setState(() {
            _watermarkedImage = file;
            _isProcessing = false;
          });
        }
      } else {
        setState(() {
          _isProcessing = false;
        });

        if (mounted) {
          ScaffoldMessenger.of(
            context,
          ).showSnackBar(const SnackBar(content: Text('处理图片失败')));
        }
        logger.e('处理图片失败');
      }
    } catch (e) {
      setState(() {
        _isProcessing = false;
      });

      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('添加水印失败: $e')));
      }
      logger.e('添加水印失败: $e');
    }
  }

  void _confirmImage() {
    if (_watermarkedImage != null && widget.onImageCaptured != null) {
      widget.onImageCaptured!(_watermarkedImage!);
    }

    Navigator.of(context).pop();
  }

  void _retakePicture() {
    setState(() {
      _capturedImage = null;
      _watermarkedImage = null;
    });

    // 重新拍照
    _takePicture();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('拍照'),
        leading: IconButton(
          icon: const Icon(Icons.close),
          onPressed: () => Navigator.of(context).pop(),
        ),
      ),
      body: Column(
        children: [
          Expanded(
            child: _isProcessing
                ? const Center(child: CircularProgressIndicator())
                : Center(
                    child: _watermarkedImage != null
                        ? Image.file(_watermarkedImage!)
                        : _capturedImage != null
                        ? Image.file(File(_capturedImage!.path))
                        : const SizedBox(), // 避免显示默认提示信息
                  ),
          ),
          Padding(
            padding: const EdgeInsets.all(16.0),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceEvenly,
              children: [
                if (_capturedImage != null && !_isProcessing)
                  Row(
                    mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                    children: [
                      ElevatedButton(
                        onPressed: _retakePicture,
                        style: ElevatedButton.styleFrom(
                          backgroundColor: Colors.grey,
                          foregroundColor: Colors.white,
                        ),
                        child: const Text('重新拍照'),
                      ),
                      const SizedBox(width: 16.0),
                      ElevatedButton(
                        onPressed: _confirmImage,
                        style: ElevatedButton.styleFrom(
                          backgroundColor: Colors.green,
                          foregroundColor: Colors.white,
                        ),
                        child: const Text('确认提交'),
                      ),
                    ],
                  ),
              ],
            ),
          ),
        ],
      ),
    );
  }
}