import 'dart:convert';

import 'package:fis_common/env/env.dart';
import 'package:fis_common/js_plateform/js_platform.dart';
import 'package:fis_lib_print/printing.dart';
import 'package:flutter/foundation.dart';
import 'package:flyinsonolite/consultation/reports/pdf/reportrender.dart';
import 'package:flyinsonolite/consultation/reports/pdf/resourcescache.dart';
import 'package:pdf/pdf.dart';
import 'package:http/http.dart' as http;

/// PDF 各项功能【打印】【导出】
class PDFHelper {
  PDFHelper();

  /// 打印文档格式的 PDF
  static void printPDF(String fileName, ReportDataPipe pipe) async {
    try {
      _preProcessData(fileName, pipe);
      var bytes = await generateReport(PdfPageFormat.a4, null);
      _handelPrint(bytes);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  /// 下载（导出）文档格式 PDF【在壳子环境下会调用壳子提供的文件导出能力】
  static Future<void> downloadPDF(
    String fileName,
    ReportDataPipe pipe,
    Future<bool> Function(List<int> data, String fileName)? pdfExporter,
  ) async {
    try {
      _preProcessData(fileName, pipe);
      var bytes = await generateReport(PdfPageFormat.a4, null);
      await _handelDownload(bytes, fileName, pdfExporter);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  /// 打印图片格式的 PDF
  static void printPDFJpges(String fileName, List<String>? images) async {
    try {
      ResourcesCache.clearCachedPDF();
      var bytes = await generateByGivenPDFJpges(PdfPageFormat.a4, images);
      _handelPrint(bytes);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  /// 打印文件格式的 PDF
  static void printPDFFile(String fileName, String fileUrl) async {
    try {
      ResourcesCache.clearCachedPDF();
      var bytes = await downloadFile(fileUrl);
      _handelPrint(bytes);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  /// 下载（导出）图片格式 PDF【在壳子环境下会调用壳子提供的文件导出能力】
  static void downloadPDFJpges(
    String fileName,
    List<String>? images,
    Future<bool> Function(List<int> data, String fileName)? pdfExporter,
  ) async {
    try {
      ResourcesCache.clearCachedPDF();
      var bytes = await generateByGivenPDFJpges(PdfPageFormat.a4, images);
      _handelDownload(bytes, fileName, pdfExporter);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  /// 下载（导出）文件格式 PDF【在壳子环境下会调用壳子提供的文件导出能力】
  static void downloadPDFFile(
    String fileName,
    String fileUrl,
    Future<bool> Function(List<int> data, String fileName)? pdfExporter,
  ) async {
    try {
      ResourcesCache.clearCachedPDF();
      var bytes = await downloadFile(fileUrl);
      _handelDownload(bytes, fileName, pdfExporter);
    } catch (e) {
      debugPrint(e.toString());
    }
  }

  static Future<Uint8List> downloadFile(String fileUrl) async {
    var response = await http.get(Uri.parse(fileUrl));
    if (response.statusCode == 200) {
      return response.bodyBytes;
    } else {
      throw Exception('Failed to download file');
    }
  }

  /// 处理打印的细节
  static void _handelPrint(Uint8List bytes) {
    var base64 = base64Encode(bytes);
    JSPlateForm.printPdf(base64);
  }

  /// 处理下载的细节
  static Future<void> _handelDownload(
    Uint8List bytes,
    String fileName,
    Future<bool> Function(List<int> data, String fileName)? pdfExporter,
  ) async {
    if (_useFileExporertUI()) {
      await pdfExporter!.call(bytes, fileName);
      return;
    }
    await Printing.sharePdf(
      bytes: bytes,
      filename: fileName,
    );
  }

  /// 下载（导出）时使用系统UI下载文件
  static bool _useFileExporertUI() {
    final platform = FPlatform.current;
    return platform == FPlatformEnum.webOnWin ||
        platform == FPlatformEnum.webOnMac;
  }

  /// 数据获取预处理
  static _preProcessData(String fileName, ReportDataPipe pipe) {
    ResourcesCache.clearCachedPDF();
    ResourcesCache.currentPDFFileKey = fileName;
    ResourcesCache.cacheGet = pipe.cacheGet;
    ResourcesCache.cacheSave = pipe.cacheSave;
  }
}

/// 数据读写通道
class ReportDataPipe {
  final Future<Uint8List?> Function(String fileName)? cacheGet;
  final Future<bool> Function(String fileName, Uint8List file)? cacheSave;
  ReportDataPipe({
    required this.cacheGet,
    required this.cacheSave,
  });
}