import 'dart:convert';

import 'package:flutter/cupertino.dart';
import 'package:http/http.dart' as http;

import 'package:package_info_plus/package_info_plus.dart';

class UpdateInfo {
  final bool update;
  final String version;
  final String notes;
  final bool mandatory;
  final String sha256;
  final String download;

  UpdateInfo({
    required this.update,
    required this.version,
    required this.notes,
    required this.mandatory,
    required this.sha256,
    required this.download,
  });

  factory UpdateInfo.fromJson(Map<String, dynamic> json) {
    return UpdateInfo(
      update: json["update"] ?? false,
      version: json["version"] ?? "",
      notes: json["notes"] ?? "",
      mandatory: json["mandatory"] ?? false,
      sha256: json["sha256"] ?? "",
      download: json["download"] ?? "",
    );
  }

  @override
  bool operator ==(Object other) =>
      identical(this, other) ||
      other is UpdateInfo &&
          update == other.update &&
          version == other.version &&
          notes == other.notes &&
          mandatory == other.mandatory &&
          sha256 == other.sha256 &&
          download == other.download;

  @override
  int get hashCode =>
      Object.hash(update, version, notes, mandatory, sha256, download);
}

class AppUpdateUtil {
  final String serverUrl;

  AppUpdateUtil({required this.serverUrl});

  /// Gets the installed app version
  Future<String> currentVersion() async {
    final info = await PackageInfo.fromPlatform();
    debugPrint("Current app version: ${info.version}");
    return info.version;
  }

  /// Checks the update server
  Future<UpdateInfo?> checkForUpdate() async {
    final version = await currentVersion();

    final url = Uri.parse("$serverUrl/api/update?version=$version");

    final response = await http.get(url);

    debugPrint("Response from update server: ${response.body}");

    if (response.statusCode != 200) {
      throw Exception("Update server unavailable");
    }

    final data = jsonDecode(response.body);

    if (data["update"] != true) {
      return null;
    }

    return UpdateInfo.fromJson(data);
  }

  // /// Downloads the APK
  // Future<File> downloadApk(
  //   UpdateInfo update, {
  //
  //   Function(double progress)? onProgress,
  // }) async {
  //   final url = update.download.startsWith("http")
  //       ? update.download
  //       : "$serverUrl${update.download}";
  //
  //   final request = http.Request("GET", Uri.parse(url));
  //
  //   final response = await request.send();
  //
  //   if (response.statusCode != 200) {
  //     throw Exception("APK download failed");
  //   }
  //
  //   final total = response.contentLength ?? 0;
  //
  //   int received = 0;
  //
  //   final directory = await getTemporaryDirectory();
  //
  //   final file = File("${directory.path}/update.apk");
  //
  //   final sink = file.openWrite();
  //
  //   await for (final chunk in response.stream) {
  //     sink.add(chunk);
  //
  //     received += chunk.length;
  //
  //     if (total > 0 && onProgress != null) {
  //       onProgress(received / total);
  //     }
  //   }
  //
  //   await sink.close();
  //
  //   return file;
  // }
  //
  // /// Verifies APK checksum
  // Future<bool> verifySha256(File file, String expectedHash) async {
  //   final bytes = await file.readAsBytes();
  //
  //   final digest = sha256.convert(bytes);
  //
  //   return digest.toString().toLowerCase() == expectedHash.toLowerCase();
  // }
  //
  // /// Opens Android APK installer
  // Future<void> installApk(File file) async {
  //   final result =
  //   await OpenFilex.open(
  //     file.path,
  //   );
  //
  //   if(result.type == ResultType.done) {
  //     debugPrint("APK installer opened successfully");
  //   }
  //
  //
  //   if (result.type != ResultType.done) {
  //     throw Exception(
  //       "Could not open APK installer",
  //     );
  //   }
  // }
  //
  // /// Full update flow
  // ///
  // /// Returns:
  // /// - null if no update exists
  // /// - UpdateInfo if update is available
  // ///
  // Future<UpdateInfo?> update({Function(double progress)? onProgress}) async {
  //   final info = await checkForUpdate();
  //
  //   if (info == null) {
  //     return null;
  //   }
  //
  //   final apk = await downloadApk(info, onProgress: onProgress);
  //
  //   final valid = await verifySha256(apk, info.sha256);
  //
  //   if (!valid) {
  //     throw Exception("APK checksum mismatch");
  //   }
  //
  //   await installApk(apk);
  //
  //   return info;
  // }
}