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);
  }
}