import 'package:flutter/material.dart';
import 'package:ffi/ffi.dart';
import 'package:path_provider/path_provider.dart';
import 'dart:io';
import 'dart:ffi';
import 'dart:async';
import 'dart:convert';

class HexColor extends Color {
  HexColor(final String hexColor) : super(_getColorFromHex(hexColor));

  static int _getColorFromHex(String hexColor) {
    hexColor = hexColor.toUpperCase().replaceAll('#', '');
    if (hexColor.length == 6) {
      hexColor = 'FF' + hexColor;
    }
    return int.parse(hexColor, radix: 16);
  }
}

class MyTheme {
  static const Color grayBg = Color(0xFFEEEEEE);
  static const Color white = Color(0xFFFFFFFF);
}

typedef F1 = void Function(Pointer<Utf8>);
typedef F2 = Pointer<Utf8> Function(Pointer<Utf8>);
typedef F3 = void Function(Pointer<Utf8>, Pointer<Utf8>);

// https://juejin.im/post/6844903864852807694
class FfiModel with ChangeNotifier {
  F1 _freeCString;
  F2 _getByName;
  F3 _setByName;

  FfiModel() {
    initialzeFFI();
  }

  void addRemote() {
    notifyListeners();
  }

  void connect(String id) {
    setByName("connect", id);
    _setByName(Utf8.toUtf8("connect"), Utf8.toUtf8(id));
  }

  void setByName(String name, String value) {
    _setByName(Utf8.toUtf8(name), Utf8.toUtf8(value));
  }

  String getByName(String name) {
    var p = _getByName(Utf8.toUtf8(name));
    var res = Utf8.fromUtf8(p);
    // https://github.com/brickpop/flutter-rust-ffi
    _freeCString(p);
    return res;
  }

  String getId() {
    return getByName("remote_id");
  }

  List<Peer> peers() {
    try {
      List<dynamic> peers = json.decode(getByName("peers"));
      return peers
          .map((s) => s as List<dynamic>)
          .map((s) =>
              Peer.fromJson(s[0] as String, s[1] as Map<String, dynamic>))
          .toList();
    } catch (e) {
      print(e);
    }
    return [];
  }

  Future<Null> initialzeFFI() async {
    final dylib = Platform.isAndroid
        ? DynamicLibrary.open('librustdesk.so')
        : DynamicLibrary.process();
    _getByName = dylib.lookupFunction<F2, F2>('get_by_name');
    _setByName =
        dylib.lookupFunction<Void Function(Pointer<Utf8>, Pointer<Utf8>), F3>(
            'set_by_name');
    _freeCString = dylib
        .lookupFunction<Void Function(Pointer<Utf8>), F1>('rust_cstr_free');
    final dir = (await getApplicationDocumentsDirectory()).path;
    setByName("init", dir);
    notifyListeners();
  }
}

class Peer {
  final String id;
  final String username;
  final String hostname;
  final String platform;

  Peer.fromJson(String id, Map<String, dynamic> json)
      : id = id,
        username = json['username'],
        hostname = json['hostname'],
        platform = json['platform'];
}