import 'dart:convert';

import 'package:bugvault/server/main.dart';
import 'package:bugvault/users/User.dart';
import 'package:libac_dart/nbt/Tag.dart';
import 'package:libac_dart/nbt/impl/CompoundTag.dart';
import 'package:libac_dart/nbt/impl/IntTag.dart';
import 'package:libac_dart/nbt/impl/StringTag.dart';
import 'package:libac_dart/packets/packets.dart';

class C2SPacketLogin implements IPacket {
  String username = "";

  @override
  void decodeJson(String params) {
    fromJson(json.decode(params));
  }

  @override
  void decodeTag(Tag tag) {
    CompoundTag ct = tag.asCompoundTag();
    username = ct.get("user")?.asString() ?? "";
  }

  @override
  NetworkDirection direction() {
    return NetworkDirection.ClientToServer;
  }

  @override
  String encodeJson() {
    return json.encode(toJson());
  }

  @override
  Tag encodeTag() {
    CompoundTag ct = CompoundTag();
    ct.put("user", StringTag.valueOf(username));

    return ct;
  }

  @override
  void fromJson(Map<String, dynamic> js) {
    username = js['user'] as String;
  }

  @override
  String getChannelID() {
    return "BVPKTLOGIN";
  }

  @override
  Future<void> handleClientPacket() async {
    return;
  }

  @override
  Future<PacketResponse> handleServerPacket() async {
    S2CResponse response = S2CResponse();
    S2CLoginReply loginReply = S2CLoginReply();
    loginReply.username = username;

    // Check if the user exists
    DBUser? user = BugVaultServer.TryGetUser(username);
    if (user == null && username != "") {
      loginReply.g_ixLoginState |= LoginStates.NOT_FOUND;
      loginReply.g_ixLoginState |= LoginStates.PROVIDE_EMAIL;
    }

    if (user != null) {
      // Tell the user to send their TOTP Code
      loginReply.g_ixLoginState |= LoginStates.FOUND;
      loginReply.g_ixLoginState |= LoginStates.REQUIRE_MFA;
    }

    if (username == "") {
      if (BugVaultServer.g_bAllowAnonymousLogin) {
        loginReply.g_ixLoginState = LoginStates.LOGGED_IN;
      } else {
        loginReply.g_ixLoginState = LoginStates.ANONYMOUS_NOT_ALLOWED;
      }
    }

    response.contents = loginReply.encodeTag().asCompoundTag();
    return PacketResponse(replyDataTag: response.encodeTag().asCompoundTag());
  }

  @override
  Map<String, dynamic> toJson() {
    return {"user": username};
  }
}

class LoginStates {
  static const NOT_FOUND = 1;
  static const FOUND = 2;
  static const REQUIRE_MFA = 4;
  static const PROVIDE_EMAIL = 8;
  static const REQUIRE_EMAIL_CODE = 16;
  static const LOGGED_IN = 32;
  static const ANONYMOUS_NOT_ALLOWED = 64;
}

class S2CLoginReply implements IPacket {
  String username = "";
  int g_ixLoginState = 0;

  @override
  void decodeJson(String params) {
    return fromJson(json.decode(params));
  }

  @override
  void decodeTag(Tag tag) {
    CompoundTag ct = tag.asCompoundTag();
    username = ct.get("user")?.asString() ?? "";
    g_ixLoginState = ct.get("state")?.asInt() ?? 0;
  }

  @override
  NetworkDirection direction() {
    return NetworkDirection.ServerToClient;
  }

  @override
  String encodeJson() {
    return json.encode(toJson());
  }

  @override
  Tag encodeTag() {
    CompoundTag ct = CompoundTag();
    ct.put("user", StringTag.valueOf(username));
    ct.put("state", IntTag.valueOf(g_ixLoginState));

    return ct;
  }

  @override
  void fromJson(Map<String, dynamic> js) {
    username = js['user'] as String;
    g_ixLoginState = js['state'] as int;
  }

  @override
  String getChannelID() {
    return "BVSPKTLOGINREPLY";
  }

  @override
  Future<void> handleClientPacket() async {
    // do handling stuff
  }

  @override
  Future<PacketResponse> handleServerPacket() async {
    throw UnimplementedError(); // Client side only, so this never gets invoked.
  }

  @override
  Map<String, dynamic> toJson() {
    return {"user": username, "state": g_ixLoginState};
  }
}