import 'dart:async';
import 'dart:convert';

import 'package:cw_core/crypto_currency.dart';
import 'package:cw_zano/api/calls.dart' as calls;
import 'package:cw_zano/api/model/get_wallet_info_result.dart';
import 'package:cw_zano/api/model/get_wallet_status_result.dart';
import 'package:cw_zano/api/model/zano_wallet_keys.dart';
import 'package:cw_zano/zano_balance.dart';
import 'package:cw_zano/zano_wallet.dart';
import 'package:flutter/foundation.dart';
import 'package:mobx/mobx.dart' as mobx;

int getCurrentHeight(int hWallet) {
  final json = calls.getWalletStatus(hWallet);
  final walletStatus = GetWalletStatusResult.fromJson(jsonDecode(json) as Map<String, dynamic>);
  return walletStatus.currentWalletHeight;
}

int getNodeHeightSync(int hWallet) {
  final json = calls.getWalletStatus(hWallet);
  final walletStatus = GetWalletStatusResult.fromJson(jsonDecode(json) as Map<String, dynamic>);
  return walletStatus.currentDaemonHeight;
}

class SyncListener {
  SyncListener(this.onNewBlock, this.onNewTransaction)
      : _cachedBlockchainHeight = 0,
        _lastKnownBlockHeight = 0,
        _initialSyncHeight = 0;

  void Function(int, int, double) onNewBlock;
  void Function() onNewTransaction;

  Timer? _updateSyncInfoTimer;
  int _cachedBlockchainHeight;
  int _lastKnownBlockHeight;
  int _initialSyncHeight;

  Future<int> getNodeHeightOrUpdate(int hWallet, int baseHeight) async {
    if (_cachedBlockchainHeight < baseHeight || _cachedBlockchainHeight == 0) {
      _cachedBlockchainHeight = await compute<int, int>(getNodeHeightSync, hWallet);
    }

    return _cachedBlockchainHeight;
  }

  void start(ZanoWalletBase wallet, int hWallet) async {
    _cachedBlockchainHeight = 0;
    _lastKnownBlockHeight = 0;
    _initialSyncHeight = 0;
    _updateSyncInfoTimer ??= Timer.periodic(Duration(milliseconds: 1200), (_) async {
      /**if (isNewTransactionExist()) {
        onNewTransaction?.call();
      }*/

      var syncHeight = getCurrentHeight(hWallet);

      final json = calls.getWalletInfo(hWallet);
      final result = GetWalletInfoResult.fromJson(jsonDecode(json) as Map<String, dynamic>);
      wallet.seed = result.wiExtended.seed;
      wallet.keys = ZanoWalletKeys(
        privateSpendKey: result.wiExtended.spendPrivateKey,
        privateViewKey: result.wiExtended.viewPrivateKey,
        publicSpendKey: result.wiExtended.spendPublicKey,
        publicViewKey: result.wiExtended.viewPublicKey,
      );

      final balance = result.wi.balances.first;
      wallet.assetId = balance.assetInfo.assetId;
      wallet.balance = mobx.ObservableMap.of(
          {CryptoCurrency.zano: ZanoBalance(total: balance.total, unlocked: balance.unlocked)});

      if (_initialSyncHeight <= 0) {
        _initialSyncHeight = syncHeight;
      }

      final bchHeight = await getNodeHeightOrUpdate(hWallet, syncHeight);

      if (_lastKnownBlockHeight == syncHeight || syncHeight == null) {
        return;
      }

      _lastKnownBlockHeight = syncHeight;
      final track = bchHeight - _initialSyncHeight;
      final diff = track - (bchHeight - syncHeight);
      final ptc = diff <= 0 ? 0.0 : diff / track;
      final left = bchHeight - syncHeight;

      if (syncHeight < 0 || left < 0) {
        return;
      }

      // 1. Actual new height; 2. Blocks left to finish; 3. Progress in percents;
      onNewBlock?.call(syncHeight, left, ptc);
    });
  }

  void stop() => _updateSyncInfoTimer?.cancel();
}

SyncListener setListeners(
    void Function(int, int, double) onNewBlock, void Function() onNewTransaction) {
  final listener = SyncListener(onNewBlock, onNewTransaction);
  /**setListenerNative();*/
  return listener;
}