/*  Importing this library provides react native with a secure random source.
For more information, "visit https://docs.ethers.org/v5/cookbook/react-native/#cookbook-reactnative-security" */
import 'react-native-get-random-values';
import '@ethersproject/shims';

import { utils } from 'ethers';
import { HDNode } from 'ethers/lib/utils';
import {
  setInternetCredentials,
  resetInternetCredentials,
  getInternetCredentials,
} from 'react-native-keychain';

import { Account, WalletDetails } from '../types';
import {
  accountInfoFromHDPath,
  getAddress,
  getCosmosAccounts,
  getHDPath,
  getMnemonic,
  getNextAccountId,
  getPathKey,
  resetKeyServers,
  updateAccountIndices,
  updateGlobalCounter,
} from './utils';

const createWallet = async (): Promise<WalletDetails> => {
  try {
    const mnemonic = utils.entropyToMnemonic(utils.randomBytes(16));
    await setInternetCredentials('mnemonicServer', 'mnemonic', mnemonic);

    const hdNode = HDNode.fromMnemonic(mnemonic);
    const ethNode = hdNode.derivePath("m/44'/60'/0'/0/0");
    const cosmosNode = hdNode.derivePath("m/44'/118'/0'/0/0");

    const ethAddress = ethNode.address;
    const cosmosAddress = (await getCosmosAccounts(mnemonic, "0'/0/0")).data
      .address;

    const ethAccountInfo = `${"0'/0/0"},${ethNode.privateKey},${
      ethNode.publicKey
    },${ethAddress}`;
    const cosmosAccountInfo = `${"0'/0/0"},${cosmosNode.privateKey},${
      cosmosNode.publicKey
    },${cosmosAddress}`;

    await Promise.all([
      setInternetCredentials(
        'eth:keyServer:0',
        'eth:pathKey:0',
        ethAccountInfo,
      ),
      setInternetCredentials(
        'cosmos:keyServer:0',
        'cosmos:pathKey:0',
        cosmosAccountInfo,
      ),
      setInternetCredentials('eth:accountIndices', 'ethCounter', '0'),
      setInternetCredentials('cosmos:accountIndices', 'cosmosCounter', '0'),
      setInternetCredentials('eth:globalCounter', 'ethGlobal', '0'),
      setInternetCredentials('cosmos:globalCounter', 'cosmosGlobal', '0'),
    ]);

    const ethAccounts = {
      counterId: 0,
      pubKey: ethNode.publicKey,
      address: ethAddress,
      hdPath: "m/44'/60'/0'/0/0",
    };

    const cosmosAccounts = {
      counterId: 0,
      pubKey: cosmosNode.publicKey,
      address: cosmosAddress,
      hdPath: "m/44'/118'/0'/0/0",
    };

    return { mnemonic, ethAccounts, cosmosAccounts };
  } catch (error) {
    console.error('Error creating HD wallet:', error);
    return { mnemonic: '', ethAccounts: undefined, cosmosAccounts: undefined };
  }
};

const addAccount = async (network: string): Promise<Account | undefined> => {
  try {
    const mnemonic = await getMnemonic();
    const hdNode = HDNode.fromMnemonic(mnemonic);
    const id = await getNextAccountId(network);
    const hdPath = getHDPath(network, `0'/0/${id}`);

    const node = hdNode.derivePath(hdPath);
    const pubKey = node.publicKey;
    const address = await getAddress(network, mnemonic, `0'/0/${id}`);

    await updateAccountIndices(network, id);
    const { counterId } = await updateGlobalCounter(network);

    await Promise.all([
      setInternetCredentials(
        `${network}:keyServer:${counterId}`,
        `${network}:pathKey:${counterId}`,
        `0'/0/${id},${node.privateKey},${node.publicKey},${address}`,
      ),
    ]);

    return { counterId, pubKey, address, hdPath };
  } catch (error) {
    console.error('Error creating account:', error);
  }
};

const addAccountFromHDPath = async (
  hdPath: string,
): Promise<Account | undefined> => {
  try {
    const account = await accountInfoFromHDPath(hdPath);
    if (!account) {
      throw new Error('Error while creating account');
    }

    const parts = hdPath.split('/');
    const path = parts.slice(-3).join('/');

    const { privKey, pubKey, address, network } = account;

    const counterId = (await updateGlobalCounter(network)).counterId;

    await Promise.all([
      setInternetCredentials(
        `${network}:keyServer:${counterId}`,
        `${network}:pathKey:${counterId}`,
        `${path},${privKey},${pubKey},${address}`,
      ),
    ]);

    return { counterId, pubKey, address, hdPath };
  } catch (error) {
    console.error(error);
  }
};

const retrieveAccountsForNetwork = async (
  network: string,
  count: string,
): Promise<Account[]> => {
  const elementsArray = count.split(',');

  const loadedAccounts = await Promise.all(
    elementsArray.map(async i => {
      const pubKey = (await getPathKey(network, Number(i))).pubKey;
      const address = (await getPathKey(network, Number(i))).address;
      const path = (await getPathKey(network, Number(i))).path;
      const hdPath = getHDPath(network, path);

      const account: Account = {
        counterId: Number(i),
        pubKey: pubKey,
        address: address,
        hdPath: hdPath,
      };
      return account;
    }),
  );

  return loadedAccounts;
};

const retrieveAccounts = async (): Promise<{
  ethLoadedAccounts?: Account[];
  cosmosLoadedAccounts?: Account[];
}> => {
  const ethServer = await getInternetCredentials('eth:globalCounter');
  const ethCounter = ethServer && ethServer.password;
  const cosmosServer = await getInternetCredentials('cosmos:globalCounter');
  const cosmosCounter = cosmosServer && cosmosServer.password;

  const ethLoadedAccounts = ethCounter
    ? await retrieveAccountsForNetwork('eth', ethCounter)
    : undefined;
  const cosmosLoadedAccounts = cosmosCounter
    ? await retrieveAccountsForNetwork('cosmos', cosmosCounter)
    : undefined;

  return { ethLoadedAccounts, cosmosLoadedAccounts };
};

const retrieveSingleAccount = async (network: string, address: string) => {
  let loadedAccounts;

  switch (network) {
    case 'eth':
      const ethServer = await getInternetCredentials('eth:globalCounter');
      const ethCounter = ethServer && ethServer.password;

      if (ethCounter) {
        loadedAccounts = await retrieveAccountsForNetwork(network, ethCounter);
      }
      break;

    case 'cosmos':
      const cosmosServer = await getInternetCredentials('cosmos:globalCounter');
      const cosmosCounter = cosmosServer && cosmosServer.password;

      if (cosmosCounter) {
        loadedAccounts = await retrieveAccountsForNetwork(
          network,
          cosmosCounter,
        );
      }
      break;

    default:
      break;
  }

  if (loadedAccounts) {
    return loadedAccounts.find(account => account.address === address);
  }

  return undefined;
};

const resetWallet = async () => {
  try {
    await Promise.all([
      resetInternetCredentials('mnemonicServer'),
      resetKeyServers('eth'),
      resetKeyServers('cosmos'),
      resetInternetCredentials('eth:accountIndices'),
      resetInternetCredentials('cosmos:accountIndices'),
      resetInternetCredentials('eth:globalCounter'),
      resetInternetCredentials('cosmos:globalCounter'),
    ]);
  } catch (error) {
    console.error('Error resetting wallet:', error);
    throw error;
  }
};

export {
  createWallet,
  addAccount,
  addAccountFromHDPath,
  retrieveAccounts,
  retrieveSingleAccount,
  resetWallet,
};