/*  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 { Secp256k1HdWallet } from '@cosmjs/amino';
import { AccountData } from '@cosmjs/proto-signing';
import { stringToPath } from '@cosmjs/crypto';

import { Account, WalletDetails } from '../types';
import {
  getHDPath,
  getPathKey,
  resetKeyServers,
  updateGlobalCounter,
} from './misc';

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 id = await getNextAccountId(network);
    const hdPath = getHDPath(network, `0'/0/${id}`);
    const accounts = await addAccountFromHDPath(hdPath);
    await updateAccountIndices(network, id);
    return accounts;
  } 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;
  }
};

const accountInfoFromHDPath = async (
  hdPath: string,
): Promise<
  | { privKey: string; pubKey: string; address: string; network: string }
  | undefined
> => {
  const mnemonicStore = await getInternetCredentials('mnemonicServer');
  if (!mnemonicStore) {
    throw new Error('Mnemonic not found!');
  }

  const mnemonic = mnemonicStore.password;
  const hdNode = HDNode.fromMnemonic(mnemonic);
  const node = hdNode.derivePath(hdPath);

  const privKey = node.privateKey;
  const pubKey = node.publicKey;

  const parts = hdPath.split('/');
  const path = parts.slice(-3).join('/');
  const coinType = parts[2];

  let network: string;
  let address: string;

  switch (coinType) {
    case "60'":
      network = 'eth';
      address = node.address;
      break;
    case "118'":
      network = 'cosmos';
      address = (await getCosmosAccounts(mnemonic, path)).data.address;
      break;
    default:
      throw new Error('Invalid wallet type');
  }
  return { privKey, pubKey, address, network };
};

const getNextAccountId = async (network: string): Promise<number> => {
  const idStore = await getInternetCredentials(`${network}:accountIndices`);
  if (!idStore) {
    throw new Error('Account id not found');
  }

  const accountIds = idStore.password;
  const ids = accountIds.split(',').map(Number);
  return ids[ids.length - 1] + 1;
};

const updateAccountIndices = async (
  network: string,
  id: number,
): Promise<void> => {
  const idStore = await getInternetCredentials(`${network}:accountIndices`);
  if (!idStore) {
    throw new Error('Account id not found');
  }

  const updatedIndices = `${idStore.password},${id.toString()}`;
  await resetInternetCredentials(`${network}:accountIndices`);
  await setInternetCredentials(
    `${network}:accountIndices`,
    `${network}Counter`,
    updatedIndices,
  );
};

const getCosmosAccounts = async (
  mnemonic: string,
  path: string,
): Promise<{ cosmosWallet: Secp256k1HdWallet; data: AccountData }> => {
  const cosmosWallet = await Secp256k1HdWallet.fromMnemonic(mnemonic, {
    hdPaths: [stringToPath(`m/44'/118'/${path}`)],
  });

  const accountsData = await cosmosWallet.getAccounts();
  const data = accountsData[0];

  return { cosmosWallet, data };
};

export {
  createWallet,
  addAccount,
  addAccountFromHDPath,
  retrieveAccounts,
  retrieveSingleAccount,
  resetWallet,
  accountInfoFromHDPath,
  getNextAccountId,
  updateAccountIndices,
  getCosmosAccounts,
};