// @flow
import WalletAddressValidator from 'wallet-address-validator';
import { normalise } from './ens';
import { toChecksumAddress } from 'ethereumjs-util';
import type { RawTransaction } from 'libs/transaction';

export function isValidETHAddress(address: string): boolean {
  if (!address) {
    return false;
  }
  if (address == '0x0000000000000000000000000000000000000000') return false;
  return validateEtherAddress(address);
}

export function isValidBTCAddress(address: string): boolean {
  return WalletAddressValidator.validate(address, 'BTC');
}

export function isValidHex(str: string): boolean {
  if (typeof str !== 'string') {
    return false;
  }
  if (str === '') return true;
  str =
    str.substring(0, 2) == '0x'
      ? str.substring(2).toUpperCase()
      : str.toUpperCase();
  var re = /^[0-9A-F]+$/g;
  return re.test(str);
}

export function isValidENSorEtherAddress(address: string): boolean {
  return isValidETHAddress(address) || isValidENSAddress(address);
}

export function isValidENSName(str: string) {
  try {
    return (
      str.length > 6 && normalise(str) != '' && str.substring(0, 2) != '0x'
    );
  } catch (e) {
    return false;
  }
}

export function isValidENSAddress(address: string): boolean {
  try {
    const normalized = normalise(address);
    var tld = normalized.substr(normalized.lastIndexOf('.') + 1);
    var validTLDs = {
      eth: true,
      test: true,
      reverse: true
    };
    if (validTLDs[tld]) return true;
  } catch (e) {
    return false;
  }
  return false;
}

function isChecksumAddress(address: string): boolean {
  return address == toChecksumAddress(address);
}

// FIXME we probably want to do checksum checks sideways
function validateEtherAddress(address: string): boolean {
  if (address.substring(0, 2) != '0x') return false;
  else if (!/^(0x)?[0-9a-f]{40}$/i.test(address)) return false;
  else if (
    /^(0x)?[0-9a-f]{40}$/.test(address) ||
    /^(0x)?[0-9A-F]{40}$/.test(address)
  )
    return true;
  else return isChecksumAddress(address);
}

export function isValidPrivKey(privkey: string | Buffer): boolean {
  if (typeof privkey === 'string') {
    return privkey.length === 64;
  } else if (privkey instanceof Buffer) {
    return privkey.length === 32;
  } else {
    return false;
  }
}

export function isValidEncryptedPrivKey(privkey: string): boolean {
  if (typeof privkey === 'string') {
    return privkey.length === 128 || privkey.length === 132;
  } else {
    return false;
  }
}

export function isPositiveIntegerOrZero(number: number): boolean {
  if (isNaN(number) || !isFinite(number)) {
    return false;
  }
  return number >= 0 && parseInt(number) === number;
}

export function isValidRawTx(rawTx: RawTransaction): boolean {
  const propReqs = [
    { name: 'nonce', type: 'string', lenReq: true },
    { name: 'gasPrice', type: 'string', lenReq: true },
    { name: 'gasLimit', type: 'string', lenReq: true },
    { name: 'to', type: 'string', lenReq: true },
    { name: 'value', type: 'string', lenReq: true },
    { name: 'data', type: 'string', lenReq: false },
    { name: 'chainId', type: 'number' }
  ];

  //ensure rawTx has above properties
  //ensure all specified types match
  //ensure length !0 for strings where length is required
  //ensure valid hex for strings
  //ensure all strings begin with '0x'
  //ensure valid address for 'to' prop
  //ensure rawTx only has above properties

  for (let i = 0; i < propReqs.length; i++) {
    const prop = propReqs[i];
    const value = rawTx[prop.name];

    if (!rawTx.hasOwnProperty(prop.name)) return false;
    if (typeof value !== prop.type) return false;
    if (prop.type === 'string') {
      if (prop.lenReq && value.length === 0) return false;
      if (value.length && value.substring(0, 2) !== '0x') {
        return false;
      }
      if (!isValidHex(value)) return false;
    }
  }

  if (!isValidETHAddress(rawTx.to)) return false;
  if (Object.keys(rawTx).length !== propReqs.length) return false;

  return true;
}