// Copyright 2015, 2016 Parity Technologies (UK) Ltd.
// This file is part of Parity.

// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Parity.  If not, see <http://www.gnu.org/licenses/>.

import * as abis from '~/contracts/abi';
import { api } from './parity';

const sortEvents = (a, b) => b.blockNumber.cmp(a.blockNumber) || b.logIndex.cmp(a.logIndex);

const logToEvent = (log) => {
  const key = api.util.sha3(JSON.stringify(log));
  const { blockNumber, logIndex, transactionHash, transactionIndex, params, type } = log;

  return {
    type: log.event,
    state: type,
    blockNumber,
    logIndex,
    transactionHash,
    transactionIndex,
    params: Object.keys(params).reduce((data, name) => {
      data[name] = params[name].value;
      return data;
    }, {}),
    key
  };
};

export function attachInterface (callback) {
  return api.parity
    .registryAddress()
    .then((registryAddress) => {
      console.log(`the registry was found at ${registryAddress}`);

      const registry = api.newContract(abis.registry, registryAddress).instance;

      return Promise
        .all([
          registry.getAddress.call({}, [api.util.sha3('signaturereg'), 'A']),
          api.parity.accountsInfo()
        ]);
    })
    .then(([address, accountsInfo]) => {
      console.log(`signaturereg was found at ${address}`);

      const contract = api.newContract(abis.signaturereg, address);
      const accounts = Object
        .keys(accountsInfo)
        .reduce((obj, address) => {
          const info = accountsInfo[address] || {};

          return Object.assign(obj, {
            [address]: {
              address,
              name: info.name || 'Unnamed'
            }
          });
        }, {});
      const fromAddress = Object.keys(accounts)[0];

      return {
        accounts,
        address,
        accountsInfo,
        contract,
        instance: contract.instance,
        fromAddress
      };
    })
    .catch((error) => {
      console.error('attachInterface', error);
    });
}

export function attachBlockNumber (instance, callback) {
  return api.subscribe('eth_blockNumber', (error, blockNumber) => {
    if (error) {
      console.error('blockNumber', error);
      return;
    }

    instance.totalSignatures
      .call()
      .then((totalSignatures) => {
        callback({
          blockNumber,
          totalSignatures
        });
      })
      .catch((error) => {
        console.error('totalSignatures', error);
      });
  });
}

export function attachEvents (contract, callback) {
  const blocks = { '0': {} };
  let mined = [];
  let pending = [];
  let events = [];

  const options = {
    fromBlock: 0,
    toBlock: 'pending',
    limit: 50
  };

  return contract.subscribe('Registered', options, (error, _logs) => {
    if (error) {
      console.error('events', error);
      return;
    }

    const logs = _logs.map(logToEvent);

    mined = logs
      .filter((log) => log.state === 'mined')
      .map((log) => {
        const blockNumber = log.blockNumber.toString();

        if (!blocks[blockNumber]) {
          blocks[blockNumber] = {};
          getBlock(blockNumber).then((block) => {
            Object.assign(blocks[blockNumber], block);
          });
        }

        return Object.assign(log, { block: blocks[blockNumber] });
      })
      .reverse()
      .concat(mined)
      .sort(sortEvents);

    pending = logs
      .filter((log) => log.state === 'pending')
      .reverse()
      .filter((event) => !pending.find((log) => log.params.method === event.params.method))
      .concat(pending)
      .filter((event) => !mined.find((log) => log.params.method === event.params.method))
      .sort(sortEvents);

    events = pending.concat(mined);

    callback({ events });
  });
}

export function getBlock (blockNumber) {
  return api.eth.getBlockByNumber(blockNumber);
}

export function callRegister (instance, id, options = {}) {
  return instance.register.call(options, [id]);
}

export function postRegister (instance, id, options = {}) {
  return instance.register
    .estimateGas(options, [id])
    .then((gas) => {
      options.gas = gas.mul(1.2).toFixed(0);
      console.log('postRegister', `gas estimated at ${gas.toFormat(0)}, setting to ${gas.mul(1.2).toFormat(0)}`);
      instance.register.postTransaction(options, [id]);
    });
}
