// Copyright 2015-2017 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 { uniq } from 'lodash';

import Contracts from '~/contracts';
import { LOG_KEYS, getLogger } from '~/config';
import { IconCache } from '~/ui';
import { fetchTokenIds, fetchTokenInfo } from '~/util/tokens';

import { updateTokensFilter } from './balancesActions';

const log = getLogger(LOG_KEYS.Balances);

export function setTokens (tokens) {
  return {
    type: 'setTokens',
    tokens
  };
}

export function loadTokens (options = {}) {
  log.debug('loading tokens', Object.keys(options).length ? options : '');

  return (dispatch, getState) => {
    const { api } = getState();
    const { tokenReg } = Contracts.get(api);

    tokenReg.getInstance()
      .then((tokenRegInstance) => {
        return fetchTokenIds(tokenRegInstance);
      })
      .then((tokenIndexes) => dispatch(fetchTokens(tokenIndexes, options)))
      .catch((error) => {
        console.warn('tokens::loadTokens', error);
      });
  };
}

export function fetchTokens (_tokenIndexes, options = {}) {
  const tokenIndexes = uniq(_tokenIndexes || []);

  return (dispatch, getState) => {
    const { api } = getState();
    const { tokenReg } = Contracts.get(api);
    const iconCache = IconCache.get();

    return tokenReg.getInstance()
      .then((tokenRegInstance) => {
        const promises = tokenIndexes.map((id) => fetchTokenInfo(api, tokenRegInstance, id));

        return Promise.all(promises);
      })
      .then((results) => {
        const tokens = results
          .reduce((tokens, token) => {
            const { id, image, address } = token;

            // dispatch only the changed images
            if (iconCache.images[address] !== image) {
              iconCache.add(address, image, true);
            }

            tokens[id] = token;
            return tokens;
          }, {});

        log.debug('fetched token', tokens);

        dispatch(setTokens(tokens));
        dispatch(updateTokensFilter(null, null, options));
      })
      .catch((error) => {
        console.warn('tokens::fetchTokens', error);
      });
  };
}