lbry-desktop/ui/js/actions/cost_info.js

import * as types from 'constants/action_types'
import lbry from 'lbry'
import lbryio from 'lbryio'
import {
  doResolveUri
} from 'actions/content'
import {
  selectResolvingUris,
} from 'selectors/content'
import {
  selectClaimsByUri
} from 'selectors/claims'
import {
  selectSettingsIsGenerous
} from 'selectors/settings'

export function doFetchCostInfoForUri(uri) {
  return function(dispatch, getState) {
    const state = getState(),
          claim = selectClaimsByUri(state)[uri],
          isResolving = selectResolvingUris(state).indexOf(uri) !== -1,
          isGenerous = selectSettingsIsGenerous(state)

    if (claim === null) { //claim doesn't exist, nothing to fetch a cost for
      return
    }

    if (!claim) {
      setTimeout(() => {
        dispatch(doFetchCostInfoForUri(uri))
      }, 1000)
      if (!isResolving) {
        dispatch(doResolveUri(uri))
      }
      return
    }


    function begin() {
      dispatch({
        type: types.FETCH_COST_INFO_STARTED,
        data: {
          uri,
        }
      })
    }

    function resolve(costInfo) {
      dispatch({
        type: types.FETCH_COST_INFO_COMPLETED,
        data: {
          uri,
          costInfo,
        }
      })
    }

    if (isGenerous && claim) {
      let cost
      const fee = claim.value.stream.metadata.fee;
      if (fee === undefined ) {
        resolve({ cost: 0, includesData: true })
      } else if (fee.currency == 'LBC') {
        resolve({ cost: fee.amount, includesData: true })
      } else {
        begin()
        lbryio.getExchangeRates().then(({lbc_usd}) => {
          resolve({ cost: fee.amount / lbc_usd, includesData: true })
        });
      }
    } else {
      begin()
      lbry.getCostInfo(uri).then(resolve)
    }
  }
}