shellfu-bash-saturnin/bin/saturnin-czrates

#!/bin/bash

. <(ffoom init)

ffoo import core

uri='https://www.cnb.cz/en/financial_markets/foreign_exchange_market/exchange_rate_fixing/daily.txt'

get_field() {
    local wntcur=$1
    local wntfld=${2:-Rate}
    local fldn
    case "$wntfld" in
        Country|Currency|Amount|Code|Rate) true;;
        *) usage_is "code Country|Currency|Amount|Code|Rate" ;;
    esac
    local date head
    read date
    read head
    IFS='|'; while read Country Currency Amount Code Rate;
    do
        test "$wntcur" = "$Code" && echo ${!wntfld}
    done
}

curl --insecure --silent "$uri" \
  | get_field ${1:-USD} Rate