#!/bin/sh

set -eu

if [ "$#" -lt 1 ] || [ "$#" -gt 2 ]; then
    printf 'Usage: %s INPUT.csv [OUTPUT.csv]\n' "$0" >&2
    exit 2
fi

input=$1
output=${2:--}

process_csv() {
    awk -F '\",\"' '
    BEGIN {
        OFS = FS
    }

    {
        sub(/\r$/, "", $0)
    }

    NR == 1 {
        print
        next
    }

    {
        if ($5 == "-  -") {
            $5 = ""
        }

        print
    }
' "$input"
}

if [ "$output" = "-" ]; then
    process_csv
else
    process_csv > "$output"
fi