#!/bin/bash

RESULTS=$1
shift
MAX_PROCESSES=$1
shift
COMMAND=$1
shift
ARGUMENTS=$@

IFS=$'\n'

FILTERED_RESULTS=()
for result in ${RESULTS[@]}
do
    [[ -z "${result//$'\n'}" ]] && continue
    FILTERED_RESULTS+=($result)
done

HOUSEKEEPING_FILE=/tmp/$$
echo -ne > $HOUSEKEEPING_FILE
i=0
for result in ${FILTERED_RESULTS[@]}
do
    (echo work for: $result; echo $ARGUMENTS $result | xargs $COMMAND; echo 1 >> $HOUSEKEEPING_FILE) &
    i=$(($i + 1))
    if [ $i -eq $MAX_PROCESSES ]
    then
        echo "MAX PROCESSES SPAWNED"
        while [ `wc -l $HOUSEKEEPING_FILE | cut -d' ' -f1` -lt $MAX_PROCESSES ]
        do
            echo "WAITING FOR PROCESS SLOT"
            sleep 1
        done
        echo -ne > $HOUSEKEEPING_FILE
        i=0
    fi
done

while [ `wc -l $HOUSEKEEPING_FILE | cut -d' ' -f1` -lt $i ]
do
    sleep 1
done

rm $HOUSEKEEPING_FILE