tpdfc

#!/usr/bin/env bash

# this is a script for controlling running instances of termpdf

function help(){
    echo "$(basename $0) usage:"
    echo "    $(basename $0) <option> <termpdf command>"
    echo "    options:"
    echo "       -n N    if there is more than one instance of termpdf"
    echo "               running, communicate with the Nth instance."
    echo "               (As ordered by pgrep -f termpdf)"
    echo "       -p PID  communicate with the instance of termpdf with"
    echo "               the specified PID"
    echo "       -l      list all running instances of termpdf"
    echo "       -h      see this help"
    echo
    echo "    <termpdf command> can be any command available from the"
    echo "    command mode within termpdf. E.g., 'goto 5' will flip to"
    echo "    page 5."
}

function list_instances(){
    echo "N PID FILE"
    pgrep -l -f termpdf | cat -n | awk '{print $1,$2,$5}' | column -t
}

n=1

if [[ "$1" == "-h" || "$1" == "--help" || $# -eq 0 ]]; then
    help
    exit
fi

if ! pgrep -f termpdf &>/dev/null ; then
    echo "No instances of termpdf to control."
    exit
fi

if [[ "$1" == "-l" ]]; then
    list_instances
    exit
fi

if [[ "$1" == '-n' ]]; then
    shift
    if [[ "$1" =~ ^[0-9]+$ ]]; then
        n="$1"
        shift
    else
        help
        exit 1
    fi
fi

if [[ "$1" == '-p' ]]; then
    shift
    if [[ "$1" =~ ^[0-9]+$ ]]; then
        termpdfPID="$1"
        shift
    else
        help
        exit 1
    fi
else
    termpdfPID=$(pgrep -f termpdf | sed $n'q;d')
    if [[ $termpdfPID == "" ]]; then
        echo "No instance $n of termpdf to control."
        list_instances
    fi
fi

signal_file="$HOME/.config/termpdf/sigusr1"
echo "$@" > "$signal_file"
kill -SIGUSR1 $termpdfPID