#!/bin/bash
#  $HeadURL$ $LastChangedRevision$
set -e
PROGNAME=$(basename $0)

#  Load support functions
. $(pcms-config PCMS_SHARE_PREFIX)/scripts/support.sh

main()
{
    #  Defaults for options
    VERBOSELEVEL=2
    OPT_TIMEOUT=5

    #  Process options
    while [ $# -ge 1 ]; do
        case $1 in
            --timeout=*)     OPT_TIMEOUT=${1#*=} ;;
            --debug=*)       VERBOSELEVEL=${1#*=} ;;
            -d)              VERBOSELEVEL=$2; shift ;;
            -v|--verbose)    VERBOSELEVEL=3 ;;
            --)              shift; break ;;
            -*)              error "main: $1: bad option" ;;
            *)               break ;;
        esac
        shift
    done

    #  Process arguments
    [ $# -ge 1 ] || usage

    #  Guts
    ALL_OK=true
    for CMDLINE_ARG in "$@"; do
        case $CMDLINE_ARG in
            gateway)  TARGET_HOSTNAMES=( $(ip -4 -o route | sed -nr 's/default via (.*) dev .*/\1/p') ) ;;
            internet) TARGET_HOSTNAMES=( 8.8.8.8 www.de ) ;;
            repos)    TARGET_HOSTNAMES=( $(sed -nr 's/^deb https?:\/\/([^ /]+).*/\1/p' /etc/apt/sources.list /etc/apt/sources.list.d/* 2>/dev/null | sort -u | paste -d' ' -s) ) ;;
            *)        TARGET_HOSTNAMES=( $CMDLINE_ARG ) ;;
        esac
        for TARGET_HOSTNAME in "${TARGET_HOSTNAMES[@]}"; do
            debug 10 "$TARGET_HOSTNAME: checking ..."
            STOP_TIMESTAMP=$(($(date +%s) + $OPT_TIMEOUT))
            while :; do
                NOW_TIMESTAMP=$(date +%s)
                debug 10 "main: NOW_TIMESTAMP=$NOW_TIMESTAMP, STOP_TIMESTAMP=$STOP_TIMESTAMP"
                if ping -c 1 -w 0.2 $TARGET_HOSTNAME > /dev/null 2>/dev/null; then
                    OK=true
                    break
                fi
                if (($NOW_TIMESTAMP >= $STOP_TIMESTAMP)); then
                    OK=false
                    break
                fi
            done
            $OK || { ALL_OK=false; break 2; }
        done
    done
    #  CMDLINE_ARG will still contain the last failed hostname or alias, so we
    #  can use it in an error message.
    $ALL_OK || error "$CMDLINE_ARG: not reachable or resolution problem (depending how caller handles this, it may be okay)"
}

usage() { echo "Usage: $PROGNAME [ --timeout=<secs> ] { gateway | repos | internet | <host> } ..." >&2; exit 1; }

main "$@"