mtimer

#!/bin/bash 

# These MUST be a command that returns a single number in each of these:
STARTCMD="sudo fdisk -l /dev/sdb | grep Disk | head -1 | awk '{print \$5}'"
UPDATECMD="ls -l openelec_04-03-2015.img | cut -d\" \" -f5"
# Other options:
#   STARTCMD="df | grep '/exports/media' | awk '{print \$3}'"
#   UPDATECMD="df | grep /raid | awk '{print \$3}'"
#   STARTCMD="stat -cs \$FILE"
#   UPDATECMD="stat -cb \$FILE"
CALC=$(which calc)

if [ -z $CALC ] ; then
    echo -n "calc not found. Would you like to install it? (Y,n)"
    read INPUT
    if [ $INPUT = 'n' ] || [ $INPUT = 'N' ] ; then
        echo "exiting"
        exit 1
    else
        sudo apt install apcalc
    fi
fi

# change the metric to whatever is relevant.
METRIC="b"

# can specify an output file. Usually if you want it to run in the background
# and then use "watch cat outputfile" to check on progress.
# if empty, output goes to the screen
#OUTPUT="outputfile.txt"
OUTPUT=""


# all the rest should take care of itself.
output() {
    if [ -z $OUTPUT ]; then
       echo "$*"
   else
      echo "$*" >> $OUTPUT
  fi
} 

clearscreen() {
    if [ -z $OUTPUT ] ; then
        clear
    else
        echo "" > $OUTPUT
    fi
}



humanise() {
    if [ -z $1 ]; then
        return 1
    fi

    local SECS=$1
    local ETA=""

    if [ $SECS -gt 604800 ]; then
        local WEEKS=$($CALC -p $SECS \/ 604800 | sed 's/~//g'|cut -d. -f1)
        SECS=$($CALC $SECS - \($WEEKS \* 604800\))
        ETA="$WEEKS w, "
    fi

    if [ $SECS -gt 86400 ]; then
        local DAYS=$($CALC -p $SECS \/ 86400 | sed 's/~//g'|cut -d. -f1)
        SECS=$($CALC $SECS - \($DAYS \* 86400\))
        if [ $DAYS -le 9 ] ; then
            DAYS="00$DAYS"
        fi
        ETA="$ETA$DAYS d, "
    elif ! [ -z "$ETA" ] ; then
       ETA="${ETA}0 d, " 
    fi

    if [ $SECS -gt 3600 ]; then
        local HOURS=$($CALC -p $SECS \/ 3600 | sed 's/~//g'|cut -d. -f1)
        SECS=$($CALC $SECS - \($HOURS \* 3600\))
        if [ $HOURS -le 9 ] ; then
            HOURS="0$HOURS"
        fi
        ETA="$ETA$HOURS h, "
    elif ! [ -z "$ETA" ] ; then
       ETA="${ETA}00 h, " 
    fi

    if [ $SECS -gt 60 ]; then
        local MINS=$($CALC -p $SECS \/ 60 | sed 's/~//g'|cut -d. -f1)
        SECS=$($CALC $SECS - \($MINS \* 60\))
        if [ $MINS -le 9 ] ; then
            MINS="0$MINS"
        fi
        ETA="$ETA$MINS m, "
    elif ! [ -z "$ETA" ] ; then
       ETA="${ETA}00 m, " 
    fi

    SECS=$(echo $SECS |awk '{print $1}') 
    if [ $SECS -le 9 ] ; then
        SECS="0$SECS"
    fi
    ETA="$ETA$SECS s"

    echo $ETA
    return
}

if [ $# -eq 1 ] ; then
    FILE=$1
fi

STARTTIME=$(date +%s)
TARGETSIZE=$(sh -c "$STARTCMD")
STARTSIZE=$(sh -c "$UPDATECMD")
CURRENTSIZE=0

while [ $CURRENTSIZE -lt $TARGETSIZE ]; do
    sleep 2
    NOW=$(date +%s)
    CURRENTSIZE=$(sh -c "$UPDATECMD")
    ELAPSEDTIME=$($CALC $NOW - $STARTTIME)
    AMOUNTTOGO=$($CALC $TARGETSIZE - $CURRENTSIZE)
    GROWTH=$($CALC $CURRENTSIZE - $STARTSIZE)
    RATE=$($CALC -p $GROWTH \/ $ELAPSEDTIME | sed 's/~//g' | cut -d. -f1)
    TIMETOGO=$($CALC -p $AMOUNTTOGO \/ $RATE | sed 's/~//g'|cut -d. -f1)
    ESTCOMPLETIONTIME=$($CALC $NOW + $TIMETOGO | awk '{print $1}')
    ETA=$(humanise $TIMETOGO)
    EST=$(date --date="@$ESTCOMPLETIONTIME" '+%d %b %Y %H:%M:%S')
    clearscreen
    output "Target size:    $TARGETSIZE $METRIC "
    output "Current size:   $CURRENTSIZE $METRIC"
    output "Amount to go: $AMOUNTTOGO $METRIC"
    output "Rate:           $RATE $METRIC/s"
    output ""
    output "Time to go: $ETA"
    output "ETA: $EST"
done