Shell Programming and Scripting

vidlength ()
{
    back=$(pwd)
    folder_length=
    total_folder_length=
    array=()

    # Look at the root of the folder
    # https://stackoverflow.com/a/23357277 How can I store find command result as arrays in Bash
    # $REPLY is the default variable when 'read' is not given one
    while IFS=  read -r -d $'\0'; do
        array+=("$REPLY")
    done < <(find . -maxdepth 1 \( -iname '*.mkv' -o -iname '*.mp4' -o -iname '*.avi' \) -print0)

    # exiftool -n -q -p '$Duration#' "${array[@]}" 2> /dev/null | awk '{sum += $0}; END{print sum}'                     GIVES TIME AS 78682.8
    # exiftool -n -q -p '${Duration;our $sum;$_=ConvertDuration($sum+=$_)}' "${array[@]}" 2> /dev/null| tail -n1        GIVES TIME AS 0:21:51:22
    
    # This command gives a result of '159' if the array is empty (2 minutes 39 seconds)
    total_folder_length=$(exiftool -n -q -p '$Duration#' "${array[@]}" 2> /dev/null | awk '{sum += $0}; END{print sum}') 

    # I have to add this because for wathever reason the last command fills len with the number 159 when it finds no video in the folder or when the array is empty
    if [[ "${total_folder_length%.*}" -eq 159 ]]; then
        total_folder_length=0
    fi

    counter=$(echo ${#array[@]})

    for folder in ./*; do
        #find . -maxdepth 1 \( -iname '*.mkv' -o -iname '*.mp4' -o -iname '*.avi' \)
        if [ -d "$folder" ]; then
            array=() # Empty the array between loops
            while IFS=  read -r -d $'\0'; do
                array+=("$REPLY")
            done < <(find "$folder" \( -iname '*.mkv' -o -iname '*.mp4' -o -iname '*.avi' \) -print0)
            
            # https://unix.stackexchange.com/a/170973 Way faster with exiftool
            # I have to add this because for wathever reason the last command fills len with the number 159 when it finds no video in the folder or when the array is empty
            folder_length=$(exiftool -n -q -p '$Duration#' "${array[@]}" 2> /dev/null | awk '{sum += $0}; END{print sum}')
            if [[ "${folder_length%.*}" -eq 159 ]]; then
                #len=$(echo "$len-159+$(exiftool -n -q -p '$Duration#' "${array[@]}" 2> /dev/null | awk '{sum += $0}; END{print sum}')" | bc)
                continue
            else
                total_folder_length=$(echo "$total_folder_length+$(exiftool -n -q -p '$Duration#' "${array[@]}" 2> /dev/null | awk '{sum += $0}; END{print sum}')" | bc)
            fi

            counter=$(echo $(echo ${#array[@]})+$counter | bc)
        fi
    done

    # Change it from 78682.8 to 0:21:51:22 https://unix.stackexchange.com/a/34033
    total=$(echo $total_folder_length | awk '{printf("%d:%02d:%02d:%02d\n",($1/60/60/24),($1/60/60%24),($1/60%60),($1%60))}')
    days=$(echo ${total} | awk -F ":" '{print $1}')
    hours=$(echo ${total} | awk -F ":" '{print $2}')
    minutes=$(echo ${total} | awk -F ":" '{print $3}')
    seconds=$(echo ${total} | awk -F ":" '{print $4}')

    if [[ "${days#0}" -gt 0 ]]; then
        #printf "The total duration found is:\n"
        printf "%d day(s) %02d hour(s) %02d minute(s) and %02d second(s) in %d videos\n" "${days#0}" "${hours#0}" "${minutes#0}" "${seconds#0}" "$counter"
    else
        if [[ "${hours#0}" -gt 0 ]]; then
            #printf "The total duration found is:\n"
            printf "%02d hour(s) %02d minute(s) and %02d second(s) in %d videos\n" "${hours#0}" "${minutes#0}" "${seconds#0}" "$counter"
        else
            #printf "The total duration found is:\n"
            printf "%02d minute(s) and %02d second(s) in %d videos\n" "${minutes#0}" "${seconds#0}" "$counter"
        fi
    fi

    cd "$back"
}

printf "%(%T)T\n" 78682
22:51:22

total_folder_length=$(
  find . -maxdepth 1 -type f \( -iname '*.mkv' -o -iname '*.mp4' -o -iname '*.avi' \) |
  while IFS= read -r fname 
  do
    exiftool -n -q -p '$Duration#' "$fname"
  done |
  awk '{sum+=$0} END {print sum+0}'
)

shopt -s extglob
IFS=: read DAYS HRS MIN SEC <<< $(printf "%(%j:%T)T" $(( $(cat *.@(avi|mp4|mkv) | tr '\n' '+' ) 0 )) )
echo $(( --DAYS)) $((--HRS)) $MIN $SEC
0 00 23 30