#!/bin/sh
[ -z "$1" ] && printf "Usage: rename_image.sh <directory>\n" && exit 2;

chop() {
    local S="$1" # no. of characters to chop
    local L="$2" # full text
    local COLS=$(tput cols)
    local C=$(($COLS-$S))
    printf '%s' "$L" | awk -vC="$C" \
        '{ line=substr($0,length($0)-C,C+1) }
         { if (length($0) > C) print "..."line; else print $0 }'
}

find "$1" -type f -iname "*.cr2" -o -iname "*.crw" -o -iname "*.nef" \
               -o -iname "*.dng" \
| while read L;
do  
    F="${L##*/}"
    if printf '%s' "$F" | grep -qE "^[0-9]{8}_[0-9]{6}_.*"; then
        printf '%s\n' "↷ Skipping: $(chop "16" "$L")"
    else
        if exiv2 -r'%Y%m%d_%H%M%S_(:basename:)' rename "$L" \
            > /dev/null 2>&1; then
            printf '%s\n' "✓ Renaming: $(chop "16" "$L")"
        else
            printf '%s\n' "↯ Failed: $(chop "14" "$L")"
        fi
    fi
done