#!/usr/bin/env bash

function datemv {
    if [[ $(basename "$1") == $(stat -c "%y" "$1" | cut -d " " -f1)* ]]; then
        echo "Do nothing with '$1'"
    else
        mv -v "$1" "$(dirname "$1")/$(stat -c "%y" "$1" | cut -d " " -f1)_$(basename "$1")"
    fi
}

if [ -d $1 ]; then
    for file in $(find "$1" -type f | grep -vP "\/\d{4}-\d{2}-\d{2}"); do
        datemv "$file"
    done
else
    echo "Directory not found '$1'"
    exit
fi