Migrate media from Dropbox to OneDrive

rename.sh

#!/usr/bin/env bash

# Any copyright is dedicated to the Public Domain.
# https://creativecommons.org/publicdomain/zero/1.0/

# This script was used to migrate photos and videos saved
# from Dropbox to OneDrive. Since both services use their
# own naming scheme, I wanted to maintain consistency between
# the newly uploaded files (automatically from my devices) and
# the old ones migrated from Dropbox.
# This script renames files from the Dropbox format
# (e.g. 2018-07-27 20.12.21.jpg) to OneDrive format
# (e.g. 20180727_201221.jpg). Special care was taken for duplicate
# files within the same second (e.g: 2016-07-19 07.50.07-1.mp4 for
# Dropbox and 20160719_075007_001.mp4 for OneDrive).

source_dir=$1

[ ! -d "$source_dir" ] && {
  echo "Source directory doesn't exist or isn't specified."
  exit 1
}

destination_dir=$2

[ ! -d "$destination_dir" ] && mkdir "$destination_dir"

for file in $source_dir/*; do
  basename=$(basename "$file")

  filename="${basename%.*}"
  extension="${basename##*.}"
  number=$(echo $filename | cut -d'-' -f4)

  # Replace . in filename to : so date parses the format
  replaced=${filename//\./\:}

  # Check if a sequence number is added at the end
  if [ -z "$number" ]; then
    new_date=$(date --date="$replaced" "+%Y%m%d_%H%M%S")
    new_filename=$destination_dir/$new_date.$extension
  else
    removed_number=${replaced%-*}
    new_date=$(date --date="$removed_number" "+%Y%m%d_%H%M%S")
    prepended_number=$(printf "%03d" $number)
    new_filename="$destination_dir/${new_date}_$prepended_number.$extension"
  fi

  cp -p "$file" $new_filename

  echo "Copied $file to $new_filename"
done