Batch rename files using Vi- and friends

vimv

#!/bin/sh

# Heavily based on https://github.com/thameera/vimv,
# but ported to POSIX sh with misc. improvements
# and simplifications.

set -eu

panic() {
    echo "ERROR: $1" >&2
    exit 1
}

# Get a list of files to rename
if [ "$#" -eq 0 ]; then
    SRC=$(ls -1)
else
    SRC=$(printf "%s\n" "$@") # Expands the cmd args, using newlines
fi

SRCNO=$(printf "%s" "$SRC" | wc -l)
if [ "$SRCNO" -eq 0 ]; then
    panic "No files to rename."
fi

# Open the list of files in an editor and let the user rename files
TEMPO=$(mktemp)
# 0=exit, 1=hangup, 2=interrupt, 3=quit, 15=terminate
trap 'rm -f $TEMPO' 0 1 2 3 15
echo "$SRC" > "$TEMPO"
${EDITOR:-vi} "$TEMPO"

# Get the edited list with (possibly) new file names
DST=$(cat "$TEMPO")
DSTNO=$(printf "%s" "$DST" | wc -l)
if [ "$SRCNO" -ne "$DSTNO" ]; then
    panic "Number of files changed, aborting..."
fi

# Rename all files with new names
count="0"
while [ -n "$SRC" ]; do
    srcfile=$(echo "$SRC" | head -n 1)
    dstfile=$(echo "$DST" | head -n 1)
    SRC=$(echo "$SRC" | tail -n +2)
    DST=$(echo "$DST" | tail -n +2)

    if [ "$srcfile" = "$dstfile" ]; then
        continue
    fi

    dir=$(dirname "$dstfile")
    mkdir -p "$dir"
    mv "$srcfile" "$dstfile"
    count=$((count+1))
done
echo "$count files changed."