gather-jpegs.sh

#!/usr/bin/env bash
# gather-jpegs.sh
# Usage: ./gather-jpegs.sh /path/to/source /path/to/destination

set -euo pipefail

if [ "$#" -ne 2 ]; then
	echo "Usage: $(basename "$0") SOURCE_DIR DEST_DIR" >&2
	exit 1
fi

src=$1
dst=$2

if [ ! -d "$src" ]; then
	echo "Source directory does not exist: $src" >&2
	exit 1
fi

mkdir -p "$dst"

export LC_ALL=C

# Find all JPEGs (case-insensitive), then copy with organized structure.
find "$src" -type f \( -iname '*.jpg' -o -iname '*.jpeg' \) -print0 |
	while IFS= read -r -d '' f; do
		base=$(basename "$f")
		name=${base%.*}
		ext=${base##*.}

		# Parse filename format: timestamp-titleID.ext
		if [[ "$name" =~ ^([0-9]+)-([0-9A-F]+)$ ]]; then
			timestamp="${BASH_REMATCH[1]}"
			title_id="${BASH_REMATCH[2]}"

			# Create subfolder for this title ID
			title_dir="$dst/$title_id"
			mkdir -p "$title_dir"

			# Target filename is just the timestamp
			target="$title_dir/$timestamp.$ext"

			# If a file with the same timestamp already exists, add a number suffix
			if [ -e "$target" ]; then
				i=1
				target="$title_dir/${timestamp}_${i}.$ext"
				while [ -e "$target" ]; do
					i=$((i + 1))
					target="$title_dir/${timestamp}_${i}.$ext"
				done
			fi
		else
			# Fallback for files that don't match the expected format
			echo "Warning: File doesn't match expected format (timestamp-titleID): $base"
			target="$dst/$base"

			# If a file with the same name already exists, make a unique target name.
			if [ -e "$target" ]; then
				i=1
				target="$dst/${name}_${i}.${ext}"
				while [ -e "$target" ]; do
					i=$((i + 1))
					target="$dst/${name}_${i}.${ext}"
				done
			fi
		fi

		# -p preserves timestamps and mode; add -n to avoid overwrite, but we already ensure uniqueness.
		cp -p "$f" "$target"
		echo "Copied: $target"
	done

echo "Done."