#!/usr/bin/env bash

show_help() {
	cat <<-EOF
        Usage: $(basename "$0") [OPTIONS] <ROOT_DIR> <DATE> [COMMAND...]
        Finds directories inside ROOT_DIR that were modified before DATE
        and executes provided COMMAND inside each of them.

        Just lists directories if COMMAND is not provied.

        Options:
          -h            Show help
          -v            Verbose output

        DATE formats:
          Accepts any date format understood by the 'date' command.
          Examples:
            2025-10-05
            "2025-10-05 12:00"
            "Oct 5 2025"
            "yesterday"
            "2 weeks ago"

        Examples:
          $(basename "$0") /var/log 2025-10-05
          $(basename "$0") /tmp "2025-10-05 18:00" pwd 
	EOF
}

VERBOSE=0

while getopts "hv" opt; do
        case $opt in
                h)
                        show_help
                        exit 0
                        ;;
                v)
                        VERBOSE=1
                        ;;
                *)
                        echo "Unknown arguments, use -h for help."
                        exit 1
                        ;;
        esac
done
shift $((OPTIND - 1))

show_error() {
        echo $* >&2
        echo "Use -h for help..."
}

log() {
        if [[ "$VERBOSE" -eq 1 ]]; then
                echo $*
        fi
}

MIN_ARGS=2
if [ $# -lt $MIN_ARGS ]; then
        show_error "Not enough arguments! Expected $MIN_ARGS, got $#"
        exit 2
fi

ROOT_DIR="$1"
DATE_STR="$2"

if [[ ! -d "$ROOT_DIR" ]]; then
        show_error "Provided ROOT_DIR (\"$ROOT_DIR\") does not exist!"
        exit 2
fi
log "Provided ROOT_DIR: $ROOT_DIR"

if ! date -d "$DATE_STR" >/dev/null 2>&1; then
    show_error "Invalid date!"
    exit 2
fi
DATE=$(date -d "$DATE_STR" +%FT%T)
log "Provided DATE: $DATE_STR"
log "Parsed date: $DATE"

shift 2
COMMAND="$*"
log "Provided COMMAND: $COMMAND"


FIND_CMD=(find "$ROOT_DIR" -type d ! -newermt "$DATE")

if [[ -n "$COMMAND" ]]; then
  #FIND_CMD+=(-exec $COMMAND \;)
  FIND_CMD+=(-exec bash -c "cd '{}' && $COMMAND" \;)
fi

log "Final command: ${FIND_CMD[*]}"
"${FIND_CMD[@]}"