Case Statements for Pattern Matching

#!/usr/bin/env bash
set -euo pipefail

classify_file() {
    local file=$1
    case "$file" in
        *.jpg|*.jpeg|*.png|*.gif|*.webp)
            echo "Image file: $file" ;;
        *.mp3|*.wav|*.flac|*.ogg)
            echo "Audio file: $file" ;;
        *.mp4|*.avi|*.mkv|*.webm)
            echo "Video file: $file" ;;
        *.txt|*.md|*.rst)
            echo "Text file: $file" ;;
        *.sh|*.bash)
            echo "Shell script: $file" ;;
        *.tar|*.gz|*.zip|*.bz2)
            echo "Archive: $file" ;;
        *)
            echo "Unknown type: $file" ;;
    esac
}

dispatch() {
    local command=$1
    shift
    case "$command" in
        start|up)
            echo "Starting service: $*"
            ;;
        stop|down)
            echo "Stopping service: $*"
            ;;
        restart|reload)
            echo "Restarting service: $*"
            ;;
        status)
            echo "Checking status: $*"
            ;;
        -h|--help|help)
            echo "Usage: $0 {start|stop|restart|status}"
            ;;
        *)
            echo "Unknown command: $command" >&2
            echo "Use --help for usage" >&2
            return 1
            ;;
    esac
}

parse_input() {
    local input=$1
    case "$input" in
        [0-9]*)
            echo "Starts with number" ;;
        [a-z]*)
            echo "Starts with lowercase" ;;
        [A-Z]*)
            echo "Starts with uppercase" ;;
        -*)
            echo "Starts with dash (option)" ;;
        *)
            echo "Other: $input" ;;
    esac
}

classify_file "photo.jpg"
classify_file "script.sh"
classify_file "unknown.xyz"

dispatch start "my-service"
dispatch status "my-service"

parse_input "123abc"
parse_input "hello"
parse_input "--flag"