show.py

from typing import Dict, TypedDict

import typer


class CommandInfo(TypedDict):
    description: str
    usage: str
    example: str
    notes: str


COMMANDS: Dict[str, CommandInfo] = {
    "ls": {
        "description": (
            "List information about the files in the current directory (the default). "
            "Options can be used to modify the output format, sort order, and more."
        ),
        "usage": "ls [OPTION]... [FILE]...",
        "example": "ls -la /var/log",
        "notes": (
            "- `-l` : use a long listing format\n"
            "- `-a` : show hidden files (starting with `.`)\n"
            "- `-h` : with -l, print sizes in human-readable format (e.g., 1K, 234M)"
        ),
    },
    "grep": {
        "description": (
            "Search input files for lines containing a match to the given PATTERN. "
            "Often used for filtering log files or searching through code."
        ),
        "usage": "grep [OPTION]... PATTERN [FILE]...",
        "example": 'grep -R "TODO" .',
        "notes": (
            "- `-i` : ignore case distinctions\n"
            "- `-R` : recursively search subdirectories\n"
            "- `-n` : show line numbers of matches"
        ),
    },
    "cat": {
        "description": (
            "Concatenate files and print on the standard output. "
            "Often used to quickly view file contents."
        ),
        "usage": "cat [OPTION]... [FILE]...",
        "example": "cat /etc/passwd",
        "notes": (
            "- `-n` : number all output lines\n"
            "- `-b` : number non-blank lines\n"
            "- Use with pipes: `cat file.txt | grep pattern`"
        ),
    },
    "mkdir": {
        "description": (
            "Create directories if they do not already exist. "
            "By default, it creates a single directory."
        ),
        "usage": "mkdir [OPTION]... DIRECTORY...",
        "example": "mkdir -p projects/python/app",
        "notes": (
            "- `-p` : create parent directories as needed\n"
            "- `-v` : print a message for each created directory"
        ),
    },
}


def show(
    command: str = typer.Argument(..., help="Linux command to show details for")
) -> None:
    """
    Display description, usage, examples, and notes for a given Linux command.
    """

    key = command.strip()
    info = COMMANDS.get(key)

    if not info:
        typer.secho(
            f"✖ Unknown command '{command}'. Try one of: {', '.join(sorted(COMMANDS))}",
            err=True,
            fg=typer.colors.RED,
        )
        raise typer.Exit(code=1)

    typer.secho(f"\nCommand: {key}\n", fg=typer.colors.CYAN, bold=True)

    typer.secho("Description:", fg=typer.colors.MAGENTA, bold=True)
    typer.echo(f"  {info['description']}\n")

    typer.secho("Usage:", fg=typer.colors.MAGENTA, bold=True)
    typer.echo(f"  {info['usage']}\n")

    typer.secho("Example:", fg=typer.colors.MAGENTA, bold=True)
    typer.echo(f"  {info['example']}\n")

    typer.secho("Notes:", fg=typer.colors.MAGENTA, bold=True)
    typer.echo(f"{info['notes']}\n")