basalt_cli.rs

use clap::{ Args, Parser, Subcommand };

use std::fmt::{ self };
use std::io::{ self };
use std::path::{ PathBuf };
use std::process::{ ExitCode };

// -------------------------------------------------------------------------------------------------
// Command line arguments
// -------------------------------------------------------------------------------------------------

#[derive(Parser)]
#[command(author, version, about, propagate_version = true)]
struct Arguments {
	#[command(subcommand)]
	command: Command,
}

#[derive(Subcommand)]
enum Command {
	/// Generates a new database file
	CreateDatabase(CreateDatabaseArguments),
}

#[derive(Args)]
struct CreateDatabaseArguments {
	path: PathBuf,
}

impl Command {
	fn run(&self) -> Result<()> {
		match *self {
			Command::CreateDatabase(ref arguments) => {
				let _ = basalt::create_database(&arguments.path)?;
				Ok(())
			}
		}
	}
}

// -------------------------------------------------------------------------------------------------
// Error handling
// -------------------------------------------------------------------------------------------------

type Result<T> = ::std::result::Result<T, Error>;

#[derive(Debug)]
enum Error {
	FromBasalt(basalt::Error),
	FromStdIo(io::Error),
}

impl fmt::Display for Error {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		use Error::*;

		match *self {
			FromBasalt(ref e) => write!(f, "Basalt error: {}", e),
			FromStdIo(ref e) => write!(f, "IO error: {}", e),
		}
	}
}

impl From<io::Error> for Error {
	fn from(e: io::Error) -> Error {
		Error::FromStdIo(e)
	}
}

impl From<basalt::Error> for Error {
	fn from(e: basalt::Error) -> Error {
		Error::FromBasalt(e)
	}
}

// -------------------------------------------------------------------------------------------------
// Entry point
// -------------------------------------------------------------------------------------------------

fn main() -> ExitCode {
	let arguments = Arguments::parse();

	match arguments.command.run() {
		Ok(_) => ExitCode::SUCCESS,
		Err(e) => {
			eprintln!("{}", e);
			ExitCode::FAILURE
		}
	}
}