sea-shell 0.0.12

A portable Bash-like shell written in Rust
Documentation
#![cfg_attr(not(feature = "std"), no_std)]

pub(crate) mod re_exports {
  #[cfg(not(feature = "std"))]
  pub extern crate alloc;
  #[cfg(feature = "std")]
  pub use std as alloc;

  pub use crate::arg_parser::Arg;
  pub use crate::logger::create_logger_from_logger;
  pub use alloc::{
    boxed::Box,
    collections::BTreeMap,
    format,
    string::{String, ToString},
    sync::Arc,
    vec::Vec,
  };
  pub use core::{
    fmt::{self, Display, Formatter, Result as FmtResult},
    future::Future,
    pin::Pin,
  };
  pub use itertools::Itertools;
}

use core::future::Future as Future_;
use re_exports::*;

mod state;

pub use state::State;

pub mod arg_parser;
pub mod commands;
pub mod logger;

pub(crate) mod macro_helpers;

pub const VERSION: &str = env!("CARGO_PKG_VERSION");
pub const DESCRIPTION: &str = env!("CARGO_PKG_DESCRIPTION");

#[derive(Clone)]
pub struct SeaShell<'a> {
  pub state: State,
  #[allow(clippy::type_complexity)]
  pub exit_handler: Arc<Box<dyn Fn(i32, Self) -> Option<Self> + 'a>>,
  pub logger: Arc<Box<dyn logger::Logger + 'a>>,
}

impl<'a> SeaShell<'a> {
  pub fn new(
    exit_handler: impl Fn(i32, Self) -> Option<Self> + 'a,
    logger_: impl logger::Logger + 'a,
    unicode_supported: bool,
  ) -> Self {
    create_logger_from_logger!(logger_, true);

    log!(info, "Welcome to Sea Shell version: {}", VERSION);
    log!(info, DESCRIPTION);
    log!(info, "Type 'help' for a list of commands");
    log!();

    Self {
      exit_handler: Arc::new(Box::new(exit_handler)),
      state: State::new(commands::BUILT_IN_COMMANDS, unicode_supported),
      logger: Arc::new(Box::new(logger_)),
    }
  }

  pub async fn handle_command(&mut self, input: impl AsRef<str>) {
    let input = input.as_ref().trim();

    if input.is_empty() {
      return;
    }

    let mut input_ = input.split_whitespace().filter_map(|input| {
      let trimmed = input.trim();

      if trimmed.is_empty() {
        None
      } else {
        Some(trimmed.into())
      }
    });

    let command = input_.next().unwrap();

    let args = input_.collect::<Vec<_>>();

    self.state.history.push(input.into());

    create_logger_from_logger!(self.logger, true);
    let code = match self.get_command(&command) {
      Some(command_) => {
        log!(debug, "executing: {}...", command);

        let out = (command_.handler)(self.clone(), args).await;

        if let Some(self_) = out.0 {
          *self = self_;
        }

        out.1
      }
      None => {
        log!(error, "command not found: {}", command);

        1
      }
    };

    self
      .state
      .set_environment_variable("exit", code.to_string());
  }

  pub fn get_command(&self, command: impl AsRef<str>) -> Option<&Command> {
    let command = command.as_ref();

    self.state.commands.iter().find(|c| c.name == command)
  }
}

#[derive(Clone)]
pub struct Command {
  pub name: &'static str,
  pub description: &'static str,
  pub args: &'static [Arg<'static>],
  #[allow(clippy::type_complexity)]
  pub handler: for<'a> fn(SeaShell<'a>, Vec<String>) -> Future<'a, (Option<SeaShell<'a>>, i32)>,
}

impl Display for Command {
  fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
    let mut help_text = String::new();

    help_text.push_str(self.name);

    if !self.args.is_empty() {
      help_text.push(' ');

      for arg in self.args {
        help_text.push_str(&format!("{}", arg));
      }
    }

    help_text.push_str(": ");
    help_text.push_str(self.description);

    write!(f, "{}", help_text)
  }
}

pub(crate) type Future<'a, T> = Pin<Box<dyn Future_<Output = T> + 'a>>;