punktf-lib 2.0.2

//! Provides definitions for the `punktf` source directory.
//!
//! The source directory is the central repository used to store
//! [`Profile`s](`crate::profile::Profile`) and [`Dotfile`s](`crate::profile::dotfile::Dotfile`).
//! `punktf` will only read data from these directories but never write to them.
//!
//! The current structure looks something like this:
//!
//! ```text
//! root/
//! + profiles/
//!   ...
//! + dotfiles/
//!   ...
//! ```

use color_eyre::eyre::Context as _;
use std::path::{Path, PathBuf};

/// This struct represents the source directory used by `punktf`. The source
/// directory is the central repository used to store
/// [`Profile`s](`crate::profile::Profile`) and [`Dotfile`s](`crate::profile::dotfile::Dotfile`).
/// `punktf` will only read data from these directories but never write to them.
///
/// The current structure looks something like this:
///
/// ```text
/// root/
/// + profiles/
///   ...
/// + dotfiles/
///   ...
/// ```
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct PunktfSource {
	/// The absolute root source path.
	pub root: PathBuf,

	/// The absolute path to the `profiles` directory.
	pub profiles: PathBuf,

	/// The absolute path to the `dotfiles` directory.
	pub dotfiles: PathBuf,
}

impl PunktfSource {
	/// Creates a instance from a `root` directory. During instantiation it
	/// checks if the `root` exists and is a directory. These checks will also
	/// be run for the `root/profiles` and `root/dotfiles` subdirectories. All
	/// the above mentioned paths will also be resolved by calling
	/// [`std::path::Path::canonicalize`].
	///
	/// # Errors
	///
	/// If any of the checks fail an error will be returned.
	pub fn from_root(root: PathBuf) -> color_eyre::Result<Self> {
		/// Tries to create a directory if it does not exist.
		/// Bubbles up any error encountered and add some context to it.
		macro_rules! try_exists {
			( $var:ident ) => {
				// TODO: Replace once `try_exists` becomes stable
				if $var.exists() {
					// Should check if read/write is possible
				} else {
					let _ = std::fs::create_dir(&$var).wrap_err_with(|| {
						format!(
							"{} directory does not exist and could not be created (path: {})",
							stringify!($var),
							$var.display()
						)
					})?;
				}
			};
		}

		/// Tries to canonicalize/resolve a path.
		/// Bubbles up any error encountered and add some context to it.
		macro_rules! try_canonicalize {
			($var:ident) => {
				$var.canonicalize().wrap_err_with(|| {
					format!(
						"Failed to resolve punktf's {} directory (path: {})",
						stringify!($var),
						$var.display()
					)
				})?
			};
		}

		// Renames the `root` variable for better error messages
		let source = root;
		try_exists!(source);
		let source = try_canonicalize!(source);

		let profiles = source.join("profiles");
		try_exists!(profiles);
		let profiles = try_canonicalize!(profiles);

		let dotfiles = source.join("dotfiles");
		try_exists!(dotfiles);
		let dotfiles = try_canonicalize!(dotfiles);

		Ok(Self {
			root: source,
			profiles,
			dotfiles,
		})
	}

	/// Returns the absolute path for the `root` directory.
	pub fn root(&self) -> &Path {
		&self.root
	}

	/// Returns the absolute path to the `root/profiles` directory.
	pub fn profiles(&self) -> &Path {
		&self.profiles
	}

	/// Returns the absolute path to the `root/dotfiles` directory.
	pub fn dotfiles(&self) -> &Path {
		&self.dotfiles
	}
}