trash-utils 0.2.0

mod error;
mod utils;

use std::cmp::Ordering;
use std::fmt;
use std::fs;
use std::io;
use std::path::{Path, PathBuf};
use std::str::FromStr;

use chrono::prelude::{DateTime, Local, TimeZone};
use itertools::Itertools; // TODO: why?
use nom::bytes::complete::{tag, take_until};
use nom::combinator::map_res;
use nom::error::VerboseError;
use nom::IResult;
use path_clean::PathClean;
use platform_dirs::{AppDirs, AppUI};
use snafu::{ensure, OptionExt, ResultExt};

pub use error::*;
use utils::{move_file, AbsolutePath};

pub struct Trash {
	home_trash: PathBuf,
}

impl Trash {
	// TODO: errors
	pub fn new() -> io::Result<Trash> {
		let home_trash = AppDirs::new::<PathBuf>(None, AppUI::CommandLine)
			.unwrap()
			.data_dir
			.join("Trash");
		fs::create_dir_all(home_trash.join("files"))?;
		fs::create_dir_all(home_trash.join("info"))?;
		Ok(Trash { home_trash })
	}

	pub fn get_trashed_files(&self) -> Result<Vec<Result<TrashEntry>>> {
		let results = self
			.home_trash
			.join("info")
			.read_dir()
			.context(ReadTrashInfoDir)?
			.map(|dir_entry| {
				let trash_info_path = dir_entry.context(ReadTrashInfoDir)?.path();
				let trashed_path =
					self.home_trash
						.join("files")
						.join(trash_info_path.file_stem().context({
							InvalidTrashInfoPath {
								path: &trash_info_path,
							}
						})?);
				let trash_info = fs::read_to_string(&trash_info_path)
					.context(ReadTrashInfo {
						path: &trash_info_path,
					})?
					.parse::<TrashInfo>()
					.context(ParseTrashInfo {
						path: &trash_info_path,
					})?;
				Ok(TrashEntry {
					trashed_path,
					trash_info,
				})
			})
			// TODO: what is this?
			.sorted_by(|result1, result2| match result1 {
				Ok(x) => match result2 {
					Ok(y) => Ord::cmp(&x.trash_info.deletion_date, &y.trash_info.deletion_date),
					Err(_) => Ordering::Less,
				},
				Err(_) => Ordering::Less,
			})
			.collect();

		Ok(results)
	}

	pub fn trash_file<P>(&self, path: P) -> Result<PathBuf>
	where
		P: AsRef<Path>,
	{
		let path = path.as_ref();
		let path = path.absolute_path().map_err(|_| Error::InvalidPath {
			path: path.to_path_buf(),
		})?;
		ensure!(path.exists(), InvalidPath { path });

		// check if given file contains the trash-can
		ensure!(
			!self.home_trash.starts_with(&path),
			TrashingTrashCan { path }
		);

		let trashed_path = move_file(
			&path,
			&self
				.home_trash
				.join("files")
				.join(path.file_name().expect("path is clean")),
		)
		.context(MoveFile { path: &path })?;

		let trash_info_path = get_trash_info_path(&self.home_trash, &trashed_path);
		let trash_info = TrashInfo {
			original_path: path.to_path_buf(),
			deletion_date: Local::now(),
		};
		fs::write(trash_info_path, format!("{}\n", trash_info)).context(WriteTrashInfo { path })?;

		Ok(trashed_path)
	}

	pub fn restore_trashed_file<P>(&self, path: P) -> Result<PathBuf>
	where
		P: AsRef<Path>,
	{
		let path = path.as_ref();
		let path = path.absolute_path().map_err(|_| Error::InvalidPath {
			path: path.to_path_buf(),
		})?;
		ensure!(path.exists(), InvalidPath { path });

		let trash_info_path = get_trash_info_path(&self.home_trash, &path);
		let original_path = fs::read_to_string(&trash_info_path)
			.context(ReadTrashInfo {
				path: &trash_info_path,
			})?
			.parse::<TrashInfo>()
			.context(ParseTrashInfo { path: &path })?
			.original_path;
		let restored_path = move_file(&path, &original_path).context(MoveFile { path: &path })?;
		fs::remove_file(trash_info_path).context(RemoveFile { path })?;

		Ok(restored_path)
	}

	pub fn erase_file<P>(&self, path: P) -> Result<()>
	where
		P: AsRef<Path>,
	{
		let path = path.as_ref();
		let path = path.absolute_path().map_err(|_| Error::InvalidPath {
			path: path.to_path_buf(),
		})?;
		ensure!(path.exists(), InvalidPath { path });

		if self.is_file_trashed(&path).expect("file exists") {
			fs::remove_file(get_trash_info_path(&self.home_trash, &path))
				.context(RemoveFile { path: &path })?;
		}
		if path.is_dir() {
			fs::remove_dir_all(&path).context(RemoveFile { path: &path })?;
		} else {
			fs::remove_file(&path).context(RemoveFile { path: &path })?;
		}

		Ok(())
	}

	pub fn is_file_trashed<P>(&self, path: P) -> Result<bool>
	where
		P: AsRef<Path>,
	{
		let path = path.as_ref();
		let path = path.absolute_path().map_err(|_| Error::InvalidPath {
			path: path.to_path_buf(),
		})?;
		ensure!(path.exists(), InvalidPath { path });

		Ok(path.starts_with(&self.home_trash.join("files")))
	}
}

fn get_trash_info_path(trash_path: &Path, file: &Path) -> PathBuf {
	trash_path.join("info").join(format!(
		"{}.trashinfo",
		file.file_name().expect("path is clean").to_string_lossy()
	))
}

#[derive(Debug, PartialEq, Eq)]
pub struct TrashEntry {
	pub trashed_path: PathBuf,
	pub trash_info: TrashInfo,
}

#[derive(Debug, PartialEq, Eq)]
pub struct TrashInfo {
	pub original_path: PathBuf,
	pub deletion_date: DateTime<Local>,
}

fn parse_trash_info<'a>(input: &'a str) -> IResult<&'a str, TrashInfo, VerboseError<&'a str>> {
	let (input, _) = tag("[Trash Info]\n")(input)?;

	let (input, _) = tag("Path=")(input)?;
	let (input, original_path) = map_res(take_until("\n"), |input| {
		let path = PathBuf::from(input);
		if path.is_relative() || path.parent().is_none() || path != path.clean() {
			Err(io::Error::new(io::ErrorKind::InvalidData, "invalid path"))
		} else {
			Ok(path)
		}
	})(input)?;
	let (input, _) = tag("\n")(input)?;

	let (input, _) = tag("DeletionDate=")(input)?;
	let (input, deletion_date) = map_res(take_until("\n"), |input| {
		Local.datetime_from_str(input, "%Y-%m-%dT%H:%M:%S")
	})(input)?;

	Ok((
		input,
		TrashInfo {
			original_path,
			deletion_date,
		},
	))
}

// TODO
impl FromStr for TrashInfo {
	type Err = io::Error;

	fn from_str(s: &str) -> io::Result<Self> {
		parse_trash_info(s).map(|x| x.1).map_err(|_| {
			// TODO figure out how to convert nom::error to failure::error while preserving its error message.
			// Was having issues since failure::error requires a static lifetime and nom::error contains a &str.
			io::Error::new(io::ErrorKind::InvalidData, "failed to parse TrashInfo").into()
		})
	}
}

impl fmt::Display for TrashInfo {
	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
		write!(
			f,
			"[Trash Info]\nPath={}\nDeletionDate={}",
			self.original_path.display(),
			self.deletion_date.format("%Y-%m-%dT%H:%M:%S"),
		)
	}
}

#[cfg(test)]
mod tests {
	use super::*;

	#[test]
	fn test_get_trashed_files() {
		use std::fs::File;

		let trash = Trash {
			home_trash: PathBuf::from("test2"),
		};
		fs::create_dir_all(&trash.home_trash.join("files"));
		fs::create_dir_all(&trash.home_trash.join("info"));
		let trash_info = TrashInfo {
			original_path: PathBuf::from("/asdf/123"),
			deletion_date: Local.ymd(2014, 7, 8).and_hms(9, 10, 11),
		};

		fs::remove_dir_all(trash.home_trash).unwrap();
	}

	#[test]
	fn test_trash_file() {}

	#[test]
	fn test_restore_trashed_file() {}

	#[test]
	fn test_erase_file() {
		use std::fs::File;

		let trash = Trash {
			home_trash: PathBuf::from("test"),
		};
		let files_dir = trash.home_trash.join("files");
		let info_dir = trash.home_trash.join("info");
		let in_trash = files_dir.join("in_trash");
		let in_trash_trash_info = info_dir.join("in_trash.trashinfo");

		fs::create_dir_all(&files_dir);
		fs::create_dir_all(&info_dir);

		assert!(&files_dir.exists());
		assert!(&info_dir.exists());

		File::create(&in_trash);
		File::create(&in_trash_trash_info);

		assert!((&in_trash).exists());
		assert!((&in_trash_trash_info).exists());

		trash.erase_file(&in_trash);

		assert!(!(&in_trash).exists());
		assert!(!(&in_trash_trash_info).exists());

		let out_trash = trash.home_trash.join("asdf");
		File::create(&out_trash);
		assert!(&out_trash.exists());
		trash.erase_file(&out_trash);
		assert!(!&out_trash.exists());

		fs::remove_dir_all(trash.home_trash).unwrap();
	}

	#[test]
	fn test_is_file_trashed() {
		let trash = Trash {
			home_trash: PathBuf::from("/test/trash"),
		};
		let file1 = PathBuf::from("/test/trash/files/foo");
		let file2 = PathBuf::from("/test/trash/info/foo");
		assert!(trash.is_file_trashed(file1).unwrap());
		assert!(!trash.is_file_trashed(file2).unwrap());
	}

	#[test]
	fn test_trash_info_parsing() {
		let trash_info = TrashInfo {
			original_path: PathBuf::from("/asdf/123"),
			deletion_date: Local.ymd(2014, 7, 8).and_hms(9, 10, 11),
		};
		let trash_info_to_str = "[Trash Info]\nPath=/asdf/123\nDeletionDate=2014-07-08T09:10:11";
		assert_eq!(trash_info, trash_info_to_str.parse::<TrashInfo>().unwrap());
	}

	#[test]
	fn test_trash_info_display() {
		let trash_info = TrashInfo {
			original_path: PathBuf::from("/asdf/123"),
			deletion_date: Local.ymd(2014, 7, 8).and_hms(9, 10, 11),
		};
		let trash_info_to_str = "[Trash Info]\nPath=/asdf/123\nDeletionDate=2014-07-08T09:10:11";
		assert_eq!(trash_info.to_string(), trash_info_to_str);
	}
}