path: root/src/flat_tree.rs

/// In the flat_tree structure, every "node" is just a line, there's
///  no link from a child to its parent or from a parent to its children.
use std::{
    cmp::{self, Ord, Ordering, PartialOrd},
    fs,
    mem,
    path::{Path, PathBuf},
};

#[cfg(unix)]
use {
    std::os::unix::fs::MetadataExt,
    umask::Mode,
};

#[cfg(windows)]
use is_executable::IsExecutable;

use crate::{
    errors,
    file_sizes::Size,
    task_sync::TaskLifetime,
    tree_build::TreeBuilder,
    tree_options::TreeOptions,
};

#[derive(Debug, Clone, PartialEq)]
pub enum LineType {
    File,
    Dir,
    SymLinkToDir(String),
    SymLinkToFile(String), // (to file or to symlink)
    Pruning,               // a "xxx unlisted" line
}

/// a line in the representation of the file hierarchy
#[derive(Debug, Clone)]
pub struct TreeLine {
    pub left_branchs: Box<[bool]>, // a depth-sized array telling whether a branch pass
    pub depth: u16,
    pub name: String,
    pub path: PathBuf,
    pub line_type: LineType,
    pub has_error: bool,
    pub nb_kept_children: usize,
    pub unlisted: usize, // number of not listed children (Dir) or brothers (Pruning)
    pub score: i32,      // 0 if there's no pattern
    pub size: Option<Size>, // None when not measured
    pub metadata: fs::Metadata,
}

#[derive(Debug, Clone)]
pub struct Tree {
    pub lines: Box<[TreeLine]>,
    pub selection: usize, // there's always a selection (starts with root, which is 0)
    pub options: TreeOptions,
    pub scroll: i32, // the number of lines at the top hidden because of scrolling
    pub nb_gitignored: u32, // number of times a gitignore pattern excluded a file
}

impl TreeLine {
    pub fn is_selectable(&self) -> bool {
        match &self.line_type {
            LineType::Pruning => false,
            _ => true,
        }
    }
    pub fn is_dir(&self) -> bool {
        match &self.line_type {
            LineType::Dir => true,
            LineType::SymLinkToDir(_) => true,
            _ => false,
        }
    }
    pub fn is_file(&self) -> bool {
        match &self.line_type {
            LineType::File => true,
            _ => false,
        }
    }
    #[cfg(unix)]
    pub fn mode(&self) -> Mode {
        Mode::from(self.metadata.mode())
    }
    pub fn is_exe(&self) -> bool {
        #[cfg(unix)]
        return self.mode().is_exe();

        #[cfg(windows)]
        return self.path.is_executable();
    }
    // build and return the absolute targeted path: either self.path or the
    //  solved canonicalized symlink
    // (the path may be invalid if the symlink is)
    pub fn target(&self) -> PathBuf {
        match &self.line_type {
            LineType::SymLinkToFile(target) | LineType::SymLinkToDir(target) => {
                let mut target_path = PathBuf::from(target);
                if target_path.is_relative() {
                    target_path = self.path.parent().unwrap().join(target_path);
                }
                if let Ok(canonic) = fs::canonicalize(&target_path) {
                    target_path = canonic;
                }
                target_path
            }
            _ => self.path.clone(),
        }
    }
}
impl PartialEq for TreeLine {
    fn eq(&self, other: &TreeLine) -> bool {
        self.path == other.path
    }
}

impl Eq for TreeLine {}

impl Ord for TreeLine {
    // paths are sorted in a complete ignore case way
    // (A<a<B<b)
    fn cmp(&self, other: &TreeLine) -> Ordering {
        let mut sci = self.path.components();
        let mut oci = other.path.components();
        loop {
            match sci.next() {
                Some(sc) => {
                    match oci.next() {
                        Some(oc) => {
                            let scs = sc.as_os_str().to_string_lossy();
                            let ocs = oc.as_os_str().to_string_lossy();
                            let lower_ordering = scs.to_lowercase().cmp(&ocs.to_lowercase());
                            if lower_ordering != Ordering::Equal {
                                return lower_ordering;
                            }
                            let ordering = scs.cmp(&ocs);
                            if ordering != Ordering::Equal {
                                return ordering;
                            }
                        }
                        None => {
                            return Ordering::Greater;
                        }
                    };
                }
                None => {
                    if oci.next().is_some() {
                        return Ordering::Less;
                    } else {
                        return Ordering::Equal;
                    }
                }
            };
        }
    }
}

impl PartialOrd for TreeLine {
    fn partial_cmp(&self, other: &TreeLine) -> Option<cmp::Ordering> {
        Some(self.cmp(other))
    }
}

impl Tree {
    pub fn refresh(&mut self, page_height: usize) -> Result<(), errors::TreeBuildError> {
        let builder =
            TreeBuilder::from(self.root().to_path_buf(), self.options.clone(), page_height)?;
        let mut tree = builder.build(&TaskLifetime::unlimited()).unwrap(); // should not fail
                                                                           // we save the old selection to try restore it
        let selected_path = self.selected_line().path.to_path_buf();
        mem::swap(&mut self.lines, &mut tree.lines);
        self.try_select_path(&selected_path);
        self.make_selection_visible(page_height as i32);
        Ok(())
    }

    /// do what must be done after line additions or removals:
    /// - sort the lines
    /// - compute left branchs
    pub fn after_lines_changed(&mut self) {
        // we sort the lines (this is mandatory to avoid crashes)
        self.lines[1..].sort();

        let mut best_index = 0; // index of the line with the best score
        for i in 1..self.lines.len() {
            if self.lines[i].score > self.lines[best_index].score {
                best_index = i;
            }
            for d in 0..self.lines[i].left_branchs.len() {
                self.lines[i].left_branchs[d] = false;
            }
        }
        // then we discover the branches (for the drawing)
        // and we mark the last children as pruning, if they have unlisted brothers
        let mut last_parent_index: usize = self.lines.len() + 1;
        for end_index in (1..self.lines.len()).rev() {
            let depth = (self.lines[end_index].depth - 1) as usize;
            let start_index = {
                let parent_index = {
                    let parent_path = &self.lines[end_index].path.parent();
                    match parent_path {
                        Some(parent_path) => {
                            let mut index = end_index;
                            loop {
                                index -= 1;
                                if self.lines[index].path == *parent_path {
                                    break;
                                }
                                if index == 0 {
                                    break;
                                }
                            }
                            index
                        }
                        None => end_index, // Should not happen
                    }
                };
                if parent_index != last_parent_index {
                    </