code cleanup

12 files changed, 105 insertions, 125 deletions

diff --git a/src/commands/cursor_move.rs b/src/commands/cursor_move.rs
index 60d4fd5..5757b47 100644
--- a/src/commands/cursor_move.rs
+++ b/src/commands/cursor_move.rs
@@ -55,12 +55,11 @@ pub fn cursor_move(context: &mut AppContext, new_index: usize) {
 }
 
 pub fn up(context: &mut AppContext, u: usize) -> JoshutoResult {
-    let movement = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => curr_list
-            .get_index()
-            .map(|idx| if idx > u { idx - u } else { 0 }),
-        None => None,
-    };
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|list| list.get_index().map(|idx| idx.saturating_sub(u)));
 
     if let Some(s) = movement {
         cursor_move(context, s);
@@ -69,10 +68,12 @@ pub fn up(context: &mut AppContext, u: usize) -> JoshutoResult {
 }
 
 pub fn down(context: &mut AppContext, u: usize) -> JoshutoResult {
-    let movement = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => curr_list.get_index().map(|idx| idx + u),
-        None => None,
-    };
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|list| list.get_index().map(|idx| idx.saturating_add(u)));
+
     if let Some(s) = movement {
         cursor_move(context, s);
     }
@@ -80,17 +81,18 @@ pub fn down(context: &mut AppContext, u: usize) -> JoshutoResult {
 }
 
 pub fn home(context: &mut AppContext) -> JoshutoResult {
-    let movement: Option<usize> = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => {
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|curr_list| {
             let len = curr_list.len();
             if len == 0 {
                 None
             } else {
                 Some(0)
             }
-        }
-        None => None,
-    };
+        });
 
     if let Some(s) = movement {
         cursor_move(context, s);
@@ -99,17 +101,18 @@ pub fn home(context: &mut AppContext) -> JoshutoResult {
 }
 
 pub fn end(context: &mut AppContext) -> JoshutoResult {
-    let movement: Option<usize> = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => {
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|curr_list| {
             let len = curr_list.len();
             if len == 0 {
                 None
             } else {
                 Some(len - 1)
             }
-        }
-        None => None,
-    };
+        });
 
     if let Some(s) = movement {
         cursor_move(context, s);
@@ -143,14 +146,11 @@ pub fn page_up(
     let page_size = get_page_size(context, backend).unwrap_or(10) as f64 * proportion;
     let page_size = page_size as usize;
 
-    let movement = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => {
-            curr_list
-                .get_index()
-                .map(|idx| if idx > page_size { idx - page_size } else { 0 })
-        }
-        None => None,
-    };
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|list| list.get_index().map(|idx| idx.saturating_sub(page_size)));
 
     if let Some(s) = movement {
         cursor_move(context, s);
@@ -166,19 +166,11 @@ pub fn page_down(
     let page_size = get_page_size(context, backend).unwrap_or(10) as f64 * proportion;
     let page_size = page_size as usize;
 
-    let movement = match context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        Some(curr_list) => {
-            let dir_len = curr_list.len();
-            curr_list.get_index().map(|idx| {
-                if idx + page_size > dir_len - 1 {
-                    dir_len - 1
-                } else {
-                    idx + page_size
-                }
-            })
-        }
-        None => None,
-    };
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|list| list.get_index().map(|idx| idx.saturating_add(page_size)));
 
     if let Some(s) = movement {
         cursor_move(context, s);
diff --git a/src/commands/file_ops.rs b/src/commands/file_ops.rs
index 708b642..e0976cf 100644
--- a/src/commands/file_ops.rs
+++ b/src/commands/file_ops.rs
@@ -68,9 +68,12 @@ pub fn copy_filename_without_extension(context: &mut AppContext) -> JoshutoResul
         .curr_tab_ref()
         .curr_list_ref()
         .and_then(|c| c.curr_entry_ref())
-        .map(|entry| match entry.file_name().rsplit_once('.') {
-            Some((name, _)) => name.to_string(),
-            _ => entry.file_name().to_string(),
+        .map(|entry| {
+            entry
+                .file_name()
+                .rsplit_once('.')
+                .map(|(name, _)| name.to_string())
+                .unwrap_or_else(|| entry.file_name().to_string())
         });
 
     if let Some(file_name) = entry_file_name {
@@ -101,10 +104,8 @@ pub fn copy_dirpath(context: &mut AppContext) -> JoshutoResult {
         .curr_list_ref()
         .map(|dirlist| dirlist.file_path());
 
-    if let Some(pathbuf) = opt_entry {
-        if let Some(dir) = pathbuf.to_str().map(String::from) {
-            copy_string_to_buffer(dir)?
-        }
+    if let Some(s) = opt_entry.and_then(|p| p.to_str().map(String::from)) {
+        copy_string_to_buffer(s)?
     };
     Ok(())
 }
diff --git a/src/commands/parent_cursor_move.rs b/src/commands/parent_cursor_move.rs
index febd391..b6c26fb 100644
--- a/src/commands/parent_cursor_move.rs
+++ b/src/commands/parent_cursor_move.rs
@@ -32,12 +32,11 @@ pub fn parent_cursor_move(context: &mut AppContext, new_index: usize) -> Joshuto
 }
 
 pub fn parent_up(context: &mut AppContext, u: usize) -> JoshutoResult {
-    let movement = match context.tab_context_ref().curr_tab_ref().parent_list_ref() {
-        Some(list) => list
-            .get_index()
-            .map(|idx| if idx > u { idx - u } else { 0 }),
-        None => None,
-    };
+    let movement = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .parent_list_ref()
+        .and_then(|list| list.get_index().map(|idx| idx.saturating_sub(u)));
 
     if let Some(s) = movement {
         parent_cursor_move(context, s)?;
diff --git a/src/commands/rename_file.rs b/src/commands/rename_file.rs
index 981cfcf..fa4a23d 100644
--- a/src/commands/rename_file.rs
+++ b/src/commands/rename_file.rs
@@ -101,13 +101,11 @@ pub fn rename_file_prepend(
     backend: &mut TuiBackend,
     keymap_t: &AppKeyMapping,
 ) -> JoshutoResult {
-    let mut file_name: Option<String> = None;
-
-    if let Some(curr_list) = context.tab_context_ref().curr_tab_ref().curr_list_ref() {
-        file_name = curr_list
-            .curr_entry_ref()
-            .map(|s| s.file_name().to_string());
-    }
+    let file_name = context
+        .tab_context_ref()
+        .curr_tab_ref()
+        .curr_list_ref()
+        .and_then(|list| list.curr_entry_ref().map(|s| s.file_name().to_string()));
 
     if let Some(file_name) = file_name {
         _rename_file_prepend(context, backend, keymap_t, file_name)?;
diff --git a/src/commands/sub_process.rs b/src/commands/sub_process.rs
index 08629ab..db699dd 100644
--- a/src/commands/sub_process.rs
+++ b/src/commands/sub_process.rs
@@ -16,10 +16,12 @@ fn execute_sub_process(
             "%s" => {
                 if let Some(curr_list) = context.tab_context_ref().curr_tab_ref().curr_list_ref() {
                     let mut i = 0;
-                    for entry in curr_list.iter_selected().map(|e| e.file_name()) {
-                        command.arg(entry);
-                        i += 1;
-                    }
+                    curr_list.iter_selected()
+                        .map(|e| e.file_name())
+                        .for_each(|file_name| {
+                            command.arg(file_name);
+                            i += 1;
+                        });
                     if i == 0 {
                         if let Some(entry) = curr_list.curr_entry_ref() {
                             command.arg(entry.file_name());
diff --git a/src/context/worker_context.rs b/src/context/worker_context.rs
index d8aea55..fdd76fa 100644
--- a/src/context/worker_context.rs
+++ b/src/context/worker_context.rs
@@ -7,6 +7,7 @@ use crate::event::AppEvent;
 use crate::io::{IoWorkerObserver, IoWorkerProgress, IoWorkerThread};
 
 pub struct WorkerContext {
+    // forks of applications
     child_pool: HashMap<u32, thread::JoinHandle<()>>,
     // to send info
     event_tx: mpsc::Sender<AppEvent>,
diff --git a/src/event/app_event.rs b/src/event/app_event.rs
index aa39f00..fd232f6 100644
--- a/src/event/app_event.rs
+++ b/src/event/app_event.rs
@@ -16,18 +16,24 @@ use crate::preview::preview_file::FilePreview;
 
 #[derive(Debug)]
 pub enum AppEvent {
+    // User input events
     Termion(Event),
 
+    // background IO worker events
     IoWorkerCreate,
     IoWorkerProgress(IoWorkerProgress),
     IoWorkerResult(io::Result<IoWorkerProgress>),
 
+    // forked process events
     ChildProcessComplete(u32),
 
+    // preview thread events
     PreviewDir(io::Result<JoshutoDirList>),
     PreviewFile(path::PathBuf, io::Result<FilePreview>),
 
+    // terminal size change events
     Signal(i32),
+    // filesystem change events
     Filesystem(notify::Event),
 }
 
@@ -44,13 +50,30 @@ pub struct Events {
 
 impl Events {
     pub fn new() -> Self {
-        Events::with_config()
+        Self::default()
     }
 
-    pub fn with_config() -> Self {
+    // We need a next() and a flush() so we don't continuously consume
+    // input from the console. Sometimes, other applications need to
+    // read terminal inputs while joshuto is in the background
+    pub fn next(&self) -> Result<AppEvent, mpsc::RecvError> {
+        let event = self.event_rx.recv()?;
+        Ok(event)
+    }
+
+    pub fn flush(&self) {
+        let _ = self.input_tx.send(());
+    }
+}
+
+impl std::default::Default for Events {
+    fn default() -> Self {
         let (input_tx, input_rx) = mpsc::sync_channel(1);
         let (event_tx, event_rx) = mpsc::channel();
 
+        // edge case that starts off the input thread
+        let _ = input_tx.send(());
+
         // signal thread
         let event_tx2 = event_tx.clone();
         let _ = thread::spawn(move || {
@@ -69,25 +92,10 @@ impl Events {
         let _ = thread::spawn(move || {
             let stdin = io::stdin();
             let mut events = stdin.events();
-            match events.next() {
-                Some(event) => match event {
-                    Ok(event) => {
-                        if let Err(e) = event_tx2.send(AppEvent::Termion(event)) {
-                            eprintln!("Input thread send err: {:#?}", e);
-                            return;
-                        }
-                    }
-                    Err(_) => return,
-                },
-                None => return,
-            }
 
             while input_rx.recv().is_ok() {
                 if let Some(Ok(event)) = events.next() {
-                    if let Err(e) = event_tx2.send(AppEvent::Termion(event)) {
-                        eprintln!("Input thread send err: {:#?}", e);
-                        return;
-                    }
+                    let _ = event_tx2.send(AppEvent::Termion(event));
                 }
             }
         });
@@ -98,16 +106,4 @@ impl Events {
             input_tx,
         }
     }
-
-    // We need a next() and a flush() so we don't continuously consume
-    // input from the console. Sometimes, other applications need to
-    // read terminal inputs while joshuto is in the background
-    pub fn next(&self) -> Result<AppEvent, mpsc::RecvError> {
-        let event = self.event_rx.recv()?;
-        Ok(event)
-    }
-
-    pub fn flush(&self) {
-        let _ = self.input_tx.send(());
-    }
 }
diff --git a/src/fs/dirlist.rs b/src/fs/dirlist.rs
index 719ca71..33ee7c9 100644
--- a/src/fs/dirlist.rs
+++ b/src/fs/dirlist.rs
@@ -1,5 +1,5 @@
-use std::path;
 use std::slice::{Iter, IterMut};
+use std::{io, path};
 
 use crate::config::option::DisplayOption;
 use crate::context::UiContext;
@@ -36,15 +36,14 @@ impl JoshutoDirList {
         }
     }
 
-    pub fn from_path(path: path::PathBuf, options: &DisplayOption) -> std::io::Result<Self> {
+    pub fn from_path(path: path::PathBuf, options: &DisplayOption) -> io::Result<Self> {
         let filter_func = options.filter_func();
-        let mut contents = read_directory(path.as_path(), filter_func, options)?;
-
         let sort_options = options.sort_options_ref();
+
+        let mut contents = read_directory(path.as_path(), filter_func, options)?;
         contents.sort_by(|f1, f2| sort_options.compare(f1, f2));
 
         let index = if contents.is_empty() { None } else { Some(0) };
-
         let metadata = JoshutoMetadata::from(&path)?;
 
         Ok(Self {
@@ -125,13 +124,10 @@ impl JoshutoDirList {
 
     pub fn modified(&self) -> bool {
         let metadata = std::fs::symlink_metadata(self.file_path());
-        match metadata {
-            Ok(m) => match m.modified() {
-                Ok(s) => s > self.metadata.modified(),
-                _ => false,
-            },
-            _ => false,
-        }
+        metadata
+            .and_then(|m| m.modified())
+            .map(|m| m > self.metadata.modified())
+            .unwrap_or(false)
     }
 
     pub fn depreciate(&mut self) {
@@ -142,8 +138,8 @@ impl JoshutoDirList {
         self._need_update || self.modified()
     }
 
-    pub fn file_path(&self) -> &path::PathBuf {
-        &self.path
+    pub fn file_path(&self) -> &path::Path {
+        self.path.as_path()
     }
 
     pub fn any_selected(&self) -> bool {
diff --git a/src/history.rs b/src/history.rs
index 9e0c558..80afa37 100644
--- a/src/history.rs
+++ b/src/history.rs
@@ -134,7 +134,7 @@ pub fn create_dirlist_with_history(
     contents.sort_by(|f1, f2| sort_options.compare(f1, f2));
 
     let contents_len = contents.len();
-    let index: Option<usize> = if contents_len == 0 {
+    let index = if contents_len == 0 {
         None
     } else {
         match history.get(path) {
diff --git a/src/ui/views/tui_folder_view.rs b/src/ui/views/tui_folder_view.rs
index 1be9367..966a48e 100644
--- a/src/ui/views/tui_folder_view.rs
+++ b/src/ui/views/tui_folder_view.rs
@@ -172,11 +172,7 @@ impl<'a> Widget for TuiFolderView<'a> {
 
         // render tabs
         if self.context.tab_context_ref().len() > 1 {
-            let topbar_width = if area.width > TAB_VIEW_WIDTH {
-                area.width - TAB_VIEW_WIDTH
-            } else {
-                0
-            };
+            let topbar_width = area.width.saturating_sub(TAB_VIEW_WIDTH);
 
             let rect = Rect {
                 x: topbar_width,
diff --git a/src/ui/views/tui_textfield.rs b/src/ui/views/tui_textfield.rs
index b2372d4..997e664 100644
--- a/src/ui/views/tui_textfield.rs
+++ b/src/ui/views/tui_textfield.rs
@@ -172,11 +172,7 @@ impl<'a> TuiTextField<'a> {
                             Key::Home => line_buffer.move_home(),
                             Key::End => line_buffer.move_end(),
                             Key::Up => {
-                                curr_history_index = if curr_history_index > 0 {
-                                    curr_history_index - 1
-                                } else {
-                                    0
-                                };
+                                curr_history_index = curr_history_index.saturating_sub(1);
                                 line_buffer.move_home();
                                 line_buffer.kill_line();
                                 if let Some(s) = context
diff --git a/src/util/style.rs b/src/util/style.rs
index 4670792..4312425 100644
--- a/src/util/style.rs
+++ b/src/util/style.rs
@@ -48,14 +48,17 @@ fn file_style(entry: &JoshutoDirEntry) -> Style {
             .bg(THEME_T.executable.bg)
             .add_modifier(THEME_T.executable.modifier)
     } else {
-        match entry
+        entry
             .file_path()
             .extension()
             .and_then(|s| s.to_str())
             .and_then(|s| THEME_T.ext.get(s))
-        {
-            Some(t) => Style::default().fg(t.fg).bg(t.bg).add_modifier(t.modifier),
-            None => regular_style,
-        }
+            .map(|theme| {
+                Style::default()
+                    .fg(theme.fg)
+                    .bg(theme.bg)
+                    .add_modifier(theme.modifier)
+            })
+            .unwrap_or(regular_style)
     }
 }