Refactored some UI utility and command prompt into separate modules.

src/keyboard.rs

@@ -20,7 +20,7 @@ pub fn handle(greeter: &mut Greeter, events: &Events) -> Result<(), Box<dyn Erro
       Key::Right => greeter.cursor_offset += 1,
 
       Key::F(2) => {
-        greeter.new_command = greeter.command.clone().unwrap_or_else(String::new);
+        greeter.new_command = greeter.command.clone().unwrap_or_default();
         greeter.previous_mode = greeter.mode;
         greeter.mode = Mode::Command;
       }

src/ui/command.rs

@@ -0,0 +1,51 @@
+use std::{error::Error, io};
+
+use termion::raw::RawTerminal;
+use tui::{
+  backend::TermionBackend,
+  layout::{Constraint, Direction, Layout, Rect},
+  widgets::{Block, BorderType, Borders, Paragraph, Text},
+  Frame,
+};
+
+use super::prompt_value;
+use crate::{ui::util::*, Greeter};
+
+const CHANGE_COMMAND: &str = " Change session command ";
+const COMMAND: &str = "New command:";
+
+pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::Stdout>>>) -> Result<(u16, u16), Box<dyn Error>> {
+  let size = f.size();
+
+  let width = greeter.width();
+  let height = get_height(&greeter);
+  let container_padding = greeter.container_padding();
+  let x = (size.width - width) / 2;
+  let y = (size.height - height) / 2;
+
+  let container = Rect::new(x, y, width, height);
+  let frame = Rect::new(x + container_padding, y + container_padding, width - container_padding, height - container_padding);
+
+  let block = Block::default().title(CHANGE_COMMAND).borders(Borders::ALL).border_type(BorderType::Plain);
+
+  f.render_widget(block, container);
+
+  let constraints = [
+    Constraint::Length(1), // Username
+  ];
+
+  let chunks = Layout::default().direction(Direction::Vertical).constraints(constraints.as_ref()).split(frame);
+  let cursor = chunks[0];
+
+  let command_label_text = [prompt_value(COMMAND)];
+  let command_label = Paragraph::new(command_label_text.iter());
+  let command_value_text = [Text::raw(&greeter.new_command)];
+  let command_value = Paragraph::new(command_value_text.iter());
+
+  f.render_widget(command_label, chunks[0]);
+  f.render_widget(command_value, Rect::new(1 + chunks[0].x + COMMAND.len() as u16, chunks[0].y, get_input_width(greeter, COMMAND), 1));
+
+  let offset = get_cursor_offset(greeter, greeter.new_command.len());
+
+  Ok((2 + cursor.x + COMMAND.len() as u16 + offset as u16, cursor.y + 1))
+}

src/ui/mod.rs

@@ -1,5 +1,7 @@
+mod command;
 mod prompt;
 mod sessions;
+mod util;
 
 use std::{
   error::Error,
@@ -81,6 +83,7 @@ pub fn draw(terminal: &mut Terminal<TermionBackend<RawTerminal<io::Stdout>>>, gr
     }
 
     cursor = match greeter.mode {
+      Mode::Command => self::command::draw(greeter, &mut f).ok(),
       Mode::Sessions => self::sessions::draw(greeter, &mut f).ok(),
       _ => self::prompt::draw(greeter, &mut f).ok(),
     }

src/ui/prompt.rs

@@ -8,7 +8,7 @@ use tui::{
   Frame,
 };
 
-use super::prompt_value;
+use super::{prompt_value, util::*};
 use crate::{info::get_hostname, Greeter, Mode};
 
 const GREETING_INDEX: usize = 0;
@@ -18,7 +18,6 @@ const MESSAGE_INDEX: usize = 3;
 
 const TITLE: &str = "Authenticate into";
 const USERNAME: &str = "Username:";
-const COMMAND: &str = "New command:";
 const WORKING: &str = "Please wait...";
 
 pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::Stdout>>>) -> Result<(u16, u16), Box<dyn Error>> {
@@ -45,8 +44,8 @@ pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::
   let constraints = [
     Constraint::Length(greeting_height),                                                                  // Greeting
     Constraint::Length(1 + prompt_padding),                                                               // Username
-    Constraint::Length(if let Mode::Username = greeter.mode { message_height } else { 1 + prompt_padding }), // Message or answer
+    Constraint::Length(if greeter.mode == Mode::Username { message_height } else { 1 + prompt_padding }), // Message or answer
-    Constraint::Length(if let Mode::Password = greeter.mode { message_height } else { 1 }),                  // Message
+    Constraint::Length(if greeter.mode == Mode::Password { message_height } else { 1 }),                  // Message
   ];
 
   let chunks = Layout::default().direction(Direction::Vertical).constraints(constraints.as_ref()).split(frame);
@@ -66,19 +65,6 @@ pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::
   let username_value = Paragraph::new(username_value_text.iter());
 
   match greeter.mode {
-    Mode::Command => {
-      let command_label_text = [prompt_value(COMMAND)];
-      let command_label = Paragraph::new(command_label_text.iter());
-      let command_value_text = [Text::raw(&greeter.new_command)];
-      let command_value = Paragraph::new(command_value_text.iter());
-
-      f.render_widget(command_label, chunks[USERNAME_INDEX]);
-      f.render_widget(
-        command_value,
-        Rect::new(1 + chunks[USERNAME_INDEX].x + COMMAND.len() as u16, chunks[USERNAME_INDEX].y, get_input_width(greeter, COMMAND), 1),
-      );
-    }
-
     Mode::Username | Mode::Password => {
       f.render_widget(username_label, chunks[USERNAME_INDEX]);
       f.render_widget(
@@ -120,7 +106,7 @@ pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::
       }
     }
 
-    Mode::Sessions => {}
+    _ => {}
   }
 
   match greeter.mode {
@@ -140,74 +126,6 @@ pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::
       }
     }
 
-    Mode::Command => {
+    _ => Ok((1, 1)),
-      let offset = get_cursor_offset(greeter, greeter.new_command.len());
-
-      Ok((2 + cursor.x + COMMAND.len() as u16 + offset as u16, USERNAME_INDEX as u16 + cursor.y))
-    }
-
-    Mode::Sessions => Ok((1, 1)),
   }
 }
-
-fn get_height(greeter: &Greeter) -> u16 {
-  let container_padding = greeter.container_padding();
-  let prompt_padding = greeter.prompt_padding();
-  let (_, message_height) = get_message_height(greeter, 2, 0);
-  let (_, greeting_height) = get_greeting_height(greeter, 1, 0);
-
-  let initial = match greeter.mode {
-    Mode::Username | Mode::Command => (2 * container_padding) + 1,
-    Mode::Password => (2 * container_padding) + prompt_padding + 2,
-    Mode::Sessions => 0,
-  };
-
-  match greeter.mode {
-    Mode::Command => initial + greeting_height,
-    _ => initial + greeting_height + message_height,
-  }
-}
-
-fn get_greeting_height(greeter: &Greeter, padding: u16, fallback: u16) -> (Option<String>, u16) {
-  if let Some(greeting) = &greeter.greeting {
-    let width = greeter.width();
-    let wrapped = textwrap::fill(greeting, width as usize - 4);
-    let height = wrapped.trim_end().matches('\n').count();
-
-    (Some(wrapped), height as u16 + 1 + padding)
-  } else {
-    (None, fallback)
-  }
-}
-
-fn get_input_width(greeter: &Greeter, label: &str) -> u16 {
-  greeter.width() - label.len() as u16 - 4 - 1
-}
-
-fn get_message_height(greeter: &Greeter, padding: u16, fallback: u16) -> (Option<String>, u16) {
-  if let Some(message) = &greeter.message {
-    let width = greeter.width();
-    let wrapped = textwrap::fill(message.trim_end(), width as usize - 4);
-    let height = wrapped.trim_end().matches('\n').count();
-
-    (Some(wrapped), height as u16 + padding)
-  } else {
-    (None, fallback)
-  }
-}
-
-fn get_cursor_offset(greeter: &mut Greeter, length: usize) -> i16 {
-  let mut offset = length as i16 + greeter.cursor_offset;
-
-  if offset < 0 {
-    offset = 0;
-    greeter.cursor_offset = -(length as i16);
-  }
-
-  if offset > length as i16 {
-    offset = length as i16;
-    greeter.cursor_offset = 0;
-  }
-
-  offset
-}

src/ui/sessions.rs

@@ -9,6 +9,7 @@ use tui::{
   Frame,
 };
 
+use super::util::*;
 use crate::Greeter;
 
 const CHANGE_SESSION: &str = "Change session";
@@ -17,7 +18,7 @@ pub fn draw(greeter: &mut Greeter, f: &mut Frame<TermionBackend<RawTerminal<io::
   let size = f.size();
 
   let width = greeter.width();
-  let height: u16 = greeter.sessions.len() as u16 + 4;
+  let height: u16 = get_height(greeter) + greeter.sessions.len() as u16;
   let x = (size.width - width) / 2;
   let y = (size.height - height) / 2;
 

src/ui/util.rs

@@ -0,0 +1,63 @@
+use crate::{Greeter, Mode};
+
+pub fn get_height(greeter: &Greeter) -> u16 {
+  let container_padding = greeter.container_padding();
+  let prompt_padding = greeter.prompt_padding();
+  let (_, message_height) = get_message_height(greeter, 2, 0);
+  let (_, greeting_height) = get_greeting_height(greeter, 1, 0);
+
+  let initial = match greeter.mode {
+    Mode::Username | Mode::Command => (2 * container_padding) + 1,
+    Mode::Password => (2 * container_padding) + prompt_padding + 2,
+    Mode::Sessions => (2 * container_padding),
+  };
+
+  match greeter.mode {
+    Mode::Command | Mode::Sessions => initial,
+    _ => initial + greeting_height + message_height,
+  }
+}
+
+pub fn get_input_width(greeter: &Greeter, label: &str) -> u16 {
+  greeter.width() - label.len() as u16 - 4 - 1
+}
+
+pub fn get_cursor_offset(greeter: &mut Greeter, length: usize) -> i16 {
+  let mut offset = length as i16 + greeter.cursor_offset;
+
+  if offset < 0 {
+    offset = 0;
+    greeter.cursor_offset = -(length as i16);
+  }
+
+  if offset > length as i16 {
+    offset = length as i16;
+    greeter.cursor_offset = 0;
+  }
+
+  offset
+}
+
+pub fn get_greeting_height(greeter: &Greeter, padding: u16, fallback: u16) -> (Option<String>, u16) {
+  if let Some(greeting) = &greeter.greeting {
+    let width = greeter.width();
+    let wrapped = textwrap::fill(greeting, width as usize - 4);
+    let height = wrapped.trim_end().matches('\n').count();
+
+    (Some(wrapped), height as u16 + 1 + padding)
+  } else {
+    (None, fallback)
+  }
+}
+
+pub fn get_message_height(greeter: &Greeter, padding: u16, fallback: u16) -> (Option<String>, u16) {
+  if let Some(message) = &greeter.message {
+    let width = greeter.width();
+    let wrapped = textwrap::fill(message.trim_end(), width as usize - 4);
+    let height = wrapped.trim_end().matches('\n').count();
+
+    (Some(wrapped), height as u16 + padding)
+  } else {
+    (None, fallback)
+  }
+}