oop & ui experimentation

src/main.rs

@@ -1,8 +1,9 @@
 mod core;
 mod terminal;
+mod tui;
 
 fn main() {
     let lambda = core::editor::Editor::new();
     let mut screen = terminal::screen::Screen::new().unwrap();
-    terminal::tui::start(&mut screen, lambda);
+    tui::ui::Ui::run(&mut screen, lambda);
 }

src/terminal/mod.rs

@@ -1,2 +1 @@
 pub mod screen;
-pub mod tui;

src/terminal/screen.rs

@@ -11,7 +11,7 @@ pub struct Coords {
     pub y: usize,
 }
 
-// Creating a coordinates from two values
+// Creating a set of coordinates from two values
 impl Coords {
     pub fn from(x: usize, y: usize) -> Self {
         Self { x, y }

src/tui/components/mod.rs

@@ -0,0 +1,2 @@
+pub mod statusbar;
+pub mod welcome;

src/tui/components/statusbar.rs

@@ -0,0 +1,74 @@
+use crate::tui::ui::Component;
+use crate::tui::utils::with_spaces;
+use crate::core::editor::Editor;
+use crate::terminal::screen::{Coords, Screen};
+use crossterm::style::Stylize;
+
+pub struct StatusBar<'a> {
+    logo: &'a str,
+    mode: &'a str,
+    file_name: &'a str,
+}
+
+impl<'a> StatusBar<'a> {
+    pub fn new(editor: &'a Editor<'a>) -> Self {
+        Self {
+            logo: editor.config.logo,
+            mode: editor.mode.as_str(),
+            file_name: editor.buffer.name,
+        }
+    }
+}
+
+impl<'a> Component for StatusBar<'a> {
+    fn draw(&self, screen: &mut Screen, editor: &Editor) -> Result<(), ()> {
+        // Calculate where to draw the status bar
+        let status_height = screen.size.height - 2;
+
+        // Get the editor logo from the config
+        let editor_logo = &with_spaces(editor.config.logo) as &str;
+        // Get the current mode into a string
+        let mode_string = &with_spaces(editor.mode.as_str()) as &str;
+        // Get the current open file name
+        let file_name = &with_spaces(editor.buffer.name) as &str;
+
+        // Calculate the total length of all the status bar components
+        let total_length = editor_logo.len() + mode_string.len() + file_name.len() + 1;
+
+        // If the screen isn't wide enough, panic as we can't draw the status bar
+        if screen.size.width < total_length {
+            Err(())
+
+        } else {
+            // Write the editor logo
+            screen.write_at(
+                editor_logo.yellow().bold().reverse().to_string(),
+                Coords::from(0, status_height),
+            );
+
+            // Calculate where to write the current mode
+            let x = editor_logo.len() - 1;
+            // Write the current mode
+            screen.write_at(
+                mode_string.green().bold().reverse().to_string(),
+                Coords::from(x, status_height),
+            );
+            // Calculate where to write the file name
+            let x = x + mode_string.len();
+            // Write the current file name
+            screen.write_at(
+                file_name.magenta().bold().reverse().to_string(),
+                Coords::from(x, status_height),
+            );
+
+            // Draw the rest of the status bar
+            let x = x + file_name.len();
+            screen.write_at(
+                " ".repeat(screen.size.width - x).reverse().to_string(),
+                Coords::from(x, status_height),
+            );
+
+            Ok(())
+        }
+    }
+}

src/tui/components/welcome.rs

@@ -0,0 +1,40 @@
+use crate::tui::utils;
+use crate::core::editor::Editor;
+use crate::terminal::screen::{Coords, Screen};
+use crossterm::style::Stylize;
+
+pub fn draw_welcome(screen: &mut Screen, editor: &Editor) {
+    // The welcome message
+    let title = format!("{} {}", editor.config.logo, editor.config.friendly_name);
+    let message: [&str; 5] = [
+        "Hackable text editor for nerds",
+        "",
+        "Type :help to open the README.md document",
+        "Type :o <file> to open a file and edit",
+        "Type :q! or <C-c> to quit lambda",
+    ];
+
+    // If the screen is big enough, we can draw
+    if screen.size.width > utils::longest_element_in_vec(message.to_vec()) && screen.size.height > message.len() + 4 {
+        // The starting y position in the centre of the screen
+        let mut y = (screen.size.height / 2) - (message.len() / 2) - 2;
+
+        // Calculate where to place the title
+        let x = utils::calc_centered_x(screen.size.width, title.len());
+
+        // Write the title to the screen
+        screen.write_at(title.yellow().to_string(), Coords::from(x, y));
+
+        for line in message {
+            // Each line has different width so requires a different x position to center it
+            let x = utils::calc_centered_x(screen.size.width, line.len()) ;
+
+            // For each line we move downwards so increment y
+            y += 1;
+
+            // Write the line to the screen at position (x, y)
+            screen.write_at(line.to_string(), Coords::from(x, y));
+        }
+    }
+}
+

src/tui/mod.rs

@@ -0,0 +1,3 @@
+pub mod ui;
+pub mod components;
+mod utils;

src/tui/ui.rs

@@ -0,0 +1,60 @@
+use crossterm::event::{read, Event, KeyCode, KeyEvent, KeyModifiers};
+use crate::core::editor::Editor;
+use crate::terminal::screen::Screen;
+use crate::tui::components;
+
+pub trait Component {
+    fn draw(&self, screen: &mut Screen, editor: &Editor) -> Result<(), ()>;
+}
+
+struct Components {
+    bottom: Vec<Box<dyn Component>>,
+}
+
+pub struct Ui {
+    components: Components,
+}
+
+impl Ui {
+    pub fn new<'a>(editor: &'a Editor<'a>) -> Self {
+        let status_bar = components::statusbar::StatusBar::new(editor);
+
+        Self {
+            components: Components { bottom: vec![Box::new(status_bar)]},
+        }
+    }
+
+    pub fn draw(&self) {
+
+    }
+
+    pub fn run(screen: &mut Screen, editor: Editor) {
+        loop {
+            // Refresh the screen
+            screen.refresh().unwrap();
+
+            // Generate all the UI elements
+            let components = Ui::new(&editor);
+
+            // Draw all UI elements
+            components.draw();
+
+            // Check for any key presses
+            match read().unwrap() {
+                Event::Key(KeyEvent {
+                    code: KeyCode::Char('q'),
+                    modifiers: KeyModifiers::CONTROL,
+                    ..
+                }) => break,
+                Event::Key(KeyEvent {
+                    code: KeyCode::Char('c'),
+                    modifiers: KeyModifiers::CONTROL,
+                    ..
+                }) => break,
+                _ => (),
+            }
+        }
+
+        screen.exit();
+    }
+}

src/tui/utils.rs

@@ -0,0 +1,14 @@
+// Surrounds a &str with spaces
+pub fn with_spaces(text: &str) -> String {
+    format!(" {} ", text)
+}
+
+// Calculates the x coordinate for centered text
+pub fn calc_centered_x(screen_width: usize, item_length: usize) -> usize {
+    (screen_width / 2) - (item_length / 2)
+}
+
+// Finds and returns the longest element in a vector
+pub fn longest_element_in_vec(elements: Vec<&str>) -> usize {
+    elements.iter().max_by_key(|x: &&&str| x.len()).unwrap().len()
+}