Merge pull request #4 from helix-editor/completion-suggestion

Completion suggestion

helix-term/src/application.rs

@@ -34,6 +34,8 @@ type Terminal = tui::Terminal<CrosstermBackend<std::io::Stdout>>;
 
 static EX: smol::Executor = smol::Executor::new();
 
+const BASE_WIDTH: u16 = 30;
+
 pub struct Application {
     editor: Editor,
     prompt: Option<Prompt>,
@@ -235,7 +237,52 @@ impl Renderer {
             .set_string(1, self.size.1 - 2, mode, self.text_color);
     }
 
-    pub fn render_prompt(&mut self, prompt: &Prompt) {
+    pub fn render_prompt(&mut self, view: &View, prompt: &Prompt) {
+        // completion
+        if !prompt.completion.is_empty() {
+            // TODO: find out better way of clearing individual lines of the screen
+            let mut row = 0;
+            let mut col = 0;
+            let max_col = self.size.0 / BASE_WIDTH;
+            let col_height = ((prompt.completion.len() as u16 + max_col - 1) / max_col);
+
+            for i in (3..col_height + 3) {
+                self.surface.set_string(
+                    0,
+                    self.size.1 - i as u16,
+                    " ".repeat(self.size.0 as usize),
+                    self.text_color,
+                );
+            }
+            self.surface.set_style(
+                Rect::new(0, self.size.1 - col_height - 2, self.size.0, col_height),
+                view.theme.get("ui.statusline"),
+            );
+            for (i, command) in prompt.completion.iter().enumerate() {
+                let color = if prompt.completion_selection_index.is_some()
+                    && i == prompt.completion_selection_index.unwrap()
+                {
+                    Style::default().bg(Color::Rgb(104, 060, 232))
+                } else {
+                    self.text_color
+                };
+                self.surface.set_stringn(
+                    1 + col * BASE_WIDTH,
+                    self.size.1 - col_height - 2 + row,
+                    &command,
+                    BASE_WIDTH as usize - 1,
+                    color,
+                );
+                row += 1;
+                if row > col_height - 1 {
+                    row = 0;
+                    col += 1;
+                }
+                if col > max_col {
+                    break;
+                }
+            }
+        }
         // render buffer text
         self.surface
             .set_string(1, self.size.1 - 1, &prompt.prompt, self.text_color);
@@ -309,10 +356,13 @@ impl Application {
 
         if let Some(view) = &mut self.editor.view {
             self.terminal.render_view(view, viewport);
-        }
-
             if let Some(prompt) = &self.prompt {
-            self.terminal.render_prompt(prompt);
+                if prompt.should_close {
+                    self.prompt = None;
+                } else {
+                    self.terminal.render_prompt(view, prompt);
+                }
+            }
         }
 
         self.terminal.draw();
@@ -383,7 +433,46 @@ impl Application {
                                 {
                                     let prompt = Prompt::new(
                                         ":".to_owned(),
-                                        |_input: &str| None, // completion
+                                        |_input: &str| {
+                                            // TODO: i need this duplicate list right now to avoid borrow checker issues
+                                            let command_list = vec![
+                                                String::from("q"),
+                                                String::from("aaa"),
+                                                String::from("bbb"),
+                                                String::from("ccc"),
+                                                String::from("ddd"),
+                                                String::from("eee"),
+                                                String::from("averylongcommandaverylongcommandaverylongcommandaverylongcommandaverylongcommand"),
+                                                String::from("q"),
+                                                String::from("aaa"),
+                                                String::from("bbb"),
+                                                String::from("ccc"),
+                                                String::from("ddd"),
+                                                String::from("eee"),
+                                                String::from("q"),
+                                                String::from("aaa"),
+                                                String::from("bbb"),
+                                                String::from("ccc"),
+                                                String::from("ddd"),
+                                                String::from("eee"),
+                                                String::from("q"),
+                                                String::from("aaa"),
+                                                String::from("bbb"),
+                                                String::from("ccc"),
+                                                String::from("ddd"),
+                                                String::from("eee"),
+                                                String::from("q"),
+                                                String::from("aaa"),
+                                                String::from("bbb"),
+                                                String::from("ccc"),
+                                                String::from("ddd"),
+                                                String::from("eee"),
+                                            ];
+                                            command_list
+                                                .into_iter()
+                                                .filter(|command| command.contains(_input))
+                                                .collect()
+                                        }, // completion
                                         |editor: &mut Editor, input: &str| match input {
                                             "q" => editor.should_close = true,
                                             _ => (),

helix-view/src/commands.rs

@@ -307,23 +307,12 @@ pub fn append_mode(view: &mut View, _count: usize) {
     })
 }
 
-pub fn command_mode(_view: &mut View, _count: usize) {
+// TODO: I, A, o and O can share a lot of the primitives.
-    use crate::Editor;
-
-    let prompt = Prompt::new(
-        ":".to_owned(),
-        |_input: &str| None, // completion
-        |editor: &mut Editor, input: &str| match input {
-            "q" => editor.should_close = true,
-            _ => (),
-        },
-    );
 
-    // set_prompt(prompt)
+pub fn command_mode(_view: &mut View, _count: usize) {
+    unimplemented!()
 }
 
-// TODO: I, A, o and O can share a lot of the primitives.
-
 // calculate line numbers for each selection range
 fn selection_lines(state: &State) -> Vec<usize> {
     let mut lines = state

helix-view/src/prompt.rs

@@ -1,5 +1,4 @@
-use crate::commands;
+use crate::Editor;
-use crate::{Editor, View};
 use crossterm::event::{KeyCode, KeyEvent, KeyModifiers};
 use std::string::String;
 
@@ -7,20 +6,26 @@ pub struct Prompt {
     pub prompt: String,
     pub line: String,
     pub cursor: usize,
-    completion_fn: Box<dyn FnMut(&str) -> Option<Vec<&str>>>,
+    pub completion: Vec<String>,
+    pub should_close: bool,
+    pub completion_selection_index: Option<usize>,
+    completion_fn: Box<dyn FnMut(&str) -> Vec<String>>,
     callback_fn: Box<dyn FnMut(&mut Editor, &str)>,
 }
 
 impl Prompt {
     pub fn new(
         prompt: String,
-        completion_fn: impl FnMut(&str) -> Option<Vec<&str>> + 'static,
+        mut completion_fn: impl FnMut(&str) -> Vec<String> + 'static,
         callback_fn: impl FnMut(&mut Editor, &str) + 'static,
     ) -> Prompt {
         Prompt {
             prompt,
             line: String::new(),
             cursor: 0,
+            completion: completion_fn(""),
+            should_close: false,
+            completion_selection_index: None,
             completion_fn: Box::new(completion_fn),
             callback_fn: Box::new(callback_fn),
         }
@@ -29,10 +34,12 @@ impl Prompt {
     pub fn insert_char(&mut self, c: char) {
         self.line.insert(self.cursor, c);
         self.cursor += 1;
+        self.completion = (self.completion_fn)(&self.line);
+        self.exit_selection();
     }
 
     pub fn move_char_left(&mut self) {
-        if self.cursor > 1 {
+        if self.cursor > 0 {
             self.cursor -= 1;
         }
     }
@@ -55,7 +62,22 @@ impl Prompt {
         if self.cursor > 0 {
             self.line.remove(self.cursor - 1);
             self.cursor -= 1;
+            self.completion = (self.completion_fn)(&self.line);
+        }
+        self.exit_selection();
+    }
+
+    pub fn change_completion_selection(&mut self) {
+        if self.completion.is_empty() {
+            return;
+        }
+        let index =
+            self.completion_selection_index.map(|i| i + 1).unwrap_or(0) % self.completion.len();
+        self.completion_selection_index = Some(index);
+        self.line = self.completion[index].clone();
     }
+    pub fn exit_selection(&mut self) {
+        self.completion_selection_index = None;
     }
 
     pub fn handle_input(&mut self, key_event: KeyEvent, editor: &mut Editor) {
@@ -66,7 +88,7 @@ impl Prompt {
             } => self.insert_char(c),
             KeyEvent {
                 code: KeyCode::Esc, ..
-            } => unimplemented!("Exit prompt!"),
+            } => self.should_close = true,
             KeyEvent {
                 code: KeyCode::Right,
                 ..
@@ -85,12 +107,19 @@ impl Prompt {
             } => self.move_start(),
             KeyEvent {
                 code: KeyCode::Backspace,
-                ..
+                modifiers: KeyModifiers::NONE,
             } => self.delete_char_backwards(),
             KeyEvent {
                 code: KeyCode::Enter,
                 ..
             } => (self.callback_fn)(editor, &self.line),
+            KeyEvent {
+                code: KeyCode::Tab, ..
+            } => self.change_completion_selection(),
+            KeyEvent {
+                code: KeyCode::Char('q'),
+                modifiers: KeyModifiers::CONTROL,
+            } => self.exit_selection(),
             _ => (),
         }
     }