Add a vim-style command line

src/ui/layout.rs

@@ -1,3 +1,4 @@
+use std::time::{SystemTime, Duration};
 use std::collections::HashMap;
 
 use cursive::align::HAlign;
@@ -7,6 +8,7 @@ use cursive::theme::ColorStyle;
 use cursive::traits::View;
 use cursive::vec::Vec2;
 use cursive::view::{IntoBoxedView, Selector};
+use cursive::views::EditView;
 use cursive::Printer;
 use unicode_width::UnicodeWidthStr;
 
@@ -20,6 +22,10 @@ pub struct Layout {
     title: String,
     statusbar: Box<dyn View>,
     focus: Option<String>,
+    pub cmdline: EditView,
+    cmdline_focus: bool,
+    error: Option<String>,
+    error_time: Option<SystemTime>,
 }
 
 impl Layout {
@@ -29,6 +35,17 @@ impl Layout {
             title: String::new(),
             statusbar: status.as_boxed_view(),
             focus: None,
+            cmdline: EditView::new().filler(" "),
+            cmdline_focus: false,
+            error: None,
+            error_time: None,
+        }
+    }
+
+    pub fn enable_cmdline(&mut self) {
+        if !self.cmdline_focus {
+            self.cmdline.set_content(":");
+            self.cmdline_focus = true;
         }
     }
 
@@ -53,11 +70,41 @@ impl Layout {
         let title = &self.views.get(&s).unwrap().title;
         self.title = title.clone();
         self.focus = Some(s);
+        self.cmdline_focus = false;
+    }
+
+    pub fn set_error<S: Into<String>>(&mut self, error: S) {
+        self.error = Some(error.into());
+        self.error_time = Some(SystemTime::now());
+    }
+
+    pub fn clear_cmdline(&mut self) {
+        self.cmdline.set_content("");
+        self.cmdline_focus = false;
+        self.error = None;
+        self.error_time = None;
+    }
+
+    fn get_error(&self) -> Option<String> {
+        if let Some(t) = self.error_time {
+            if t.elapsed().unwrap() > Duration::from_secs(5) {
+                return None;
+            }
+        }
+        self.error.clone()
     }
 }
 
 impl View for Layout {
     fn draw(&self, printer: &Printer<'_, '_>) {
+        let error = self.get_error();
+
+        let cmdline_visible = self.cmdline.get_content().len() > 0;
+        let mut cmdline_height = if cmdline_visible { 1 } else { 0 };
+        if error.is_some() {
+            cmdline_height += 1;
+        }
+
         // screen title
         printer.with_color(ColorStyle::title_primary(), |printer| {
             let offset = HAlign::Center.get_offset(self.title.width(), printer.size.x);
@@ -69,13 +116,26 @@ impl View for Layout {
             let screen = self.views.get(id).unwrap();
             let printer = &printer
                 .offset((0, 1))
-                .cropped((printer.size.x, printer.size.y - 3))
+                .cropped((printer.size.x, printer.size.y - 3 - cmdline_height))
                 .focused(true);
             screen.view.draw(printer);
         }
 
         self.statusbar
-            .draw(&printer.offset((0, printer.size.y - 2)));
+            .draw(&printer.offset((0, printer.size.y - 2 - cmdline_height)));
+
+        if let Some(e) = error {
+            printer.with_color(ColorStyle::highlight(), |printer| {
+                printer.print_hline((0, printer.size.y - cmdline_height), printer.size.x, " ");
+                printer.print((0, printer.size.y - cmdline_height), &format!("ERROR: {}", e));
+            });
+        }
+
+        if cmdline_visible {
+            let printer = &printer
+                .offset((0, printer.size.y - 1));
+            self.cmdline.draw(&printer);
+        }
     }
 
     fn required_size(&mut self, constraint: Vec2) -> Vec2 {
@@ -83,6 +143,10 @@ impl View for Layout {
     }
 
     fn on_event(&mut self, event: Event) -> EventResult {
+        if self.cmdline_focus {
+            return self.cmdline.on_event(event);
+        }
+
         if let Some(ref id) = self.focus {
             let screen = self.views.get_mut(id).unwrap();
             screen.view.on_event(event)
@@ -92,6 +156,8 @@ impl View for Layout {
     }
 
     fn layout(&mut self, size: Vec2) {
+        self.cmdline.layout(Vec2::new(size.x, 1));
+
         if let Some(ref id) = self.focus {
             let screen = self.views.get_mut(id).unwrap();
             screen.view.layout(Vec2::new(size.x, size.y - 3));
@@ -106,6 +172,10 @@ impl View for Layout {
     }
 
     fn take_focus(&mut self, source: Direction) -> bool {
+        if self.cmdline_focus {
+            return self.cmdline.take_focus(source);
+        }
+
         if let Some(ref id) = self.focus {
             let screen = self.views.get_mut(id).unwrap();
             screen.view.take_focus(source)