Merge branch 'main' into dev

2 files changed, 176 insertions, 0 deletions

diff --git a/src/ui/widgets/mod.rs b/src/ui/widgets/mod.rs
index 6319d91..12e65b4 100644
--- a/src/ui/widgets/mod.rs
+++ b/src/ui/widgets/mod.rs
@@ -2,6 +2,7 @@ mod tui_dirlist;
 mod tui_dirlist_detailed;
 mod tui_file_preview;
 mod tui_footer;
+mod tui_help;
 mod tui_menu;
 mod tui_prompt;
 mod tui_tab;
@@ -13,6 +14,7 @@ pub use self::tui_dirlist::TuiDirList;
 pub use self::tui_dirlist_detailed::{trim_file_label, TuiDirListDetailed};
 pub use self::tui_file_preview::TuiFilePreview;
 pub use self::tui_footer::TuiFooter;
+pub use self::tui_help::{get_keymap_table, TuiHelp};
 pub use self::tui_menu::TuiMenu;
 pub use self::tui_prompt::TuiPrompt;
 pub use self::tui_tab::TuiTabBar;
diff --git a/src/ui/widgets/tui_help.rs b/src/ui/widgets/tui_help.rs
new file mode 100644
index 0000000..da4f6ed
--- /dev/null
+++ b/src/ui/widgets/tui_help.rs
@@ -0,0 +1,174 @@
+use tui::buffer::Buffer;
+use tui::layout::{Constraint, Rect};
+use tui::style::{Color, Modifier, Style};
+use tui::widgets::{Cell, Row, Table, Widget};
+
+use crate::commands::CommandKeybind;
+use crate::config::AppKeyMapping;
+use termion::event::{Event, Key};
+
+use lazy_static::lazy_static;
+
+lazy_static! {
+    static ref COMMENT_STYLE: Style = Style::default().add_modifier(Modifier::REVERSED);
+    static ref DEFAULT_STYLE: Style = Style::default();
+    static ref HEADER_STYLE: Style = Style::default().fg(Color::Yellow);
+    static ref KEY_STYLE: Style = Style::default().fg(Color::Green);
+    static ref COMMAND_STYLE: Style = Style::default().fg(Color::Blue);
+}
+
+const TITLE: &str = "Keybindings";
+const FOOTER: &str = "Press <ESC> to return, / to search, 1,2,3 to sort";
+
+pub struct TuiHelp<'a> {
+    // This keymap is constructed with get_keymap_table function
+    keymap: &'a Vec<Row<'a>>,
+    offset: &'a mut u8,
+    search_query: &'a str,
+}
+
+impl<'a> TuiHelp<'a> {
+    pub fn new(keymap: &'a Vec<Row>, offset: &'a mut u8, search_query: &'a str) -> TuiHelp<'a> {
+        TuiHelp {
+            keymap,
+            offset,
+            search_query,
+        }
+    }
+}
+
+impl<'a> Widget for TuiHelp<'a> {
+    fn render(self, area: Rect, buf: &mut Buffer) {
+        // Subtracting 2 because we'll draw a title at the top and some
+        // additional information at the bottom of the page
+        let height = (area.bottom() - area.top() - 2) as i16;
+        let width = area.right() - area.left();
+        let max_offset = Ord::max(self.keymap.len() as i16 - height + 2, 0) as u8;
+        if *self.offset > max_offset {
+            *self.offset = max_offset;
+        }
+        let keymap = Vec::from(&self.keymap[(*self.offset as usize)..]);
+
+        let keybindings_area = Rect::new(0, 1, width, height as u16);
+        let mut keybindings_buffer = Buffer::default();
+        keybindings_buffer.resize(keybindings_area);
+        let widths = [
+            Constraint::Length((width as f32 * 0.12) as u16),
+            Constraint::Length((width as f32 * 0.50) as u16),
+            Constraint::Length((width as f32 * 0.38) as u16),
+        ];
+        let table_widget = Table::new(keymap)
+            .header(
+                Row::new(vec!["Key", "Command", "Description"])
+                    .style(*HEADER_STYLE)
+                    .bottom_margin(1),
+            )
+            .widths(&widths)
+            .column_spacing(1);
+
+        table_widget.render(keybindings_area, &mut keybindings_buffer);
+        buf.merge(&keybindings_buffer);
+        buf.set_stringn(
+            0,
+            0,
+            format!("{:^w$}", TITLE, w = width as usize),
+            width as usize,
+            *COMMENT_STYLE,
+        );
+
+        let footer = if self.search_query.is_empty() {
+            format!("{:^w$}", FOOTER, w = width as usize)
+        } else {
+            format!("{:<w$}", self.search_query, w = width as usize)
+        };
+        buf.set_stringn(
+            0,
+            (height + 1) as u16,
+            &footer,
+            footer.len(),
+            *COMMENT_STYLE,
+        );
+    }
+}
+
+// Translates output from 'get_raw_keymap_table' into format,
+// readable by TUI table widget
+pub fn get_keymap_table<'a>(
+    keymap: &'a AppKeyMapping,
+    search_query: &'a str,
+    sort_by: usize,
+) -> Vec<Row<'a>> {
+    let raw_rows = get_raw_keymap_table(keymap, search_query, sort_by);
+    let mut rows = Vec::new();
+    for row in raw_rows {
+        rows.push(Row::new(vec![
+            Cell::from(row[0].clone()).style(*KEY_STYLE),
+            Cell::from(row[1].clone()).style(*COMMAND_STYLE),
+            Cell::from(row[2].clone()).style(*DEFAULT_STYLE),
+        ]));
+    }
+    rows
+}
+
+// This function is needed because we cannot access Row items, which
+// means that we won't be able to sort binds if we create Rows directly
+pub fn get_raw_keymap_table<'a>(
+    keymap: &'a AppKeyMapping,
+    search_query: &'a str,
+    sort_by: usize,
+) -> Vec<[String; 3]> {
+    let mut rows = Vec::new();
+    for (event, bind) in keymap.as_ref() {
+        let key = key_event_to_string(event);
+        let (command, comment) = match bind {
+            CommandKeybind::SimpleKeybind(command) => (format!("{}", command), command.comment()),
+            CommandKeybind::CompositeKeybind(sub_keymap) => {
+                let mut sub_rows = get_raw_keymap_table(sub_keymap, "", sort_by);
+                for _ in 0..sub_rows.len() {
+                    let mut sub_row = sub_rows.pop().unwrap();
+                    sub_row[0] = key.clone() + &sub_row[0];
+                    if sub_row[0].contains(search_query) || sub_row[1].contains(search_query) {
+                        rows.push(sub_row)
+                    }
+                }
+                continue;
+            }
+        };
+        if key.contains(search_query) || command.contains(search_query) {
+            rows.push([key, command, comment.to_string()]);
+        }
+    }
+    rows.sort_by_cached_key(|x| x[sort_by].clone());
+    rows
+}
+
+fn key_event_to_string(event: &Event) -> String {
+    match event {
+        Event::Key(key) => match key {
+            Key::Backspace => "Backspace".to_string(),
+            Key::Left => "Left".to_string(),
+            Key::Right => "Right".to_string(),
+            Key::Up => "Up".to_string(),
+            Key::Down => "Down".to_string(),
+            Key::Home => "Home".to_string(),
+            Key::End => "End".to_string(),
+            Key::PageUp => "PageUp".to_string(),
+            Key::PageDown => "PageDown".to_string(),
+            Key::BackTab => "BackTab".to_string(),
+            Key::Delete => "Delete".to_string(),
+            Key::Insert => "Insert".to_string(),
+            Key::Esc => "Esc".to_string(),
+            Key::F(n) => format!("F{}", n),
+            Key::Char(chr) => match chr {
+                ' ' => "Space".to_string(),
+                '\t' => "Tab".to_string(),
+                '\n' => "Enter".to_string(),
+                chr => chr.to_string(),
+            },
+            Key::Alt(chr) => format!("Alt+{}", chr),
+            Key::Ctrl(chr) => format!("Ctrl+{}", chr),
+            _ => "".to_string(),
+        },
+        _ => "".to_string(),
+    }
+}