1 files changed, 161 insertions, 0 deletions
diff --git a/src/state/readline.rs b/src/state/readline.rs
new file mode 100644
index 0000000..585d6b6
--- /dev/null
+++ b/src/state/readline.rs
@@ -0,0 +1,161 @@
+use unicode_width::{UnicodeWidthChar as _, UnicodeWidthStr as _};
+
+pub struct Readline {
+    size: (u16, u16),
+    input_line: String,
+    pos: usize,
+}
+
+impl Readline {
+    pub fn new() -> Self {
+        Self {
+            size: (24, 80),
+            input_line: "".into(),
+            pos: 0,
+        }
+    }
+
+    pub async fn render(
+        &self,
+        out: &mut impl textmode::Textmode,
+        entry_count: usize,
+        focus: bool,
+        offset: time::UtcOffset,
+    ) -> anyhow::Result<()> {
+        let pwd = crate::env::pwd()?;
+        let user = crate::env::user()?;
+        let hostname = crate::env::hostname()?;
+        let time = crate::env::time(offset)?;
+        let prompt_char = crate::env::prompt_char()?;
+
+        let id = format!("{}@{}", user, hostname);
+        let idlen: u16 = id.len().try_into().unwrap();
+        let timelen: u16 = time.len().try_into().unwrap();
+
+        out.move_to(self.size.0 - 2, 0);
+        if focus {
+            out.set_bgcolor(textmode::Color::Rgb(32, 32, 64));
+        } else {
+            out.set_bgcolor(textmode::Color::Rgb(32, 32, 32));
+        }
+        out.write(b"\x1b[K");
+        out.set_fgcolor(textmode::color::YELLOW);
+        out.write_str(&format!("{}", entry_count + 1));
+        out.reset_attributes();
+        if focus {
+            out.set_bgcolor(textmode::Color::Rgb(32, 32, 64));
+        } else {
+            out.set_bgcolor(textmode::Color::Rgb(32, 32, 32));
+        }
+        out.write_str(" (");
+        out.write_str(&pwd);
+        out.write_str(")");
+        out.move_to(self.size.0 - 2, self.size.1 - 4 - idlen - timelen);
+        out.write_str(&id);
+        out.write_str(" [");
+        out.write_str(&time);
+        out.write_str("]");
+
+        out.move_to(self.size.0 - 1, 0);
+        out.reset_attributes();
+        out.write_str(&prompt_char);
+        out.write_str(" ");
+        out.reset_attributes();
+        out.write(b"\x1b[K");
+        out.write_str(&self.input_line);
+        out.reset_attributes();
+        out.move_to(self.size.0 - 1, 2 + self.pos_width());
+        if focus {
+            out.hide_cursor(false);
+        }
+        Ok(())
+    }
+
+    pub async fn resize(&mut self, size: (u16, u16)) {
+        self.size = size;
+    }
+
+    pub fn lines(&self) -> usize {
+        2 // XXX handle wrapping
+    }
+
+    pub fn input(&self) -> String {
+        self.input_line.clone()
+    }
+
+    pub fn add_input(&mut self, s: &str) {
+        self.input_line.insert_str(self.byte_pos(), s);
+        self.pos += s.chars().count();
+    }
+
+    pub fn set_input(&mut self, s: &str) {
+        self.input_line = s.to_string();
+        self.pos = s.chars().count();
+    }
+
+    pub fn backspace(&mut self) {
+        while self.pos > 0 {
+            self.pos -= 1;
+            let width =
+                self.input_line.remove(self.byte_pos()).width().unwrap_or(0);
+            if width > 0 {
+                break;
+            }
+        }
+    }
+
+    pub fn clear_input(&mut self) {
+        self.input_line.clear();
+        self.pos = 0;
+    }
+
+    pub fn clear_backwards(&mut self) {
+        self.input_line = self.input_line.chars().skip(self.pos).collect();
+        self.pos = 0;
+    }
+
+    pub fn cursor_left(&mut self) {
+        if self.pos == 0 {
+            return;
+        }
+        self.pos -= 1;
+        while let Some(c) = self.input_line.chars().nth(self.pos) {
+            if c.width().unwrap_or(0) == 0 {
+                self.pos -= 1;
+            } else {
+                break;
+            }
+        }
+    }
+
+    pub fn cursor_right(&mut self) {
+        if self.pos == self.input_line.chars().count() {
+            return;
+        }
+        self.pos += 1;
+        while let Some(c) = self.input_line.chars().nth(self.pos) {
+            if c.width().unwrap_or(0) == 0 {
+                self.pos += 1;
+            } else {
+                break;
+            }
+        }
+    }
+
+    fn pos_width(&self) -> u16 {
+        self.input_line
+            .chars()
+            .take(self.pos)
+            .collect::<String>()
+            .width()
+            .try_into()
+            .unwrap()
+    }
+
+    fn byte_pos(&self) -> usize {
+        self.input_line
+            .char_indices()
+            .nth(self.pos)
+            .map_or(self.input_line.len(), |(i, _)| i)
+    }
+}