Write out status to file (resolves #6)

src/main.rs

@@ -1,6 +1,7 @@
 use anyhow::Result;
+use shellexpand;
 use std::collections::HashMap;
-use std::io::stdout;
+use std::io::{stdout, Write};
 use std::rc::Rc;
 use std::time::{Duration, Instant};
 mod constants;
@@ -137,6 +138,36 @@ impl App {
         self.session_ratings = session_stats_as_vec(&self.session_stats);
     }
 
+    fn cleanup(&self) {
+        let path = shellexpand::tilde(constants::STATUS_FILE).to_string();
+        let _ = std::fs::remove_file(path);
+    }
+
+    fn write_status(&self) {
+        let status = match self.state {
+            State::InProgress => format!(
+                "{} - {}",
+                self.user_intention,
+                duration_as_str(&self.session_remaining)
+            ),
+            State::Paused => format!(
+                "antidrift paused - {}",
+                duration_as_str(&self.session_remaining)
+            ),
+            _ => format!("antidrift inactive"),
+        };
+
+        let path = shellexpand::tilde(constants::STATUS_FILE).to_string();
+        if let Ok(mut file) = std::fs::OpenOptions::new()
+            .write(true)
+            .create(true)
+            .truncate(true)
+            .open(&path)
+        {
+            let _ = file.write_all(status.as_bytes());
+        }
+    }
+
     fn tick_50ms(&mut self) {
         match self.state {
             State::InputIntention | State::InputDuration => {
@@ -172,6 +203,7 @@ impl App {
 
     fn tick_1s(&mut self) {
         self.last_tick_1s = Instant::now();
+        self.write_status();
 
         if self.state == State::Paused {
             self.user_duration = self.user_duration.saturating_add(Duration::from_secs(1));
@@ -261,6 +293,7 @@ fn main() -> Result<()> {
         app.handle_ticks();
     }
 
+    app.cleanup();
     disable_raw_mode()?;
     stdout().execute(LeaveAlternateScreen)?;
     Ok(())
@@ -450,7 +483,7 @@ fn ui(frame: &mut Frame, app: &App) {
         spans.push(span);
     }
 
-    if app.user_duration == Duration::ZERO {
+    if app.user_duration.is_zero() {
         let span = Span::styled(
             constants::PROVIDE_VALID_DURATION,
             Style::new().fg(Color::LightRed),