notedeck: add debouncer util

I wanted this separate from the timed serializer so I could use it for
other things

Signed-off-by: William Casarin <jb55@jb55.com>

crates/notedeck/src/debouncer.rs

@@ -0,0 +1,35 @@
+use std::time::{Duration, Instant};
+
+/// A simple debouncer that tracks when an action was last performed
+/// and determines if enough time has passed to perform it again.
+#[derive(Debug)]
+pub struct Debouncer {
+    delay: Duration,
+    last_action: Instant,
+}
+
+impl Debouncer {
+    /// Creates a new Debouncer with the specified delay
+    pub fn new(delay: Duration) -> Self {
+        Self {
+            delay,
+            last_action: Instant::now() - delay, // Start ready to act
+        }
+    }
+
+    /// Sets a new delay value and returns self for method chaining
+    pub fn with_delay(mut self, delay: Duration) -> Self {
+        self.delay = delay;
+        self
+    }
+
+    /// Checks if enough time has passed since the last action
+    pub fn should_act(&self) -> bool {
+        self.last_action.elapsed() >= self.delay
+    }
+
+    /// Marks an action as performed, updating the timestamp
+    pub fn bounce(&mut self) {
+        self.last_action = Instant::now();
+    }
+}

crates/notedeck/src/lib.rs

@@ -2,6 +2,7 @@ mod accounts;
 mod app;
 mod args;
 mod context;
+pub mod debouncer;
 mod error;
 pub mod filter;
 pub mod fonts;

crates/notedeck/src/timed_serializer.rs

@@ -1,14 +1,13 @@
-use std::time::{Duration, Instant};
+use crate::debouncer::Debouncer;
-
 use crate::{storage, DataPath, DataPathType, Directory};
 use serde::{Deserialize, Serialize};
-use tracing::info;
+use std::time::Duration;
+use tracing::info; // Adjust this import path as needed
 
 pub struct TimedSerializer<T: PartialEq + Copy + Serialize + for<'de> Deserialize<'de>> {
     directory: Directory,
     file_name: String,
-    delay: Duration,
+    debouncer: Debouncer,
-    last_saved: Instant,
     saved_item: Option<T>,
 }
 
@@ -16,28 +15,24 @@ impl<T: PartialEq + Copy + Serialize + for<'de> Deserialize<'de>> TimedSerialize
     pub fn new(path: &DataPath, path_type: DataPathType, file_name: String) -> Self {
         let directory = Directory::new(path.path(path_type));
         let delay = Duration::from_millis(1000);
+        let debouncer = Debouncer::new(delay);
 
         Self {
             directory,
             file_name,
-            delay,
+            debouncer,
-            last_saved: Instant::now() - delay,
             saved_item: None,
         }
     }
 
     pub fn with_delay(mut self, delay: Duration) -> Self {
-        self.delay = delay;
+        self.debouncer = self.debouncer.with_delay(delay);
         self
     }
 
-    fn should_save(&self) -> bool {
-        self.last_saved.elapsed() >= self.delay
-    }
-
     // returns whether successful
     pub fn try_save(&mut self, cur_item: T) -> bool {
-        if self.should_save() {
+        if self.debouncer.should_act() {
             if let Some(saved_item) = self.saved_item {
                 if saved_item != cur_item {
                     return self.save(cur_item);
@@ -53,7 +48,6 @@ impl<T: PartialEq + Copy + Serialize + for<'de> Deserialize<'de>> TimedSerialize
         if self.saved_item.is_some() {
             return self.saved_item;
         }
-
         if let Ok(file_contents) = self.directory.get_file(self.file_name.clone()) {
             if let Ok(item) = serde_json::from_str::<T>(&file_contents) {
                 return Some(item);
@@ -61,7 +55,6 @@ impl<T: PartialEq + Copy + Serialize + for<'de> Deserialize<'de>> TimedSerialize
         } else {
             info!("Could not find file {}", self.file_name);
         }
-
         None
     }
 
@@ -75,12 +68,11 @@ impl<T: PartialEq + Copy + Serialize + for<'de> Deserialize<'de>> TimedSerialize
             .is_ok()
             {
                 info!("wrote item {}", serialized_item);
-                self.last_saved = Instant::now();
+                self.debouncer.bounce();
                 self.saved_item = Some(cur_item);
                 return true;
             }
         }
-
         false
     }
 }