Keep a database of timers

src-tauri/src/main.rs

@@ -3,13 +3,34 @@
     windows_subsystem = "windows"
 )]
 
-use std::time::{Duration, Instant};
+use std::{
+    collections::HashMap,
+    sync::{Arc, Mutex},
+    time::{Duration, Instant}, fmt, error::Error,
+};
 
 use chrono::{DateTime, FixedOffset, Local};
-use tauri::{async_runtime::spawn, Window};
+use tauri::{State, Window, async_runtime::spawn};
 use tokio::time::interval;
 use uuid::Uuid;
 
+#[derive(serde::Serialize, Debug)]
+enum TimerError {
+    NotFound,
+    NotStarted,
+}
+
+impl fmt::Display for TimerError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            TimerError::NotFound => write!(f, "timer not found"),
+            TimerError::NotStarted => write!(f, "timer not started"),
+        }
+    }
+}
+
+impl Error for TimerError {}
+
 #[derive(Clone, Default, serde::Serialize)]
 struct Timer {
     id: Uuid,
@@ -17,6 +38,8 @@ struct Timer {
     duration: Duration,
     elapsed: Option<Duration>,
     message: String,
+    #[serde(skip)]
+    checked: Option<Instant>,
 }
 
 impl Timer {
@@ -33,52 +56,119 @@ impl Timer {
         self.elapsed.map_or(false, |e| e >= self.duration)
     }
 
-    async fn run(&mut self, window: Window) {
+    fn start(self) -> Self {
-        self.started = Some(Local::now().into());
+        Timer {
-        let mut elapsed = Duration::from_secs(0);
+            started: Some(Local::now().into()),
-        self.elapsed = Some(elapsed);
+            elapsed: Some(Duration::from_secs(0)),
-        let mut last_checked = Instant::now();
+            checked: Some(Instant::now()),
-
+            ..self
-        let mut interval = interval(Duration::from_secs(1) / 60);
-        loop {
-            interval.tick().await;
-            let now = Instant::now();
-            let duration = now - last_checked;
-
-            elapsed += duration;
-            self.elapsed = Some(elapsed);
-
-            if self.complete() {
-                break;
-            }
-
-            if window.emit("timer-tick", self.clone()).is_err() {
-                break;
-            }
-            last_checked = now;
         }
+    }
 
-        window
+    fn tick(self) -> Result<Self, TimerError> {
-            .emit("timer-done", self.clone())
+        let now = Instant::now();
-            .expect("Our window went away?");
+        let elapsed = now - match self.checked {
+            None => return Err(TimerError::NotStarted),
+            Some(checked) => checked,
+        };
+
+        Ok(Timer {
+            elapsed: self.elapsed.map(|e| e + elapsed),
+            checked: Some(now),
+            ..self
+        })
     }
 }
 
+#[derive(Default)]
+struct Timers(Arc<Mutex<HashMap<Uuid, Timer>>>);
+
+impl Timers {
+    fn make_timer(&self, duration: Duration, message: &str) -> Timer {
+        let timer = Timer::new(message, duration);
+
+        self.0.lock().unwrap().insert(timer.id, timer.clone());
+
+        timer
+    }
+
+    fn delete_timer(&self, timer_id: Uuid) -> Option<Timer> {
+        self.0.lock().unwrap().get(&timer_id).cloned()
+    }
+
+    fn start_timer(&self, timer_id: Uuid) -> Result<Timer, TimerError> {
+        let mut timers = self.0.lock().unwrap();
+        match timers.get(&timer_id).cloned() {
+            None => Err(TimerError::NotFound),
+            Some(t) => {
+                let started = t.start();
+                timers.insert(started.id, started.clone());
+
+                Ok(started)
+            }
+        }
+    }
+
+    fn tick_timer(&self, timer_id: Uuid) -> Result<Timer, TimerError> {
+        let mut timers = self.0.lock().unwrap();
+        match timers.get(&timer_id).cloned() {
+            None => Err(TimerError::NotFound),
+            Some(t) => {
+                let started = t.tick()?;
+                timers.insert(started.id, started.clone());
+
+                Ok(started)
+            }
+        }
+    }
+
+}
+
 #[tauri::command]
-fn start_timer(window: Window, duration: Duration, message: &str) -> Uuid {
+fn make_timer(timers: State<'_, Timers>, duration: Duration, message: &str) -> Timer {
-    let mut timer = Timer::new(message, duration);
+    timers.make_timer(duration, message)
-    let timer_id = timer.id;
+}
+
+#[tauri::command]
+fn delete_timer(timers: State<'_, Timers>, timer_id: Uuid) -> Option<Timer> {
+    timers.delete_timer(timer_id)
+}
+
+#[tauri::command]
+fn start_timer(window: Window, timers: State<'_, Timers>, timer_id: Uuid) -> Result<Timer, TimerError> {
+    let timers = Timers(timers.0.to_owned());
+    let timer = timers.start_timer(timer_id)?;
+    let res = timer.clone();
 
     spawn(async move {
-        timer.run(window).await;
+        let mut interval = interval(Duration::from_secs(1) / 60);
+        
+        loop {
+            interval.tick().await;
+            match timers.tick_timer(timer_id) {
+                Err(_) => break,
+                Ok(timer) => {
+                    if timer.complete() || window.emit("timer-tick", timer).is_err() {
+                        break;
+                    }
+                }
+            }
+        }
+
+        window.emit("timer-done", timer).ok();
     });
 
-    timer_id
+    Ok(res)
 }
 
 fn main() {
     tauri::Builder::default()
-        .invoke_handler(tauri::generate_handler![start_timer])
+        .manage(Timers(Default::default()))
+        .invoke_handler(tauri::generate_handler![
+            delete_timer,
+            make_timer,
+            start_timer
+        ])
         .run(tauri::generate_context!())
         .expect("error while running tauri application");
 }

src/App.svelte

@@ -1,3 +1,7 @@
+<!--
+ Copyright 2022 ModZero.
+ SPDX-License-Identifier: 	AGPL-3.0-or-later
+-->
 <script type="ts">
   import { onDestroy, onMount } from "svelte";
   import type { UnlistenFn } from "@tauri-apps/api/event";
@@ -5,8 +9,8 @@
   import { listen } from "@tauri-apps/api/event";
 
   let seconds = 5;
-  let timer_tick_unlisten: Promise<UnlistenFn> | null = null;
+  let timerTickUnlisten: Promise<UnlistenFn> | null = null;
-  let timer_done_unlisten: Promise<UnlistenFn> | null = null;
+  let timerDoneUnlisten: Promise<UnlistenFn> | null = null;
 
   type Timer = {
     id: string;
@@ -17,32 +21,58 @@
   };
 
   onMount(() => {
-    timer_tick_unlisten = listen<Timer>("timer-tick", (event) => {
+    timerTickUnlisten = listen<Timer>("timer-tick", (event) => {
       console.log("Tick!", event.payload.id, event.payload.elapsed);
     });
 
-    timer_done_unlisten = listen<Timer>("timer-done", (event) => {
+    timerDoneUnlisten = listen<Timer>("timer-done", (event) => {
       console.log("Done!", event.payload.id);
     });
+    
   });
 
   onDestroy(() => {
-    timer_tick_unlisten?.then((ttu) => ttu());
+    timerTickUnlisten?.then((ttu) => ttu());
-    timer_done_unlisten?.then((tdu) => tdu());
+    timerDoneUnlisten?.then((tdu) => tdu());
   });
 
-  function start_timer() {
+  async function startTimer() {
-    invoke("start_timer", {
+    let timer = await invoke<Timer>("make_timer", {
       duration: { secs: seconds, nanos: 0 },
       message: "Hi!",
     });
+    invoke("start_timer", { timerId: timer.id });
   }
 </script>
 
 <main>
-  <label>
+  <div id="timer" />
-    Fire after
+  <div id="controls">
-    <input type="number" bind:value={seconds} />
+    <label>
-  </label>
+      Fire after
-  <button on:click={start_timer}>Fire!</button>
+      <input type="number" bind:value={seconds} />
+    </label>
+    <button on:click={startTimer}>Fire!</button>
+  </div>
 </main>
+
+<style>
+  main {
+    position: fixed;
+    top: 0px;
+    left: 0px;
+    right: 0px;
+    bottom: 0px;
+    display: flex;
+    flex-direction: column;
+  }
+  #timer {
+    flex-grow: 1;
+    margin: 0.5em;
+  }
+
+  #controls {
+    margin: 0.5em;
+    padding: 0.5em;
+  }
+</style>

src/app.css

@@ -1,5 +1,5 @@
 :root {
-  font-family: Inter, Avenir, Helvetica, Arial, sans-serif;
+  font-family: Helvetica, Arial, sans-serif;
   font-size: 16px;
   line-height: 24px;
   font-weight: 400;
@@ -26,7 +26,6 @@ a:hover {
 
 body {
   margin: 0;
-  display: flex;
   place-items: center;
   min-width: 320px;
   min-height: 100vh;
@@ -37,45 +36,15 @@ h1 {
   line-height: 1.1;
 }
 
-.card {
-  padding: 2em;
-}
 
 #app {
+  position: absolute;
   max-width: 1280px;
-  margin: 0 auto;
+  margin: 0 0;
   padding: 2rem;
   text-align: center;
-}
+  top: 0;
-
+  bottom: 0;
-button {
+  left: 0;
-  border-radius: 8px;
+  right: 0;
-  border: 1px solid transparent;
-  padding: 0.6em 1.2em;
-  font-size: 1em;
-  font-weight: 500;
-  font-family: inherit;
-  background-color: #1a1a1a;
-  cursor: pointer;
-  transition: border-color 0.25s;
-}
-button:hover {
-  border-color: #646cff;
-}
-button:focus,
-button:focus-visible {
-  outline: 4px auto -webkit-focus-ring-color;
-}
-
-@media (prefers-color-scheme: light) {
-  :root {
-    color: #213547;
-    background-color: #ffffff;
-  }
-  a:hover {
-    color: #747bff;
-  }
-  button {
-    background-color: #f9f9f9;
-  }
 }

src/main.ts

@@ -1,3 +1,7 @@
+// Copyright 2022 ModZero.
+// SPDX-License-Identifier: 	AGPL-3.0-or-later
+
+
 import "./app.css";
 import App from "./App.svelte";