From 6b58daa9cda5b7ff05be3890c5588bd2d58d9f35 Mon Sep 17 00:00:00 2001
From: ddidderr <ddidderr@paul.network>
Date: Thu, 10 Mar 2022 16:42:14 +0100
Subject: [PATCH] pfs-time-measure initial commit

A library to quickly measure the time for some code.
---
 .gitignore |  2 ++
 Cargo.toml |  8 +++++
 src/lib.rs | 96 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 106 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Cargo.toml
 create mode 100644 src/lib.rs

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..96ef6c0
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+/target
+Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..d040ef2
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,8 @@
+[package]
+name = "pfs-time-measure"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..ef93cbb
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,96 @@
+use std::time::{Duration, Instant};
+
+struct Measurement {
+    start: Instant,
+    finish: Instant,
+}
+
+pub struct Clock {
+    name: String,
+    start: Option<Instant>,
+    total_duration: Duration,
+    measurements: Vec<Measurement>,
+}
+
+impl Clock {
+    pub fn new(name: String, immediately_start: bool) -> Clock {
+        let start = if immediately_start {
+            Some(Instant::now())
+        } else {
+            None
+        };
+
+        Clock {
+            name,
+            start,
+            total_duration: Duration::default(),
+            measurements: Vec::with_capacity(16),
+        }
+    }
+
+    pub fn restart(&mut self) {
+        self.start = Some(Instant::now());
+    }
+
+    pub fn stop(&mut self) -> Option<Duration> {
+        if !self.is_running() {
+            return None;
+        }
+
+        // get duration of this measurement
+        let finish = Instant::now();
+        let duration = finish.duration_since(self.start.unwrap());
+
+        // add duration to total duration
+        self.total_duration += duration;
+
+        // add measurement to list of measurements
+        self.measurements.push(Measurement {
+            start: self.start.unwrap(),
+            finish: finish,
+        });
+
+        // reset
+        self.start = None;
+
+        // return duration of this specific measurement
+        Some(duration)
+    }
+
+    pub fn stop_and_print(&mut self) {
+        match self.stop() {
+            Some(duration) => self.print_duration(duration),
+            None => println!(
+                "[CLOCK] {} cannot be stopped because timer wasn't running",
+                self.name
+            ),
+        }
+    }
+
+    fn is_running(&self) -> bool {
+        self.start.is_some()
+    }
+
+    fn print_duration(&self, duration: Duration) {
+        let name = &self.name;
+        let duration = duration.as_millis();
+        let total_duration = self.total_duration.as_millis();
+        println!("[CLOCK] {name} took {duration}ms (total {total_duration}ms)");
+    }
+
+    pub fn print_total(&self) {
+        self.print_duration(self.total_duration);
+    }
+
+    pub fn print_all_measurements(&self) {
+        for (idx, measurement) in self.measurements.iter().enumerate() {
+            println!(
+                "[CLOCK] {}/{}: {}ms",
+                self.name,
+                idx,
+                measurement.finish.duration_since(measurement.start).as_millis()
+            );
+        }
+        println!("[CLOCK] {}/total: {}ms", self.name, self.total_duration.as_millis());
+    }
+}