server: Only write CSV headers when initially creating the log file

[tattlekey] / server / src / main.rs

diff --git a/server/src/main.rs b/server/src/main.rs
index c31f873ba08a103cc0e6a2f856b2bb8a3debf44b..573edc580a8a99fc1671e37cb9cb90f6df108c88 100644 (file)
--- a/server/src/main.rs
+++ b/server/src/main.rs
@@ -14,12 +14,15 @@
 // You should have received a copy of the GNU General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
+use serde::Serialize;
+use std::collections::HashMap;
 use std::net::UdpSocket;
 use std::time::{Duration, SystemTime};
 
 const MESSAGE_SIZE: usize = 12;
+const LOGFILENAME: &str = "log.csv";
 
-#[derive(Debug)]
+#[derive(Eq, Debug, Hash, PartialEq, Serialize)]
 struct MessageKey {
     epoch: u32,
     device: u16,
@@ -29,7 +32,6 @@ struct MessageKey {
 #[derive(Debug)]
 struct Message {
     key: MessageKey,
-    ago: u32,
     t: SystemTime,
 }
 
@@ -42,7 +44,6 @@ impl From<&[u8; MESSAGE_SIZE]> for Message {
                 device: u16::from_be_bytes(value[4..=5].try_into().expect("I can't count")),
                 seq: u16::from_be_bytes(value[6..=7].try_into().expect("I can't count")),
             },
-            ago,
             t: SystemTime::now() - Duration::new(ago.into(), 0),
         }
     }
@@ -57,7 +58,39 @@ impl TryFrom<&[u8]> for Message {
     }
 }
 
+#[derive(Debug)]
+struct Range {
+    start: SystemTime,
+    end: SystemTime,
+}
+impl Range {
+    fn new(t: &SystemTime) -> Self {
+        Self { start: *t, end: *t }
+    }
+    fn contains(&self, t: &SystemTime) -> bool {
+        t > &self.start && t < &self.end
+    }
+    fn extend(&mut self, t: &SystemTime) {
+        if t < &self.start {
+            self.start = *t;
+        }
+        if t > &self.end {
+            self.end = *t;
+        }
+    }
+}
+
 fn main() {
+    let log_file_exists = std::path::Path::new(LOGFILENAME).exists();
+    let logfile = std::fs::OpenOptions::new()
+        .create_new(!log_file_exists)
+        .append(true)
+        .open(LOGFILENAME)
+        .expect("Coudln't open log file");
+    let mut log = csv::WriterBuilder::new()
+        .has_headers(!log_file_exists)
+        .from_writer(logfile);
+    let mut presses = HashMap::<MessageKey, Range>::new();
     let socket = UdpSocket::bind("0.0.0.0:29803").expect("couldn't bind to address");
     loop {
         let mut buf = [0; MESSAGE_SIZE];
@@ -70,7 +103,16 @@ fn main() {
                     continue;
                 }
                 let message = Message::try_from(filled_buf).expect("I can't count");
-                println!("Got packet from {src_addr}: {message:?}");
+                log.serialize((&message.key, message.t))
+                    .expect("Couldn't write log");
+                log.flush().expect("Couldn't flush log");
+                if let Some(r) = presses.get_mut(&message.key) {
+                    if !r.contains(&message.t) {
+                        r.extend(&message.t);
+                    }
+                } else {
+                    presses.insert(message.key, Range::new(&message.t));
+                }
             }
         }
     }