at least it runs

src/main.rs

@@ -4,7 +4,7 @@ use std::fs::File;
 use std::time::{SystemTime, UNIX_EPOCH, Duration};
 use std::ops::{Add, Sub};
 use clap::Parser;
-use std::collections::HashMap;
+use chrono::DateTime;
 
 #[derive(Debug, Parser)]
 struct Flags {
@@ -48,27 +48,42 @@ fn add(f: &String, x: &Option<String>, tag: &Option<String>) -> Result<(), Strin
    Ok(())
 }
 
-#[derive(Debug, Serialize)]
+#[derive(Debug, Serialize, Clone)]
 struct Log {
    t: String,
-   d: u8,
    xs: Vec<LogX>,
 }
-#[derive(Debug, Serialize)]
+#[derive(Debug, Serialize, Clone)]
 struct LogX {
    d: u8,
    x: String,
-   xs: Vec<String>,
 }
 
 fn log(f: &String, since: &Option<String>) -> Result<(), String> {
    let since = parse_time(since)?;
    let tsheet = load(&f)?;
    let tsheet = tsheet.since(since);
-   let mut logs = HashMap::new();
-   for &x in &tsheet.xs {
+   let tsheet = tsheet.sorted();
+
+   let mut result = vec![];
+   let mut curr = Log{t: "".to_string(), xs: vec![]};
+   for x in &tsheet.xs {
+      if curr.t != x.timestamp() {
+         if curr.xs.len() > 0 {
+            result.push(curr.clone());
+         }
+         curr.xs.truncate(0);
+         curr.t = x.timestamp();
+      }
+      curr.t = x.timestamp();
+      curr.xs.push(LogX{d: 0, x: x.x.clone()});
    }
-   println!("{:?}", logs);
+   if curr.xs.len() > 0 {
+      result.push(curr.clone());
+   }
+
+   println!("{}", serde_yaml::to_string(&result).unwrap());
+
    Err("not impl".to_string())
 }
 
@@ -86,7 +101,7 @@ struct TSheet {
    xs: Vec<X>,
 }
 
-#[derive(Debug, PartialEq, Serialize, Deserialize, Clone)]
+#[derive(Debug, PartialEq, Serialize, Deserialize, Clone, Ord, Eq, PartialOrd)]
 struct X {
    t: i64,
    x: String,
@@ -165,12 +180,23 @@ impl TSheet {
    fn add(&mut self, x: String, tag: String) {
       self.xs.push(new_x(SystemTime::now(), x, tag));
    }
+
+   fn sorted(&self) -> TSheet {
+      let mut result = TSheet{xs: self.xs.clone()};
+      result.xs.sort();
+      return result;
+   }
 }
 
 impl X {
    fn ts(&self) -> SystemTime {
       UNIX_EPOCH.add(Duration::from_secs(self.t.try_into().unwrap()))
    }
+
+   fn timestamp(&self) -> String {
+      let dt = DateTime::from_timestamp(self.t, 0).unwrap();
+      dt.format("%Y-%m-%d").to_string()
+   }
 }
 
 fn new_x(t: SystemTime, x: String, tag: String) -> X {