getting latest file with window

src/todo/file.rs

@@ -1,18 +1,22 @@
 use chrono::naive::NaiveDate;
 use regex::Regex;
+use std::cmp::min;
 use std::convert::TryFrom;
 use std::fs::DirEntry;
+use std::path::PathBuf;
 use std::str::FromStr;
 
-#[derive(Debug)]
+use crate::file::FileNameParseError;
+
+#[derive(Debug, Clone, PartialEq)]
 pub struct File {
-    pub file: DirEntry,
+    pub file: PathBuf,
     pub date: NaiveDate,
 }
 
-pub enum FileError{
+pub enum FileError {
     //IOError(&'static str),
-    ParseError(&'static str)
+    ParseError(&'static str),
 }
 
 impl File {
@@ -46,13 +50,13 @@ impl TryFrom<DirEntry> for File {
 
     fn try_from(direntry: DirEntry) -> Result<Self, Self::Error> {
         let re = File::get_file_regex();
-//        println!("{:?}", re);
+        //        println!("{:?}", re);
         let file_name = direntry.file_name();
         let file_name_str = match file_name.to_str() {
             Some(name) => name,
             _ => "",
         };
-//        println!("{:?}", file_name_str);
+        //        println!("{:?}", file_name_str);
 
         if let Some(caps) = re.captures(file_name_str) {
             let year: i32 = Self::capture_as_number(&caps, "year").unwrap();
@@ -60,10 +64,116 @@ impl TryFrom<DirEntry> for File {
             let day: u32 = Self::capture_as_number(&caps, "day").unwrap();
 
             return Ok(Self {
-                file: direntry,
+                file: direntry.path(),
                 date: NaiveDate::from_ymd_opt(year, month, day).unwrap(),
             });
         };
         Err(FileError::ParseError("Could not parse file name"))
     }
 }
+
+fn try_get_date(file: &PathBuf) -> Result<NaiveDate, FileNameParseError> {
+    let file_name = file
+        .file_name()
+        .ok_or(FileNameParseError::TypeConversionError(
+            "Could not get filename from path: {:?}",
+        ))?
+        .to_str()
+        .ok_or(FileNameParseError::TypeConversionError(
+            "Could not get filename from path: {:?}",
+        ))?;
+
+    NaiveDate::parse_from_str(file_name, "%Y-%m-%d.md")
+        .or_else(|e| Err(FileNameParseError::ParseError(e)))
+}
+
+impl TryFrom<PathBuf> for File {
+    type Error = FileNameParseError;
+
+    fn try_from(path: PathBuf) -> Result<Self, Self::Error> {
+        Ok(Self {
+            date: try_get_date(&path)?,
+            file: path.into(),
+        })
+    }
+}
+impl File {
+    pub fn get_closest_files(files: Vec<PathBuf>, target: NaiveDate, n: usize) -> Vec<File> {
+        let mut dated_files = files
+            .into_iter()
+            .filter_map(|file| File::try_from(file).ok())
+            .collect::<Vec<_>>();
+        dated_files.sort_by_cached_key(|dated_file| (dated_file.date - target).num_days().abs());
+
+        let count = min(n, dated_files.len());
+        dated_files[..count].to_vec()
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use chrono::NaiveDate;
+    use std::path::PathBuf;
+
+    #[test]
+    fn test_get_closest_date() {
+        let files = vec![
+            PathBuf::from("./2024-01-01.md"),
+            PathBuf::from("./2024-01-02.md"),
+            PathBuf::from("./2024-01-03.md"),
+            PathBuf::from("./2024-02-01.md"),
+            PathBuf::from("./2024-03-01.md"),
+            PathBuf::from("./2024-04-01.md"),
+            PathBuf::from("./2024-04-02.md"),
+            PathBuf::from("./2024-04-03.md"),
+            PathBuf::from("./2024-04-04.md"),
+        ];
+
+        let res = File::get_closest_files(
+            files.clone(),
+            NaiveDate::from_ymd_opt(2023, 12, 30).unwrap(),
+            3,
+        );
+        let expected_res = vec![
+            File::try_from(PathBuf::from("./2024-01-01.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-01-02.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-01-03.md")).unwrap(),
+        ];
+        assert_eq!(res, expected_res);
+
+        let res = File::get_closest_files(
+            files.clone(),
+            NaiveDate::from_ymd_opt(2024, 2, 1).unwrap(),
+            3,
+        );
+        let expected_res = vec![
+            File::try_from(PathBuf::from("./2024-02-01.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-01-03.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-03-01.md")).unwrap(),
+        ];
+        assert_eq!(res, expected_res);
+
+        let res = File::get_closest_files(
+            files.clone(),
+            NaiveDate::from_ymd_opt(2024, 5, 2).unwrap(),
+            3,
+        );
+        let expected_res = vec![
+            File::try_from(PathBuf::from("./2024-04-04.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-04-03.md")).unwrap(),
+            File::try_from(PathBuf::from("./2024-04-02.md")).unwrap(),
+        ];
+        assert_eq!(res, expected_res);
+
+        let res = File::get_closest_files(
+            files[..1].to_vec(),
+            NaiveDate::from_ymd_opt(2023, 12, 30).unwrap(),
+            3,
+        );
+        let expected_res = vec![
+            File::try_from(PathBuf::from("./2024-01-01.md")).unwrap(),
+        ];
+        assert_eq!(res, expected_res);
+    }
+}

src/todo/mod.rs

@@ -3,3 +3,4 @@ mod tasks;
 
 pub use file::File;
 pub use tasks::{Status, TaskGroup};
+