#22 Add relative plot functionality for artists

src/display/date.rs

@@ -198,6 +198,14 @@ fn gather_songs_with_album_date(
     songs
 }
 
+/// Sums all plays in the given date frame
+pub fn sum_plays(entries: &[SongEntry], start: &DateTime<Tz>, end: &DateTime<Tz>) -> usize {
+    entries
+        .iter()
+        .filter(|entry| is_between(&entry.timestamp, start, end))
+        .count()
+}
+
 /// Checks if the given date is between (or equal) to the other two dates
 fn is_between(date: &DateTime<Tz>, start: &DateTime<Tz>, end: &DateTime<Tz>) -> bool {
     date.ge(start) && date.le(end)

src/plot.rs

@@ -9,10 +9,17 @@ use plotly::{Layout, Plot, Scatter};
 /// Responsible for plotting absolute plots
 pub mod absolute;
 
+/// Responsible for plotting plots relative to sum of plays
+pub mod relative;
+
 /// Creates a plot in a `plots/` folder
 ///
 /// Then opens it in the browser
-fn create_plot(dates: Vec<i64>, plays: Vec<usize>, title: &str) {
+fn create_plot<Y>(dates: Vec<i64>, plays: Vec<Y>, title: &str)
+where
+    Y: serde::Serialize + Clone + 'static,
+    // see https://github.com/igiagkiozis/plotly/blob/8903ff03ce9e8183624c40ccf7ddf863799cb92e/plotly/src/traces/scatter.rs#L292-L303
+{
     let mut plot = Plot::new();
     // TODO: make it display actual dates instead of UNIX timestamps xd
     plot.add_trace(Scatter::new(dates, plays).name(title));

src/plot/relative.rs

@@ -0,0 +1,26 @@
+use super::{create_plot, find_dates};
+use crate::display::date;
+use crate::types::{Artist, SongEntries};
+
+/// Creates a plot of the amount of plays of an [`Artist`] relative to all plays
+///
+/// Opens the plot in the browser
+pub fn artist(entries: &SongEntries, art: &Artist) {
+    let mut times = Vec::<i64>::new();
+    // percentages relative to the sum of all plays
+    let mut plays = Vec::<f64>::new();
+
+    let dates = find_dates(entries, art, true);
+
+    let start = dates.first().unwrap();
+    let sum_start = &entries.first_date();
+
+    for date in &dates {
+        times.push(date.timestamp());
+        let sum_of_plays = date::gather_artist(entries, art, start, date) as f64;
+        let sum_of_all_plays = date::sum_plays(entries, &sum_start, date) as f64;
+        plays.push(sum_of_plays / sum_of_all_plays);
+    }
+
+    create_plot(times, plays, format!("{art} - relative").as_str());
+}

src/types.rs

@@ -227,6 +227,14 @@ impl SongEntries {
         Ok(SongEntries(parse::parse(paths)?))
     }
 
+    /// Returns the date of the first (time-wise) occurrence of any [`SongEntry`]
+    pub fn first_date(&self) -> DateTime<Tz> {
+        self.iter()
+            .min_by(|x, y| x.timestamp.cmp(&y.timestamp))
+            .unwrap()
+            .timestamp
+    }
+
     /// Prints the top `num` of an `asp`
     ///
     /// * `asp` - [`Aspect::Songs`] (affected by [`display::SUM_ALBUMS`]) for top songs, [`Aspect::Albums`] for top albums and
@@ -289,6 +297,11 @@ impl SongEntries {
         plot::absolute::artist(self, art);
     }
 
+    /// Creates a plot of the artist relative to the total amount of plays
+    pub fn plot_artist_relative(&self, art: &Artist) {
+        plot::relative::artist(self, art);
+    }
+
     /// Adds search capability
     ///
     /// Use with methods from [`Find`]: [`.artist()`](Find::artist()), [`.album()`](Find::album()),

src/ui.rs

@@ -174,6 +174,7 @@ fn match_input(
         "print top albums" | "ptalbs" => match_print_top(entries, rl, &Aspect::Albums)?,
         "print top songs" | "ptsons" => match_print_top(entries, rl, &Aspect::Songs)?,
         "plot artist" | "gart" => match_plot_artist(entries, rl)?,
+        "plot artist relative" | "gartr" => match_plot_artist_relative(entries, rl)?,
         // when you press ENTER -> nothing happens, new prompt
         "" => (),
         _ => {
@@ -440,6 +441,20 @@ fn match_plot_artist(
     Ok(())
 }
 
+/// Used by [`match_input()`] for `plot artist relative` command
+fn match_plot_artist_relative(
+    entries: &SongEntries,
+    rl: &mut Editor<ShellHelper, FileHistory>,
+) -> Result<(), Box<dyn Error>> {
+    // 1st prompt: artist name
+    println!("Artist name?");
+    let usr_input_art = rl.readline(PROMPT_MAIN)?;
+    let art = entries.find().artist(&usr_input_art)?;
+
+    entries.plot_artist_relative(&art);
+    Ok(())
+}
+
 /// used by `*_date` functions in this module for when the user inputs a date
 ///
 /// # Arguments

src/ui/help.rs

@@ -195,12 +195,20 @@ fn print_top_commands<'a>() -> Vec<[&'a str; 3]> {
 
 /// Returns graph commands
 fn plot_commands<'a>() -> Vec<[&'a str; 3]> {
-    vec![[
-        "plot artist",
-        "gart",
-        "creates a plot of the absolute amount of plays of the given artist
+    vec![
+        [
+            "plot artist",
+            "gart",
+            "creates a plot of the absolute amount of plays of the given artist
         and opens it in the web browser",
-    ]]
+        ],
+        [
+            "plot artist relative",
+            "gartr",
+            "creates a plot of the amount of plays of the given artist
+        relative to all plays and opens it in the web browser",
+        ],
+    ]
 }
 
 #[cfg(test)]