rework multibar

src/multibar.rs

@@ -1,37 +1,92 @@
 use std::fmt;
 
+#[derive(Debug, Clone, Copy)]
+pub enum BarSegment<'s> {
+    Dynamic(&'s str, u64),
+    Static(&'s str),
+}
+
+impl<'s> BarSegment<'s> {
+    fn char(&self) -> &'s str {
+        match self {
+            BarSegment::Dynamic(c, _) => c,
+            BarSegment::Static(c) => c,
+        }
+    }
+
+    fn length(&self) -> u64 {
+        match self {
+            BarSegment::Dynamic(c, len) => *len,
+            BarSegment::Static(c) => c.len() as u64,
+        }
+    }
+
+    fn is_static(&self) -> bool {
+        matches!(self, BarSegment::Static(_))
+    }
+
+    fn scaled(&self, new_len: u64) -> Self {
+        match self {
+            BarSegment::Dynamic(c, _) => BarSegment::Dynamic(c, new_len),
+            BarSegment::Static(c) => BarSegment::Static(c),
+        }
+    }
+}
+
 #[derive(Debug)]
-pub struct MultiBar<'s, const N: usize>(pub [(&'s str, u64, bool); N]);
+pub struct MultiBar<'s, const N: usize>(pub [BarSegment<'s>; N]);
 
 impl<const N: usize> MultiBar<'_, N> {
-    /// Total length of the bar
-    pub(crate) fn length(&self) -> u64 {
-        self.0.iter().map(|(_, len, _)| *len).sum::<u64>()
+    fn dynamic_length(&self) -> u64 {
+        self.0
+            .iter()
+            .filter(|seg| !seg.is_static())
+            .map(|seg| seg.length())
+            .sum::<u64>()
+    }
+
+    fn static_length(&self) -> u64 {
+        self.0
+            .iter()
+            .filter(|seg| seg.is_static())
+            .map(|seg| seg.length())
+            .sum::<u64>()
     }
 
     /// Transforms the bar to be of target size
+    /// Static parts remain the same length, dynamic parts are scaled proportionally
     pub(crate) fn scale(&self, size: u64) -> Self {
-        let length = std::cmp::max(self.length(), 1);
+        let static_len = self.static_length();
+        let dynamic_len = std::cmp::max(self.dynamic_length(), 1);
+
+        let available_size = size.saturating_sub(static_len);
+
         let mut prev_prop = 0;
         let mut curr_prop = 0;
 
-        let inner = self.0.map(|(c, len, const_len)| {
-            if const_len {
-                return (c, len, const_len);
+        let inner = self.0.map(|seg| match seg {
+            BarSegment::Static(_) => seg,
+            BarSegment::Dynamic(c, len) => {
+                curr_prop += len;
+                let nb_chars = available_size * curr_prop / dynamic_len
+                    - available_size * prev_prop / dynamic_len;
+                prev_prop = curr_prop;
+                BarSegment::Dynamic(c, nb_chars)
             }
-            curr_prop += len;
-            let nb_chars = size * curr_prop / length - size * prev_prop / length;
-
-            prev_prop = curr_prop;
-            (c, nb_chars, const_len)
         });
+
         Self(inner)
     }
 }
 
 impl<const N: usize> fmt::Display for MultiBar<'_, N> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        for &(c, len, _) in &self.0 {
+        for seg in &self.0 {
+            let (c, len) = match seg {
+                BarSegment::Dynamic(c, len) => (c, *len),
+                BarSegment::Static(c) => (c, c.len() as u64),
+            };
+
             for _ in 0..len {
                 f.write_str(c)?;
             }