mango: show focused window next to tags, fix mmsg lookup, 0.15.x compat

- new focused-window block ({icon} {app_id} - {title}) driven by the
  active_client field of mmsg watch all-monitors (mangowm >= 0.14)
- resolve program icons via freedesktop icon themes/.desktop files
  (new icon module, cairo png feature, cached per app_id)
- new show_focused_window config option (default true)
- run mmsg from PATH instead of hardcoded /usr/bin/mmsg (broken on NixOS)
- handle null active_client fields (no focused client) without failing
  to parse the whole event
- drop stale TODO comment and unused variable in mango provider
- add .justfile run recipe exporting MANGO_INSTANCE_SIGNATURE

1 files changed, 63 insertions, 1 deletions

diff --git a/src/bar.rs b/src/bar.rs
index 237c46a..102978d 100644
--- a/src/bar.rs
+++ b/src/bar.rs
@@ -14,7 +14,7 @@ use crate::protocol::*;
 use crate::shared_state::SharedState;
 use crate::state::State;
 use crate::text::{self, ComputedText, RenderOptions};
-use crate::wm_info_provider::Tag;
+use crate::wm_info_provider::{FocusedWindow, Tag};
 
 pub struct Bar {
     pub output: Output,
@@ -33,10 +33,12 @@ pub struct Bar {
     tags: Vec<Tag>,
     layout_name: Option<String>,
     mode_name: Option<String>,
+    focused_window: Option<FocusedWindow>,
     tags_btns: ButtonManager<u32>,
     tags_computed: Vec<(u32, ColorPair, ComputedText)>,
     layout_name_computed: Option<ComputedText>,
     mode_computed: Option<ComputedText>,
+    focused_window_computed: Option<ComputedText>,
 }
 
 #[derive(Debug, PartialEq)]
@@ -79,10 +81,12 @@ impl Bar {
             tags: Vec::new(),
             layout_name: None,
             mode_name: None,
+            focused_window: None,
             tags_btns: Default::default(),
             tags_computed: Vec::new(),
             layout_name_computed: None,
             mode_computed: None,
+            focused_window_computed: None,
         }
     }
 
@@ -112,6 +116,11 @@ impl Bar {
         self.mode_computed = None;
     }
 
+    pub fn set_focused_window(&mut self, focused_window: Option<FocusedWindow>) {
+        self.focused_window = focused_window;
+        self.focused_window_computed = None;
+    }
+
     pub fn click(
         &mut self,
         conn: &mut Connection<State>,
@@ -287,6 +296,59 @@ impl Bar {
             }
         }
 
+        // Display focused window
+        if ss.config.show_focused_window
+            && let Some(focused_window) = &self.focused_window
+        {
+            if let Some(icon) = ss.icon_cache.get(&focused_window.app_id, self.height) {
+                let icon_size = height_f - 4.0;
+                let scale = icon_size / (icon.width() as f64).max(icon.height() as f64);
+                let icon_w = icon.width() as f64 * scale;
+                let icon_h = icon.height() as f64 * scale;
+                cairo_ctx.save().unwrap();
+                cairo_ctx.translate(
+                    offset_left + (icon_size - icon_w) / 2.0,
+                    (height_f - icon_h) / 2.0,
+                );
+                cairo_ctx.scale(scale, scale);
+                cairo_ctx.set_source_surface(icon, 0.0, 0.0).unwrap();
+                cairo_ctx.paint().unwrap();
+                cairo_ctx.restore().unwrap();
+                offset_left += icon_size + 5.0;
+            }
+            let text = self.focused_window_computed.get_or_insert_with(|| {
+                let label = if focused_window.title.is_empty() {
+                    focused_window.app_id.clone()
+                } else {
+                    format!("{} - {}", focused_window.app_id, focused_window.title)
+                };
+                ComputedText::new(
+                    &label,
+                    text::Attributes {
+                        font: &ss.config.font,
+                        padding_left: 10.0,
+                        padding_right: 10.0,
+                        min_width: None,
+                        align: Default::default(),
+                        markup: false,
+                    },
+                )
+            });
+            text.render(
+                &cairo_ctx,
+                RenderOptions {
+                    x_offset: offset_left,
+                    bar_height: height_f,
+                    fg_color: ss.config.tag_inactive_fg,
+                    bg_color: None,
+                    r_left: 0.0,
+                    r_right: 0.0,
+                    overlap: 0.0,
+                },
+            );
+            offset_left += text.width;
+        }
+
         // Display mode
         if ss.config.show_mode {
             if let Some(mode) = &self.mode_name {