Text library moved from libcosmic

src/font/system.rs

@@ -0,0 +1,83 @@
+use std::ops::Deref;
+
+use super::{Font, FontMatches};
+
+pub struct FontSystem {
+    pub locale: String,
+    db: fontdb::Database,
+}
+
+impl FontSystem {
+    pub fn new() -> Self {
+        let locale = sys_locale::get_locale().unwrap_or_else(|| {
+            log::warn!("failed to get system locale, falling back to en-US");
+            String::from("en-US")
+        });
+        log::info!("Locale: {}", locale);
+
+        let mut db = fontdb::Database::new();
+        let now = std::time::Instant::now();
+        db.load_system_fonts();
+        //TODO: configurable default fonts
+        db.set_monospace_family("Fira Mono");
+        db.set_sans_serif_family("Fira Sans");
+        db.set_serif_family("DejaVu Serif");
+        log::info!(
+            "Loaded {} font faces in {}ms.",
+            db.len(),
+            now.elapsed().as_millis()
+        );
+
+        //TODO only do this on demand!
+        assert_eq!(db.len(), db.faces().len());
+        for i in 0..db.len() {
+            let id = db.faces()[i].id;
+            unsafe {
+                db.make_shared_face_data(id);
+            }
+        }
+
+        Self { locale, db }
+    }
+
+    pub fn matches<'a, F: Fn(&fontdb::FaceInfo) -> bool>(
+        &'a self,
+        f: F,
+    ) -> Option<FontMatches<'a>> {
+        let mut fonts = Vec::new();
+        for face in self.db.faces() {
+            if !f(face) {
+                continue;
+            }
+
+            let font_opt = Font::new(
+                face,
+                match &face.source {
+                    fontdb::Source::Binary(data) => data.deref().as_ref(),
+                    fontdb::Source::File(path) => {
+                        log::warn!("Unsupported fontdb Source::File('{}')", path.display());
+                        continue;
+                    }
+                    fontdb::Source::SharedFile(_path, data) => data.deref().as_ref(),
+                },
+                face.index,
+            );
+
+            match font_opt {
+                Some(font) => fonts.push(font),
+                None => {
+                    log::warn!("failed to load font '{}'", face.post_script_name);
+                }
+            }
+        }
+
+        if !fonts.is_empty() {
+            Some(FontMatches {
+                locale: &self.locale,
+                fonts
+            })
+        } else {
+            None
+        }
+    }
+}