Vi-style editor and other editor improvements (#40)

* WIP VI wrapper for editor

* WIP: block cursor

* Create Edit trait, run CI on all feature options

* Add prints describing build steps to ci.sh

* Custom rendering for Vi editor

* Clippy fixes

* More clippy fixes

* Show clippy results in CI

* Fix for Redox

* Fix clippy lint

* Add vi feature to enable vi-style editor

* Add escape to libcosmic text box

src/font/system/redox.rs

@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: MIT OR Apache-2.0
+
+use alloc::{
+    string::{String, ToString},
+    sync::Arc,
+    vec::Vec,
+};
+
+use crate::{Attrs, Font, FontMatches};
+
+/// Access system fonts
+pub struct FontSystem{
+    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);
+
+        //TODO: allow loading fonts from memory
+        let mut db = fontdb::Database::new();
+        {
+            let now = std::time::Instant::now();
+
+            db.load_fonts_dir("/ui/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!(
+                "Parsed {} font faces in {}ms.",
+                db.len(),
+                now.elapsed().as_millis()
+            );
+        }
+
+        {
+            let now = std::time::Instant::now();
+
+            //TODO only do this on demand!
+            for i in 0..db.faces().len() {
+                let id = db.faces()[i].id;
+                unsafe { db.make_shared_face_data(id); }
+            }
+
+            log::info!(
+                "Mapped {} font faces in {}ms.",
+                db.len(),
+                now.elapsed().as_millis()
+            );
+        }
+
+        Self {
+            locale,
+            db,
+        }
+    }
+
+    pub fn locale(&self) -> &str {
+        &self.locale
+    }
+
+    pub fn db(&self) -> &fontdb::Database {
+        &self.db
+    }
+
+    // Clippy false positive
+    #[allow(clippy::needless_lifetimes)]
+    pub fn get_font<'a>(&'a self, id: fontdb::ID) -> Option<Arc<Font<'a>>> {
+        let face = self.db.face(id)?;
+        match Font::new(face) {
+            Some(font) => Some(Arc::new(font)),
+            None => {
+                log::warn!("failed to load font '{}'", face.post_script_name);
+                None
+            }
+        }
+    }
+
+    pub fn get_font_matches<'a>(&'a self, attrs: Attrs) -> Arc<FontMatches<'a>> {
+        let mut fonts = Vec::new();
+        for face in self.db.faces() {
+            if !attrs.matches(face) {
+                continue;
+            }
+
+            if let Some(font) = self.get_font(face.id) {
+                fonts.push(font);
+            }
+        }
+
+        Arc::new(FontMatches {
+            locale: &self.locale,
+            default_family: self.db.family_name(&attrs.family).to_string(),
+            fonts
+        })
+    }
+}