reduce IO operations

store the Handle on the project itself
instead of re-reading the file each time

src/application.rs

@@ -11,7 +11,7 @@ use crate::config;
 use crate::widgets::Window;
 
 pub enum Action {
-    OpenProject(Project),
+    OpenProject(Rc<Project>),
     NewProject(gio::File),
 }
 

src/common.rs

@@ -38,11 +38,8 @@ pub fn create_tmp(filename: &str) -> anyhow::Result<PathBuf> {
     Ok(temp_path)
 }
 
-pub fn render(file: &gio::File, output_size: f64, dest: Option<PathBuf>) -> anyhow::Result<(gio::File, cairo::SvgSurface)> {
-    let stream = file.read(gio::NONE_CANCELLABLE)?.upcast::<gio::InputStream>();
-    let handle = Handle::from_stream(&LoadOptions::new(None), &stream, gio::NONE_CANCELLABLE)?;
-
-    let dest = dest.unwrap_or(create_tmp(&format!("#hicolor-{}-{}", output_size, file.get_basename().unwrap().to_str().unwrap()))?);
+pub fn render(handle: &Handle, basename: &str, output_size: f64, dest: Option<PathBuf>) -> anyhow::Result<(gio::File, cairo::SvgSurface)> {
+    let dest = dest.unwrap_or(create_tmp(&format!("#hicolor-{}-{}", output_size, basename))?);
 
     let mut surface = cairo::SvgSurface::new(output_size, output_size, Some(dest.clone())).unwrap();
     surface.set_document_unit(cairo::SvgUnit::Px);
@@ -64,13 +61,9 @@ pub fn render(file: &gio::File, output_size: f64, dest: Option<PathBuf>) -> anyh
     Ok((gio::File::new_for_path(dest), surface))
 }
 
-pub fn render_by_id(file: &gio::File, id: &str, output_size: f64, dest: Option<PathBuf>) -> anyhow::Result<(gio::File, cairo::SvgSurface)> {
-    let stream = file.read(gio::NONE_CANCELLABLE)?.upcast::<gio::InputStream>();
-    let mut handle = Handle::from_stream(&LoadOptions::new(None), &stream, gio::NONE_CANCELLABLE)?;
-
-    let dest = dest.unwrap_or(create_tmp(&format!("{}-{}-{}", id, output_size, file.get_basename().unwrap().to_str().unwrap()))?);
+pub fn render_by_id(handle: &Handle, basename: &str, id: &str, output_size: f64, dest: Option<PathBuf>) -> anyhow::Result<(gio::File, cairo::SvgSurface)> {
+    let dest = dest.unwrap_or(create_tmp(&format!("{}-{}-{}", id, output_size, basename))?);
 
-    handle.set_stylesheet("#layer3,#layer2 {visibility: hidden}")?;
     if handle.has_sub(id)? {
         let viewport = {
             let doc = handle.get_dimensions(Dpi::default(), &SizeCallback::default(), false)?;

src/project.rs

 use super::common;
-use anyhow::anyhow;
 use gettextrs::gettext;
 use gio::prelude::FileExt;
 use gtk::prelude::*;
-use librsvg::{CairoRenderer, Loader};
+use rsvg_internals::{Dpi, Handle, LoadOptions, SizeCallback};
+use std::rc::Rc;
 
 #[derive(PartialEq, Debug, Clone)]
 pub enum ProjectType {
@@ -11,14 +11,14 @@ pub enum ProjectType {
     Preview, // A 128px SVG found
 }
 
-#[derive(Debug, Clone)]
 pub struct Project {
     pub file: gio::File,
     pub project_type: ProjectType,
+    handle: Handle,
 }
 
 impl Project {
-    pub fn from_template(dest: gio::File) -> anyhow::Result<Self> {
+    pub fn from_template(dest: gio::File) -> anyhow::Result<Rc<Self>> {
         let template = gio::File::new_for_uri("resource://org/gnome/design/AppIconPreview/templates/empty_project.svg");
         // Creates the parent directory tree if it does not already exist
         dest.get_parent().map(|parent| parent.make_directory_with_parents(gio::NONE_CANCELLABLE));
@@ -27,27 +27,30 @@ impl Project {
         Project::parse(dest)
     }
 
-    pub fn parse(file: gio::File) -> anyhow::Result<Self> {
-        let path = file.get_path().ok_or_else(|| anyhow!("Failed to get the path"))?;
+    pub fn parse(file: gio::File) -> anyhow::Result<Rc<Self>> {
+        let stream = file.read(gio::NONE_CANCELLABLE)?.upcast::<gio::InputStream>();
+        let mut handle = Handle::from_stream(&LoadOptions::new(None), &stream, gio::NONE_CANCELLABLE)?;
+        handle.set_stylesheet("#layer3,#layer2 {visibility: hidden}")?;
 
-        let handle = Loader::new().read_path(&path)?;
-        let renderer = CairoRenderer::new(&handle);
-        let dimensions = renderer.intrinsic_dimensions();
-        let width = dimensions.width.unwrap().length;
-        let height = dimensions.height.unwrap().length;
+        let dimensions = handle.get_dimensions(Dpi::default(), &SizeCallback::default(), false)?;
+
+        let width = dimensions.width as f64;
+        let height = dimensions.height as f64;
 
         if (width - 128.0).abs() < std::f64::EPSILON && (height - 128.0).abs() < std::f64::EPSILON {
-            return Ok(Self {
+            return Ok(Rc::new(Self {
                 project_type: ProjectType::Preview,
                 file,
-            });
+                handle,
+            }));
         }
 
-        if handle.has_element_with_id("#hicolor")? && handle.has_element_with_id("#symbolic")? {
-            return Ok(Self {
+        if handle.has_sub("#hicolor")? && handle.has_sub("#symbolic")? {
+            return Ok(Rc::new(Self {
                 file,
                 project_type: ProjectType::Icon,
-            });
+                handle,
+            }));
         }
         anyhow::bail!("not found")
     }
@@ -128,8 +131,8 @@ impl Project {
 
     pub fn get_hicolor(&self, dest: Option<std::path::PathBuf>) -> anyhow::Result<(gio::File, cairo::SvgSurface)> {
         match self.project_type {
-            ProjectType::Icon => common::render_by_id(&self.file, "#hicolor", 128.0, dest),
-            ProjectType::Preview => common::render(&self.file, 128.0, dest),
+            ProjectType::Icon => common::render_by_id(&self.handle, &self.name(), "#hicolor", 128.0, dest),
+            ProjectType::Preview => common::render(&self.handle, &self.name(), 128.0, dest),
         }
     }
 
@@ -137,7 +140,7 @@ impl Project {
         match self.project_type {
             ProjectType::Icon => {
                 let dest = common::create_tmp(&format!("#symblic-16-{}-symbolic.svg", self.name()))?;
-                common::render_by_id(&self.file, "#symbolic", 16.0, Some(dest))
+                common::render_by_id(&self.handle, &self.name(), "#symbolic", 16.0, Some(dest))
             }
             ProjectType::Preview => anyhow::bail!("No symbolic support for Preview icons"),
         }

src/widgets/recents/item.rs

 use gtk::prelude::*;
 
 use crate::project::Project;
+use std::rc::Rc;
 
 #[derive(Clone, Serialize, Deserialize)]
 pub struct RecentItem {
@@ -10,11 +11,11 @@ pub struct RecentItem {
 pub struct RecentItemRow {
     pub widget: gtk::FlowBoxChild,
     pub event_box: gtk::EventBox,
-    project: Project,
+    project: Rc<Project>,
 }
 
 impl RecentItemRow {
-    pub fn new(project: Project) -> Self {
+    pub fn new(project: Rc<Project>) -> Self {
         let widget = gtk::FlowBoxChild::new();
         let event_box = gtk::EventBox::new();
 

src/widgets/window.rs

@@ -21,7 +21,7 @@ pub struct Window {
     builder: gtk::Builder,
     sender: glib::Sender<Action>,
     previewer: ProjectPreviewer,
-    open_project: Rc<RefCell<Option<Project>>>,
+    open_project: RefCell<Option<Rc<Project>>>,
     exporter: ExportPopover,
     monitor: RefCell<Option<gio::FileMonitor>>,
 }
@@ -38,7 +38,7 @@ impl Window {
             sender,
             previewer,
             exporter: ExportPopover::new(),
-            open_project: Rc::new(RefCell::new(None)),
+            open_project: RefCell::new(None),
             monitor: RefCell::new(None),
         });
 
@@ -49,7 +49,7 @@ impl Window {
         window_widget
     }
 
-    pub fn set_open_project(&self, project: Project) {
+    pub fn set_open_project(&self, project: Rc<Project>) {
         self.set_view(View::Previewer);
         self.previewer.preview(&project);
         self.exporter.set_project(&project);