refactor: better separate user app and system app logic

src/apps/system.rs

@@ -1,7 +1,7 @@
 use crate::{
     apps::DesktopList,
     common::{DesktopEntry, DesktopHandler, Handleable},
-    error::Result,
+    error::{Error, Result},
 };
 use mime::Mime;
 use std::{collections::BTreeMap, convert::TryFrom, ffi::OsString};
@@ -16,13 +16,21 @@ pub struct SystemApps {
 
 impl SystemApps {
     /// Get the list of handlers associated with a given mime
-    pub fn get_handlers(&self, mime: &Mime) -> Option<DesktopList> {
-        Some(self.associations.get(mime)?.clone())
+    pub fn get_handlers(&self, mime: &Mime) -> Result<DesktopList> {
+        Ok(self
+            .associations
+            .get(mime)
+            .ok_or_else(|| Error::NotFound(mime.to_string()))?
+            .clone())
     }
 
     /// Get the primary of handler associated with a given mime
-    pub fn get_handler(&self, mime: &Mime) -> Option<DesktopHandler> {
-        Some(self.get_handlers(mime)?.front()?.clone())
+    pub fn get_handler(&self, mime: &Mime) -> Result<DesktopHandler> {
+        Ok(self
+            .get_handlers(mime)?
+            .front()
+            .ok_or_else(|| Error::NotFound(mime.to_string()))?
+            .clone())
     }
 
     /// Get all system-level desktop entries on the system

src/config/main_config.rs

@@ -57,7 +57,9 @@ impl Config {
     pub fn get_handler(&self, mime: &Mime) -> Result<DesktopHandler> {
         match self.mime_apps.get_handler_from_user(mime, &self.config) {
             Err(e) if matches!(e, Error::Cancelled) => Err(e),
-            h => h.or_else(|_| self.get_handler_from_added_associations(mime)),
+            h => h
+                .or_else(|_| self.get_handler_from_added_associations(mime))
+                .or_else(|_| self.system_apps.get_handler(mime)),
         }
     }
 
@@ -70,10 +72,7 @@ impl Config {
         self.mime_apps
             .added_associations
             .get(mime)
-            .map_or_else(
-                || self.system_apps.get_handler(mime),
-                |h| h.front().cloned(),
-            )
+            .and_then(|h| h.front().cloned())
             .ok_or_else(|| Error::NotFound(mime.to_string()))
     }