Traits are closer to what actual calendars provide

src/traits.rs

@@ -10,7 +10,7 @@ use crate::item::VersionTag;
 use crate::calendar::CalendarId;
 
 #[async_trait]
-pub trait CalDavSource<T: PartialCalendar> {
+pub trait CalDavSource<T: BaseCalendar> {
     /// Returns the current calendars that this source contains
     /// This function may trigger an update (that can be a long process, or that can even fail, e.g. in case of a remote server)
     async fn get_calendars(&self) -> Result<HashMap<CalendarId, Arc<Mutex<T>>>, Box<dyn Error>>;
@@ -18,11 +18,9 @@ pub trait CalDavSource<T: PartialCalendar> {
     async fn get_calendar(&self, id: &CalendarId) -> Option<Arc<Mutex<T>>>;
 }
 
-/// A calendar we have a partial knowledge of.
-///
-/// Usually, this is a calendar from a remote source, that is synced to a CompleteCalendar
+/// This trait contains functions that are common to all calendars
 #[async_trait]
-pub trait PartialCalendar {
+pub trait BaseCalendar {
     /// Returns the calendar name
     fn name(&self) -> &str;
 
@@ -32,20 +30,11 @@ pub trait PartialCalendar {
     /// Returns the supported kinds of components for this calendar
     fn supported_components(&self) -> crate::calendar::SupportedComponents;
 
-    /// Get the IDs and the version tags of every item in this calendar
-    async fn get_item_version_tags(&self) -> Result<HashMap<ItemId, VersionTag>, Box<dyn Error>>;
-
-    /// Returns a particular item
-    async fn get_item_by_id_mut<'a>(&'a mut self, id: &ItemId) -> Option<&'a mut Item>;
-
-    /// Returns a particular item
-    async fn get_item_by_id<'a>(&'a self, id: &ItemId) -> Option<&'a Item>;
-
     /// Add an item into this calendar
     async fn add_item(&mut self, item: Item) -> Result<(), Box<dyn Error>>;
 
-    /// Remove an item from this calendar
-    async fn delete_item(&mut self, item_id: &ItemId) -> Result<(), Box<dyn Error>>;
+    /// Returns a particular item
+    async fn get_item_by_id<'a>(&'a self, id: &ItemId) -> Option<&'a Item>;
 
 
     /// Returns whether this calDAV calendar supports to-do items
@@ -57,6 +46,17 @@ pub trait PartialCalendar {
     fn supports_events(&self) -> bool {
         self.supported_components().contains(crate::calendar::SupportedComponents::EVENT)
     }
+}
+
+
+/// Functions availabe for calendars that are backed by a CalDAV server
+#[async_trait]
+pub trait DavCalendar : BaseCalendar {
+    /// Get the IDs and the version tags of every item in this calendar
+    async fn get_item_version_tags(&self) -> Result<HashMap<ItemId, VersionTag>, Box<dyn Error>>;
+
+    /// Delete an item
+    async fn delete_item(&mut self, item_id: &ItemId) -> Result<(), Box<dyn Error>>;
 
     /// Get the IDs of all current items in this calendar
     async fn get_item_ids(&self) -> Result<HashSet<ItemId>, Box<dyn Error>> {
@@ -65,20 +65,28 @@ pub trait PartialCalendar {
             .map(|(id, _tag)| id.clone())
             .collect())
     }
-
-    /// Finds the IDs of the items that are missing compared to a reference set
-    async fn find_deletions_from(&self, reference_set: HashSet<ItemId>) -> Result<HashSet<ItemId>, Box<dyn Error>> {
-        let current_items = self.get_item_ids().await?;
-        Ok(reference_set.difference(&current_items).map(|id| id.clone()).collect())
-    }
 }
 
-/// A calendar we always know everything about.
+
+/// Functions availabe for calendars we have full knowledge of
 ///
-/// Usually, this is a calendar fully stored on a local disk
+/// Usually, these are local calendars fully backed by a local folder
 #[async_trait]
-pub trait CompleteCalendar : PartialCalendar {
-    /// Returns the list of items that this calendar contains
-    async fn get_items(&self) -> Result<HashMap<ItemId, &Item>, Box<dyn Error>>;
-}
+pub trait CompleteCalendar : BaseCalendar {
+    /// Get the IDs of all current items in this calendar
+    async fn get_item_ids(&self) -> Result<HashSet<ItemId>, Box<dyn Error>>;
 
+    /// Returns all items that this calendar contains
+    async fn get_items(&self) -> Result<HashMap<ItemId, &Item>, Box<dyn Error>>;
+
+    /// Returns a particular item
+    async fn get_item_by_id_mut<'a>(&'a mut self, id: &ItemId) -> Option<&'a mut Item>;
+
+    /// Mark an item for deletion.
+    /// This is required so that the upcoming sync will know it should also also delete this task from the server
+    /// (and then call [`immediately_delete_item`] once it has been successfully deleted on the server)
+    async fn mark_for_deletion(&mut self, item_id: &ItemId) -> Result<(), Box<dyn Error>>;
+
+    /// Immediately remove an item. See [`mark_for_deletion`]
+    async fn immediately_delete_item(&mut self, item_id: &ItemId) -> Result<(), Box<dyn Error>>;
+}