feat(application): all use cases

crates/application/src/use_cases/thoughts.rs

@@ -0,0 +1,122 @@
+use domain::{
+    errors::DomainError,
+    events::DomainEvent,
+    models::thought::{Thought, Visibility},
+    ports::{EventPublisher, ThoughtRepository, UserRepository},
+    value_objects::{Content, ThoughtId, UserId},
+};
+
+pub struct CreateThoughtInput {
+    pub user_id: UserId,
+    pub content: String,
+    pub in_reply_to_id: Option<ThoughtId>,
+    pub visibility: Option<String>,
+    pub content_warning: Option<String>,
+    pub sensitive: bool,
+}
+pub struct CreateThoughtOutput { pub thought: Thought }
+
+pub async fn create_thought(
+    thoughts: &dyn ThoughtRepository,
+    _users: &dyn UserRepository,
+    events: &dyn EventPublisher,
+    input: CreateThoughtInput,
+) -> Result<CreateThoughtOutput, DomainError> {
+    let content = Content::new_local(input.content)?;
+    let visibility = input.visibility.as_deref().map(Visibility::from_str).unwrap_or(Visibility::Public);
+    let thought = Thought::new_local(
+        ThoughtId::new(), input.user_id,
+        content, input.in_reply_to_id.clone(),
+        visibility, input.content_warning, input.sensitive,
+    );
+    thoughts.save(&thought).await?;
+    events.publish(&DomainEvent::ThoughtCreated {
+        thought_id: thought.id.clone(),
+        user_id: thought.user_id.clone(),
+        in_reply_to_id: input.in_reply_to_id,
+    }).await?;
+    Ok(CreateThoughtOutput { thought })
+}
+
+pub async fn delete_thought(
+    thoughts: &dyn ThoughtRepository,
+    events: &dyn EventPublisher,
+    id: &ThoughtId,
+    user_id: &UserId,
+) -> Result<(), DomainError> {
+    let thought = thoughts.find_by_id(id).await?.ok_or(DomainError::NotFound)?;
+    if thought.user_id != *user_id { return Err(DomainError::NotFound); }
+    thoughts.delete(id, user_id).await?;
+    events.publish(&DomainEvent::ThoughtDeleted { thought_id: id.clone(), user_id: user_id.clone() }).await?;
+    Ok(())
+}
+
+pub async fn edit_thought(
+    thoughts: &dyn ThoughtRepository,
+    events: &dyn EventPublisher,
+    id: &ThoughtId,
+    user_id: &UserId,
+    new_content: String,
+) -> Result<(), DomainError> {
+    let thought = thoughts.find_by_id(id).await?.ok_or(DomainError::NotFound)?;
+    if thought.user_id != *user_id { return Err(DomainError::NotFound); }
+    let content = Content::new_local(new_content)?;
+    thoughts.update_content(id, &content).await?;
+    events.publish(&DomainEvent::ThoughtUpdated { thought_id: id.clone(), user_id: user_id.clone() }).await?;
+    Ok(())
+}
+
+pub async fn get_thought(thoughts: &dyn ThoughtRepository, id: &ThoughtId) -> Result<Thought, DomainError> {
+    thoughts.find_by_id(id).await?.ok_or(DomainError::NotFound)
+}
+
+pub async fn get_thread(thoughts: &dyn ThoughtRepository, id: &ThoughtId) -> Result<Vec<Thought>, DomainError> {
+    thoughts.get_thread(id).await
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use domain::{
+        models::user::User,
+        testing::{NoOpEventPublisher, TestStore},
+        value_objects::*,
+    };
+
+    fn user() -> User {
+        User::new_local(UserId::new(), Username::new("alice").unwrap(), Email::new("alice@ex.com").unwrap(), PasswordHash("h".into()))
+    }
+
+    fn input(uid: UserId) -> CreateThoughtInput {
+        CreateThoughtInput { user_id: uid, content: "hello".into(), in_reply_to_id: None, visibility: None, content_warning: None, sensitive: false }
+    }
+
+    #[tokio::test]
+    async fn create_thought_saves_and_emits_event() {
+        let store = TestStore::default();
+        let u = user(); store.users.lock().unwrap().push(u.clone());
+        let out = create_thought(&store, &store, &store, input(u.id.clone())).await.unwrap();
+        assert_eq!(out.thought.content.as_str(), "hello");
+        assert_eq!(store.events.lock().unwrap().len(), 1);
+    }
+
+    #[tokio::test]
+    async fn delete_own_thought_succeeds() {
+        let store = TestStore::default();
+        let u = user(); store.users.lock().unwrap().push(u.clone());
+        let out = create_thought(&store, &store, &NoOpEventPublisher, input(u.id.clone())).await.unwrap();
+        delete_thought(&store, &NoOpEventPublisher, &out.thought.id, &u.id).await.unwrap();
+        assert!(store.thoughts.lock().unwrap().is_empty());
+    }
+
+    #[tokio::test]
+    async fn delete_other_thought_returns_not_found() {
+        let store = TestStore::default();
+        let alice = user();
+        let bob = User::new_local(UserId::new(), Username::new("bob").unwrap(), Email::new("bob@ex.com").unwrap(), PasswordHash("h".into()));
+        store.users.lock().unwrap().extend([alice.clone(), bob.clone()]);
+        let out = create_thought(&store, &store, &NoOpEventPublisher, input(alice.id.clone())).await.unwrap();
+        let err = delete_thought(&store, &NoOpEventPublisher, &out.thought.id, &bob.id).await.unwrap_err();
+        assert!(matches!(err, DomainError::NotFound));
+    }
+}