application layer

Co-authored-by: Copilot <copilot@github.com>

crates/application/src/use_cases/log_review.rs

@@ -0,0 +1,115 @@
+use domain::{
+    errors::DomainError,
+    events::DomainEvent,
+    models::{Movie, Review},
+    value_objects::{Comment, ExternalMetadataId, MovieTitle, Rating, ReleaseYear, UserId},
+};
+
+use crate::{commands::LogReviewCommand, context::AppContext};
+
+pub async fn execute(ctx: &AppContext, cmd: LogReviewCommand) -> Result<(), DomainError> {
+    let rating = Rating::new(cmd.rating)?;
+    let user_id = UserId::from_uuid(cmd.user_id);
+    let comment = cmd.comment.clone().map(Comment::new).transpose()?;
+
+    let (movie, is_new_movie) = resolve_movie(ctx, &cmd).await?;
+
+    ctx.repository.upsert_movie(&movie).await?;
+
+    let review = Review::new(movie.id().clone(), user_id, rating, comment, cmd.watched_at)?;
+    let review_event = ctx.repository.save_review(&review).await?;
+
+    publish_events(ctx, &movie, is_new_movie, review_event).await?;
+
+    Ok(())
+}
+
+async fn resolve_movie(
+    ctx: &AppContext,
+    cmd: &LogReviewCommand,
+) -> Result<(Movie, bool), DomainError> {
+    if let Some(ext_id_str) = &cmd.external_metadata_id {
+        if let Some(resolved) = resolve_external_movie(ctx, ext_id_str).await? {
+            return Ok(resolved);
+        }
+    }
+
+    resolve_manual_movie(ctx, cmd).await
+}
+
+async fn resolve_external_movie(
+    ctx: &AppContext,
+    ext_id_str: &str,
+) -> Result<Option<(Movie, bool)>, DomainError> {
+    let tmdb_id = ExternalMetadataId::new(ext_id_str.to_string())?;
+
+    if let Some(m) = ctx.repository.get_movie_by_external_id(&tmdb_id).await? {
+        return Ok(Some((m, false)));
+    }
+
+    match ctx.metadata_client.fetch_movie_metadata(&tmdb_id).await {
+        Ok(m) => Ok(Some((m, true))),
+        Err(e) => {
+            tracing::warn!(
+                "Failed to fetch from TMDB, falling back to manual entry: {:?}",
+                e
+            );
+            Ok(None)
+        }
+    }
+}
+
+async fn resolve_manual_movie(
+    ctx: &AppContext,
+    cmd: &LogReviewCommand,
+) -> Result<(Movie, bool), DomainError> {
+    let title_str = cmd.manual_title.as_ref().ok_or_else(|| {
+        DomainError::ValidationError(
+            "Manual title required if TMDB fetch fails or is omitted".into(),
+        )
+    })?;
+    let year_val = cmd.manual_release_year.ok_or_else(|| {
+        DomainError::ValidationError(
+            "Manual release year required if TMDB fetch fails or is omitted".into(),
+        )
+    })?;
+
+    let title = MovieTitle::new(title_str.clone())?;
+    let release_year = ReleaseYear::new(year_val)?;
+
+    let candidates = ctx
+        .repository
+        .get_movies_by_title_and_year(&title, &release_year)
+        .await?;
+
+    let matched_movie = candidates
+        .into_iter()
+        .find(|m| m.is_manual_match(&title, &release_year, cmd.manual_director.as_deref()));
+
+    if let Some(existing_movie) = matched_movie {
+        Ok((existing_movie, false))
+    } else {
+        let new_movie = Movie::new(None, title, release_year, cmd.manual_director.clone(), None);
+        Ok((new_movie, true))
+    }
+}
+
+async fn publish_events(
+    ctx: &AppContext,
+    movie: &Movie,
+    is_new_movie: bool,
+    review_event: DomainEvent,
+) -> Result<(), DomainError> {
+    if is_new_movie {
+        if let Some(ext_id) = movie.external_metadata_id() {
+            let discovery_event = DomainEvent::MovieDiscovered {
+                movie_id: movie.id().clone(),
+                external_metadata_id: ext_id.clone(),
+            };
+            ctx.event_publisher.publish(&discovery_event).await?;
+        }
+    }
+
+    ctx.event_publisher.publish(&review_event).await?;
+    Ok(())
+}