movies-diary/crates/application/src/use_cases/delete_review.rs

use crate::{commands::DeleteReviewCommand, context::AppContext};
use domain::{
    errors::DomainError,
    events::DomainEvent,
    value_objects::{ReviewId, UserId},
};

pub async fn execute(ctx: &AppContext, cmd: DeleteReviewCommand) -> Result<(), DomainError> {
    let review_id = ReviewId::from_uuid(cmd.review_id);
    let requesting_user_id = UserId::from_uuid(cmd.requesting_user_id);

    let review = ctx
        .review_repository
        .get_review_by_id(&review_id)
        .await?
        .ok_or_else(|| DomainError::NotFound(format!("review {}", cmd.review_id)))?;

    if review.user_id() != &requesting_user_id {
        return Err(DomainError::Unauthorized("not your review".into()));
    }

    let movie_id = review.movie_id().clone();
    ctx.review_repository.delete_review(&review_id).await?;

    if let Err(e) = ctx
        .event_publisher
        .publish(&DomainEvent::ReviewDeleted {
            review_id: review_id.clone(),
            user_id: requesting_user_id.clone(),
        })
        .await
    {
        tracing::warn!("failed to publish ReviewDeleted: {e}");
    }

    let history = ctx.diary_repository.get_review_history(&movie_id).await?;
    if history.viewings().is_empty() {
        let poster_path = history.movie().poster_path().cloned();
        ctx.movie_repository.delete_movie(&movie_id).await?;
        // best-effort: movie is already deleted, so publish failure is non-fatal
        if let Err(e) = ctx
            .event_publisher
            .publish(&DomainEvent::MovieDeleted {
                movie_id,
                poster_path,
            })
            .await
        {
            tracing::warn!("failed to publish MovieDeleted event: {e}");
        }
    }

    Ok(())
}

#[cfg(test)]
mod tests {
    use std::sync::Arc;

    use chrono::Utc;

    use domain::{
        models::{Movie, Review},
        ports::{MovieRepository, ReviewRepository},
        testing::{
            FakeDiaryRepository, InMemoryMovieRepository, InMemoryReviewRepository,
            NoopEventPublisher,
        },
        value_objects::{MovieId, MovieTitle, Rating, ReleaseYear, UserId},
    };

    use crate::{
        commands::DeleteReviewCommand, test_helpers::TestContextBuilder, use_cases::delete_review,
    };

    fn make_movie() -> Movie {
        Movie::new(
            None,
            MovieTitle::new("Terminator".into()).unwrap(),
            ReleaseYear::new(1984).unwrap(),
            None,
            None,
        )
    }

    fn make_review(movie_id: MovieId, user_id: UserId) -> Review {
        Review::new(
            movie_id,
            user_id,
            Rating::new(4).unwrap(),
            None,
            Utc::now().naive_utc(),
        )
        .unwrap()
    }

    #[tokio::test]
    async fn test_delete_review_removes_it() {
        let movies = InMemoryMovieRepository::new();
        let reviews = InMemoryReviewRepository::new();
        let diary = FakeDiaryRepository::new();
        let events = NoopEventPublisher::new();

        let movie = make_movie();
        let user_id = UserId::from_uuid(uuid::Uuid::new_v4());
        let review = make_review(movie.id().clone(), user_id.clone());

        movies.upsert_movie(&movie).await.unwrap();
        reviews.save_review(&review).await.unwrap();
        diary.seed_history(movie.clone(), vec![]);

        let ctx = TestContextBuilder::new()
            .with_movies(Arc::clone(&movies) as _)
            .with_reviews(Arc::clone(&reviews) as _)
            .with_diary(Arc::clone(&diary) as _)
            .with_event_publisher(Arc::clone(&events) as _)
            .build();

        delete_review::execute(
            &ctx,
            DeleteReviewCommand {
                review_id: review.id().value(),
                requesting_user_id: user_id.value(),
            },
        )
        .await
        .unwrap();

        assert_eq!(reviews.count(), 0, "review should be deleted");
        assert!(
            movies.get_movie_by_id(movie.id()).await.unwrap().is_none(),
            "movie should be deleted when no reviews remain"
        );
    }

    #[tokio::test]
    async fn test_delete_review_wrong_user_is_unauthorized() {
        let reviews = InMemoryReviewRepository::new();

        let movie_id = MovieId::from_uuid(uuid::Uuid::new_v4());
        let owner_id = UserId::from_uuid(uuid::Uuid::new_v4());
        let other_id = uuid::Uuid::new_v4();
        let review = make_review(movie_id, owner_id);

        reviews.save_review(&review).await.unwrap();

        let ctx = TestContextBuilder::new()
            .with_reviews(Arc::clone(&reviews) as _)
            .build();

        let result = delete_review::execute(
            &ctx,
            DeleteReviewCommand {
                review_id: review.id().value(),
                requesting_user_id: other_id,
            },
        )
        .await;

        assert!(result.is_err(), "wrong user should not be able to delete");
        assert_eq!(reviews.count(), 1, "review should still exist");
    }
}