use std::sync::Arc;

use async_graphql::{EmptyMutation, EmptySubscription, Schema};

use crate::service::GitService;

pub mod error;
pub mod query;
pub mod scalars;
pub mod types;

pub use error::to_gql;
pub use query::{GitSchema, Query, Repo};
pub use scalars::{Base64Scalar, DateTimeScalar, ObjectIdScalar};

/// Build a read-only graphql schema. The mutation and subscription
/// types are intentionally empty — gitdata exposes only query.
pub fn build_schema(state: export::AppState) -> GitSchema {
    Schema::build(Query, EmptyMutation, EmptySubscription)
        .data(Arc::new(GitService::new(state)))
        .finish()
}

#[cfg(test)]
mod tests {
    use super::*;

    fn schema_with_default_state() -> GitSchema {
        // The schema's SDL shape is independent of the embedded
        // `GitService` — data is only consulted at request time. Build a
        // schema without data; no requests are executed in these tests.
        Schema::build(Query, EmptyMutation, EmptySubscription).finish()
    }

    #[test]
    fn schema_contains_root_and_key_types() {
        let sdl = schema_with_default_state().sdl();
        // Print SDL for diagnostic if any assertion fails.
        eprintln!("--- SDL ---\n{sdl}\n---");
        assert!(sdl.contains("type Query"), "Query root missing");
        assert!(sdl.contains("repo("), "repo entry-point missing");
        assert!(sdl.contains("type Commit"), "Commit object missing");
        assert!(sdl.contains("type Blob"), "Blob object missing");
        assert!(sdl.contains("type Tree"), "Tree object missing");
        assert!(sdl.contains("type Tag"), "Tag object missing");
        assert!(sdl.contains("type Ref"), "Ref object missing");
        assert!(sdl.contains("type Blame"), "Blame object missing");
        assert!(sdl.contains("type Submodule"), "Submodule object missing");
        assert!(sdl.contains("type LanguageStat"), "LanguageStats missing");
        assert!(sdl.contains("type CommitStatus"), "CommitStatus missing");
        assert!(sdl.contains("scalar ObjectId"), "ObjectId scalar missing");
        assert!(sdl.contains("scalar DateTime"), "DateTime scalar missing");
        assert!(sdl.contains("union GitObject"), "GitObject union missing");
        assert!(sdl.contains("input PageInput"), "PageInput missing");
        assert!(
            sdl.contains("input LogOptionsInput"),
            "LogOptionsInput missing"
        );
        // read-only: schema should not declare user-facing Mutation fields
        assert!(!sdl.contains("type Mutation"), "Mutation should be empty");
    }
}