//! An _ordered_ variant of a [crate::qmdb::current] authenticated database optimized for fixed-size
//! values.
//!
//! This variant maintains the lexicographic-next active key for each active key, enabling exclusion
//! proofs (proving a key is currently inactive). Use [crate::qmdb::current::unordered::fixed] if
//! exclusion proofs are not needed.
//!
//! See [Db] for the main database type and [super::ExclusionProof] for proving key inactivity.

pub use super::db::KeyValueProof;
use crate::{
    index::ordered::Index,
    journal::contiguous::fixed::Journal,
    merkle::{Graftable, Location},
    qmdb::{
        any::{ordered::fixed::Operation, value::FixedEncoding, FixedValue},
        current::FixedConfig as Config,
        Error,
    },
    translator::Translator,
    Context,
};
use commonware_cryptography::Hasher;
use commonware_utils::Array;

pub type Db<F, E, K, V, H, T, const N: usize> = super::db::Db<
    F,
    E,
    Journal<E, Operation<F, K, V>>,
    K,
    FixedEncoding<V>,
    Index<T, Location<F>>,
    H,
    N,
>;

impl<
        F: Graftable,
        E: Context,
        K: Array,
        V: FixedValue,
        H: Hasher,
        T: Translator,
        const N: usize,
    > Db<F, E, K, V, H, T, N>
{
    /// Initializes a [Db] from the given `config`. Leverages parallel Merkleization to initialize
    /// the bitmap Merkle tree if a thread pool is provided.
    pub async fn init(context: E, config: Config<T>) -> Result<Self, Error<F>> {
        crate::qmdb::current::init(context, config).await
    }
}

pub mod partitioned {
    //! A variant of [super] that uses a partitioned index for the snapshot.

    use super::*;
    use crate::index::partitioned::ordered::Index;

    /// A partitioned variant of [super::Db].
    ///
    /// The const generic `P` specifies the number of prefix bytes used for partitioning:
    /// - `P = 1`: 256 partitions
    /// - `P = 2`: 65,536 partitions
    /// - `P = 3`: ~16 million partitions
    pub type Db<F, E, K, V, H, T, const P: usize, const N: usize> =
        crate::qmdb::current::ordered::db::Db<
            F,
            E,
            Journal<E, Operation<F, K, V>>,
            K,
            FixedEncoding<V>,
            Index<T, Location<F>, P>,
            H,
            N,
        >;

    impl<
            F: Graftable,
            E: Context,
            K: Array,
            V: FixedValue,
            H: Hasher,
            T: Translator,
            const P: usize,
            const N: usize,
        > Db<F, E, K, V, H, T, P, N>
    {
        /// Initializes a [Db] authenticated database from the given `config`. Leverages parallel
        /// Merkleization to initialize the bitmap Merkle tree if a thread pool is provided.
        pub async fn init(context: E, config: Config<T>) -> Result<Self, Error<F>> {
            crate::qmdb::current::init(context, config).await
        }
    }
}

#[cfg(test)]
pub mod test {
    use super::*;
    use crate::{
        mmr,
        qmdb::{
            current::{ordered::tests as shared, tests::fixed_config},
            Error,
        },
        translator::OneCap,
    };
    use commonware_cryptography::{sha256::Digest, Sha256};
    use commonware_macros::test_traced;
    use commonware_runtime::{deterministic, Metrics, Runner as _};
    use commonware_utils::{
        bitmap::{Prunable as BitMap, Readable as _},
        NZU64,
    };

    /// A type alias for the concrete [Db] type used in these unit tests.
    type CurrentTest = Db<mmr::Family, deterministic::Context, Digest, Digest, Sha256, OneCap, 32>;

    /// Return an [Db] database initialized with a fixed config.
    async fn open_db(context: deterministic::Context, partition_prefix: String) -> CurrentTest {
        let cfg = fixed_config::<OneCap>(&partition_prefix, &context);
        CurrentTest::init(context, cfg).await.unwrap()
    }

    #[test_traced("DEBUG")]
    pub fn test_current_db_verify_proof_over_bits_in_uncommitted_chunk() {
        shared::test_verify_proof_over_bits_in_uncommitted_chunk(open_db);
    }

    #[test_traced("DEBUG")]
    pub fn test_current_db_range_proofs() {
        shared::test_range_proofs(open_db);
    }

    /// Regression test: requesting a range proof for a location in a pruned bitmap chunk
    /// must return `Error::OperationPruned`, not panic in the bitmap accessor.
    #[test_traced("DEBUG")]
    pub fn test_range_proof_returns_error_on_pruned_chunks() {
        let executor = deterministic::Runner::default();
        executor.start(|context| async move {
            let partition = "range-proofs-pruned".to_string();
            let mut hasher = Sha256::new();
            let mut db = open_db(context.with_label("db"), partition).await;

            let chunk_bits = BitMap::<32>::CHUNK_SIZE_BITS;

            // Repeatedly update the same key to generate many inactive operations,
            // pushing the inactivity floor past at least one full bitmap chunk.
            let key = Sha256::fill(0x11);
            for i in 0..chunk_bits + 10 {
                let value = Sha256::hash(&i.to_be_bytes());
                let merkleized = db
                    .new_batch()
                    .write(key, Some(value))
                    .merkleize(&db, None)
                    .await
                    .unwrap();
                db.apply_batch(merkleized).await.unwrap();
            }

            // Prune the database
            let floor = db.any.inactivity_floor_loc;
            db.prune(floor).await.unwrap();

            assert!(
                db.status.pruned_chunks() > 0,
                "expected at least one pruned chunk"
            );

            // Requesting a range proof at location 0 (in the pruned range) should return
            // OperationPruned, not panic.
            let result = db
                .range_proof(&mut hasher, Location::new(0), NZU64!(1))
                .await;
            assert!(
                matches!(result, Err(Error::OperationPruned(_))),
                "expected OperationPruned, got {result:?}"
            );

            db.destroy().await.unwrap();
        });
    }

    #[test_traced("DEBUG")]
    pub fn test_current_db_key_value_proof() {
        shared::test_key_value_proof(open_db);
    }

    #[test_traced("WARN")]
    pub fn test_current_db_proving_repeated_updates() {
        shared::test_proving_repeated_updates(open_db);
    }

    #[test_traced("DEBUG")]
    pub fn test_current_db_exclusion_proofs() {
        shared::test_exclusion_proofs(open_db);
    }
}