// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at https://mozilla.org/MPL/2.0/.

//! Git-LFS object bookkeeping: which content-addressed objects (by sha256 oid)
//! each repository has stored. The bytes themselves live on disk under
//! `storage.lfs_dir`; this table answers "does this repo have this object?" for
//! the batch API and access control.

use sqlx::Row;

use crate::{Store, StoreError, new_id, now_ms};

impl Store {
    /// Whether `repo_id` has an LFS object with this `oid` recorded.
    ///
    /// # Errors
    ///
    /// Returns [`StoreError::Query`] on a database failure.
    pub async fn lfs_object_exists(&self, repo_id: &str, oid: &str) -> Result<bool, StoreError> {
        let row = sqlx::query("SELECT 1 AS n FROM lfs_objects WHERE repo_id = $1 AND oid = $2")
            .bind(repo_id)
            .bind(oid)
            .fetch_optional(&self.pool)
            .await?;
        Ok(row.is_some())
    }

    /// The stored size (bytes) of an LFS object in `repo_id`, if present.
    ///
    /// # Errors
    ///
    /// Returns [`StoreError::Query`] on a database failure.
    pub async fn lfs_object_size(
        &self,
        repo_id: &str,
        oid: &str,
    ) -> Result<Option<i64>, StoreError> {
        let row = sqlx::query("SELECT size AS n FROM lfs_objects WHERE repo_id = $1 AND oid = $2")
            .bind(repo_id)
            .bind(oid)
            .fetch_optional(&self.pool)
            .await?;
        Ok(row.map(|r| r.try_get("n")).transpose()?)
    }

    /// Record that `repo_id` holds an LFS object (`oid`, `size`). Idempotent: a
    /// repeat upload of the same object is a no-op.
    ///
    /// # Errors
    ///
    /// Returns [`StoreError::Query`] on a database failure.
    pub async fn lfs_object_add(
        &self,
        repo_id: &str,
        oid: &str,
        size: i64,
    ) -> Result<(), StoreError> {
        sqlx::query(
            "INSERT INTO lfs_objects (id, repo_id, oid, size, created_at) \
             VALUES ($1, $2, $3, $4, $5) ON CONFLICT (repo_id, oid) DO NOTHING",
        )
        .bind(new_id())
        .bind(repo_id)
        .bind(oid)
        .bind(size)
        .bind(now_ms())
        .execute(&self.pool)
        .await?;
        Ok(())
    }

    /// The total bytes of LFS objects tracked for `repo_id`.
    ///
    /// # Errors
    ///
    /// Returns [`StoreError::Query`] on a database failure.
    pub async fn lfs_repo_bytes(&self, repo_id: &str) -> Result<i64, StoreError> {
        let n: i64 =
            sqlx::query("SELECT COALESCE(SUM(size), 0) AS n FROM lfs_objects WHERE repo_id = $1")
                .bind(repo_id)
                .fetch_one(&self.pool)
                .await?
                .try_get("n")?;
        Ok(n)
    }
}