//! A tenant connection that keeps its pool alive.

use crate::user::userpool::registry::TenantPool;

use sqlx::pool::PoolConnection;

use sqlx::{PgConnection, Postgres};

use std::ops::{Deref, DerefMut};

use std::sync::Arc;

/// A checked-out connection, holding the tenant pool it came from.

///

/// The anchor is what makes the residency bound true. A permit lives inside

/// [`TenantPool`] and is returned when the last handle drops, so handing back a

/// bare `PoolConnection` released the permit while the connection was still

/// open — sqlx keeps the pool alive behind the connection, so the process could

/// then admit a ninth resident pool and exceed the budget it claims to enforce.

///

/// Dereferences to [`PgConnection`], so `&mut *conn` and `&mut conn` reach an

/// executor exactly as they did before.

pub struct TenantConnection {

    conn: PoolConnection<Postgres>,

    /// `None` for the global/admin pool, which is bounded by its own cap rather

    /// than by residency permits.

    _anchor: Option<Arc<TenantPool>>,

}

impl TenantConnection {

    /// Only the tenant-routing half builds these, and that half is excluded

    /// from server's own `cfg(test)` runs.

    #[cfg(not(test))]

    /// Only the test and `test-utils` arms of `User::get_connection` route a

    /// global connection through the tenant type; production always has a pool.

    #[cfg(any(test, feature = "test-utils"))]

}

impl Deref for TenantConnection {

    type Target = PgConnection;

}

impl DerefMut for TenantConnection {

}