use async_trait::async_trait;
use thiserror::Error;

/// The Trait used to identify a database pool.
///
/// This can be freely implemented but default implementations for the supported database types are already included
/// If you're using a custom database library than you should use the Generic*Error in the DatabaseError enum to indicate an error.
#[async_trait]
pub trait DatabasePool {
    /// This is called to create the table in the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn initiate(&self, table_name: &str) -> Result<(), DatabaseError>;

    /// This is called to receive the session count in the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn count(&self, table_name: &str) -> Result<i64, DatabaseError>;

    /// This is called to store a session in the database using the given table name.
    /// The session is a string and should be stored in its own field.
    /// if an error occurs it should be propagated to the caller.
    /// expires is a unix timestamp(number of non-leap seconds since January 1, 1970 0:00:00 UTC)
    /// which is set to UTC::now() + the expiration time.
    async fn store(
        &self,
        id: &str,
        session: &str,
        expires: i64,
        table_name: &str,
    ) -> Result<(), DatabaseError>;

    /// This is called to receive the session from the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn load(&self, id: &str, table_name: &str) -> Result<Option<String>, DatabaseError>;

    /// This is called to delete one session from the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn delete_one_by_id(&self, id: &str, table_name: &str) -> Result<(), DatabaseError>;

    /// This is called to check if the id exists in the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn exists(&self, id: &str, table_name: &str) -> Result<bool, DatabaseError>;

    /// This is called to delete all sessions that expired from the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn delete_by_expiry(&self, table_name: &str) -> Result<Vec<String>, DatabaseError>;

    /// This is called to delete all sessions from the database using the given table name.
    /// if an error occurs it should be propagated to the caller.
    async fn delete_all(&self, table_name: &str) -> Result<(), DatabaseError>;

    /// This is called to get all id's in the database from the last run.
    /// if an error occurs it should be propagated to the caller.
    async fn get_ids(&self, table_name: &str) -> Result<Vec<String>, DatabaseError>;

    fn auto_handles_expiry(&self) -> bool;
}

#[derive(Error, Debug)]
pub enum DatabaseError {
    #[error("Database insert error {0}")]
    GenericAcquire(String),
    #[error("Database insert error {0}")]
    GenericInsertError(String),
    #[error("Database select error {0}")]
    GenericSelectError(String),
    #[error("Database create error {0}")]
    GenericCreateError(String),
    #[error("Database delete error {0}")]
    GenericDeleteError(String),
    #[error("{0}")]
    GenericNotSupportedError(String),
}