//! Configuration options to tune the behaviour of [`IdentityMiddleware`].

use std::time::Duration;

use crate::IdentityMiddleware;

#[derive(Debug, Clone)]
pub(crate) struct Configuration {
    pub(crate) on_logout: LogoutBehaviour,
    pub(crate) login_deadline: Option<Duration>,
    pub(crate) visit_deadline: Option<Duration>,
    pub(crate) id_key: &'static str,
    pub(crate) last_visit_unix_timestamp_key: &'static str,
    pub(crate) login_unix_timestamp_key: &'static str,
}

impl Default for Configuration {
    fn default() -> Self {
        Self {
            on_logout: LogoutBehaviour::PurgeSession,
            login_deadline: None,
            visit_deadline: None,
            id_key: "actix_identity.user_id",
            last_visit_unix_timestamp_key: "actix_identity.last_visited_at",
            login_unix_timestamp_key: "actix_identity.logged_in_at",
        }
    }
}

/// `LogoutBehaviour` controls what actions are going to be performed when [`Identity::logout`] is
/// invoked.
///
/// [`Identity::logout`]: crate::Identity::logout
#[derive(Debug, Clone)]
#[non_exhaustive]
pub enum LogoutBehaviour {
    /// When [`Identity::logout`](crate::Identity::logout) is called, purge the current session.
    ///
    /// This behaviour might be desirable when you have stored additional information in the
    /// session state that are tied to the user's identity and should not be retained after logout.
    PurgeSession,

    /// When [`Identity::logout`](crate::Identity::logout) is called, remove the identity
    /// information from the current session state. The session itself is not destroyed.
    ///
    /// This behaviour might be desirable when you have stored information in the session state that
    /// is not tied to the user's identity and should be retained after logout.
    DeleteIdentityKeys,
}

/// A fluent builder to construct an [`IdentityMiddleware`] instance with custom configuration
/// parameters.
///
/// Use [`IdentityMiddleware::builder`] to get started!
#[derive(Debug, Clone)]
pub struct IdentityMiddlewareBuilder {
    configuration: Configuration,
}

impl IdentityMiddlewareBuilder {
    pub(crate) fn new() -> Self {
        Self {
            configuration: Configuration::default(),
        }
    }

    /// Set a custom key to identify the user in the session.
    pub fn id_key(mut self, key: &'static str) -> Self {
        self.configuration.id_key = key;
        self
    }

    /// Set a custom key to store the last visited unix timestamp.
    pub fn last_visit_unix_timestamp_key(mut self, key: &'static str) -> Self {
        self.configuration.last_visit_unix_timestamp_key = key;
        self
    }

    /// Set a custom key to store the login unix timestamp.
    pub fn login_unix_timestamp_key(mut self, key: &'static str) -> Self {
        self.configuration.login_unix_timestamp_key = key;
        self
    }

    /// Determines how [`Identity::logout`](crate::Identity::logout) affects the current session.
    ///
    /// By default, the current session is purged ([`LogoutBehaviour::PurgeSession`]).
    pub fn logout_behaviour(mut self, logout_behaviour: LogoutBehaviour) -> Self {
        self.configuration.on_logout = logout_behaviour;
        self
    }

    /// Automatically logs out users after a certain amount of time has passed since they logged in,
    /// regardless of their activity pattern.
    ///
    /// If set to:
    /// - `None`: login deadline is disabled.
    /// - `Some(duration)`: login deadline is enabled and users will be logged out after `duration`
    ///   has passed since their login.
    ///
    /// By default, login deadline is disabled.
    pub fn login_deadline(mut self, deadline: Option<Duration>) -> Self {
        self.configuration.login_deadline = deadline;
        self
    }

    /// Automatically logs out users after a certain amount of time has passed since their last
    /// visit.
    ///
    /// If set to:
    /// - `None`: visit deadline is disabled.
    /// - `Some(duration)`: visit deadline is enabled and users will be logged out after `duration`
    ///   has passed since their last visit.
    ///
    /// By default, visit deadline is disabled.
    pub fn visit_deadline(mut self, deadline: Option<Duration>) -> Self {
        self.configuration.visit_deadline = deadline;
        self
    }

    /// Finalises the builder and returns an [`IdentityMiddleware`] instance.
    pub fn build(self) -> IdentityMiddleware {
        IdentityMiddleware::new(self.configuration)
    }
}