using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using FrameworkDAL.DTO.SessionStore;
using GB5Shared.DTO.Framework.Login;

namespace FrameworkBLL.SessionStore
{
    /// <summary>
    /// Orchestrates MSESSIONSTORE operations for the GB5 system database.
    /// This is the session-management equivalent of BaseEntityAppService —
    /// it is the single authoritative service for all login-session lifecycle events.
    ///
    /// Callers (AuthenticationBLL) go through this BLL; they must never touch
    /// ISessionStoreDAL directly.
    /// </summary>
    public interface ISessionStoreBLL
    {
        /// <summary>
        /// Called on every successful login.
        /// Inserts a new session row or refreshes LASTLOGINUSEDTIME if the session
        /// already exists (safe upsert — handles re-login without duplicate-key errors).
        /// Writes to the GB5 system database regardless of the tenant DB type.
        /// </summary>
        Task InsertSessionAsync(SessionStoreDTO dto, LoginDTO login, CancellationToken ct = default);

        /// <summary>
        /// Called on activity heartbeat to keep the session alive.
        /// Updates LASTLOGINUSEDTIME. No-ops if the session no longer exists.
        /// </summary>
        Task UpdateSessionAsync(int serverConfigId, int loginEventLogId, DateTime lastUsedTime, LoginDTO login, CancellationToken ct = default);

        /// <summary>
        /// Called on explicit logout or forced logout.
        /// Removes the session row from MSESSIONSTORE.
        /// </summary>
        Task DeleteSessionAsync(int serverConfigId, int loginEventLogId, LoginDTO login, CancellationToken ct = default);

        /// <summary>
        /// Called on explicit logout where the caller wants to know whether a session
        /// actually existed (GB4 parity for User.svc's LogOutUser, which reports
        /// "User Successfully LoggedOut." vs "User Not LoggedIn."). Checks for the
        /// session first, deletes it if present, and reports which happened —
        /// unlike <see cref="DeleteSessionAsync"/>, which is fire-and-forget.
        /// </summary>
        Task<bool> LogOutIfPresentAsync(int serverConfigId, int loginEventLogId, LoginDTO login, CancellationToken ct = default);

        /// <summary>
        /// Returns sessions that have been idle longer than <paramref name="expiryMinutes"/>.
        /// Consumed by the auto-logout background job.
        /// </summary>
        Task<IEnumerable<UnusedSessionDTO>> GetUnusedSessionsAsync(int serverConfigId, int expiryMinutes, LoginDTO login, CancellationToken ct = default);

        /// <summary>
        /// Housekeeping — removes session rows older than <paramref name="todayDate"/>
        /// and cleans up orphaned GB5ADMIN rows.
        /// </summary>
        Task DeleteOldSessionsAsync(DateTime todayDate, LoginDTO login, CancellationToken ct = default);
    }
}