using System;
using System.Threading;
using System.Threading.Tasks;
using SharedLibraryCore.Objects;

namespace SharedLibraryCore
{
    public class GameEvent
    {
        public enum EventFailReason
        {
            /// <summary>
            /// event execution did not fail
            /// </summary>
            None,
            /// <summary>
            /// an internal exception prevented the event
            /// from executing
            /// </summary>
            Exception,
            /// <summary>
            /// event origin didn't have the necessary privileges
            /// to execute the command
            /// </summary>
            Permission,
            /// <summary>
            /// executing the event would cause an invalid state
            /// </summary>
            Invalid,
            /// <summary>
            /// client is doing too much of something
            /// </summary>
            Throttle
        }

        public enum EventType
        {
            /// <summary>
            /// the event wasn't parsed properly
            /// </summary>
            Unknown,

            // events "generated" by the server
            /// <summary>
            /// a server started being monitored
            /// </summary>
            Start,
            /// <summary>
            /// a server stopped being monitored
            /// </summary>
            Stop,
            /// <summary>
            /// a client was detecting as connecting via RCon
            /// </summary>
            Connect,
            /// <summary>
            /// a client was detecting joining via log
            /// </summary>
            Join,
            /// <summary>
            /// a client was detected leaving via log
            /// </summary>
            Quit,
            /// <summary>
            /// a client was detected leaving by RCon
            /// </summary>
            Disconnect,
            /// <summary>
            /// the current map ended
            /// </summary>
            MapEnd,
            /// <summary>
            /// the current map changed
            /// </summary>
            MapChange,

            // events "generated" by clients  
            /// <summary>
            /// a client sent a message
            /// </summary>
            Say = 100,
            /// <summary>
            /// a client was warned
            /// </summary>
            Warn = 101,
            /// <summary>
            /// all warnings for a client were cleared
            /// </summary>
            WarnClear = 102,
            /// <summary>
            /// a client was reported
            /// </summary>
            Report = 103,
            /// <summary>
            /// a client was flagged
            /// </summary>
            Flag = 104,
            /// <summary>
            /// a client was unflagged
            /// </summary>
            Unflag = 105,
            /// <summary>
            /// a client was kicked
            /// </summary>
            Kick = 106,
            /// <summary>
            /// a client was tempbanned
            /// </summary>
            TempBan = 107,
            /// <summary>
            /// a client was banned
            /// </summary>
            Ban = 108,
            /// <summary>
            /// a client was unbanned
            /// </summary>
            Unban = 109,
            /// <summary>
            /// a client entered a command
            /// </summary>
            Command = 110,
            /// <summary>
            /// a client's permission was changed
            /// </summary>
            ChangePermission = 111,

            // events "generated" by IW4MAdmin
            /// <summary>
            /// a message is sent to all clients
            /// </summary>
            Broadcast = 200,
            /// <summary>
            /// a message is sent to a specific client
            /// </summary>
            Tell = 201,

            // events "generated" by script/log
            /// <summary>
            /// AC Damage Log
            /// </summary>
            ScriptDamage = 300,
            /// <summary>
            /// AC Kill Log
            /// </summary>
            ScriptKill = 301,
            /// <summary>
            /// damage info printed out by game script
            /// </summary>
            Damage = 302,
            /// <summary>
            /// kill info printed out by game script
            /// </summary>
            Kill = 303,
            /// <summary>
            /// team info printed out by game script
            /// </summary>
            JoinTeam = 304,
        }

        static long NextEventId;
        static long GetNextEventId() => Interlocked.Increment(ref NextEventId);

        public GameEvent()
        {
            OnProcessed = new ManualResetEventSlim(false);
            Time = DateTime.UtcNow;
            Id = GetNextEventId();
        }

        public EventType Type;
        public string Data; // Data is usually the message sent by player
        public string Message;
        public Player Origin;
        public Player Target;
        public Server Owner;
        public Boolean Remote = false;
        public object Extra { get; set; }
        public ManualResetEventSlim OnProcessed { get; set; }
        public DateTime Time { get; set; }
        public long Id { get; private set; }
        public EventFailReason FailReason { get; set; }
        public bool Failed => FailReason != EventFailReason.None;

        /// <summary>
        /// asynchronously wait for GameEvent to be processed
        /// </summary>
        /// <returns>waitable task </returns>
        public Task<GameEvent> WaitAsync(int timeOut = int.MaxValue) => Task.Run(() =>
        {
            OnProcessed.Wait(timeOut);
            return this;
        });

        /// <summary>
        /// determine whether an event should be delayed or not
        /// applies only to the origin entity
        /// </summary>
        /// <param name="queuedEvent">event to determine status for</param>
        /// <returns>true if event should be delayed, false otherwise</returns>
        public static bool ShouldOriginEventBeDelayed(GameEvent queuedEvent)
        {
            return queuedEvent.Origin != null &&
                                    (queuedEvent.Origin.State != Player.ClientState.Connected &&
                                    // we want to allow join and quit events
                                    queuedEvent.Type != EventType.Connect &&
                                    queuedEvent.Type != EventType.Join &&
                                    queuedEvent.Type != EventType.Quit &&
                                    queuedEvent.Type != EventType.Disconnect &&
                                    // we don't care about unknown events
                                    queuedEvent.Origin.NetworkId != 0);
        }

        /// <summary>
        /// determine whether an event should be delayed or not
        /// applies only to the target entity
        /// </summary>
        /// <param name="queuedEvent">event to determine status for</param>
        /// <returns>true if event should be delayed, false otherwise</returns>
        public static bool ShouldTargetEventBeDelayed(GameEvent queuedEvent)
        {
            return (queuedEvent.Target != null && queuedEvent.Target.ClientNumber != -1) &&
                                    (queuedEvent.Target.State != Player.ClientState.Connected &&
                                    queuedEvent.Target.NetworkId != 0 &&
                                    queuedEvent.Origin?.ClientId != 1);
        }
    }
}