#region References
using System;

using Server.Commands;
using Server.Items;
using Server.Network;
#endregion

namespace Server
{
	public static class LightCycle
    {
        public const int DayLevel = 0;
        public const int NightLevel = 12;
        public const int DungeonLevel = 26;
        public const int JailLevel = 9;

		private static int _LevelOverride = Int32.MinValue;

        public static int LevelOverride
        {
			get { return _LevelOverride; }
            set
            {
				_LevelOverride = value;

				CheckLightLevels();
            }
        }

        public static void Initialize()
        {
			new LightCycleTimer(Clock.SecondsPerUOMinute).Start();

			EventSink.Login += OnLogin;

			CommandSystem.Register("GlobalLight", AccessLevel.GameMaster, Light_OnCommand);
        }

        public static void OnLogin(LoginEventArgs args)
        {
			var m = args.Mobile;

			if (m != null)
            	m.CheckLightLevels(true);
        }

        public static int ComputeLevelFor(Mobile from)
        {
			if (_LevelOverride > int.MinValue)
				return _LevelOverride;

            int hours, minutes;

			Clock.GetTime(from.Map, from.X, from.Y, out hours, out minutes);

            /* OSI times:
            * 
            * Midnight ->  3:59 AM : Night
            *  4:00 AM -> 11:59 PM : Day
            * 
            * RunUO times:
            * 
            * 10:00 PM -> 11:59 PM : Scale to night
            * Midnight ->  3:59 AM : Night
            *  4:00 AM ->  5:59 AM : Scale to day
            *  6:00 AM ->  9:59 PM : Day
            */

            if (hours < 4)
                return NightLevel;

            if (hours < 6)
                return NightLevel + (((((hours - 4) * 60) + minutes) * (DayLevel - NightLevel)) / 120);

            if (hours < 22)
                return DayLevel;

            if (hours < 24)
                return DayLevel + (((((hours - 22) * 60) + minutes) * (NightLevel - DayLevel)) / 120);

            return NightLevel; // should never be
        }

		public static void CheckLightLevels()
		{
			var i = NetState.Instances.Count;

			while (--i >= 0)
			{
				if (i >= NetState.Instances.Count)
					continue;

				var ns = NetState.Instances[i];

				if (ns == null)
					continue;

				var m = ns.Mobile;

				if (m != null)
					m.CheckLightLevels(false);
			}
		}

        [Usage("GlobalLight <value>")]
        [Description("Sets the current global light level.")]
        private static void Light_OnCommand(CommandEventArgs e)
        {
            if (e.Length >= 1)
            {
                LevelOverride = e.GetInt32(0);
				e.Mobile.SendMessage("Global light level override has been changed to {0}.", _LevelOverride);
            }
            else
            {
                LevelOverride = int.MinValue;
                e.Mobile.SendMessage("Global light level override has been cleared.");
            }
        }

        public class NightSightTimer : Timer
        {
            private readonly Mobile m_Owner;

            public NightSightTimer(Mobile owner)
                : base(TimeSpan.FromMinutes(Utility.Random(15, 25)))
            {
				m_Owner = owner;

				Priority = TimerPriority.OneMinute;
            }

            protected override void OnTick()
            {
				m_Owner.EndAction(typeof(LightCycle));
				m_Owner.LightLevel = 0;

				BuffInfo.RemoveBuff(m_Owner, BuffIcon.NightSight);
            }
        }

        private class LightCycleTimer : Timer
        {
			public LightCycleTimer(double interval)
				: base(TimeSpan.Zero, TimeSpan.FromSeconds(interval))
            {
				Priority = TimerPriority.OneSecond;
            }

            protected override void OnTick()
            {
				CheckLightLevels();
            }
        }
    }
}