using System;
using System.Net;
using Server.Mobiles;
using System.Collections.Generic;

namespace Server.Factions
{
	public class Election
	{
		public static readonly TimeSpan PendingPeriod = TimeSpan.FromDays( 5.0 );
		public static readonly TimeSpan CampaignPeriod = TimeSpan.FromDays( 1.0 );
		public static readonly TimeSpan VotingPeriod = TimeSpan.FromDays( 3.0 );

		public const int MaxCandidates = 10;
		public const int CandidateRank = 5;

		public Faction Faction { get; }

		public List<Candidate> Candidates { get; }

		public ElectionState State{ get => CurrentState;
			set{ CurrentState = value; LastStateTime = DateTime.UtcNow; } }
		public DateTime LastStateTime { get; private set; }

		[CommandProperty( AccessLevel.GameMaster )]
		public ElectionState CurrentState { get; private set; }

		[CommandProperty( AccessLevel.GameMaster, AccessLevel.Administrator )]
		public TimeSpan NextStateTime
		{
			get
			{
				TimeSpan period;

				switch ( CurrentState )
				{
					default:
					case ElectionState.Pending: period = PendingPeriod; break;
					case ElectionState.Election: period = VotingPeriod; break;
					case ElectionState.Campaign: period = CampaignPeriod; break;
				}

				TimeSpan until = (LastStateTime + period) - DateTime.UtcNow;

				if ( until < TimeSpan.Zero )
					until = TimeSpan.Zero;

				return until;
			}
			set
			{
				TimeSpan period;

				switch ( CurrentState )
				{
					default:
					case ElectionState.Pending: period = PendingPeriod; break;
					case ElectionState.Election: period = VotingPeriod; break;
					case ElectionState.Campaign: period = CampaignPeriod; break;
				}

				LastStateTime = DateTime.UtcNow - period + value;
			}
		}

		private Timer m_Timer;

		public void StartTimer()
		{
			m_Timer = Timer.DelayCall( TimeSpan.FromMinutes( 1.0 ), TimeSpan.FromMinutes( 1.0 ), Slice );
		}

		public Election( Faction faction )
		{
			Faction = faction;
			Candidates = new List<Candidate>();

			StartTimer();
		}

		public Election( GenericReader reader )
		{
			int version = reader.ReadEncodedInt();

			switch ( version )
			{
				case 0:
				{
					Faction = Faction.ReadReference( reader );

					LastStateTime = reader.ReadDateTime();
					CurrentState = (ElectionState)reader.ReadEncodedInt();

					Candidates = new List<Candidate>();

					int count = reader.ReadEncodedInt();

					for ( int i = 0; i < count; ++i )
					{
						Candidate cd = new Candidate( reader );

						if ( cd.Mobile != null )
							Candidates.Add( cd );
					}

					break;
				}
			}

			StartTimer();
		}

		public void Serialize( GenericWriter writer )
		{
			writer.WriteEncodedInt( (int) 0 ); // version

			Faction.WriteReference( writer, Faction );

			writer.Write( (DateTime) LastStateTime );
			writer.WriteEncodedInt( (int) CurrentState );

			writer.WriteEncodedInt( Candidates.Count );

			for ( int i = 0; i < Candidates.Count; ++i )
				Candidates[i].Serialize( writer );
		}

		public void AddCandidate( Mobile mob )
		{
			if ( IsCandidate( mob ) )
				return;

			Candidates.Add( new Candidate( mob ) );
			mob.SendLocalizedMessage( 1010117 ); // You are now running for office.
		}

		public void RemoveVoter( Mobile mob )
		{
			if ( CurrentState == ElectionState.Election )
			{
				for ( int i = 0; i < Candidates.Count; ++i )
				{
					List<Voter> voters = Candidates[i].Voters;

					for ( int j = 0; j < voters.Count; ++j )
					{
						Voter voter = voters[j];

						if ( voter.From == mob )
							voters.RemoveAt( j-- );
					}
				}
			}
		}

		public void RemoveCandidate( Mobile mob )
		{
			Candidate cd = FindCandidate( mob );

			if ( cd == null )
				return;

			Candidates.Remove( cd );
			mob.SendLocalizedMessage( 1038031 );

			if ( CurrentState == ElectionState.Election )
			{
				if ( Candidates.Count == 1 )
				{
					Faction.Broadcast( 1038031 ); // There are no longer any valid candidates in the Faction Commander election.

					Candidate winner = Candidates[0];

					Mobile winMob = winner.Mobile;
					PlayerState pl = PlayerState.Find( winMob );

					if ( pl == null || pl.Faction != Faction || winMob == Faction.Commander )
					{
						Faction.Broadcast( 1038026 ); // Faction leadership has not changed.
					}
					else
					{
						Faction.Broadcast( 1038028 ); // The faction has a new commander.
						Faction.Commander = winMob;
					}

					Candidates.Clear();
					State = ElectionState.Pending;
				}
				else if ( Candidates.Count == 0 ) // well, I guess this'll never happen
				{
					Faction.Broadcast( 1038031 ); // There are no longer any valid candidates in the Faction Commander election.

					Candidates.Clear();
					State = ElectionState.Pending;
				}
			}
		}

		public bool IsCandidate( Mobile mob )
		{
			return ( FindCandidate( mob ) != null );
		}

		public bool CanVote( Mobile mob )
		{
			return ( CurrentState == ElectionState.Election && !HasVoted( mob ) );
		}

		public bool HasVoted( Mobile mob )
		{
			return ( FindVoter( mob ) != null );
		}

		public Candidate FindCandidate( Mobile mob )
		{
			for ( int i = 0; i < Candidates.Count; ++i )
			{
				if ( Candidates[i].Mobile == mob )
					return Candidates[i];
			}

			return null;
		}

		public Candidate FindVoter( Mobile mob )
		{
			for ( int i = 0; i < Candidates.Count; ++i )
			{
				List<Voter> voters = Candidates[i].Voters;

				for ( int j = 0; j < voters.Count; ++j )
				{
					Voter voter = voters[j];

					if ( voter.From == mob )
						return Candidates[i];
				}
			}

			return null;
		}

		public bool CanBeCandidate( Mobile mob )
		{
			if ( IsCandidate( mob ) )
				return false;

			if ( Candidates.Count >= MaxCandidates )
				return false;

			if ( CurrentState != ElectionState.Campaign )
				return false; // sanity..

			PlayerState pl = PlayerState.Find( mob );

			return ( pl != null && pl.Faction == Faction && pl.Rank.Rank >= CandidateRank );
		}

		public void Slice()
		{
			if ( Faction.Election != this )
			{
				m_Timer?.Stop();

				m_Timer = null;

				return;
			}

			switch ( CurrentState )
			{
				case ElectionState.Pending:
				{
					if ( (LastStateTime + PendingPeriod) > DateTime.UtcNow )
						break;

					Faction.Broadcast( 1038023 ); // Campaigning for the Faction Commander election has begun.

					Candidates.Clear();
					State = ElectionState.Campaign;

					break;
				}
				case ElectionState.Campaign:
				{
					if ( (LastStateTime + CampaignPeriod) > DateTime.UtcNow )
						break;

					if ( Candidates.Count == 0 )
					{
						Faction.Broadcast( 1038025 ); // Nobody ran for office.
						State = ElectionState.Pending;
					}
					else if ( Candidates.Count == 1 )
					{
						Faction.Broadcast( 1038029 ); // Only one member ran for office.

						Candidate winner = Candidates[0];

						Mobile mob = winner.Mobile;
						PlayerState pl = PlayerState.Find( mob );

						if ( pl == null || pl.Faction != Faction || mob == Faction.Commander )
						{
							Faction.Broadcast( 1038026 ); // Faction leadership has not changed.
						}
						else
						{
							Faction.Broadcast( 1038028 ); // The faction has a new commander.
							Faction.Commander = mob;
						}

						Candidates.Clear();
						State = ElectionState.Pending;
					}
					else
					{
						Faction.Broadcast( 1038030 );
						State = ElectionState.Election;
					}

					break;
				}
				case ElectionState.Election:
				{
					if ( (LastStateTime + VotingPeriod) > DateTime.UtcNow )
						break;

					Faction.Broadcast( 1038024 ); // The results for the Faction Commander election are in

					Candidate winner = null;

					for ( int i = 0; i < Candidates.Count; ++i )
					{
						Candidate cd = Candidates[i];

						PlayerState pl = PlayerState.Find( cd.Mobile );

						if ( pl == null || pl.Faction != Faction )
							continue;

						//cd.CleanMuleVotes();

						if ( winner == null || cd.Votes > winner.Votes )
							winner = cd;
					}

					if ( winner == null )
					{
						Faction.Broadcast( 1038026 ); // Faction leadership has not changed.
					}
					else if ( winner.Mobile == Faction.Commander )
					{
						Faction.Broadcast( 1038027 ); // The incumbent won the election.
					}
					else
					{
						Faction.Broadcast( 1038028 ); // The faction has a new commander.
						Faction.Commander = winner.Mobile;
					}

					Candidates.Clear();
					State = ElectionState.Pending;

					break;
				}
			}
		}
	}

	public class Voter
	{
		public Mobile From { get; }

		public Mobile Candidate { get; }

		public IPAddress Address { get; }

		public DateTime Time { get; }

		public object[] AcquireFields()
		{
			TimeSpan gameTime = TimeSpan.Zero;

			if ( From is PlayerMobile mobile )
				gameTime = mobile.GameTime;

			int kp = 0;

			PlayerState pl = PlayerState.Find( From );

			if ( pl != null )
				kp = pl.KillPoints;

			int sk = From.Skills.Total;

			int factorSkills = 50 + ( (sk * 100 ) / 10000 );
			int factorKillPts = 100 + (kp*2);
			int factorGameTime = 50 + (int) ( (gameTime.Ticks * 100) / TimeSpan.TicksPerDay );

			int totalFactor = ( factorSkills * factorKillPts * Math.Max( factorGameTime, 100 ) ) / 10000;

			if ( totalFactor > 100 )
				totalFactor = 100;
			else if ( totalFactor < 0 )
				totalFactor = 0;

			return new object[]{ From, Address, Time, totalFactor };
		}

		public Voter( Mobile from, Mobile candidate )
		{
			From = from;
			Candidate = candidate;

			if ( From.NetState != null )
				Address = From.NetState.Address;
			else
				Address = IPAddress.None;

			Time = DateTime.UtcNow;
		}

		public Voter( GenericReader reader, Mobile candidate )
		{
			Candidate = candidate;

			int version = reader.ReadEncodedInt();

			switch ( version )
			{
				case 0:
				{
					From = reader.ReadMobile();
					Address = Utility.Intern( reader.ReadIPAddress() );
					Time = reader.ReadDateTime();

					break;
				}
			}
		}

		public void Serialize( GenericWriter writer )
		{
			writer.WriteEncodedInt( (int) 0 );

			writer.Write( (Mobile) From );
			writer.Write( (IPAddress) Address );
			writer.Write( (DateTime) Time );
		}
	}

	public class Candidate
	{
		public Mobile Mobile { get; }

		public List<Voter> Voters { get; }

		public int Votes => Voters.Count;

		public void CleanMuleVotes()
		{
			for ( int i = 0; i < Voters.Count; ++i )
			{
				Voter voter = (Voter)Voters[i];

				if ( (int)voter.AcquireFields()[3] < 90 )
					Voters.RemoveAt( i-- );
			}
		}

		public Candidate( Mobile mob )
		{
			Mobile = mob;
			Voters = new List<Voter>();
		}

		public Candidate( GenericReader reader )
		{
			int version = reader.ReadEncodedInt();

			switch ( version )
			{
				case 1:
				{
					Mobile = reader.ReadMobile();

					int count = reader.ReadEncodedInt();
					Voters = new List<Voter>( count );

					for ( int i = 0; i < count; ++i )
					{
						Voter voter = new Voter( reader, Mobile );

						if ( voter.From != null )
							Voters.Add( voter );
					}

					break;
				}
				case 0:
				{
					Mobile = reader.ReadMobile();

					List<Mobile> mobs = reader.ReadStrongMobileList();
					Voters = new List<Voter>( mobs.Count );

					for ( int i = 0; i < mobs.Count; ++i )
						Voters.Add( new Voter( mobs[i], Mobile ) );

					break;
				}
			}
		}

		public void Serialize( GenericWriter writer )
		{
			writer.WriteEncodedInt( (int) 1 ); // version

			writer.Write( (Mobile) Mobile );

			writer.WriteEncodedInt( (int) Voters.Count );

			for ( int i = 0; i < Voters.Count; ++i )
				((Voter)Voters[i]).Serialize( writer );
		}
	}

	public enum ElectionState
	{
		Pending,
		Campaign,
		Election
	}
}