using System;
using System.Collections;
using Server.Network;
using Server.Accounting;

namespace Server.RemoteAdmin
{
	public class RemoteAdminHandlers
	{
		public enum AcctSearchType : byte
		{
			Username = 0,
			IP = 1,
		}

		private static OnPacketReceive[] m_Handlers = new OnPacketReceive[256];

		static RemoteAdminHandlers()
		{
			//0x02 = login request, handled by AdminNetwork
			Register( 0x04, ServerInfoRequest );
			Register( 0x05, AccountSearch );
			Register( 0x06, RemoveAccount );
			Register( 0x07, UpdateAccount );
		}

		public static void Register( byte command, OnPacketReceive handler )
		{
			m_Handlers[command] = handler;
		}

		public static bool Handle( byte command, NetState state, PacketReader pvSrc )
		{
			if ( m_Handlers[command] == null )
			{
				Console.WriteLine( "ADMIN: Invalid packet 0x{0:X2} from {1}, disconnecting", command, state );
				return false;
			}

			m_Handlers[command]( state, pvSrc );
			return true;
		}

		private static void ServerInfoRequest( NetState state, PacketReader pvSrc )
		{
			state.Send( AdminNetwork.Compress( new ServerInfo() ) );
		}

		private static void AccountSearch( NetState state, PacketReader pvSrc )
		{
			AcctSearchType type = (AcctSearchType)pvSrc.ReadByte();
			string term = pvSrc.ReadString();

			if ( type == AcctSearchType.IP && !Utility.IsValidIP( term ) )
			{
				state.Send( new MessageBoxMessage( "Invalid search term.\nThe IP sent was not valid.", "Invalid IP" ) );
				return;
			}

			term = term.ToUpper();

			ArrayList list = new ArrayList();

			foreach ( Account a in Accounts.GetAccounts() )
			{
				if ( !CanAccessAccount( state.Account, a ) ) continue;

				switch ( type )
				{
					case AcctSearchType.Username:
					{
						if ( a.Username.ToUpper().IndexOf( term ) != -1 )
							list.Add( a );
						break;
					}
					case AcctSearchType.IP:
					{
						for( int i=0;i<a.LoginIPs.Length;i++ )
						{
							if ( Utility.IPMatch( term, a.LoginIPs[i] ) )
							{
								list.Add( a );
								break;
							}
						}
						break;
					}
				}
			}

			if ( list.Count > 0 )
			{
				if ( list.Count <= 25 )
					state.Send( AdminNetwork.Compress( new AccountSearchResults( list ) ) );
				else
					state.Send( new MessageBoxMessage( "There were more than 25 matches to your search.\nNarrow the search parameters and try again.", "Too Many Results" ) );
			}
			else
			{
				state.Send( new MessageBoxMessage( "There were no results to your search.\nPlease try again.", "No Matches" ) );
			}
		}

		static bool CanAccessAccount( IAccount beholder, IAccount beheld )
		{
			return beholder.AccessLevel == AccessLevel.Owner || beheld.AccessLevel < beholder.AccessLevel;  // Cannot see accounts of equal or greater access level unless Owner
		}

		private static void RemoveAccount( NetState state, PacketReader pvSrc )
		{
			if ( state.Account.AccessLevel < AccessLevel.Administrator )
			{
				state.Send( new MessageBoxMessage( "You do not have permission to delete accounts.", "Account Access Exception" ) );
				return;
			}

			IAccount a = Accounts.GetAccount( pvSrc.ReadString() );

			if ( a == null )
			{
				state.Send( new MessageBoxMessage( "The account could not be found (and thus was not deleted).", "Account Not Found" ) );
			}
			else if ( !CanAccessAccount( state.Account, a ) )
			{
				state.Send( new MessageBoxMessage( "You cannot delete an account with an access level greater than or equal to your own.", "Account Access Exception" ) );
			}
			else if ( a == state.Account )
			{
				state.Send( new MessageBoxMessage( "You may not delete your own account.", "Not Allowed" ) );
			}
			else
			{
				RemoteAdminLogging.WriteLine( state, "Deleted Account {0}", a );
				a.Delete();
				state.Send( new MessageBoxMessage( "The requested account (and all it's characters) has been deleted.", "Account Deleted" ) );
			}
		}

		private static void UpdateAccount( NetState state, PacketReader pvSrc )
		{ 
			if ( state.Account.AccessLevel < AccessLevel.Administrator )
			{
				state.Send( new MessageBoxMessage( "You do not have permission to edit accounts.", "Account Access Exception" ) );
				return;
			}

			string username = pvSrc.ReadString();
			string pass = pvSrc.ReadString();

			Account a = Accounts.GetAccount( username ) as Account;

			if ( a != null && !CanAccessAccount( state.Account, a ) )
			{
				state.Send( new MessageBoxMessage( "You cannot edit an account with an access level greater than or equal to your own.", "Account Access Exception" ) );
			}
			else
			{
				bool CreatedAccount = false;
				bool UpdatedPass = false;
				bool oldbanned = a?.Banned ?? false;
				AccessLevel oldAcessLevel = a?.AccessLevel ?? 0;

				if ( a == null )
				{
					a = new Account( username, pass );
					CreatedAccount = true;
				}
				else if ( pass != "(hidden)" )
				{
					a.SetPassword( pass );
					UpdatedPass = true;
				}

				if ( a != state.Account )
				{
					AccessLevel newAccessLevel = (AccessLevel)pvSrc.ReadByte();
					if ( a.AccessLevel != newAccessLevel )
					{
						if ( newAccessLevel >= state.Account.AccessLevel )
							state.Send( new MessageBoxMessage( "Warning: You may not set an access level greater than or equal to your own.", "Account Access Level update denied." ) );
						else
							a.AccessLevel = newAccessLevel;
					}
					bool newBanned = pvSrc.ReadBoolean();
					if ( newBanned != a.Banned )
					{
						oldbanned = a.Banned;
						a.Banned = newBanned;
						a.Comments.Add( new AccountComment( state.Account.Username, newBanned ? "Banned via Remote Admin" : "Unbanned via Remote Admin" ) );
					}
				}
				else
				{
					pvSrc.ReadInt16();//skip both
					state.Send( new MessageBoxMessage( "Warning: When editing your own account, Account Status and Access Level cannot be changed.", "Editing Own Account" ) );
				}

				ArrayList list = new ArrayList();
				ushort length = pvSrc.ReadUInt16();
				bool invalid = false;
				for (int i=0;i<length;i++)
				{
					string add = pvSrc.ReadString();
					if ( Utility.IsValidIP( add ) )
						list.Add( add );
					else
						invalid = true;
				}

				if ( list.Count > 0 )
					a.IPRestrictions = (string[])list.ToArray( typeof( string ) );
				else
					a.IPRestrictions = new string[0];

				if ( invalid )
					state.Send( new MessageBoxMessage( "Warning: one or more of the IP Restrictions you specified was not valid.", "Invalid IP Restriction" ) );

				if ( CreatedAccount )
					RemoteAdminLogging.WriteLine( state, "Created account {0} with Access Level {1}", a.Username, a.AccessLevel );
				else
				{
					string changes = string.Empty;
					if ( UpdatedPass ) changes += " Password Changed.";
					if ( oldAcessLevel != a.AccessLevel ) changes =
						$"{changes} Access level changed from {oldAcessLevel} to {a.AccessLevel}.";
					if ( oldbanned != a.Banned ) changes += a.Banned ? " Banned." : " Unbanned.";
					RemoteAdminLogging.WriteLine( state, "Updated account {0}:{1}", a.Username, changes );
				}

				state.Send( new MessageBoxMessage( "Account updated successfully.", "Account Updated" ) );
			}
		}
	}
}