Drone.Rotation

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

// Need this for playerposition info
using BattleCore.Events;

namespace Drone
{
    class Rotation
    {
        private byte _DefaultRotation;

        private ushort _DroneX;
        private ushort _DroneY;

        /// <summary>
        /// Set drone position
        /// </summary>
        /// <param name="x">x coord</param>
        /// <param name="y">y coord</param>
        /// <param name="rotation">rotation drone returns to when there are no targets.</param>
        public void SetVariables(ushort x, ushort y, byte rotation)
        {
            _DroneX = x;
            _DroneY = y;
            _DefaultRotation = rotation;
        }

        /// <summary>
        /// This will increment 1 rotation toward the target.
        /// </summary>
        /// <param name="position">Player position packet.</param>
        /// <param name="NewRotation">Rotation to target.</param>
        public void UpdatedRotation(PlayerPositionEvent position, byte NewRotation)
        {
            if (position.ShipRotation != NewRotation)
            {
                // Special circumstance if ActR == 19
                if ((position.ShipRotation == 39) && (NewRotation <= 19))
                    position.ShipRotation = 0;
                // Special circumstance if ActR == 0
                else if (position.ShipRotation == 0)
                {
                    if (NewRotation <= 20)
                        position.ShipRotation++;
                    else
                        position.ShipRotation = 39;
                }
                else if (NewRotation > position.ShipRotation)
                {
                    if (NewRotation - position.ShipRotation < 20)
                        position.ShipRotation++;
                    else
                        position.ShipRotation--;
                }
                else
                {
                    if (position.ShipRotation - NewRotation < 20)
                        position.ShipRotation--;
                    else
                        position.ShipRotation++;
                }
            }
        }
        /// <summary>
        /// If no target is found in the area have drone return to default rotation.
        /// </summary>
        /// <param name="position">Player position packet.</param>
        public void NoTarget(PlayerPositionEvent position)
        {
            UpdatedRotation(position, _DefaultRotation);
        }
        public byte RotationToTarget(ushort PlayerPosX, ushort PlayerPosY)
        {
            //setting info to variables (i can take this out later)
            ushort play_x = PlayerPosX;
            ushort play_y = PlayerPosY;
            ushort bot_x = _DroneX;
            ushort bot_y = _DroneY;

            // Formula to extract an angle
            double angle = Math.Atan((double)(play_y - bot_y) / (double)(play_x - bot_x)) * (180.0 / 3.14159);
            byte rot = 0;

            // with formula we get 0-90 degrees for each quadrant
            // here we simply find out which quadrant it is and add the proper increment to make it rotation 0-39
            if (play_x > bot_x)
            {
                if (play_y > bot_y)// Lower Right
                {
                    rot = (byte)Math.Floor((angle / 9) + 10);
                }
                else if (play_y < bot_y)// Top Right
                {
                    rot = (byte)Math.Floor((90 + angle) / 9);
                }
            }
            else if (play_x < bot_x)
            {
                if (play_y > bot_y)// Lower Left
                {
                    rot = (byte)Math.Floor(((90 + angle) / 9) + 19);
                }
                else if (play_y < bot_y)// Top Left
                {
                    rot = (byte)Math.Floor((angle / 9) + 29);
                }
            }
            return rot;
        }
    }
}