WorldSideEnum

WorldSideEnum.swift

//
//  WorldSide.swift
//  
//
//  Created by Bohdan Savych on 5/16/17.
//  Copyright © 2017 Bohdan Savych. All rights reserved.
//

import UIKit

enum WorldSide {
    case north,
    south,
    east,
    west
    
    var opposite: WorldSide {
        switch self {
        case .north:
            return .south
            
        case .south:
            return .north
            
        case .west:
            return .east
            
        case .east:
            return .west
        }
    }
    
    func getAngleByRotating(to side: WorldSide) -> Double {
        if self == side {
            return 0
        }
        
        if self == opposite {
            return -M_PI
        }
        
        switch self {
        case .east:
            return side == .north ? M_PI_2 : -M_PI_2
        
        case .west:
            return side == .south ? M_PI_2 : -M_PI_2
            
        case .north:
            return side == .west ? M_PI_2 : -M_PI_2
            
        case .south:
            return side == .east ? M_PI_2 : -M_PI_2
        }
    }
}