Extensions.swift

//
//  Extensions.swift
//
//  Created by Mark Masterson on 4/20/16.
//  Copyright © 2016 Michael Avila. All rights reserved.
//

import Foundation
import UIKit

// MARK: UIImage Extension

extension  UIImage {
    
    func averageColor() -> UIColor {
        
        let rgba = UnsafeMutablePointer<CUnsignedChar>.alloc(4)
        let colorSpace: CGColorSpaceRef = CGColorSpaceCreateDeviceRGB()!
        let info = CGBitmapInfo(rawValue: CGImageAlphaInfo.PremultipliedLast.rawValue)
        let context: CGContextRef = CGBitmapContextCreate(rgba, 1, 1, 8, 4, colorSpace, info.rawValue)!
        
        CGContextDrawImage(context, CGRectMake(0, 0, 1, 1), self.CGImage)
        
        if rgba[3] > 0 {
            
            let alpha: CGFloat = CGFloat(rgba[3]) / 255.0
            let multiplier: CGFloat = alpha / 255.0
            
            return UIColor(red: CGFloat(rgba[0]) * multiplier, green: CGFloat(rgba[1]) * multiplier, blue: CGFloat(rgba[2]) * multiplier, alpha: alpha)
            
        } else {
            
            return UIColor(red: CGFloat(rgba[0]) / 255.0, green: CGFloat(rgba[1]) / 255.0, blue: CGFloat(rgba[2]) / 255.0, alpha: CGFloat(rgba[3]) / 255.0)
        }
    }
    
    public func imageRotatedByDegrees(degrees: CGFloat, flip: Bool) -> UIImage {
        let radiansToDegrees: (CGFloat) -> CGFloat = {
            return $0 * (180.0 / CGFloat(M_PI))
        }
        let degreesToRadians: (CGFloat) -> CGFloat = {
            return $0 / 180.0 * CGFloat(M_PI)
        }
        
        // calculate the size of the rotated view's containing box for our drawing space
        let rotatedViewBox = UIView(frame: CGRect(origin: CGPointZero, size: size))
        let t = CGAffineTransformMakeRotation(degreesToRadians(degrees));
        rotatedViewBox.transform = t
        let rotatedSize = rotatedViewBox.frame.size
        
        // Create the bitmap context
        UIGraphicsBeginImageContext(rotatedSize)
        let bitmap = UIGraphicsGetCurrentContext()
        
        // Move the origin to the middle of the image so we will rotate and scale around the center.
        CGContextTranslateCTM(bitmap, rotatedSize.width / 2.0, rotatedSize.height / 2.0);
        
        //   // Rotate the image context
        CGContextRotateCTM(bitmap, degreesToRadians(degrees));
        
        // Now, draw the rotated/scaled image into the context
        var yFlip: CGFloat
        
        if(flip){
            yFlip = CGFloat(-1.0)
        } else {
            yFlip = CGFloat(1.0)
        }
        
        CGContextScaleCTM(bitmap, yFlip, -1.0)
        CGContextDrawImage(bitmap, CGRectMake(-size.width / 2, -size.height / 2, size.width, size.height), CGImage)
        
        let newImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        
        return newImage
    }
}


//MARK: String Extension
extension String {
    func toBool() -> Bool? {
        switch self {
        case "True", "true", "yes", "1":
            return true
        case "False", "false", "no", "0":
            return false
        default:
            return nil
        }
    }
    
    func contains(find: String) -> Bool{
        return self.rangeOfString(find) != nil
    }

    
    func replace(string:String, replacement:String) -> String {
        return self.stringByReplacingOccurrencesOfString(string, withString: replacement, options: NSStringCompareOptions.LiteralSearch, range: nil)
    }
    
    func removeWhitespace() -> String {
        return self.replace(" ", replacement: "")
    }
    
    
}

// MARK: UIColor Extension

extension UIColor {
    
    func rgb() -> Int? {
        var fRed : CGFloat = 0
        var fGreen : CGFloat = 0
        var fBlue : CGFloat = 0
        var fAlpha: CGFloat = 0
        if self.getRed(&fRed, green: &fGreen, blue: &fBlue, alpha: &fAlpha) {
            let iRed = Int(fRed * 255.0)
            let iGreen = Int(fGreen * 255.0)
            let iBlue = Int(fBlue * 255.0)
            let iAlpha = Int(fAlpha * 255.0)
            
            //  (Bits 24-31 are alpha, 16-23 are red, 8-15 are green, 0-7 are blue).
            let rgb = (iAlpha << 24) + (iRed << 16) + (iGreen << 8) + iBlue
            return rgb
        } else {
            // Could not extract RGBA components:
            return nil
        }
    }
    
    func Luma() -> CGFloat? {
        var fRed : CGFloat = 0
        var fGreen : CGFloat = 0
        var fBlue : CGFloat = 0
        var fAlpha: CGFloat = 0
        if self.getRed(&fRed, green: &fGreen, blue: &fBlue, alpha: &fAlpha) {
            //Y = 0.299 R + 0.587 G + 0.114 B
            let Rmultiplier = CGFloat(0.299)
            let Gmultiplier = CGFloat(0.587)
            let Bmultiplier = CGFloat(0.114)
            
            let Y = (Rmultiplier*fRed)+(Gmultiplier*fGreen)+(Bmultiplier*fBlue)
            
            return Y
        } else {
            // Could not extract RGBA components:
            return nil
        }
    }
    
}

//MARK: UIView Extension

extension UIView {
    func fadeIn(duration: NSTimeInterval = 1.0, delay: NSTimeInterval = 0.0, completion: ((Bool) -> Void) = {(finished: Bool) -> Void in}) {
        UIView.animateWithDuration(duration, delay: delay, options: UIViewAnimationOptions.CurveEaseIn, animations: {
            self.alpha = 1.0
            }, completion: completion)  }
    
    func fadeOut(duration: NSTimeInterval = 1.0, delay: NSTimeInterval = 0.0, completion: (Bool) -> Void = {(finished: Bool) -> Void in}) {
        UIView.animateWithDuration(duration, delay: delay, options: UIViewAnimationOptions.CurveEaseIn, animations: {
            self.alpha = 0.0
            }, completion: completion)
    }
}