CIImage+CodeGenerator.swift

//
//  CIImage+CodeGenerator.swift
//
//  Created by Dominik Felber on 04.03.16.
//  Copyright © 2016 Dominik Felber. All rights reserved.
//

import Foundation
import UIKit


extension CIImage {
    enum QRInputCorrectionLevel: String {
        case L = "L" // 7%
        case M = "M" // 15%
        case Q = "Q" // 25%
        case H = "H" // 30%
    }


    func transformedImage(_ size: CGFloat) -> CIImage? {
        guard self.extent.size.width > 0 else {
            return nil
        }
        
        let scale = size / self.extent.size.width
        let transformedImage = self.applying(CGAffineTransform(scaleX: scale, y: scale))
        
        return transformedImage
    }
    
    
    class func createQRCodeImage(for text: String, size: CGFloat, inputCorrectionLevel: QRInputCorrectionLevel = .M) -> CIImage? {
        guard let filter = CIFilter(name: "CIQRCodeGenerator") else {
            return nil
        }
        
        let data = text.data(using: .utf8, allowLossyConversion: true)
        
        filter.setValue(data, forKey: "inputMessage")
        filter.setValue(inputCorrectionLevel.rawValue, forKey: "inputCorrectionLevel")
        
        return filter.outputImage?.transformedImage(size)
    }
    
    
    class func createAztecCodeImage(for text: String, size: CGFloat, inputCorrectionLevel: Float = 23.0, inputLayers: Float = 0.0, inputCompactStyle: Float = 0.0) -> CIImage? {
        guard let filter = CIFilter(name: "CIAztecCodeGenerator") else {
            return nil
        }
        
        let data = text.data(using: .utf8, allowLossyConversion: true)
        
        filter.setValue(data, forKey: "inputMessage")
        
        if inputCorrectionLevel >= 5.0 && inputCorrectionLevel <= 95.0 {
            filter.setValue(inputCorrectionLevel, forKey: "inputCorrectionLevel")
        }
        
        if inputLayers >= 1.0 && inputLayers <= 32.0 {
            filter.setValue(inputLayers, forKey: "inputLayers")
        }
        
        if inputCompactStyle >= 0.0 && inputCompactStyle <= 1.0 {
            filter.setValue(inputCompactStyle, forKey: "inputCompactStyle")
        }
        
        return filter.outputImage?.transformedImage(size)
    }
    
    
    class func createCode128BarcodeImage(for text: String, size: CGFloat, inputQuietSpace: Float = 7.0) -> CIImage? {
        guard let filter = CIFilter(name: "CICode128BarcodeGenerator") else {
            return nil
        }
        
        let data = text.data(using: .ascii, allowLossyConversion: true)
        
        filter.setValue(data, forKey: "inputMessage")
        
        if inputQuietSpace >= 0.0 && inputQuietSpace <= 20.0 {
            filter.setValue(inputQuietSpace, forKey: "inputQuietSpace")
        }
        
        return filter.outputImage?.transformedImage(size)
    }
    
    
    class func createPDF417CodeImage(for text: String, size: CGFloat) -> CIImage? {
        guard let filter = CIFilter(name: "CIPDF417BarcodeGenerator") else {
            return nil
        }
        
        let data = text.data(using: .ascii, allowLossyConversion: true)
        
        filter.setValue(data, forKey: "inputMessage")
        
        return filter.outputImage?.transformedImage(size)
    }
}