Generate Terminal Printable QRCode by Swift

ANSIColor.swift

import Foundation

enum ANSIColor: UInt8 {

    enum Platte: String {
        case WHITE_ALL = "\u{2588}"
        case WHITE_BLACK = "\u{2580}"
        case BLACK_WHITE = "\u{2584}"
        case BLACK_ALL = ""
    }

    case Black = 30, Red, Green, Yellow, Blue, Magenta, Cyan, White
    case BackgroundBlack = 40, BackgroundRed, BackgroundGreen, BackgroundYellow, BackgroundBlue, BackgroundMagenta, BackgroundCyan, BackgroundWhite
    case BrightBlack = 90, BrightRed, BrightGreen, BrightYellow, BrightBlue, BrightMagenta, BrightCyan, BrightWhite

    private static let Reset = "\u{001B}[0m"

    private var color: String {
        return "\u{001B}[\(rawValue)m"
    }

    private var bgColor: String {
        return "\u{001B}[\(rawValue+10)m"
    }

    var fgOutput: String {
        return "\(color)  \(ANSIColor.Reset)"
    }

    var bgOutput: String {
        return "\(bgColor)  \(ANSIColor.Reset)"
    }
}

QRCode.swift

import Foundation
import AppKit

extension String {
    
    func createQRCodeANSI(isSmall small: Bool = false,
                          background backgroundColor: ANSIColor = .White,
                          foreground foregroundColor: ANSIColor = .Black) -> String? {
        guard let filter = CIFilter(name: "CIQRCodeGenerator") else {
            return nil
        }
        filter.setDefaults()
        guard let data = data(using: .utf8) else {
            return nil
        }
        filter.setValue(data, forKey: "inputMessage")
        var outputImg = filter.outputImage
        let colorFilter = CIFilter(name: "CIFalseColor")
        colorFilter?.setDefaults()
        colorFilter?.setValue(outputImg, forKey: "inputImage")
        colorFilter?.setValue(CIColor(color: .white), forKey: "inputColor0")
        colorFilter?.setValue(CIColor(color: .black), forKey: "inputColor1")
        outputImg = colorFilter?.outputImage
        guard let ciImage = outputImg else {
            return nil
        }
        let context = CIContext()
        guard let cgImage = context.createCGImage(ciImage, from: ciImage.extent) else {
            return nil
        }
        let bmpImgRef = NSBitmapImageRep(cgImage: cgImage)
        let w = bmpImgRef.pixelsWide
        let h = bmpImgRef.pixelsHigh
        let blackColor = NSColor.black.usingColorSpace(.genericRGB)
        var result = ""
        for x in 0..<w {
            for y in 0..<h {
                if let color = bmpImgRef.colorAt(x: x, y: y) {
                    if color.usingColorSpace(.genericRGB) == blackColor {
                        result += backgroundColor.bgOutput
                    } else {
                        result += foregroundColor.bgOutput
                    }
                }
            }
            result += "\n"
        }
        return result
    }
}