Design patterns by Tutorials - The power of OOP (part 3) - Adapter pattern simple solution example - https://medium.com/p/112a956c1101

AdapterPattern_simpleSolution.swift

// Hitendra Solanki
// Adapter design pattern Playground example

import Foundation

class Point {
    var x: Int
    var y: Int
    
    init(x: Int, y: Int) {
        self.x = x
        self.y = y
    }
}

class LineSegment {
    var startPoint: Point
    var endPoint:   Point
    
    init(startPoint: Point, endPoint: Point) {
        self.startPoint = startPoint
        self.endPoint = endPoint
    }
}

//Mark:- DrawingPad
//  This is just to make example more interesting
//  We are just printing the point on Console to make it simple
class DrawingPad {
    //Draw Single point, main drawing method
    func draw(point: Point) {
        print(".")
    }
    
    //Draw multiple points
    func draw(points: [Point]) {
        points.forEach { (point) in
            self.draw(point: point)
        }
    }
}

//Mark: LineSegmentToPointAdapter
//  This is responsible to generate all points exists on LineSegment
class LineSegmentToPointAdapter {
    var lineSegment: LineSegment
    init(lineSegment: LineSegment) {
        self.lineSegment = lineSegment
    }
    func points() -> Array<Point> {
        //To make things simple, without complex line drawing algorithms,
        //This will only work for points like below
        //(10,10) to (20,20)
        //(34,34) to (89,89)
        //(x,y) to (p,q) where y=x and q=p i.e. (x,x) to (p,p) just to make it simple for this demo
        
        var points: Array<Point> = []
        let zipXY = zip(
            (self.lineSegment.startPoint.x...self.lineSegment.endPoint.x),
            (self.lineSegment.startPoint.y...self.lineSegment.endPoint.y)
        )
        for (x,y) in zipXY {
            let newPoint = Point(x: x, y: y)
            points.append(newPoint)
        }
        return points
    }
    
}




func main(){
    let drawingPad = DrawingPad()
    
    //Remeber: (x,y) to (p,q) where y=x and q=p => (x,x) to (p,p) for our points logic to work
    
    //create lineSegment
    let startPoint = Point(x: 2, y: 2)
    let endPoint = Point(x: 10, y: 10)
    let lineSegment = LineSegment(startPoint: startPoint, endPoint: endPoint)
    
    //create adapter
    let adapter = LineSegmentToPointAdapter(lineSegment: lineSegment)
    
    //get points from adapter to draw
    let points = adapter.points()
    
    drawingPad.draw(points: points) //it will draw total 9 dots on console
}

//call main function to execute code
main()