//

//  BackgroundLineView.swift

//  LineBackgroundView

//

//  Created by YouXianMing on 16/8/14.

//  Copyright © 2016年 YouXianMing. All rights reserved.

//

import UIKit

// MARK: Public class : BackgroundLineView

class BackgroundLineView: UIView {

    // MARK: Properties.

    /// Line width, default is 5.

    var lineWidth : CGFloat {

        get {return backgroundView.lineWidth}

        set(newVal) {

            backgroundView.lineWidth = newVal

            backgroundView.setNeedsDisplay()

        }

    }

    /// Line gap, default is 3.

    var lineGap : CGFloat {

        get {return backgroundView.lineGap}

        set(newVal) {

            backgroundView.lineGap = newVal

            backgroundView.setNeedsDisplay()

        }

    }

    /// Line color, default is grayColor.

    var lineColor : UIColor {

        get {return backgroundView.lineColor}

        set(newVal) {

            backgroundView.lineColor = newVal

            backgroundView.setNeedsDisplay()

        }

    }

    /// Rotate value, default is 0.

    var rotate : CGFloat {

        get {return backgroundView.rotate}

        set(newVal) {

            backgroundView.rotate = newVal

            backgroundView.setNeedsDisplay()

        }

    }

    convenience init(frame: CGRect, lineWidth : CGFloat, lineGap : CGFloat, lineColor : UIColor, rotate : CGFloat) {

        self.init(frame : frame)

        self.lineWidth = lineWidth

        self.lineGap   = lineGap

        self.lineColor = lineColor

        self.rotate    = rotate

    }

    // MARK: Override system method.

    override func layoutSubviews() {

        super.layoutSubviews()

        setupBackgroundView()

    }

    override init(frame: CGRect) {

        super.init(frame: frame)

        self.layer.masksToBounds = true

        self.addSubview(backgroundView)

    }

    required init?(coder aDecoder: NSCoder) {

        fatalError("init(coder:) has not been implemented")

    }

    // MARK: Private value & func.

    private let backgroundView = LineBackground(length: )

    private func setupBackgroundView() {

        let drawLength        = sqrt(self.bounds.size.width * self.bounds.size.width + self.bounds.size.height * self.bounds.size.height)

        backgroundView.frame  = CGRectMake(, , drawLength, drawLength)

        backgroundView.center = CGPointMake(self.bounds.size.width / 2.0, self.bounds.size.height / 2.0)

        backgroundView.setNeedsDisplay()

    }

}

// MARK: Private class : LineBackground

private class LineBackground : UIView {

    private var rotate    : CGFloat =

    private var lineWidth : CGFloat =

    private var lineGap   : CGFloat =

    private var lineColor : UIColor = UIColor.grayColor()

    override init(frame: CGRect) {

        super.init(frame: frame)

        self.backgroundColor = UIColor.clearColor()

    }

    required init?(coder aDecoder: NSCoder) {

        fatalError("init(coder:) has not been implemented")

    }

    convenience init(length : CGFloat) {

        self.init(frame : CGRectMake(, , length, length))

    }

    override func drawRect(rect: CGRect) {

        super.drawRect(rect)

        if self.bounds.size.width <=  || self.bounds.size.height <=  {

            return

        }

        let context      = UIGraphicsGetCurrentContext()

        let width        = self.bounds.size.width

        let height       = self.bounds.size.width

        let drawLength   = sqrt(width * width + height * height)

        let outerX       = (drawLength - width)  / 2.0

        let outerY       = (drawLength - height) / 2.0

        let tmpLineWidth = lineWidth <=  ?  : lineWidth

        let tmpLineGap   = lineGap   <=  ?  : lineGap

        var red   : CGFloat =

        var green : CGFloat =

        var blue  : CGFloat =

        var alpha : CGFloat = 

        CGContextTranslateCTM(context, 0.5 * drawLength, 0.5 * drawLength)

        CGContextRotateCTM(context, rotate)

        CGContextTranslateCTM(context, -0.5 * drawLength, -0.5 * drawLength)

        lineColor.getRed(&red, green: &green, blue: &blue, alpha: &alpha)

        CGContextSetRGBFillColor(context, red, green, blue, alpha)

        var currentX = -outerX

        while currentX < drawLength {

            CGContextAddRect(context, CGRectMake(currentX, -outerY, tmpLineWidth, drawLength))

            currentX += tmpLineWidth + tmpLineGap

        }

        CGContextFillPath(context)

    }

}

//

//  ViewController.swift

//  LineBackgroundView

//

//  Created by YouXianMing on 16/8/14.

//  Copyright © 2016年 YouXianMing. All rights reserved.

//

import UIKit

class ViewController: UIViewController {

    let tmpView = BackgroundLineView(frame: CGRectMake(, , , ), lineWidth: , lineGap: ,

                                     lineColor: UIColor.blackColor().colorWithAlphaComponent(0.045), rotate: CGFloat(M_PI_4))

    override func viewDidLoad() {

        super.viewDidLoad()

        tmpView.center = self.view.center

        self.view.addSubview(tmpView)

    }

}