ViewController.swift

//
//  ViewController.swift
//  Example
//
//  Created by Hirohisa Kawasaki on 2/12/15.
//  Copyright (c) 2015 Hirohisa Kawasaki. All rights reserved.
//

import UIKit
import Union
import QuartzCore

class CollectionViewCell: UICollectionViewCell {
    @IBOutlet weak var imageView: UIImageView! {
        didSet {
            imageView.contentMode = .ScaleAspectFill
            imageView.autoresizingMask = [.FlexibleWidth, .FlexibleHeight]
            imageView.clipsToBounds = true
            imageView.layer.mask = CAShapeLayer()
        }
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        if let mask = imageView.layer.mask as? CAShapeLayer {
            mask.path = circlePathWithRect(bounds).CGPath
        }
    }

    func circlePathWithRect(frame: CGRect) -> UIBezierPath {
        let center = CGPoint(x: CGRectGetWidth(frame)/2, y: CGRectGetHeight(frame)/2)
        let path = UIBezierPath(arcCenter: center, radius: CGRectGetHeight(frame)/2, startAngle: 0, endAngle: 360, clockwise: true)
        return path
    }
}


class ViewController: UICollectionViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        edgesForExtendedLayout = .None
        title = "Oranges"

        let layout = UICollectionViewFlowLayout()
        layout.itemSize = CGSize(width: CGRectGetWidth(collectionView!.frame), height: 200)
        collectionView?.collectionViewLayout = layout
    }

    override func collectionView(collectionView: UICollectionView, didSelectItemAtIndexPath indexPath: NSIndexPath) {
        if let cell = collectionView.cellForItemAtIndexPath(indexPath) as? CollectionViewCell {
            let center = collectionView.convertPoint(cell.center, toView: view)

            let viewController = ArticleViewController(imageView: cell.imageView, center: center)

            navigationController?.delegate = self
            navigationController?.pushViewController(viewController, animated: true)
        }
    }

    override func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 10
    }

    override func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCellWithReuseIdentifier("CollectionViewCell", forIndexPath: indexPath) as! CollectionViewCell

        cell.imageView.image = UIImage(named: "orange")

        return cell
    }
}

extension ViewController: UINavigationControllerDelegate {
    func navigationController(navigationController: UINavigationController, animationControllerForOperation operation: UINavigationControllerOperation, fromViewController fromVC: UIViewController, toViewController toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {

        return Union.Navigator.animate()
    }

    func navigationController(navigationController: UINavigationController, interactionControllerForAnimationController animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? {

        return nil
    }
}