FeaturedAppsController.swift

//
//  ViewController.swift
//  AppStore1
//
//  Created by Tiago Bastos on 03/08/2017.
//  Copyright © 2017 Tiago Bastos. All rights reserved.
//

import UIKit

class FeaturedAppsController: UICollectionViewController, UICollectionViewDelegateFlowLayout {
    
    private let cellId = "CellId"
    private let largeCellId = "LargeCellId"
    private let headerId = "headerId"
    
    var featuredApps: FeaturedApps?
    var appCategories: [AppCategory]?
    

    override func viewDidLoad() {
        super.viewDidLoad()
        
        navigationItem.title = "Featured Apps"
        
        AppCategory.fetchFeaturedApps { (featuredApps) -> () in
            self.featuredApps = featuredApps
            self.appCategories = featuredApps.appCategories
            self.collectionView?.reloadData()
        }
        
        collectionView?.backgroundColor = .white
        
        collectionView?.register(CategoryCell.self , forCellWithReuseIdentifier: cellId)
        collectionView?.register(LargeCategoryCell.self , forCellWithReuseIdentifier: largeCellId)
        
        collectionView?.register(Header.self, forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: headerId)
        
    }
    
    func showAppDetailForApp(app: App){
        let layout = UICollectionViewFlowLayout()
        let appDetailController = AppDetailController(collectionViewLayout: layout)
        appDetailController.app = app
        navigationController?.pushViewController(appDetailController, animated: true)
    }
    
    override func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
        
        let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind , withReuseIdentifier: headerId, for: indexPath) as! Header
        
        header.appCategory = featuredApps?.bannerCategory
        
        return header
    }
    
    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
        
        return CGSize(width: view.frame.width, height: 120)
    }
    
    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        
        if indexPath.item == 2 {
            let cell = collectionView.dequeueReusableCell(withReuseIdentifier: largeCellId, for: indexPath) as! LargeCategoryCell
            
            cell.appCategory = appCategories?[indexPath.item]
            cell.featureAppsController = self

            return cell
        }
        
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId , for: indexPath) as! CategoryCell
        cell.featureAppsController = self

        cell.appCategory = appCategories?[indexPath.item]
        
        return cell
    }

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        
        if indexPath.item == 2 {
            return CGSize(width: view.frame.width, height: 160)
        }
        
        return CGSize(width: view.frame.width, height: 230)
    }
    
    override func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {

        if let count = appCategories?.count {
            return count
        }
        
        return 0
    
    }
}

class Header: CategoryCell {
    
    let cellId = "bannerCellId"
    
    override func setupView() {
        appsCollectionView.dataSource = self
        appsCollectionView.delegate = self
        
        appsCollectionView.register(BannerCell.self, forCellWithReuseIdentifier: cellId)
        
        addSubview(appsCollectionView)
        addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": appsCollectionView]))
        addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": appsCollectionView]))
    }
    
    override func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, insetForSectionAt section: Int) -> UIEdgeInsets {
        return UIEdgeInsetsMake(0, 0, 0, 0)
    }
    
    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellId, for: indexPath) as! AppCell
        cell.app = appCategory?.apps?[indexPath.item]
        return cell
    }
    
    override func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        return CGSize(width: frame.width / 2 + 50, height: frame.height)
    }
    
    fileprivate class BannerCell: AppCell {
        fileprivate override func setupViews() {
            imageView.layer.borderColor = UIColor(white: 0.5, alpha: 0.5).cgColor
            imageView.layer.borderWidth = 0.5
            imageView.layer.cornerRadius = 0
            imageView.translatesAutoresizingMaskIntoConstraints = false
            addSubview(imageView)
            addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": imageView]))
            addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": imageView]))
        }
    }
    
}
class LargeCategoryCell: CategoryCell {
    
    private let largeAppCellId = "largeAppCellId"
    
    override func setupView() {
        super.setupView()
        
        appsCollectionView.register(LargeAppCell.self , forCellWithReuseIdentifier: largeAppCellId)
    }
    
    override func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
        return CGSize(width: 200, height: frame.height - 32)
    }
    
    override func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: largeAppCellId, for: indexPath) as! AppCell
        
        cell.app = appCategory?.apps?[indexPath.item]
        
        return cell
    }
    
    fileprivate class LargeAppCell: AppCell {
        fileprivate override func setupViews() {
            imageView.translatesAutoresizingMaskIntoConstraints = false
            addSubview(imageView)
            addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "H:|[v0]|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": imageView]))
            addConstraints(NSLayoutConstraint.constraints(withVisualFormat: "V:|-2-[v0]-14-|", options: NSLayoutFormatOptions(), metrics: nil, views: ["v0": imageView]))
        }
    }
}