//  Copyright © 2017 Schibsted. All rights reserved.

import Layout
import UIKit

final class ExamplesViewController: UIViewController, LayoutLoading, UITabBarControllerDelegate {
    private var selectedTab = 0

    override func viewDidLoad() {
        super.viewDidLoad()

        // Swift 3.x compatibility
        #if swift(>=4.2)
            let foregroundColorKey = NSAttributedString.Key.foregroundColor
        #elseif swift(>=4)
            let foregroundColorKey = NSAttributedStringKey.foregroundColor
        #else
            let foregroundColorKey = NSForegroundColorAttributeName
        #endif

        loadLayout(
            named: "Examples.xml",
            constants: [
                // Used in boxes, table and collection examples
                "colors": [
                    "red": UIColor(hexString: "#f66"),
                    "orange": UIColor(hexString: "#fa7"),
                    "blue": UIColor(hexString: "#09f"),
                    "green": UIColor(hexString: "#0f9"),
                    "pink": UIColor(hexString: "#fcc"),
                ],
                // Used in text example
                "attributedString": NSAttributedString(
                    string: "attributed string",
                    attributes: [foregroundColorKey: UIColor.red]
                ),
                "uppercased": { (args: [Any]) throws -> Any in
                    guard let string = args.first as? String else {
                        throw LayoutError.message("uppercased() function expects a String argument")
                    }
                    return string.uppercased()
                },
            ]
        )
    }

    func layoutDidLoad(_ layoutNode: LayoutNode) {
        guard let tabBarController = layoutNode.viewController as? UITabBarController else {
            return
        }

        tabBarController.selectedIndex = selectedTab
        tabBarController.delegate = self
    }

    func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
        guard let index = tabBarController.viewControllers?.index(of: viewController) else {
            return
        }
        selectedTab = index
    }
}