//

//  Created by Lennart Stolz on 03.07.15.

//  Copyright (c) 2016 Lennart Stolz. All rights reserved.

//

import Foundation

/// Function to create the lstolz.com webiste.

func createWebsite(withFactory factory: HTMLFactory ) throws {

    // This is the part where I should be polite.

    let greeting = factory.element(tag: "h1", content: "Hello Visitor" )

    print (greeting)

    let subline = factory.element(tag: "h2" , content: "Welcome to my website")

    print (subline)

    

    // Not sure if I'm an attention-seeker or just a self-publicist.

    let about = factory.element(tag: "h2" , content: "About me")

    print (about)

    

    let firstName = "Lennart"

    let lastName  = "Stolz"

    let aboutContent = factory.element(tag: "p", content: "I'm \ (firstName) \ (lastName)")

    print (aboutContent)

    

    

    // I'm just getting older and better. (Neal Schon)

    let dateFormatter = DateFormatter()

    dateFormatter.dateFormat = "dd.MM.y"

    guard let dateOfBirth = dateFormatter. date(from: "20.03.1989") else {

        throw HTMLFactory.Errors .invalidDate

    }

    

    let now = Date()

    let calendar = Calendar.current

    guard let age = calendar.dateComponents ([.year], from: dateOfBirth, to: now). year else {

        throw HTMLFactory.Errors .invalidDate

    }

    print (factory.element(tag: "p" , content: "I'm \( age) years old."))

    // Stop here before getting a shaggy dog story.

}

/// A tiny factory to provide html elements.

class HTMLFactory {

    /**

     Method to create an html element with opening and closing tag for a given content.

     - Parameters:

        - tag:      The html tag which should be used for this element.

        - content:  The text which should be displayed within the html element.

     - Returns: The aggregated html element.

     */

    func element(tag: String, content: String ) -> String {

        return "<\(tag )>\(content )</\(tag )>"

    }

    enum Errors: Error {

        case invalidDate

    }

}

let factory = HTMLFactory ()

try createWebsite(withFactory: factory)