BadgeAPI.swift

//
//  BadgeAPI.swift
//  Badges
//
//  Created by Charles Kang on 6/15/16.
//  Copyright © 2016 Charles Kang. All rights reserved.
//

import Foundation
import SwiftyJSON

public func main(function: Void -> Void) {
    dispatch_async(dispatch_get_main_queue(), function)
}
public func background(function: Void -> Void) {
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_BACKGROUND, 0), function)
}
enum Result<T> {
    case success(T)
    case failure(ErrorType)
}

class BadgeAPI {
    
    public func fetch(completion: Result<[[String: String]]> -> Void) {
        let jsonURL = "http://www.khanacademy.org/api/v1/badges"
        background {
            if let url = NSURL(string: jsonURL) {
                if let data = try? NSData(contentsOfURL: url, options: []) {
                    let json = JSON(data: data)
                    let badges = self.parseBadgeJSON(json)
                    completion(.success(badges))
                }
            }
        }
    }
    
    public func parseBadgeJSON(json: JSON) -> [[String: String]]
    {
        var objects = [[String: String]]()
        
        for (_, result) in json {
            let title = result["description"].stringValue
            let smallIcon = result["icons"]["small"].stringValue
            let category = result["badge_category"].stringValue
            let points = result["points"].stringValue
            
            let obj = ["title": title, "icon": smallIcon, "category": category, "points": points]
            objects.append(obj)
        }
        return objects
    }
}