FlickrService

FlickrService.swift

import Foundation
import Moya
import SwiftyJSON

fileprivate enum FlickrAPI {
    case photosSearch(lat: Double, lng: Double)
}

extension FlickrAPI: TargetType {
    var baseURL: URL { return URL(string: "https://api.flickr.com/services/rest/")! }
    
    var path: String {
        switch self {
        case .photosSearch:
            return ""
        }
    }
    
    var method: Moya.Method {
        switch self {
        case .photosSearch:
            return .get
        }
    }
    
    var task: Task {
        switch self {
        case .photosSearch(let lat, let lng):
            let parameters: [String: Any] = ["method": "flickr.photos.search",
                                             "api_key": "c76689472c10fa2a42a414091cb50588",
                                             "format": "json",
                                             "nojsoncallback": "1",
                                             "extras": "url_l",
                                             "per_page": "5",
                                             "lat": lat,
                                             "lon": lng]
            return .requestParameters(parameters: parameters, encoding: URLEncoding.queryString)
        }
    }
    
    var sampleData: Data {
        switch self {
        case .photosSearch:
            return "{}".utf8Encoded
        }
    }
    
    var headers: [String: String]? {
        return ["Content-type": "application/json"]
    }
}

// MARK: - Helpers
fileprivate extension String {
    var urlEscaped: String {
        return addingPercentEncoding(withAllowedCharacters: .urlHostAllowed)!
    }
    
    var utf8Encoded: Data {
        return data(using: .utf8)!
    }
}

protocol FlickrServiceInterface {
    typealias GetPhotosHandler = ([String]?) -> Void
    
    func getPhotos(latitude: Double, longitude: Double, getPhotosHandler: GetPhotosHandler?)
}

final class FlickrService: FlickrServiceInterface {
    
    private let provider = MoyaProvider<FlickrAPI>()
    
    func getPhotos(latitude: Double, longitude:Double, getPhotosHandler: GetPhotosHandler?) {
        provider.request(.photosSearch(lat: latitude, lng: longitude)) { result in
            switch result {
            case let .failure(error):
                print("API Error \(error)")
            case let .success(response):
                if let filteredResponse = try? response.filterSuccessfulStatusCodes(), let json = try? JSON(data: filteredResponse.data) {
                    var photoURLs: [String]? = nil
                    if json["stat"].stringValue != "ok" {
                        print("API Error \(response.statusCode) - please check the request to \(response.request?.url?.absoluteString ?? "")")
                        print("Response was: \(json.debugDescription)")
                    } else {
                        let photosDict = json["photos"].dictionaryValue
                        let photoArray = photosDict["photo"]?.arrayValue
                        photoURLs = photoArray?.map({$0["url_l"].stringValue})
                    }
                    if let handler = getPhotosHandler {
                        handler(photoURLs)
                    }
                } else {
                    print("API Error \(response.statusCode) - please check the request to\(response.request?.url?.absoluteString ?? "")")
                    if let responseString = String(data: response.data, encoding: .utf8) {
                        print("Response was: \(responseString)")
                    }
                }
            }
        }
    }
}