RequestController.swift

import Foundation

class RequestController: NSObject {

    typealias SuccessBock = ([Any]) -> ()
    typealias ErrorBlock = (NSError) -> ()
    typealias RequestResponseTuple = (con: NSURLConnection, success: SuccessBock?, error: ErrorBlock?)

    var baseURL: String
    private var currentActiveRequests: Dictionary<Int, RequestResponseTuple>

    class var sharedInstance: RequestController {
        struct Singleton {
            static let instance = RequestController(baseURL: "http://localhost:8080/Woingenau")
        }
        return Singleton.instance
    }

    init(baseURL: String) {
        self.baseURL = baseURL
        self.currentActiveRequests = [:]
    }

    func performHttpRequest(method: HTTPRequestMethod, path: String?, parameter:Dictionary<String, String>,
        success:SuccessBock?, error:ErrorBlock?) -> Int {
            var url = NSURL(string: baseURL.stringByAppendingPathComponent((path != nil) ? path! : ""))
            var request = NSURLRequest(URL: url!, cachePolicy: NSURLRequestCachePolicy.ReloadIgnoringLocalCacheData, timeoutInterval: 20.0)
            var con = NSURLConnection(request: request, delegate: self, startImmediately: true)
            var requestId = newRequestId()
            currentActiveRequests[requestId] = RequestResponseTuple(con, success, error)
            return requestId;
    }

    func cancelRequest(requestId: Int) {
        if (currentActiveRequests[requestId] != nil) {
            currentActiveRequests[requestId]!.con.cancel()
            removeRequestFromActiveRequestsDictionary(requestId)
        }
    }

    func removeRequestFromActiveRequestsDictionary(requestId: Int) {
        currentActiveRequests.removeValueForKey(requestId)
    }

    func newRequestId() -> Int {
        var requestId: Int?
        if (currentActiveRequests.count <= Int.max) {
            requestId = currentActiveRequests.count
        } else {
            requestId = -1
            do {
                requestId!++
            } while (currentActiveRequests[requestId!] != nil)
        }
        return requestId!
    }

    func requestIdForNSURLConnection(con: NSURLConnection) -> Int? {
        var requestId: Int? = nil
        if (!currentActiveRequests.isEmpty) {
            var requestIds = currentActiveRequests.keys.array
            var counter = 0
            do {
                if (currentActiveRequests[requestIds[counter]]!.con === con) {
                    requestId = requestIds[counter]
                }
            } while (counter < currentActiveRequests.count && requestId != nil)
        }
        return requestId
    }

    func finishRequestWithSuccess(connection: NSURLConnection, response: NSURLResponse) {
        var requestId = requestIdForNSURLConnection(connection)
        println("\(response)")
        currentActiveRequests[requestId!]!.success!([])
        removeRequestFromActiveRequestsDictionary(requestId!)
    }

    func finishRequestWithError(connection: NSURLConnection, didFailWithError error: NSError) {
        var requestId = requestIdForNSURLConnection(connection)
        println("\(error)")
        currentActiveRequests[requestId!]!.error!(error)
        removeRequestFromActiveRequestsDictionary(requestId!)
    }

}

extension RequestController: NSURLConnectionDataDelegate {

    func connection(connection: NSURLConnection, didReceiveResponse response: NSURLResponse) {
        finishRequestWithSuccess(connection, response: response)
    }

}

extension RequestController: NSURLConnectionDelegate {

    func connection(connection: NSURLConnection, didFailWithError error: NSError) {
        finishRequestWithError(connection, didFailWithError: error)
    }

}