// Alamofire.swift
//
// Copyright (c) 2014–2015 Alamofire Software Foundation (http://alamofire.org/)
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

import Foundation

extension Manager {
    private enum Uploadable {
        case Data(NSURLRequest, NSData)
        case File(NSURLRequest, NSURL)
        case Stream(NSURLRequest, NSInputStream)
    }
    
    private func upload(uploadable: Uploadable) -> Request {
        var uploadTask: NSURLSessionUploadTask!
        var HTTPBodyStream: NSInputStream?
        
        switch uploadable {
        case .Data(let request, let data):
            dispatch_sync(queue) {
                uploadTask = self.session.uploadTaskWithRequest(request, fromData: data)
            }
        case .File(let request, let fileURL):
            dispatch_sync(queue) {
                uploadTask = self.session.uploadTaskWithRequest(request, fromFile: fileURL)
            }
        case .Stream(let request, var stream):
            dispatch_sync(queue) {
                uploadTask = self.session.uploadTaskWithStreamedRequest(request)
            }
            HTTPBodyStream = stream
        }
        
        let request = Request(session: session, task: uploadTask)
        if HTTPBodyStream != nil {
            request.delegate.taskNeedNewBodyStream = { _, _ in
                return HTTPBodyStream
            }
        }
        delegate[request.delegate.task] = request.delegate
        
        if startRequestsImmediately {
            request.resume()
        }
        
        return request
    }
    
    // MARK: File
    
    /**
        Creates a request for uploading a file to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: URLRequest The URL request
        :param: file The file to upload
        
        :returns: The created upload request.
    */
    public func upload(URLRequest: URLRequestConvertible, file: NSURL) -> Request {
        return upload(.File(URLRequest.URLRequest, file))
    }
    
    /**
        Creates a request for uploading a file to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: method The HTTP method.
        :param: URLString The URL string.
        :param: file The file to upload
        
        :returns: The created upload request.
    */
    public func upload(method: Method, _ URLString: URLStringConvertible, file: NSURL) -> Request {
        return upload(URLRequest(method, URLString), file: file)
    }
    
    // MARK: Data
    
    /**
        Creates a request for uploading data to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: URLRequest The URL request
        :param: data The data to upload
        
        :returns: The created upload request.
    */
    public func upload(URLRequest: URLRequestConvertible, data: NSData) -> Request {
        return upload(.Data(URLRequest.URLRequest, data))
    }
    
    /**
        Creates a request for uploading data to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: method The HTTP method.
        :param: URLString The URL string.
        :param: data The data to upload
        
        :returns: The created upload request.
    */
    public func upload(method: Method, _ URLString: URLStringConvertible, data: NSData) -> Request {
        return upload(URLRequest(method, URLString), data: data)
    }
    
    // MARK: Stream
    
    /**
        Creates a request for uploading a stream to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: URLRequest The URL request
        :param: stream The stream to upload
        
        :returns: The created upload request.
    */
    public func upload(URLRequest: URLRequestConvertible, stream: NSInputStream) -> Request {
        return upload(.Stream(URLRequest.URLRequest, stream))
    }
    
    /**
        Creates a request for uploading a stream to the specified URL request.
        
        If `startRequestsImmediately` is `true`, the request will have `resume()` called before being returned.
        
        :param: method The HTTP method.
        :param: URLString The URL string.
        :param: stream The stream to upload.
        
        :returns: The created upload request.
    */
    public func upload(method: Method, _ URLString: URLStringConvertible, stream: NSInputStream) -> Request {
        return upload(URLRequest(method, URLString), stream: stream)
    }
}

// MARK: -

extension Request {
    
    // MARK: - UploadTaskDelegate
    
    class UploadTaskDelegate: DataTaskDelegate {
        var uploadTask: NSURLSessionUploadTask! { return task as! NSURLSessionUploadTask }
        var uploadProgress: ((Int64, Int64, Int64) -> Void)!
        
        // MARK: - NSURLSessionTaskDelegate
        
        func URLSession(session: NSURLSession!, task: NSURLSessionTask!, didSendBodyData bytesSent: Int64, totalBytesSent: Int64, totalBytesExpectedToSend: Int64) {
            progress.totalUnitCount = totalBytesExpectedToSend
            progress.completedUnitCount = totalBytesSent
            
            uploadProgress?(bytesSent, totalBytesSent, totalBytesExpectedToSend)
        }
    }
}