/*

    File:       ReceiveServerController.m

    Contains:   Manages the receive server tab.

    Written by: DTS

    Copyright:  Copyright (c) 2009-2012 Apple Inc. All Rights Reserved.

    Disclaimer: IMPORTANT: This Apple software is supplied to you by Apple Inc.

                ("Apple") in consideration of your agreement to the following

                terms, and your use, installation, modification or

                redistribution of this Apple software constitutes acceptance of

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                non-exclusive license, under Apple's copyrights in this

                original Apple software (the "Apple Software"), to use,

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                without modifications, in source and/or binary forms; provided

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                without modifications, you must retain this notice and the

                following text and disclaimers in all such redistributions of

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                or logos of Apple Inc. may be used to endorse or promote

                products derived from the Apple Software without specific prior

                written permission from Apple.  Except as expressly stated in

                this notice, no other rights or licenses, express or implied,

                are granted by Apple herein, including but not limited to any

                patent rights that may be infringed by your derivative works or

                by other works in which the Apple Software may be incorporated.

                The Apple Software is provided by Apple on an "AS IS" basis. 

                APPLE MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING

                WITHOUT LIMITATION THE IMPLIED WARRANTIES OF NON-INFRINGEMENT,

                MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, REGARDING

                THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN

                COMBINATION WITH YOUR PRODUCTS.

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*/

#import "ReceiveServerController.h"

#import "NetworkManager.h"

#include <CFNetwork/CFNetwork.h>

#include <sys/socket.h>

#include <netinet/in.h>

#include <unistd.h>

@interface ReceiveServerController () <NSStreamDelegate, NSNetServiceDelegate>

// stuff for IB

@property (nonatomic, strong, readwrite) IBOutlet UIImageView *               imageView;

@property (nonatomic, strong, readwrite) IBOutlet UILabel *                   statusLabel;

@property (nonatomic, strong, readwrite) IBOutlet UIActivityIndicatorView *   activityIndicator;

@property (nonatomic, strong, readwrite) IBOutlet UIButton *                  startOrStopButton;

- (IBAction)startOrStopAction:(id)sender;

// private properties

@property (nonatomic, assign, readonly ) BOOL               isStarted;

@property (nonatomic, assign, readonly ) BOOL               isReceiving;

@property (nonatomic, strong, readwrite) NSNetService *     netService;

@property (nonatomic, assign, readwrite) CFSocketRef        listeningSocket;

@property (nonatomic, strong, readwrite) NSInputStream *    networkStream;

@property (nonatomic, strong, readwrite) NSOutputStream *   fileStream;

@property (nonatomic, copy,   readwrite) NSString *         filePath;

// forward declarations

- (void)stopServer:(NSString *)reason;

@end

@implementation ReceiveServerController

@synthesize netService      = _netService;

@synthesize networkStream   = _networkStream;

@synthesize listeningSocket = _listeningSocket;

@synthesize fileStream      = _fileStream;

@synthesize filePath        = _filePath;

@synthesize imageView         = _imageView;

@synthesize statusLabel       = _statusLabel;

@synthesize activityIndicator = _activityIndicator;

@synthesize startOrStopButton = _startOrStopButton;

#pragma mark * Status management

// These methods are used by the core transfer code to update the UI.

- (void)serverDidStartOnPort:(NSUInteger)port

{

    assert( (port != 0) && (port < 65536) );

    self.statusLabel.text = [NSString stringWithFormat:@"Started on port %zu", (size_t) port];

    [self.startOrStopButton setTitle:@"Stop" forState:UIControlStateNormal];

    self.tabBarItem.image = [UIImage imageNamed:@"receiveserverOn.png"];

}

- (void)serverDidStopWithReason:(NSString *)reason

{

    if (reason == nil) {

        reason = @"Stopped";

    }

    self.statusLabel.text = reason;

    [self.startOrStopButton setTitle:@"Start" forState:UIControlStateNormal];

    self.tabBarItem.image = [UIImage imageNamed:@"receiveserverOff.png"];

}

- (void)receiveDidStart

{

    self.statusLabel.text = @"Receiving";

    self.imageView.image = [UIImage imageNamed:@"NoImage.png"];

    [self.activityIndicator startAnimating];

    [[NetworkManager sharedInstance] didStartNetworkOperation];

}

- (void)updateStatus:(NSString *)statusString

{

    assert(statusString != nil);

    self.statusLabel.text = statusString;

}

- (void)receiveDidStopWithStatus:(NSString *)statusString

{

    if (statusString == nil) {

        assert(self.filePath != nil);

        self.imageView.image = [UIImage imageWithContentsOfFile:self.filePath];

        statusString = @"Receive succeeded";

    }

    self.statusLabel.text = statusString;

    [self.activityIndicator stopAnimating];

    [[NetworkManager sharedInstance] didStopNetworkOperation];

}

#pragma mark * Core transfer code

// This is the code that actually does the networking.

- (BOOL)isStarted

{

    return (self.netService != nil);

}

- (BOOL)isReceiving

{

    return (self.networkStream != nil);

}

- (void)startReceive:(int)fd

{

    CFReadStreamRef     readStream;

    assert(fd >= 0);

    assert(self.networkStream == nil);      // can't already be receiving

    assert(self.fileStream == nil);         // ditto

    assert(self.filePath == nil);           // ditto

    // Open a stream for the file we're going to receive into.

    self.filePath = [[NetworkManager sharedInstance] pathForTemporaryFileWithPrefix:@"Receive"];

    assert(self.filePath != nil);

    self.fileStream = [NSOutputStream outputStreamToFileAtPath:self.filePath append:NO];

    assert(self.fileStream != nil);

    [self.fileStream open];

    // Open a stream based on the existing socket file descriptor.  Then configure 

    // the stream for async operation.

    CFStreamCreatePairWithSocket(NULL, fd, &readStream, NULL);

    assert(readStream != NULL);

    self.networkStream = (__bridge NSInputStream *) readStream;

    CFRelease(readStream);

    [self.networkStream setProperty:(id)kCFBooleanTrue forKey:(NSString *)kCFStreamPropertyShouldCloseNativeSocket];

    self.networkStream.delegate = self;

    [self.networkStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

    [self.networkStream open];

    // Tell the UI we're receiving.

    [self receiveDidStart];

}

- (void)stopReceiveWithStatus:(NSString *)statusString

{

    if (self.networkStream != nil) {

        self.networkStream.delegate = nil;

        [self.networkStream removeFromRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

        [self.networkStream close];

        self.networkStream = nil;

    }

    if (self.fileStream != nil) {

        [self.fileStream close];

        self.fileStream = nil;

    }

    [self receiveDidStopWithStatus:statusString];

    self.filePath = nil;

}

- (void)stream:(NSStream *)aStream handleEvent:(NSStreamEvent)eventCode

    // An NSStream delegate callback that's called when events happen on our 

    // network stream.

{

    assert(aStream == self.networkStream);

    #pragma unused(aStream)

    switch (eventCode) {

        case NSStreamEventOpenCompleted: {

            [self updateStatus:@"Opened connection"];

        } break;

        case NSStreamEventHasBytesAvailable: {

            NSInteger       bytesRead;

            uint8_t         buffer[32768];

            [self updateStatus:@"Receiving"];

            // Pull some data off the network.

            bytesRead = [self.networkStream read:buffer maxLength:sizeof(buffer)];

            if (bytesRead == -1) {

                [self stopReceiveWithStatus:@"Network read error"];

            } else if (bytesRead == 0) {

                [self stopReceiveWithStatus:nil];

            } else {

                NSInteger   bytesWritten;

                NSInteger   bytesWrittenSoFar;

                // Write to the file.

                bytesWrittenSoFar = 0;

                do {

                    bytesWritten = [self.fileStream write:&buffer[bytesWrittenSoFar] maxLength:bytesRead - bytesWrittenSoFar];

                    assert(bytesWritten != 0);

                    if (bytesWritten == -1) {

                        [self stopReceiveWithStatus:@"File write error"];

                        break;

                    } else {

                        bytesWrittenSoFar += bytesWritten;

                    }

                } while (bytesWrittenSoFar != bytesRead);

            }

        } break;

        case NSStreamEventHasSpaceAvailable: {

            assert(NO);     // should never happen for the output stream

        } break;

        case NSStreamEventErrorOccurred: {

            [self stopReceiveWithStatus:@"Stream open error"];

        } break;

        case NSStreamEventEndEncountered: {

            // ignore

        } break;

        default: {

            assert(NO);

        } break;

    }

}

- (void)acceptConnection:(int)fd

{

    int     junk;

    // If we already have a connection, reject this new one.  This is one of the 

    // big simplifying assumptions in this code.  A real server should handle 

    // multiple simultaneous connections.

    if ( self.isReceiving ) {

        junk = close(fd);

        assert(junk == 0);

    } else {

        [self startReceive:fd];

    }

}

static void AcceptCallback(CFSocketRef s, CFSocketCallBackType type, CFDataRef address, const void *data, void *info)

    // Called by CFSocket when someone connects to our listening socket.  

    // This implementation just bounces the request up to Objective-C.

{

    ReceiveServerController *  obj;

    #pragma unused(type)

    assert(type == kCFSocketAcceptCallBack);

    #pragma unused(address)

    // assert(address == NULL);

    assert(data != NULL);

    obj = (__bridge ReceiveServerController *) info;

    assert(obj != nil);

    assert(s == obj->_listeningSocket);

    #pragma unused(s)

    [obj acceptConnection:*(int *)data];

}

- (void)netService:(NSNetService *)sender didNotPublish:(NSDictionary *)errorDict

    // A NSNetService delegate callback that's called if our Bonjour registration 

    // fails.  We respond by shutting down the server.

    //

    // This is another of the big simplifying assumptions in this sample. 

    // A real server would use the real name of the device for registrations, 

    // and handle automatically renaming the service on conflicts.  A real 

    // client would allow the user to browse for services.  To simplify things 

    // we just hard-wire the service name in the client and, in the server, fail 

    // if there's a service name conflict.

{

    #pragma unused(sender)

    assert(sender == self.netService);

    #pragma unused(errorDict)

    [self stopServer:@"Registration failed"];

}

- (void)startServer

{

    BOOL                success;

    int                 err;

    int                 fd;

    int                 junk;

    struct sockaddr_in  addr;

    NSUInteger          port;

    // Create a listening socket and use CFSocket to integrate it into our 

    // runloop.  We bind to port 0, which causes the kernel to give us 

    // any free port, then use getsockname to find out what port number we 

    // actually got.

    port = 0;

    fd = socket(AF_INET, SOCK_STREAM, 0);

    success = (fd != -1);

    if (success) {

        memset(&addr, 0, sizeof(addr));

        addr.sin_len    = sizeof(addr);

        addr.sin_family = AF_INET;

        addr.sin_port   = 0;

        addr.sin_addr.s_addr = INADDR_ANY;

        err = bind(fd, (const struct sockaddr *) &addr, sizeof(addr));

        success = (err == 0);

    }

    if (success) {

        err = listen(fd, 5);

        success = (err == 0);

    }

    if (success) {

        socklen_t   addrLen;

        addrLen = sizeof(addr);

        err = getsockname(fd, (struct sockaddr *) &addr, &addrLen);

        success = (err == 0);

        if (success) {

            assert(addrLen == sizeof(addr));

            port = ntohs(addr.sin_port);

        }

    }

    if (success) {

        CFSocketContext context = { 0, (__bridge void *) self, NULL, NULL, NULL };

        assert(self->_listeningSocket == NULL);

        self->_listeningSocket = CFSocketCreateWithNative(

            NULL, 

            fd, 

            kCFSocketAcceptCallBack, 

            AcceptCallback, 

            &context

        );

        success = (self->_listeningSocket != NULL);

        if (success) {

            CFRunLoopSourceRef  rls;

            fd = -1;        // listeningSocket is now responsible for closing fd

            rls = CFSocketCreateRunLoopSource(NULL, self.listeningSocket, 0);

            assert(rls != NULL);

            CFRunLoopAddSource(CFRunLoopGetCurrent(), rls, kCFRunLoopDefaultMode);

            CFRelease(rls);

        }

    }

    // Now register our service with Bonjour.  See the comments in -netService:didNotPublish: 

    // for more info about this simplifying assumption.

    if (success) {

        self.netService = [[NSNetService alloc] initWithDomain:@"local." type:@"_x-SNSUpload._tcp." name:@"Test" port:port];

        success = (self.netService != nil);

    }

    if (success) {

        self.netService.delegate = self;

        [self.netService publishWithOptions:NSNetServiceNoAutoRename];

        // continues in -netServiceDidPublish: or -netService:didNotPublish: ...

    }

    // Clean up after failure.

    if ( success ) {

        assert(port != 0);

        [self serverDidStartOnPort:port];

    } else {

        [self stopServer:@"Start failed"];

        if (fd != -1) {

            junk = close(fd);

            assert(junk == 0);

        }

    }

}

- (void)stopServer:(NSString *)reason

{

    if (self.isReceiving) {

        [self stopReceiveWithStatus:@"Cancelled"];

    }

    if (self.netService != nil) {

        [self.netService stop];

        self.netService = nil;

    }

    if (self.listeningSocket != NULL) {

        CFSocketInvalidate(self.listeningSocket);

        CFRelease(self->_listeningSocket);

        self->_listeningSocket = NULL;

    }

    [self serverDidStopWithReason:reason];

}

#pragma mark * Actions

- (IBAction)startOrStopAction:(id)sender

{

    #pragma unused(sender)

    if (self.isStarted) {

        [self stopServer:nil];

    } else {

        [self startServer];

    }

}

#pragma mark * View controller boilerplate

- (void)viewDidLoad

{

    [super viewDidLoad];

    assert(self.imageView != nil);

    assert(self.statusLabel != nil);

    assert(self.activityIndicator != nil);

    assert(self.startOrStopButton != nil);

    self.activityIndicator.hidden = YES;

    self.statusLabel.text = @"Tap Start to start the server";

}

- (void)viewDidUnload

{

    [super viewDidUnload];

    self.imageView = nil;

    self.statusLabel = nil;

    self.activityIndicator = nil;

    self.startOrStopButton = nil;

}

- (void)dealloc

{

    [self stopServer:nil];

}

@end