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@interface DownloaderViewController : UIViewController  {
NSMutableData *theData;
UIAlertView *downloadAlert;
NSString *urlString;
NSString *nameString;
NSString *watchString;
UIAlertView *dialog;
BOOL alertBool;
int downloadedLength;
int downloadLength;
int downloadedSec;
IBOutlet UIProgressView *progressViews;
IBOutlet UILabel *Message;
IBOutlet UILabel *Messages;
NSTimer *downloadCheckTimer;
NSFileHandle *file1;   
NSString *filename;
}
@property (nonatomic, retain) NSMutableData *theData;
@property (nonatomic, retain) NSFileHandle *file1;
@property (nonatomic, retain) IBOutlet UIWebView *Home;
@property (nonatomic, retain) NSString *urlString;
@property (nonatomic, retain) NSString *nameString;
-(IBAction)downloadButton;
@end

@implementation DownloaderViewController
@synthesize theData, file1, Home, urlString, nameString;

-(IBAction)downloadButton {
        [Home loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"http://iphonedeveloperhelp.info/AppleLogo.png"]]];
        [Home setDelegate:self];
        alertBool = YES;
}

- (BOOL)webView:(UIWebView*)webView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType {
        NSLog(@"shouldStartLoadWithRequest");
       
        if (alertBool == YES) {
               
                NSURL *url = request.URL;
                //urlString = [[NSString alloc] init];
                self.urlString = url.absoluteString;   
                self.nameString = url.absoluteString.lastPathComponent;
               
               
                if ([urlString hasSuffix:@".png"])
                {      
                        [Home stopLoading];
                        NSLog(@"Supported file type found");
                       
                        dialog = [[UIAlertView alloc] initWithTitle:@"Options" message:nil delegate:self cancelButtonTitle:@"Cancel" otherButtonTitles:@"Download", nil];
                        [dialog show];
                        [dialog release];
                }
                else {
                       
                }
        }
        else {
                alertBool = YES;
        }
       
       
        return YES;
}
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
        if (buttonIndex != [alertView cancelButtonIndex]){     
                if (buttonIndex == 0) {
                        //Cancel
                }
                else if (buttonIndex == 1) {
                        // Download Episode
                        alertBool = NO;
                        [dialog dismissWithClickedButtonIndex:0 animated:YES];
                        [self saveFileAtURL:[NSURL URLWithString:urlString]];
                        self.navigationItem.hidesBackButton = YES;
                }
        }
}

- (void)saveFileAtURL:(NSURL *)theUrl {
       
        NSURLRequest *theRequest = [NSURLRequest requestWithURL:theUrl];
       
        NSFileManager *manager = [NSFileManager defaultManager];
       
        NSString *docDir = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
       
        filename = [[NSString alloc] initWithFormat:@"%@/%@", docDir, nameString];
        [manager createFileAtPath:filename contents:nil attributes:nil];
        file1 = [[NSFileHandle fileHandleForWritingAtPath:filename] retain];
       
        // create the connection with the request and start loading the data
        NSURLConnection *theConnection = [[[NSURLConnection alloc] initWithRequest:theRequest delegate:self] retain];
        if (theConnection)
        {              
                NSMutableData *receivedData = [[NSMutableData data] retain];
                self.theData = receivedData;
                [receivedData release];
        }
        else
        {
                // inform the user that the download could not be made
                NSLog(@"Error");
        }
}

- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSHTTPURLResponse *)response {    
    // this method is called when the server has determined that it        
        // has enough information to create the NSURLResponse
    // it can be called multiple times, for example in the case of a
        // redirect, so each time we reset the data.
        // receivedData is declared as a method instance elsewhere
        [self.theData setLength:0];
        NSLog(@"Server answered");
        downloadCheckTimer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(downloadCheck) userInfo:nil repeats:YES];
        downloadLength = [[[response allHeaderFields] objectForKey:@"Content-Length"] intValue];
}

#define ONE_MB 1024
#define TWO_AND_A_HALF_MB 1*ONE_MB

- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data {
        Message.text = [NSString stringWithFormat:@"%@",[NSString stringWithFormat:@"%@", nameString]];
        [self.theData appendData:data];
       
       
        if(theData.length > TWO_AND_A_HALF_MB && file1!=nil)
        {
                [file1 writeData:self.theData];
                self.theData = [NSMutableData data];
        }
       
        downloadedLength += [data length];
        [progressViews setProgress:(float)downloadedLength/(float)downloadLength];
       
}

- (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error {
       
        // release the connection, and the data object
        [connection release];
        // receivedData is declared as a method instance elsewhere
       
        [self.theData release];
        [file1 closeFile];
       
        // inform the user
        NSLog(@"Connection failed! Error – %@ %@",
          [error localizedDescription],
          [[error userInfo] objectForKey:NSErrorFailingURLStringKey]);
}

- (void)connectionDidFinishLoading:(NSURLConnection *)connection {
    // do something with the data
       
    // receivedData is declared as a method instance elsewhere
    //NSLog(@"Succeeded! Received %d bytes of data",[receivedData length]);
               
        //int ran = random() % 1000000;
       
        Message.text = [NSString stringWithFormat:@"%@",[NSString stringWithFormat:@"%@", nameString]];
        file1 = [NSFileHandle fileHandleForUpdatingAtPath:filename];
        [file1 closeFile];
       
    // release the connection, and the data object
        //[receivedData release];
        // Auto dismiss after 3 seconds
        [self performSelector:@selector(performDismiss) withObject:nil afterDelay:3.0f];
    [connection release];
}
- (void) performDismiss {
        [progressViews setProgress:0.0];
        downloadLength = 0;
        downloadedLength = 0;
        Messages.text = @"0KB of 0KB";
        Message.text = @"Saved!";
        self.navigationItem.hidesBackButton = NO;
}

- (NSString *)stringWithBytes:(int)theBytes {
        double bytes = (double)theBytes;
        NSString *type = @"Bytes";
        if (bytes>1024.00) {
                type = @"KB";
                bytes = bytes/1024.00;
                if (bytes>1024.00) {
                        type = @"MB";
                        bytes = bytes/1024.00;
                        if (bytes>1024.00) {
                                type = @"GB";
                                bytes = bytes/1024.00;
                        }
                }
        }
        return [NSString stringWithFormat:@"%.2f %@", bytes, type];
}

- (NSString *)stringWithSeconds:(int)time {
        int seconds = time%60;
        time = time/60;
        int minutes = time%60;
        time = time/60;
        int hours = time%24;
    int days = time/24;
        NSString *string;
        if (days!=0) {
                string = [NSString stringWithFormat:@"%d:%02d:%02d:%02d", days, hours, minutes, seconds];
        } else if (hours!=0) {
                string = [NSString stringWithFormat:@"%d:%02d:%02d", hours, minutes, seconds];
        } else {
                string = [NSString stringWithFormat:@"%02d:%02d", minutes, seconds];
        }
        return string;
}

- (void)downloadCheck {
        [Messages setText:[NSString stringWithFormat:@"%@ of %@", [self stringWithBytes:downloadedLength], [self stringWithBytes:downloadLength]]];
}

- (void)dealloc {
[super dealloc];
}

@end