InstagramShare.m

#import "InstagramShare.h"

void _handshake() 
{
    [[InstagramShare sharedInstance] handshake];
}

void _postToInstagram(const char * message, const char * imagePath)
{
    NSString *m = [NSString stringWithUTF8String:message];
    NSString *i = [NSString stringWithUTF8String:imagePath];
    [[InstagramShare sharedInstance] postToInstagram:m WithImage:i];
}

@implementation InstagramShare

@synthesize dic;

static InstagramShare *sharedInstance = nil;
+(InstagramShare*)sharedInstance {
    if( !sharedInstance )
        sharedInstance = [[InstagramShare alloc] init];
    
    return sharedInstance;
}


-(id)init 
{
    if (self = [super init]) 
    {
        nativeWindow = [UIApplication sharedApplication].keyWindow;
    }
    
    return self;
}

-(void)handshake 
{
    NSLog(@"Handshake completed!");
}

-(void)postToInstagram:(NSString*)message WithImage:(NSString*)imagePath;
{
    NSURL *appURL = [NSURL URLWithString:@"instagram://app"];
    if([[UIApplication sharedApplication] canOpenURL:appURL])
    {
        // Image
        UIImage *image = [UIImage imageWithContentsOfFile:imagePath];
        
        // Post
        [UIImageJPEGRepresentation(image, 1.0) writeToFile:[self photoFilePath] atomically:YES];
        NSURL *fileURL = [NSURL fileURLWithPath:[self photoFilePath]];
        
        self.dic = [UIDocumentInteractionController interactionControllerWithURL:fileURL];
        self.dic.UTI = @"com.instagram.exclusivegram";
        self.dic.delegate = self;
        if (message)
            self.dic.annotation = [NSDictionary dictionaryWithObject:message forKey:@"InstagramCaption"];
        
        [self.dic presentOpenInMenuFromRect:CGRectZero inView:nativeWindow.rootViewController.view animated:YES];
    }
    else
    {
        NSLog(@"Instagram not installed!");
    }
}

-(NSString*)photoFilePath 
{
    return [NSString stringWithFormat:@"%@/%@",[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"], @"tempinstgramphoto.igo"];
}

-(UIDocumentInteractionController*)setupControllerWithURL:(NSURL*)fileURL usingDelegate:(id<UIDocumentInteractionControllerDelegate>)interactionDelegate 
{
    UIDocumentInteractionController *interactionController = [UIDocumentInteractionController interactionControllerWithURL:fileURL];
    interactionController.delegate = interactionDelegate;
    return interactionController;
}

@end