[hayroob]

Finished my rewrite of the URL detection in the twitter page, it's a bit stricter about well formed urls than the old code, but less cruft slips through. I'm using regexkitlite to do all the pattern matching.

Scope my logic and see if it there's anything worth improving.

//
//  extractURL.m
//  KATG.com
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//  
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//  
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.

#import "extractURL.h"
#import "RegexKitLite.h"


@implementation extractURL

//*******************************************************
//* init
//* 
//* Set up object
//*******************************************************
- (id)init {
	return self;
}

//*******************************************************
//* makeURLList:(NSString *)stringWithURLs
//* 
//* Create an array of URL strings
//*******************************************************
- (id)makeURLList:(NSString *)stringWithURLs {
	NSMutableArray *urlList = [[NSMutableArray alloc] initWithCapacity:12];
	NSMutableDictionary *urlDict = [NSMutableDictionary dictionary];
	
	urlDict = [self makeURL:stringWithURLs];
	if (urlDict != nil) {
		NSString *protocolString = [urlDict objectForKey:@"protocol"];
		NSString *hostString = [urlDict objectForKey:@"host"];
		NSString *pathString = [urlDict objectForKey:@"path"];
		NSString *url = [protocolString stringByAppendingString:hostString]; 
		if (pathString != nil) {
			url = [url stringByAppendingString:pathString];
		}
		
		[urlList addObject:url];
	}
	
	int offset = 0;
	while (urlDict != nil) {
		offset += [[urlDict objectForKey:@"location"] intValue] + [[urlDict objectForKey:@"length"] intValue] - 1;
		int length = stringWithURLs.length - offset;
		urlDict = [self makeURL:[stringWithURLs substringWithRange:NSMakeRange( offset, length ) ]];		
		if (urlDict != nil) {
			NSString *protocolString = [urlDict objectForKey:@"protocol"];
			NSString *hostString = [urlDict objectForKey:@"host"];
			NSString *pathString = [urlDict objectForKey:@"path"];
			NSString *url = [protocolString stringByAppendingString:hostString]; 
			if (pathString != nil) {
				url = [url stringByAppendingString:pathString];
			}
			
			[urlList addObject:url];
		}
	}
	
	return urlList;
}

//*******************************************************
//* makeURL:(NSString *)searchString
//* 
//* Create an array of tweet user dictionaries
//*******************************************************
- (id)makeURL:(NSString *)searchString {
	NSString *regexString = @"\\b(https?://)(?:(\\S+?)(?::(\\S+?))?@)?([a-zA-Z0-9\\-.]+)(?::(\\d+))?((?:/[a-zA-Z0-9\\-._?,'+\\&%$=~*!():@\\\\]*)+)?";
	NSMutableDictionary *urlDictionary = [NSMutableDictionary dictionary];
	NSRange matchedRange = NSMakeRange(NSNotFound, 0UL); 
	
	if ([searchString isMatchedByRegex:regexString]) {
		matchedRange = [searchString rangeOfRegex:regexString];
		int Location = matchedRange.location;
		int Length = matchedRange.length;
		NSNumber *location = [[NSNumber alloc] initWithInt:Location];
		NSNumber *length = [[NSNumber alloc] initWithInt:Length];
		NSString *protocolString = [searchString stringByMatching:regexString capture:1L];
		NSString *hostString = [searchString stringByMatching:regexString capture:4L];
		NSString *pathString = [searchString stringByMatching:regexString capture:6L];
		
		regexString = @"\\.$|\\?$|\\!$";
		matchedRange = NSMakeRange(NSNotFound, 0UL);
		matchedRange = [pathString rangeOfRegex:regexString];
		if (matchedRange.location != NSNotFound) {
			pathString = [pathString substringWithRange:NSMakeRange(0, pathString.length - 1)];
		}
		
		if (location)       {[urlDictionary setObject:location forKey:@"location"];}
		if (length)         {[urlDictionary setObject:length forKey:@"length"];}
		if (protocolString) {[urlDictionary setObject:protocolString forKey:@"protocol"];} 
		if (hostString)     {[urlDictionary setObject:hostString forKey:@"host"];}
		if (pathString)     {[urlDictionary setObject:pathString forKey:@"path"];}
		NSLog(@"urlDictionary: %@", urlDictionary);
		
		return urlDictionary;
	} else {
		return nil;
	}
}

//*******************************************************
//* makeTWTList:(NSString *)stringWithTWTs
//* 
//* Extract, using regular expressions,
//* the first URL that occurs in a string
//* Results are compiled in an array
//*******************************************************

- (id)makeTWTList:(NSString *)stringWithTWTs {
	NSMutableArray *twtList = [[NSMutableArray alloc] initWithCapacity:12];
	NSMutableDictionary *twtDict = [NSMutableDictionary dictionary];
	
	twtDict = [self makeTwitterSearchURL:stringWithTWTs];
	if (twtDict != nil) {
		NSMutableDictionary *url = [NSMutableDictionary dictionary];
		
		[url setObject:[twtDict objectForKey:@"user"] forKey:@"user"];
		[url setObject:[twtDict objectForKey:@"url"] forKey:@"url"];
		
		[twtList addObject:url];
	}
	
	int offset = 0;
	while (twtDict != nil) {
		offset += [[twtDict objectForKey:@"location"] intValue] + [[twtDict objectForKey:@"length"] intValue] - 1;
		int length = stringWithTWTs.length - offset;
		twtDict = [self makeTwitterSearchURL:[stringWithTWTs substringWithRange:NSMakeRange( offset, length ) ]];		
		if (twtDict != nil) {
			NSMutableDictionary *url = [NSMutableDictionary dictionary];
			
			[url setObject:[twtDict objectForKey:@"user"] forKey:@"user"];
			[url setObject:[twtDict objectForKey:@"url"] forKey:@"url"];
			
			[twtList addObject:url];
		}
	}
	
	return twtList;
}

//*******************************************************
//* makeTwitterSearchURL:(NSString *)searchString
//* 
//* Extract, using regular expressions,
//* the first twitter user name that
//* occurs in a string
//* Results are compiled in a dictionary as
//* the the user name and the json library
//* URL
//*******************************************************
- (id)makeTwitterSearchURL:(NSString *)searchString {
	NSString *regexString = @"@([0-9a-zA-Z_]+)";
	NSMutableDictionary *urlDictionary = [NSMutableDictionary dictionary];
	NSRange matchedRange = NSMakeRange(NSNotFound, 0UL); 
	
	if ([searchString isMatchedByRegex:regexString]) {
		matchedRange = [searchString rangeOfRegex:regexString];
		int Location = matchedRange.location;
		int Length = matchedRange.length;
		NSNumber *location = [[NSNumber alloc] initWithInt:Location];
		NSNumber *length = [[NSNumber alloc] initWithInt:Length];
		NSString *twtUser = [searchString stringByMatching:regexString capture:1L];
		NSString *twtUserSearchUrl = @"http://search.twitter.com/search.json?q=from%3A";
		twtUserSearchUrl = [[twtUserSearchUrl stringByAppendingString:twtUser] stringByAppendingString:@"&rpp=10"];
		
		if (location)         {[urlDictionary setObject:location forKey:@"location"];}
		if (length)           {[urlDictionary setObject:length forKey:@"length"];}
		if (twtUser)          {[urlDictionary setObject:twtUser forKey:@"user"];} 
		if (twtUserSearchUrl) {[urlDictionary setObject:twtUserSearchUrl forKey:@"url"];} 

		NSLog(@"urlDictionary: %@", urlDictionary);
		
		return urlDictionary;
	} else {
		return nil;
	}
}

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

@end

The first thing I'm going to work on next, is adding flags to the methods to include/exclude location/length data for the data and then I can use that to figure where to draw buttons to make links/users clickable instead of using an intermediary view.