//
//  BJGOptionInterpreter.m
//  Escape
//
//  Created by Brent Gulanowski on 11/26/05.
//  Copyright 2005 Bored Astronaut Software. All rights reserved.
//


#import "BJGOptionInterpreter.h"

#import <unistd.h>


@interface BJGOptionInterpreter (BJGOptionInterpreter_private)
+(NSArray *)parseOptions:(NSString *)opts;
@end


@implementation BJGOptionInterpreter


/** inheritance tree overrides **/
#pragma mark NSObject
#if 0  /* remove the guards as necessary */
+(void)initialize {
}
#endif

-(id)init {
	[self release];
	return nil;
}


/** new methods **/
#pragma mark BJGOptionInterpreter

-(id)initWithOptionList:(NSString *)optList rawArguments:(NSArray *)args {

	NSArray *allOpts = [BJGOptionInterpreter parseOptions:optList];

	NSMutableArray *opts = [NSMutableArray array];
	NSMutableArray *optsArgs = [NSMutableArray array]; /* "opt_s_Args" plural: array of arrays of args */
	NSMutableArray *otherArgs = [NSMutableArray array];
	
	NSEnumerator *argsEnumerator;
	id arg;
	id nextArg;
	
	if(nil == args) {
		args = [[NSProcessInfo processInfo] arguments];
	}
	argsEnumerator = [args objectEnumerator];

	executable = [argsEnumerator nextObject];
	arg = [argsEnumerator nextObject];
	nextArg = [argsEnumerator nextObject];

	while(arg) {
		
		id option;
		id optionWithArgs;
		
		/* If the current arg doesn't look like an option... */
		if('-' != [arg characterAtIndex:0] /*|| 2 != [arg length]*/) {
			 /* it isn't ... */
			[otherArgs addObject:arg];
			/* ... and none of the rest are either */
			if(nextArg) {
				do {
					[otherArgs addObject:nextArg];
				} while(nextArg = [argsEnumerator nextObject]);
			}
			break;
		}

		/* It may look like an option, but we have to confirm it's legitimate */
		option = [arg substringWithRange:NSMakeRange(1,1)];

		optionWithArgs = [option stringByAppendingString:@":"];
		
		/* a legit option without arguments */
		if(YES == [allOpts containsObject:option]) {
			int argLength = [arg length];
			int pos = 2;
			if(NO == [opts containsObject:option]) {
				[opts addObject:option];
				[optsArgs addObject:[NSArray array]];
			}
			while(argLength - pos > 0 && YES == [allOpts containsObject:option]) {
				option = [arg substringWithRange:NSMakeRange(pos++,1)];
				if(NO == [opts containsObject:option]) {
					[opts addObject:option];
					[optsArgs addObject:[NSArray array]];
				}
			}
		}
		
		else if(YES == [allOpts containsObject:optionWithArgs]) {
			/* a legit option with arguments */
			
			NSMutableArray *optionArgs = [NSMutableArray array]; /* array of args */
			
			if([arg length] > 2) {
				[optionArgs addObject:[arg substringFromIndex:2]];
			}
			
			/* collect the arguments */
			while(nextArg && '-' != [nextArg characterAtIndex:0]) {
				[optionArgs addObject:nextArg];
				nextArg = [argsEnumerator nextObject];
			}
			/* opts that require args and don't have 'em mean an error */
			if(0 == [optionArgs count]) {
				[self release];
				self = nil;
				break;
			}
			/* have we seen this option already? if so, coalesce arguments */
			if(YES == [opts containsObject:option]) {
				int originalOptionIndex = [opts indexOfObject:option];
				[optionArgs addObjectsFromArray:[optsArgs objectAtIndex:originalOptionIndex]];
				[optsArgs replaceObjectAtIndex:originalOptionIndex withObject:optionArgs];
			}
			else {
				[opts addObject:option];				
				[optsArgs addObject:optionArgs];
			}
		}
		
		/* bad option; release self and return nothing; app should print usage message */
		else {
			[self release];
			self = nil;
			break;
		}
		
		arg = nextArg;
		nextArg = [argsEnumerator nextObject];
	}
	
	/* if we got here and didn't commit suicide, collect a nice arg dictionary */
	if(self) {
		optionList = [optList retain];
		arguments = [[NSArray arrayWithArray:otherArgs] retain];
		options = [[NSDictionary dictionaryWithObjects:optsArgs forKeys:opts] retain];
	}

	return self;
}

-(NSString *)optionList {
	return [[optionList copy] autorelease];
}

-(NSString *)executable {
	return [[executable copy] autorelease];
}

-(NSDictionary *)options {
	return [[options copy] autorelease];
}

-(NSArray *)arguments {
	return [[arguments copy] autorelease];
}


#pragma mark BJGOptionInterpreter_private
+(NSArray *)parseOptions:(NSString *)opts {
	int i;
	int length =[opts length];
	NSMutableArray *options = [NSMutableArray arrayWithCapacity:length];
	NSCharacterSet *lower = [NSCharacterSet lowercaseLetterCharacterSet];
	
	for(i = 0; i<length; i++) {
		char current = [opts characterAtIndex:i];
		char next;
		
		if(i < length - 1) {
			next = [opts characterAtIndex:i+1];
		}
		else {
			next = '\0';
		}
		
		if(NO == [lower characterIsMember:current]) {
			continue;
		}
		
		NSString *option = [NSString stringWithCString:&current length:1];
		if(':' == next) {
			option = [option stringByAppendingString:@":"];
			i++;
		}
		
		if(NO == [options containsObject:option]) {
			[options addObject:option];
		}
	}
	
	return [NSArray arrayWithArray:options];
}

@end