_MiscMergeIndexCommand.m

//
//  _MiscMergeIndexCommand.m
//
//	Written by Don Yacktman and Carl Lindberg
//
//	Copyright 2001-2004 by Don Yacktman and Carl Lindberg.
//	All rights reserved.
//
//      This notice may not be removed from this source code.
//
//	This header is included in the MiscKit by permission from the author
//	and its use is governed by the MiscKit license, found in the file
//	"License.rtf" in the MiscKit distribution.  Please refer to that file
//	for a list of all applicable permissions and restrictions.
//

#import "_MiscMergeIndexCommand.h"
#import "MiscMergeExpression.h"
#import <Foundation/NSArray.h>
#import <Foundation/NSString.h>

@implementation _MiscMergeIndexCommand

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

- (BOOL)parseFromScanner:(NSScanner *)aScanner template:(MiscMergeTemplate *)template
{
    [self eatKeyWord:@"index" fromScanner:aScanner isOptional:NO];
    arrayField = [[self getArgumentStringFromScanner:aScanner toEnd:NO quotes:&arrayQuote] retain];
    theIndex = [[self getPrimaryExpressionFromScanner:aScanner] retain];
    return YES;
}

- (MiscMergeCommandExitType)executeForMerge:(MiscMergeEngine *)aMerger
{
    id theArray = [aMerger valueForField:arrayField quoted:arrayQuote];

    if ( [theArray respondsToSelector:@selector(objectAtIndex:)] ) {
        int lookupIndex = [theIndex evaluateAsIntWithEngine:aMerger];

        if ( (lookupIndex >= 0) && (lookupIndex < [theArray count]) ) {
            [aMerger appendToOutput:[theArray objectAtIndex:lookupIndex]];
        }
    }
    else {
        [aMerger appendToOutput:theArray];
    }

    return MiscMergeCommandExitNormal;
}

@end