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/*
 *  R.app : a Cocoa front end to: "R A Computer Language for Statistical Data Analysis"
 *  
 *  R.app Copyright notes:
 *                     Copyright (C) 2004-12  The R Foundation
 *                     written by Stefano M. Iacus and Simon Urbanek
 *
 *                  
 *  R Copyright notes:
 *                     Copyright (C) 1995-1996   Robert Gentleman and Ross Ihaka
 *                     Copyright (C) 1998-2001   The R Development Core Team
 *                     Copyright (C) 2002-2004   The R Foundation
 *
 *  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 2 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.
 *
 *  A copy of the GNU General Public License is available via WWW at
 *  http://www.gnu.org/copyleft/gpl.html.  You can also obtain it by
 *  writing to the Free Software Foundation, Inc., 59 Temple Place,
 *  Suite 330, Boston, MA  02111-1307  USA.
 *
 *  RScriptEditorLayoutManager.m
 *
 *  Created by Hans-J. Bibiko on 01/03/2012.
 *
 */

#import "RScriptEditorLayoutManager.h"
#import "RScriptEditorTypeSetter.h"
#import "RScriptEditorGlyphGenerator.h"
#import "RScriptEditorTextStorage.h"
#import "PreferenceKeys.h"

@implementation RScriptEditorLayoutManager

- (id)init
{

    self = [super init];
    
    if (nil == self) return nil;

    // Setup LineFoldingTypesetter
    RScriptEditorTypeSetter *typesetter = [[RScriptEditorTypeSetter alloc] init];
    [self setTypesetter:typesetter];
    [typesetter release];

    // Setup LineFoldingGlyphGenerator
    RScriptEditorGlyphGenerator *glyphGenerator = [[RScriptEditorGlyphGenerator alloc] init];
    [self setGlyphGenerator:glyphGenerator];
    [glyphGenerator release];

    [self setBackgroundLayoutEnabled:YES];

    return self;

}

- (void)drawGlyphsForGlyphRange:(NSRange)glyphsToShow atPoint:(NSPoint)origin
{
    // <SPEED>
    NSTextStorage *textStorage = [self textStorage];

    [(RScriptEditorTextStorage *)textStorage setLineFoldingEnabled:YES];
    [super drawGlyphsForGlyphRange:glyphsToShow atPoint:origin];
    [(RScriptEditorTextStorage *)textStorage setLineFoldingEnabled:NO];
}

- (void)textStorage:(NSTextStorage *)str edited:(NSUInteger)editedMask range:(NSRange)newCharRange changeInLength:(NSInteger)delta invalidatedRange:(NSRange)invalidatedCharRange
{

    NSUInteger length = [str length];
    NSNumber *value;
    NSRange effectiveRange, range;

    // it's at the end. check if the last char is in foldingAttributeName
    if ((invalidatedCharRange.location == length) && (invalidatedCharRange.location != 0)) { 
    value = [str attribute:foldingAttributeName atIndex:invalidatedCharRange.location - 1 effectiveRange:&effectiveRange];
        if (value && [value boolValue]) invalidatedCharRange = NSUnionRange(invalidatedCharRange, effectiveRange);
    }

    if (invalidatedCharRange.location < length) {
        NSString *string = [str string];
        NSUInteger start, end;

        if (delta > 0) {
            NSUInteger contentsEnd;
            [string getParagraphStart:NULL end:&end contentsEnd:&contentsEnd forRange:newCharRange];
            if ((contentsEnd != end) && (invalidatedCharRange.location > 0) 
                && (NSMaxRange(newCharRange) == end)) { 
                // there was para sep insertion. extend to both sides
                if (newCharRange.location <= invalidatedCharRange.location) {
                    invalidatedCharRange.length = (NSMaxRange(invalidatedCharRange) - (newCharRange.location - 1));
                    invalidatedCharRange.location = (newCharRange.location - 1);
                }

                if ((end < length) && (NSMaxRange(invalidatedCharRange) <= end)) {
                    invalidatedCharRange.length = ((end + 1) - invalidatedCharRange.location);
                }
            }
        }

        range = invalidatedCharRange;

        while ((range.location > 0) || (NSMaxRange(range) < length)) {
            [string getParagraphStart:&start end:&end contentsEnd:NULL forRange:range];
            range.location = start;
            range.length = (end - start);

            // Extend backward
            value = [str attribute:foldingAttributeName atIndex:range.location longestEffectiveRange:&effectiveRange inRange:NSMakeRange(0, range.location + 1)];
            if (value && [value boolValue] && (effectiveRange.location < range.location)) {
                range.length += (range.location - effectiveRange.location);
                range.location = effectiveRange.location;
            }

            // Extend forward
            if (NSMaxRange(range) < length) {
                value = [str attribute:foldingAttributeName atIndex:NSMaxRange(range) longestEffectiveRange:&effectiveRange inRange:NSMakeRange(NSMaxRange(range), length - NSMaxRange(range))];
                if (value && [value boolValue] && (NSMaxRange(effectiveRange) > NSMaxRange(range))) {
                    range.length = NSMaxRange(effectiveRange) - range.location;
                }
            }

            if (NSEqualRanges(range, invalidatedCharRange)) break;
            invalidatedCharRange = range;
        }
    }

    [super textStorage:str edited:editedMask range:newCharRange changeInLength:delta invalidatedRange:invalidatedCharRange];

}

@end