darling-TextEdit/MultiplePageView.m

/*
     File: MultiplePageView.m
 Abstract: View which holds all the pages together in the multiple-page case.
 
  Version: 1.9
 
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 MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION
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 IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL
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 */

#import <Cocoa/Cocoa.h>
#import "MultiplePageView.h"
#import "TextEditMisc.h"

@implementation MultiplePageView

- (id)initWithFrame:(NSRect)rect {
    if ((self = [super initWithFrame:rect])) {
        numPages = 0;
        [self setLineColor:[NSColor lightGrayColor]];
        [self setMarginColor:[NSColor whiteColor]];
	/* This will set the frame to be whatever's appropriate... */
        [self setPrintInfo:[NSPrintInfo sharedPrintInfo]];
    }
    return self;
}

- (BOOL)isFlipped {
    return YES;
}

- (BOOL)isOpaque {
    return YES;
}

- (void)updateFrame {
    if ([self superview]) {
        NSRect rect = NSZeroRect;
        rect.size = [printInfo paperSize];
        if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
            rect.size.height = rect.size.height * numPages;
            if (numPages > 1) rect.size.height += [self pageSeparatorHeight] * (numPages - 1);
        } else {
            rect.size.width = rect.size.width * numPages;
            if (numPages > 1) rect.size.width += [self pageSeparatorHeight] * (numPages - 1);
        }
        rect.size = [self convertSize:rect.size toView:[self superview]];
        [self setFrame:rect];
    }
}

- (void)setPrintInfo:(NSPrintInfo *)anObject {
    if (printInfo != anObject) {
        [printInfo autorelease];
        printInfo = [anObject copyWithZone:[self zone]];
        [self updateFrame];
        [self setNeedsDisplay:YES];	/* Because the page size or margins might change (could optimize this) */
    }
}

- (NSPrintInfo *)printInfo {
    return printInfo;
}

- (void)setNumberOfPages:(NSUInteger)num {
    if (numPages != num) {
	NSRect oldFrame = [self frame];
        NSRect newFrame;
        numPages = num;
        [self updateFrame];
	newFrame = [self frame];
        if (newFrame.size.height > oldFrame.size.height) {
	    [self setNeedsDisplayInRect:NSMakeRect(oldFrame.origin.x, NSMaxY(oldFrame), oldFrame.size.width, NSMaxY(newFrame) - NSMaxY(oldFrame))];
        }
    }
}

- (NSUInteger)numberOfPages {
    return numPages;
}
    
- (CGFloat)pageSeparatorHeight {
    return 5.0;
}

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

- (NSSize)documentSizeInPage {
    return documentSizeForPrintInfo(printInfo);
}

- (NSRect)documentRectForPageNumber:(NSUInteger)pageNumber {	/* First page is page 0, of course! */
    NSRect rect = [self pageRectForPageNumber:pageNumber];
    rect.origin.x += [printInfo leftMargin] - defaultTextPadding();
    rect.origin.y += [printInfo topMargin];
    rect.size = [self documentSizeInPage];
    return rect;
}

- (NSRect)pageRectForPageNumber:(NSUInteger)pageNumber {
    NSRect rect;
    rect.size = [printInfo paperSize];
    rect.origin = [self frame].origin;

    if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
        rect.origin.y += ((rect.size.height + [self pageSeparatorHeight]) * pageNumber);
    } else {
        rect.origin.x += (NSWidth([self bounds]) - ((rect.size.width + [self pageSeparatorHeight]) * (pageNumber + 1)));
    }
    return rect;
}

/* For locations on the page separator right after a page, returns that page number.  Same for any locations on the empty (gray background) area to the side of a page. Will return 0 or numPages-1 for locations beyond the ends. Results are 0-based.
*/
- (NSUInteger)pageNumberForPoint:(NSPoint)loc {
    NSUInteger pageNumber;
    if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
        if (loc.y < 0) pageNumber = 0;
        else if (loc.y >= [self bounds].size.height) pageNumber = numPages - 1;
        else pageNumber = loc.y / ([printInfo paperSize].height + [self pageSeparatorHeight]);
    } else {
        if (loc.x < 0) pageNumber = numPages - 1;
        else if (loc.x >= [self bounds].size.width) pageNumber = 0;
        else pageNumber = (NSWidth([self bounds]) - loc.x) / ([printInfo paperSize].width + [self pageSeparatorHeight]);
    }
    return pageNumber;    
}

- (void)setLineColor:(NSColor *)color {
    if (color != lineColor) {
        [lineColor autorelease];
        lineColor = [color copyWithZone:[self zone]];
        [self setNeedsDisplay:YES];
    }
}

- (NSColor *)lineColor {
    return lineColor;
}

- (void)setMarginColor:(NSColor *)color {
    if (color != marginColor) {
        [marginColor autorelease];
        marginColor = [color copyWithZone:[self zone]];
        [self setNeedsDisplay:YES];
    }
}

- (NSColor *)marginColor {
    return marginColor;
}

- (void)setLayoutOrientation:(NSTextLayoutOrientation)orientation {
    if (orientation != layoutOrientation) {
        layoutOrientation = orientation;

        [self updateFrame];
    }
}

- (NSTextLayoutOrientation)layoutOrientation {
    return layoutOrientation;
}

- (void)drawRect:(NSRect)rect {
    if ([[NSGraphicsContext currentContext] isDrawingToScreen]) {
        NSSize paperSize = [printInfo paperSize];
        NSUInteger firstPage;
        NSUInteger lastPage;
        NSUInteger cnt;

        if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
            firstPage = NSMinY(rect) / (paperSize.height + [self pageSeparatorHeight]);
            lastPage = NSMaxY(rect) / (paperSize.height + [self pageSeparatorHeight]);
        } else {
            firstPage = numPages - (NSMaxX(rect) / (paperSize.width + [self pageSeparatorHeight]));
            lastPage = numPages - (NSMinX(rect) / (paperSize.width + [self pageSeparatorHeight]));
        }

        [marginColor set];
        NSRectFill(rect);

        [lineColor set];
        for (cnt = firstPage; cnt <= lastPage; cnt++) {
	    // Draw boundary around the page, making sure it doesn't overlap the document area in terms of pixels
	    NSRect docRect = NSInsetRect([self centerScanRect:[self documentRectForPageNumber:cnt]], -1.0, -1.0);
	    NSFrameRectWithWidth(docRect, 1.0);
        }

        if ([[self superview] isKindOfClass:[NSClipView class]]) {
            NSColor *backgroundColor = [(NSClipView *)[self superview] backgroundColor];
            [backgroundColor set];
            for (cnt = firstPage; cnt <= lastPage; cnt++) {
                NSRect pageRect = [self pageRectForPageNumber:cnt];
                NSRect separatorRect;
                if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
                    separatorRect = NSMakeRect(NSMinX(pageRect), NSMaxY(pageRect), NSWidth(pageRect), [self pageSeparatorHeight]);
                } else {
                    separatorRect = NSMakeRect(NSMaxX(pageRect), NSMinY(pageRect), [self pageSeparatorHeight], NSHeight(pageRect));
                }
                NSRectFill (separatorRect);
            }
        }
    }
}

/**** Smart magnification ****/

- (NSRect)rectForSmartMagnificationAtPoint:(NSPoint)location inRect:(NSRect)visibleRect {    
    NSRect result;
    NSUInteger pageNumber = [self pageNumberForPoint:location];
    NSRect documentRect = NSInsetRect([self documentRectForPageNumber:pageNumber], -3.0, -3.0);  // We use -3 to show a bit of the margins
    NSRect pageRect = [self pageRectForPageNumber:pageNumber];
    
    if (NSPointInRect(location, documentRect)) {        // Smart magnify on page contents; return the page contents rect
        result = documentRect;
    } else if (NSPointInRect(location, pageRect)) {     // Smart magnify on page margins; return the page rect (not including separator area)
        result = pageRect;
    } else {        // Smart magnify between pages, or the empty area beyond the side or bottom/top of the page; return the extended area for the page
        result = pageRect;
        if (NSTextLayoutOrientationHorizontal == layoutOrientation) {
            if (NSMaxX(visibleRect) > NSMaxX(pageRect)) result.size.width = NSMaxX(visibleRect);        // include area to the right of the paper
            if (pageNumber + 1 < numPages) result.size.height += [self pageSeparatorHeight];
            if (location.y > NSMaxY(result)) result.size.height = ceil(location.y - result.origin.y);   // extend the rect out to include location
        } else {
            if (NSMaxY(visibleRect) > NSMaxY(pageRect)) result.size.height = NSMaxY(visibleRect);       // include area below the paper
            if (pageNumber + 1 < numPages) result.size.width += [self pageSeparatorHeight];
            if (location.x > NSMaxX(result)) result.size.width = ceil(location.x - result.origin.x);    // extend the rect out to include location
        }
    }
    return result;
}

/**** Printing support... ****/

- (BOOL)knowsPageRange:(NSRangePointer)aRange {
    aRange->length = [self numberOfPages];
    return YES;
}

- (NSRect)rectForPage:(NSInteger)page {
    return [self documentRectForPageNumber:page-1];  /* Our page numbers start from 0; the kit's from 1 */
}

/* This method makes sure that we center the view on the page. By default, the text view "bleeds" into the margins by defaultTextPadding() as a way to provide padding around the editing area. If we don't do anything special, the text view appears at the margin, which causes the text to be offset on the page by defaultTextPadding(). This method makes sure the text is centered.
*/
- (NSPoint)locationOfPrintRect:(NSRect)rect {
    NSSize paperSize = [printInfo paperSize];
    return NSMakePoint((paperSize.width - rect.size.width) / 2.0, (paperSize.height - rect.size.height) / 2.0);
}

@end


NSSize documentSizeForPrintInfo(NSPrintInfo *printInfo) {
    NSSize paperSize = [printInfo paperSize];
    paperSize.width -= ([printInfo leftMargin] + [printInfo rightMargin]) - defaultTextPadding() * 2.0;
    paperSize.height -= ([printInfo topMargin] + [printInfo bottomMargin]);
    return paperSize;
}