/* 
        NSTextAttachment.h
        Copyright (c) 1994-2012, Apple Inc.
        All rights reserved.

        Classes to represent text attachments.

        NSTextAttachment is used to represent text attachments. When inline, text attachments appear as the value of the NSAttachmentAttributeName attached to the special character NSAttachmentCharacter.

        NSTextAttachment uses an object obeying the NSTextAttachmentCell protocol to get input from the user and to display an image.

        NSTextAttachmentCell is a simple subclass of NSCell which provides the NSTextAttachment protocol.
*/

#import <Foundation/NSObject.h>
#import <AppKit/NSCell.h>
#import <AppKit/NSAttributedString.h>

@class NSFileWrapper;
@class NSLayoutManager;
@class NSTextAttachment;
@class NSTextContainer;

enum {
    NSAttachmentCharacter = 0xfffc  // Replacement character is used for attachments
};

/* These are the only methods required of cells in text attachments... The default NSCell class implements most of these; the NSTextAttachmentCell class is a subclass which implements all and provides some additional functionality.
 */
@protocol NSTextAttachmentCell <NSObject>
- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView;
- (BOOL)wantsToTrackMouse;
- (void)highlight:(BOOL)flag withFrame:(NSRect)cellFrame inView:(NSView *)controlView;
- (BOOL)trackMouse:(NSEvent *)theEvent inRect:(NSRect)cellFrame ofView:(NSView *)controlView untilMouseUp:(BOOL)flag;
- (NSSize)cellSize;
- (NSPoint)cellBaselineOffset;
- (void)setAttachment:(NSTextAttachment *)anObject;
- (NSTextAttachment *)attachment;

// Sophisticated cells should implement these in addition to the simpler methods, above.  The class NSTextAttachmentCell implements them to simply call the simpler methods; more complex conformers should implement the simpler methods to call these.
- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView characterIndex:(NSUInteger)charIndex;
- (void)drawWithFrame:(NSRect)cellFrame inView:(NSView *)controlView characterIndex:(NSUInteger)charIndex layoutManager:(NSLayoutManager *)layoutManager;
- (BOOL)wantsToTrackMouseForEvent:(NSEvent *)theEvent inRect:(NSRect)cellFrame ofView:(NSView *)controlView atCharacterIndex:(NSUInteger)charIndex;
- (BOOL)trackMouse:(NSEvent *)theEvent inRect:(NSRect)cellFrame ofView:(NSView *)controlView atCharacterIndex:(NSUInteger)charIndex untilMouseUp:(BOOL)flag;
- (NSRect)cellFrameForTextContainer:(NSTextContainer *)textContainer proposedLineFragment:(NSRect)lineFrag glyphPosition:(NSPoint)position characterIndex:(NSUInteger)charIndex;
@end

/* Simple class to provide basic attachment cell functionality. By default this class causes NSTextView to send out delegate messages when the attachment is clicked on or dragged.
 */
@interface NSTextAttachmentCell : NSCell <NSTextAttachmentCell> {
    /*All instance variables are private*/
    NSTextAttachment *_attachment;
}
@end


@interface NSTextAttachment : NSObject <NSCoding> {
    /*All instance variables are private*/
    NSFileWrapper *_fileWrapper;
    id <NSTextAttachmentCell>_cell;
    struct {
        unsigned int cellWasExplicitlySet:1;
        unsigned int ignoresOrientation:1;
        unsigned int :30;
    } _flags;
}

/* Designated initializer.
 */
- (id)initWithFileWrapper:(NSFileWrapper *)fileWrapper;

/* The fileWrapper is the meat of most types of attachment.  It can be set or queried with these methods.  An NSTextAttachment usually has a fileWrapper.  setFileWrapper does not update the attachment's cell in any way.
 */
- (void)setFileWrapper:(NSFileWrapper *)fileWrapper;
- (NSFileWrapper *)fileWrapper;

/* The cell which handles user interaction. By default an instance of NSTextAttachmentCell is used.
 */
- (id <NSTextAttachmentCell>)attachmentCell;
- (void)setAttachmentCell:(id <NSTextAttachmentCell>)cell;

@end


/* Convenience for creating an attributed string with an attachment.
 */
@interface NSAttributedString (NSAttributedStringAttachmentConveniences)

+ (NSAttributedString *)attributedStringWithAttachment:(NSTextAttachment *)attachment;

@end

@interface NSMutableAttributedString (NSMutableAttributedStringAttachmentConveniences)

- (void)updateAttachmentsFromPath:(NSString *)path;

@end