Currently, `src/core/core.js` uses the `fromRef` method on an `Annotation` object to obtain the right annotation type object (such as `LinkAnnotation` or `TextAnnotation`). That method in turn uses a method `getConstructor` to find out which annotation type object must be returned.
Aside from the fact that there is currently a lot of code to achieve this, these methods should not be part of the base `Annotation` class at all. Creation of annotation object should be done by a factory (as also recommended by @yurydelendik at https://github.com/mozilla/pdf.js/pull/5218#issuecomment-52779659) that handles finding out the correct annotation type object and returning it. This patch implements this separation of concerns.
Doing this allows us to also simplify the code quite a bit and to make it more readable. Additionally, we are now able to get rid of the hardcoded array of supported annotation types. The factory takes care of checking the annotation types and falls back to returning the base annotation type (and issuing a warning, which the current code also does not do well) when an annotation type is unsupported.
I have manually tested this commit with 20 test PDFs with different annotation types, such as /Link, /Text, /Widget, /FileAttachment and /FreeText. All render identically before and after the patch, and unsupported annotation types are now properly indicated with a warning in the console.
The 'Version' field of the most recent document catalog, if present, is
intended to supersede the value in the file prologue.
This is significant for incrementally-built PDF documents and generators that
emit a low version in the prologue and later apply a format version based on
PDF features used, such as Apple's CoreGraphics/Quartz PDF backend.
Fixes the internal version variable, as well as the PDFFormatVersion reported
by the API and consumed by viewers.
Fixes two issues:
- #4456 : The first 100 bytes are often not unique as they can be
filled with standard PDF headers - so we use the first 200 KB instead.
(This may be overkill)
- Some documents we encountered have invalid xref ids, which were
always coming out as ‘0000000000000000’ - so we detect that and use the
MD5 instead.
The function `assertWllFormed` was doing nothing different than `assert` which is
available in the same namespace. Removing it will lighten the filesize - albeit
very slightly - and reduce complexity.
Added an "InteractiveAnnotation" class to homogenize the annotations' structure (highlighting) and user interactions (for now, used for text and link annotations).
Text annotations:
The appearance (AP) has priority over the icon (Name).
The popup extends horizontally (up to a limit) as well as vertically.
Reduced the title's font size.
The annotation's color (C) is used to color the popup's background.
On top of the mouseover show/hide behavior, a click on the icon will lock the annotation open (for mobile purposes). It can be closed with another click on either the icon or the popup.
An annotation printing is conditioned by its "print" bit
Unsupported annotations are not displayed at all.