The original `ProgressBar`-functionality is very old, and could thus do with some general clean-up.
In particular, while it currently accepts various options those have never really been used in either the default viewer or in any examples. The sort of "styling" that these options provided are *much better*, not to mention simpler, done directly with CSS rules.
As part of these changes, the "progress" is now updated using CSS variables rather than by directly modifying the `style` of DOM elements. This should hopefully simplify future changes to this code, see e.g. PR 14898.
Finally, this also fixes a couple of other small things in the "mobile viewer" example.
While zeroing the temporary `canvas` makes sense, manually clearing the canvas and its context doesn't really accomplish anything since those are tied to the scope of the method.
We need to wait for UI rendering to start *before* getting the CSS variable values, since otherwise the values will be `NaN`.
This is only an issue if the viewer is completely hidden during loading, e.g. in a `display: none` iframe-element.
When pre-processor blocks are being removed, since they don't apply to the current build target, we may currently end up with consecutive blank lines.
While this is obviously not a big issue, it's nonetheless undesirable and we can adjust the `writeLine` function to prevent that.
*This is a follow-up to PR 14886, which "broke" this.*
In addition to fixing the issue, using an Array and `join`-ing it at the end may also be a tiny bit more efficient than using a growing string.
*This patch can be tested, in the viewer, using the `annotation-fileattachment.pdf` document from the test-suite.*
It seems that the code to delay dispatching of the "attachmentsloaded"-event, when `attachmentsCount === 0`, is now effectively broken.[1]
Rather than only using an arbitrary timeout, the new code will instead wait for an "annotationlayerrendered"-event and only *fallback* to using a timeout.
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[1] The timing of the annotationLayer-rendering changed slightly in PR 14247, and the old code in `PDFAttachmentViewer` wasn't good enough to handle that.
If the computed background/foreground colors are identical, the `canvas` would be rendered mostly blank with only images visible. Hence it seems reasonable to also ignore the `pageColors`-option in this case.
Also, the patch tries to *briefly* outline the various cases in which we ignore the `pageColors`-option in a comment.
Given that the new API-option is an Object named `pageColors`, with `background`/`foreground` keys, it occurred to me that it'd be slightly more consistent if the options/preferences names fully reflected that.
An old shortcoming of the `preprocessCSS`-function is its complete lack of support for our "normal" defines, which makes it very difficult to have build-specific CSS rules. Recently we've started using specially crafted comments to remove CSS rules from the MOZCENTRAL build, but (ab)using the `preprocessCSS`-function in this way really doesn't feel great.
However, it turns out to be surprisingly simple to instead use the "regular" `preprocess`-function for the CSS files as well. The only special-handling that's still necessary is the helper-function for dealing with CSS-imports, but apart from that everything seems to just work.
One reason, as far as I can tell, for having a separate `preprocessCSS`-function was likely that we originally used *lots* of vendor-prefixed CSS rules in our CSS files. With improvements over the years, especially thanks to Autoprefixer and PostCSS, we've been able to remove *almost* all non-standard CSS rules and the need for special-casing the CSS parsing has mostly vanished.
*Please note:* As part of testing this patch I've diffed the output of `gulp generic`, `gulp mozcentral`, and `gulp chromium` against the `master`-branch to check that there was no obvious breakage.
These methods are completely unused in the Firefox PDF Viewer, and were only added to supplement the `PDFViewerApplication.{bindEvents, bindWindowEvents}`-methods since third-party implementations may apparently need to remove event listeners (see PR 8525).
However, in the MOZCENTRAL build that's just dead code and this patch reduces the size of the *built* `web/viewer.js`-file by `~3.5` kB.
*This patch can be tested, in the viewer, using the `annotation-fileattachment.pdf` document from the test-suite.*
Note how the `FileSpec`-implementation already uses `stringToPDFString` during the filename lookup, see cfac6fa511/src/core/file_spec.js (L70)
Hence there's no reason to repeat that again in the `FileAttachmentAnnotationElement`-constructor, and we can thus simplify the "fileattachmentannotation"-event handling a little bit.
This new CSS variable will allow us to simplify a couple of different viewer components, since we no longer need to use JavaScript-based hacks and can directly set the CSS rules instead. In particular:
- The `BaseViewer`-handling, used as part of the code that will center pages *vertically* in PresentationMode, can be simplified.
By using CSS to control the height of the "dummy"-page we avoid unnecessarily invalidating the scale-value, which can reduce *some* unneeded re-rendering while PresentationMode is active.
- The `SecondaryToolbar.#setMaxHeight`-method, and its associated parameters, are no longer necessary and can be completely removed.
Note that in order for things to work correctly in general, the new `--viewer-container-height` CSS variable must potentially be updated on any window-based "resize"-event (even when there's no zooming). While this is currently only done in the default viewer, that shouldn't be an issue since neither PresentationMode nor Toolbar-functionality is included in the "viewer components".
- Use Canvas & CanvasText color when they don't have their default value
as background and foreground colors.
- The colors used to draw (stroke/fill) in a pdf are replaced by the bg/fg
ones according to their luminance.
After recent changes, adding *basic* Spread mode support in PresentationMode has now become reasonably straightforward.
However, documents with *varying* page sizes are non-trivial to handle and would require re-writing (or at least re-factoring) a bunch of the zooming-code.
Hence this PR *purposely* only allow Spread modes to be used, in PresentationMode, for documents where all pages have exactly the same size. While this obviously isn't a fully complete solution, it will however cover the vast majority of all documents and should hopefully be deemed good enough for now.
In PR 14112 usage of this *internal* method was reduced, and it thus can't hurt to clean-up things a little bit more.
Note in particular that we can simplify the call-sites by directly passing in the already available `PDFPageView`-instance, since the `id`-property those contain can replace the previous `pageNumber`-parameter[1].
Given that the method name has always been prefixed with an underscore it was thus never intended to be "public", hence we can now enforce that with modern ECMAScript features.
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[1] There's already a bunch of other spots, throughout the viewer-code, where we assume that the `PDFPageView.id`-property contains proper page *numbers* (and not e.g. indices); note how we initialize the `PDFPageView`-instances in the `BaseViewer.setDocument`-method.
The current `lastModified`-getter, which only contains a time-stamp, is a fairly crude way of detecting if the stored data has actually been changed. In particular, when the `getRawValue`-method is used, the `lastModified`-getter doesn't cope with data being modified from the "outside".
To fix these issues[1], and to prevent any future bugs in this code, this patch introduces a new `AnnotationStorage.hash`-getter which computes a hash of the currently stored data. To simplify things this re-uses the existing `MurmurHash3_64`-implementation, which required moving that file into the `src/shared/`-folder, since its performance should be good enough here.
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[1] Given how the `AnnotationStorage.lastModified`-getter was used, this would have been limited to *printing* of forms.
- since resetForm function reset a field value a calculateNow is consequently triggered.
But the calculate callback can itself call resetForm, hence an infinite recursive loop.
So basically, prevent calculeNow to be triggered by itself.
- in Firefox, the letters entered in some fields were duplicated: "AaBb" instead of "AB".
It was mainly because beforeInput was triggering a Keystroke which was itself triggering
an input value update and then the input event was triggered.
So in order to avoid that, beforeInput calls preventDefault and then it's up to the JS to
handle the event.
- fields have a property valueAsString which returns the value as a string. In the
implementation it was wrongly used to store the formatted value of a field (2€ when the user
entered 2). So this patch implements correctly valueAsString.
- non-rendered fields can be updated in using JS but when they're, they must take some properties
in the annotationStorage. It was implemented for field values, but it wasn't for
display, colors, ...
- it fixes#14862 and #14705.
Given that we're (ab)using spread-modes in order to ensure that pages are centered *vertically* in PresentationMode, this re-factoring simplifies the code slightly.
Furthermore, in the event that we *possibly* want to try and support spread-modes in PresentationMode[1] this re-factoring will also prevent future duplication.
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[1] Note that I'm not particularly keen on doing that, since documents with varying page sizes will be annoying to handle.
Given that the `isNodeJS`-constant will, after PR 14858, *always* be `false` in non-GENERIC builds we can simplify a couple of `getDocument`-parameter default values slightly.
The old format, with inline `PDFJSDev`-checks, wasn't exactly a wonder of readability; which was my fault.
This first of all simplifies the file, since we no longer need dummy-classes and can instead *directly* define the actual classes.
Furthermore, and more importantly, this means that we no longer need to bundle this code in e.g. MOZCENTRAL-builds which reduces the size of *built* `pdf.js` file slightly.
Given that the `compileType3Glyph` function *returns* a function, see `drawOutline`, we'll thus keep the surrounding scope alive. Hence it shouldn't hurt to *explicitly* mark the temporary `Uint8Array`s, used during parsing, as no longer needed. Given the current `MAX_SIZE_TO_COMPILE`-value these `Uint8Array`s may be approximately two mega-bytes large *for every* Type3-glyph.
