Now that it's possible to change the font-size, this placeholder string feels a little bit long (especially for larger font-sizes).
Given that Editing is not enabled/released yet, I hope that it should be fine to update this without changing the l10n-id.
This replaces the boolean `annotationEditorEnabled` option/preference with a "proper" `annotationEditorMode` one. This way it's not only possible for the user to control if Editing is enabled/disabled, but also which *specific* Editing-mode should become enabled upon PDF document load.
Given that Editing is not enabled/released yet, I cannot imagine that changing the name and type of the option/preference should be an issue.
Similar to other recent patches, see e.g. PR 15057, we don't want to add these kind of `id`s to DOM-elements since they shouldn't become "linkable" through the URL hash.
*Please note:* This patch can be tested, in the viewer, with e.g. `bug1737260.pdf` from the test-suite.
- As in the annotation layer, use percent instead of pixels as unit;
- handle the rotation of the editor layer in allowing editing when rotation
angle is not zero;
- the different editors are rotated counterclockwise in order to be usable
when the main page is itself rotated;
- add support for saving/printing rotated editors.
Given that printing is triggered *synchronously* in browsers, it's thus possible for scripting (in PDF documents) to modify the Annotation-data while printing is currently ongoing.
To work-around that we add a new printing-specific `AnnotationStorage`, where the serializable data is *frozen* upon initialization, which the viewer can thus create/utilize during printing.
For encrypted PDF documents without the required permissions set, this patch adds support for disabling of Annotation-editing. However, please note that it also requires that the `pdfjs.enablePermissions` preference is set to `true` (since PDF document permissions could be seen as user hostile).[1]
As I started looking at the issue, it soon became clear that *only* trying to fix the issue without slightly re-factor the surrounding code would be somewhat difficult.
The following is an overview of the changes in this patch; sorry about the size/scope of this!
- Use a new `AnnotationEditorUIManager`-instance *for each* PDF document opened in the GENERIC viewer, to prevent user-added Annotations from "leaking" from one document into the next.
- Re-factor the `BaseViewer.#initializePermissions`-method, to simplify handling of temporarily disabled modes (e.g. for both Annotation-rendering and Annotation-editing).
- When editing is enabled, let the Editor-buttons be `disabled` until the document has loaded. This way we avoid the buttons becoming clickable temporarily, for PDF documents that use permissions.
- Slightly re-factor how the Editor-buttons are shown/hidden in the viewer, and reset the toolbar-state when a new PDF document is opened.
- Flip the order of the Editor-buttons and the pre-exising toolbarButtons in the "toolbarViewerRight"-div. (To help reduce the size, a little bit, for the PR that adds new Editor-toolbars.)
- Enable editing by default in the development viewer, i.e. `gulp server`, since having to (repeatedly) do that manually becomes annoying after a while.
- Finally, support disabling of editing when `pdfjs.enablePermissions` is set; fixes issue 15049.
---
[1] Either manually with `about:config`, or using e.g. a [Group Policy](https://github.com/mozilla/policy-templates).
- each annotation has its coordinates/dimensions expressed in percentage,
hence it's correctly positioned whatever the scale factor is;
- the font sizes are expressed in percentage too and the main font size
is scaled thanks a css var (--scale-factor);
- the rotation is now applied on the div annotationLayer;
- this patch improve the rendering of some strings where the glyph spacing
was not correct (it's a Firefox bug);
- it helps to simplify the code and it should slightly improve the update of
page (on zoom or rotation).
We want to avoid adding regular `id`s to Annotation-elements, since that means that they become "linkable" through the URL hash in a way that's not supported/intended. This could end up clashing with "named destinations", and that could easily lead to bugs; see issue 11499 and PR 11503 for some context.
Rather than using `id`s, we'll instead use a *custom* `data-element-id` attribute such that it's still possible to access the Annotation-elements directly.
Unfortunately these changes required updating most of the integration-tests, and to reduce the amount of repeated code a couple of helper functions were added.
This option is not used, nor has it ever been used, in the *built-in* Firefox PDF Viewer. Hence we can define it only for the environments where it makes sense instead.
This should really have been done as part of PR 12470, since it's now possible to directly set the `defaultUrl`-option without having to fallback to `var`-usage.
- Right now, we must select the tool, then click to select a page and
click to start drawing and it's a bit painful;
- so just create a new ink editor when we're hovering a page without one.
Given that the SVG back-end is not defined anywhere except in GENERIC builds, we can remove a little bit of unnecessary code in e.g. the Firefox PDF Viewer.
Apparently the ESLint rule added in PR 15031 wasn't able to catch all cases that can be converted, which is probably not all that surprising given how some of these call-sites look.
- Use `Element.prepend()` to insert nodes before all other ones in the element, rather than using `firstChild` with `insertBefore`-calls; see https://developer.mozilla.org/en-US/docs/Web/API/Element/prepend
- Fix one *incorrect* `insertBefore` call, in the AnnotationLayer-code.
Initially the patch simply changed that to an `Element.before()`-call, however that broke one of the integration-tests. It turns out that the `index` may try to access a non-existent select-child, which triggers undefined behaviour; note the warning in https://developer.mozilla.org/en-US/docs/Web/API/Node/insertBefore#parameters
The update in https://bugzilla.mozilla.org/show_bug.cgi?id=1773794 failed, because the `editorNone` icon is identical to a pre-existing one. Given that all of the editor-icons are simply placeholders for now, we can just make a tiny change to the SVG-paths to prevent these kind of problems.
- Approximate the drawn curve by a set of Bezier curves in using
js code from https://github.com/soswow/fit-curves.
The code has been slightly modified in order to make the linter
happy.
Because of a capitalization error, the MIME type wasn't actually being set correctly. However, please note that downloading of font files still worked correctly which is probably why this has gone unnoticed since 2014.
Given the differences between XFA documents and "normal" PDF documents, we don't support editing of the former ones. Hence, when a XFA-document is opened, we temporarily disable the editor-buttons.
- Ensure that the modified-warning won't be displayed, when navigating away from the viewer, if the user has added custom Annotations and then *removed all* of them.
- Ensure that the *initial* editor-buttons state, i.e. the `toggled`-class, is correctly displayed in the toolbar when then viewer loads.
- Tweak the CSS-classes for the editor-buttons, such that they use the correct focus/hover-rules (similar to the sidebar-buttons).
- Remove a no longer accurate comment from the `BaseViewer.annotationEditorMode`-setter.
- Address a couple of *smaller* outstanding review comments, including some re-formatting changes, from PR 14976.
In PR 14710 we only included the JavaScript-part of the polyfill, however we probably need to include the CSS as well to reduce the risk of problems in older browsers.
With the recent CSS-related improvements in the `preprocess`-function we could probably have included this conditionally in the `viewer.css` file. However, considering that the `<dialog>` polyfill-code is only invoked when actually needed it seemed most appropriate/correct to lazy-load the polyfill-CSS as well.
- right now we're using the font size from the pdf itself but we use an other font
in the annotation layer. So this size doesn't really make sense and leads to bad
rendering (see pdf in #14928);
- use a sans-serif font for the fields containing text (fix issue #14736);
- remove useless padding in text-based fields (fix issue #14301);
- text fields allow/disallow scrolling bars (see bit 24 in Ff entry), so use this
value to hide/show scrollbars in annotation layer.
- it aims to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1771477;
- hangul contains some syllables which are decomposed when using NFD, hence
the text must be correctly shifted in case it contains some of them.
Currently, when range-requests and/or streaming are not supported or for documents opened from `data`-URLs, we'll manually set the `contentDispositionFilename` (assuming it exists and is valid) from the `onOpenWithData`-callback in `PDFViewerApplication.initPassiveLoading`.
However, because of a small oversight in `PDFViewerApplication._initializeMetadata`, this *cached* `contentDispositionFilename` would be ignored and we'd only attempt to use the one returned by `PDFDocumentProxy.getMetadata` in the API (which in the cases outlined above will always be empty).
Also, to ensure that the document properties dialog always displays the *correct* fileName we'll now lookup it using the same exact method as in the viewer itself (via a new callback-function).
With the exception of `isThumbnailViewVisible`, these getters are completely unused. Generally speaking, using the `visibleView`-getter directly works just as well and seems (at least to me) to be overall preferable considering how our classes are usually implemented.
Currently, when non-standard `pageColors` are specified, the thumbnails will look inconsistent depending on how they're created.
The thumbnails that are created by downsizing the *page* canvases will obviously use the `pageColors` as intended, however the thumbnails which are rendered *directly* will always use the default colors.
Over time, as we've been introducing JavaScript code to modify CSS variables, we've been adding shorthand properties to various classes to reduce unnecessary repetition when accessing the document-styles.
Rather than repeating this in multiple places, it seems overall simpler to just introduce a constant and re-use that throughout the viewer instead.
After the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=1757771, that simplified the MOZCENTRAL downloading code, the `ChromeActions.download`-method will no longer invoke the `sendResponse`-callback.
Hence it should no longer be necessary for the `DownloadManager`, in the MOZCENTRAL viewer, to use `FirefoxCom.requestAsync` since no response is ever provided.[1] For the allocated BlobURLs, they should (hopefully) be released when navigating away from the viewer.
---
[1] Note that that was *already* the case, for one of the previous code-paths in the `ChromeActions.download`-method.
After the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=1757771, that simplified the MOZCENTRAL downloading code, the `sourceEventType` is now completely unused and should thus be removed (in my opinion).
Furthermore, with these changes, we also no longer need a *separate* internal "save"-event and can instead just use the older "download"-event everywhere.
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.
*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.
---
[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.
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.
---
[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.
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.
---
[1] Note that I'm not particularly keen on doing that, since documents with varying page sizes will be annoying to handle.
There's no point in having these variables defined (implicitly) as `undefined` in e.g. the Firefox PDF Viewer.
By defining them with `var` and using ESList ignores, rather than `let`, we can move them into the relevant pre-processor block instead. Note that since the entire viewer-code is placed, by Webpack, in a top-level closure these variables will thus *not* become globally accessible.
Given that `webViewerOpenFileViaURL` only has a single call-site, and also isn't a particularly large/complex function, it doesn't seem necessary for this to be a separate function and hence it's simply inlined instead.
Also, changes the "no valid build-target was set"-case to throw unconditionally since the only way that it could ever be hit is if there are bugs in the `gulpfile`-code.
Currently we're using *both* ids and classes when specifying the button icons, which seems completely unnecessary and only serves to bloat the CSS code.
In general you always need to be careful about CSS specificity, but in these cases that should not actually be a problem.
Also, while not a button, this patch makes a similar simplification for the `pageNumber`-input.
Note how in the `viewer.html` file we're specifying class names for most buttons, despite that not really being necessary. First of all, in many cases those class names are *identical* to the element-ids. Secondly, looking through the CSS rules they are only ever used when specifying button icons.
All-in-all, we should be able to simplify the HTML-code and use the element-ids in the CSS rules instead. Obviously ids have a higher CSS specificity than classes, but given how the old classes were being used that shouldn't be a problem here.
Also, the patch generalizes the styling for buttons (e.g. `viewBookmark`) that are *actually* link-elements.
Finally, while slightly unrelated, this patch also removes a little bit of duplication when specifying the border for `toolbarField`s.
Searching through all of the files in the `web/`-folder has no *other* hits for the "textButton" string. Hence it's clear that there are no DOM elements actually using this class, and it's thus dead code.
This re-factors the various toolbar separators to *explicitly* specify both their dimensions and margins. Also, for the `horizontalToolbarSeparator`-class we can just set the `background-color` rather than using `border-top`.
Note that the `splitToolbarButtonSeparator`-class currently sets a number of unnecessary CSS rules, since as mentioned by the Firefox Devtools both the `display`- and `z-index`-properties are being ignored because `float` is used.
Finally, there's also no need to set a `z-index` for some of the `:hover`-rules. It's possible that this *was* necessary before the re-design, since the buttons had borders then.
Note how both of the openFile-buttons are always hidden during viewer initialization in the MOZCENTRAL build, i.e. the *built-in* Firefox PDF Viewer. Despite that we still include HTML, CSS, and JavaScript code for these buttons in the build.
This patch *reduces* the size of the `gulp mozcentral` output by `1679` bytes, which isn't a lot but still cannot hurt.
These rules became unnecessary with PR 7697, over five years ago, since printing is now done from a `printContainer`-element rather than "directly" using the viewer.
Note how the *entire* `outerContainer`, which contains all of the DOM elements that were being manually hidden, is now being hidden during printing. Furthermore, note also how the print-canvases/images and their containers are using custom CSS-classes[1] rather than re-using the ones from the viewer.
---
[1] See the `printedPage` respectively `xfaPrintedPage` classes.
Rather than modifying the leading/trailing `margin` on the actual toolbar buttons, to achieve appropriate spacing at the left/right edges of the toolbar(s), it seems much more appropriate (and simpler) to just specify an explicit `padding` for the relevant toolbar containers.
Also, for toolbar buttons placed in `splitToolbarButton`-classes we can reduce some complexity around setting the `margin` (since it should always be zero now).
With these changes, we're thus able to get rid of a couple more `!important`-rules.
- Remove a redundant `margin-top` rule for the `.dropdownToolbarButton`. After the (somewhat) recent UI-refresh all buttons now use `margin: 2px 1px;`, which renders the override unnecessary (and getting rid of an `!important`-rule can't hurt).
- Combine two `.toggled::before` rules, since they're identical.
Note that both the `errorWrapper` HTML and JavaScript code is being ignored in the MOZCENTRAL build, i.e. the *built-in* Firefox PDF Viewer, however the CSS rules are still being included.
That seems totally unnecessary, and while we currently don't have full build-target support in the CSS pre-processor we can actually improve things quite easily anyway. By (ab)using the existing CSS pre-processor, which will remove any non-Firefox CSS rules for the MOZCENTRAL build, it's possible to easily stop bundling any CSS rules by using comments that include a `-webkit`-string.
*Please note:* To easily test that this doesn't break the `errorWrapper` in GENERIC builds, try running e.g. `PDFViewerApplication._otherError("test");` in the web-console.
This special-case was added because the original PresentationMode-implementation used some CSS-tricks to hide everything except the current page. With the changes in PR 14112, which added a PAGE scroll-mode, many of the old PresentationMode-specific hacks could thus be removed from both the JS and CSS code.
This patch is yet another (small) clean-up step, to reduce the number of PresentationMode special-cases used throughout the `BaseViewer`. Note in particular that `BaseViewer.update` now works just fine in PresentationMode[1], and that we only need to ensure that the active page won't *accidentally* change because of the PresentationMode-specific zooming that occurs during page-switching.
---
[1] In the event that we ever want to try and support spread-modes in PresentationMode, which I'm really not keen on doing since documents with varying page sizes will be annoying to handle, these changes would be necessary as well.
The styling of the previous/next-buttons and the findInput, with the elements being "glued" together, was supposed to mimic the styling used in the Firefox *browser* findbar. However, after the most recent re-styling of the Firefox browser UI these elements are now visually separated.
Hence it makes sense, as far as I'm concerned, to try and follow this styling for the findbar used in the GENERIC viewer. One benefit of doing this is that we get more consistent styling, since the buttons now look/behave identically in both the main toolbar and the findbar. Additionally this also simplifies the CSS a bit, since a lot of the existing findbar-specific rules can be removed.
The spread-mode code in `BaseViewer.#ensurePageViewVisible`-method was initially copied from the `BaseViewer._updateSpreadMode`-method, which means that it's slightly more complicated than actually necessary.
In particular, in the PAGE scroll-mode there can only be *one* spread active at a time and we thus don't need to handle insertion of multiple spread-divs.
Given that no HTML element has used the `loadingBox`-id for many years, we obviously don't need to try and hide a non-existent element during printing.
Furthermore, we also shouldn't need to change the `overflow`-value for the `viewerContainer`-element during printing. Originally, many years ago now, we printed "directly" using the viewer and then this apparently made sense.
Given that none of these CSS rules are used at all, unless debugging is enabled, it seems completely unnecessary to load them *unconditionally* for all users.[1]
Note that if *both* the `textLayer` and `pdfBug` debugging hash-parameters are specified simultaneously, we'll now load the `PDFBug`-file *twice* (since the code is simpler that way). However, given first of all that none of this is enabled by default and secondly that using those parameters together isn't helpful[2], potentially loading that file twice is hopefully not an issue.
For the `gulp mozcentral` target, the size of the *built* `viewer.css` file is reduced `> 3%` with this patch.
---
[1] For the Firefox built-in PDF Viewer, in order to even be able to access the `PDFBug` functionality, you need to first of all set `pdfjs.pdfBugEnabled = true` manually in `about:config`. Secondly, you then also need to append the `pdfBug=...` hash-parameter to the URL when *initially* loading the document.
[2] Note how the `textLayer`-settings are already, since essentially forever, overriding the highlighting-features of the "FontInspector"-tab.
This CSS variable is only used together with the `annotationCanvasMap`-functionality in the canvas-code, however its value can be *trivially* computed by using the older `--zoom-factor` CSS variable together with the `PixelsPerInch`-structure.
Rather than having *two different* CSS variables that are this closely linked, it seems better to simplify things by using just one CSS variable instead.
According to the CSS, there should be a visible "divider" after the "Page Width" zoom-option. However, this is being ignored in both Mozilla Firefox[1] and Google Chrome hence the rule is effectively useless now.
Furthermore, the "custom" zoom-option is already being `hidden` using the attribute (in the HTML code) and there should thus be no reason to duplicate this in the CSS as well.
---
[1] Support for *detailed* styling of `<select>`-elements was removed as part of the E10s project.
With just a couple of exceptions, for the `thumbnailView`, all of the sidebarViews share the same basic styling which thus allows for some simplification.
- For the findbar/secondaryToolbar case, the `min-width` rule doesn't really make sense since it's way too small to be useful. Furthermore, the findbar is already specifying its own `min-width` and the secondaryToolbar will (thanks to its buttons) receive a correct/useful width.
- The pageNumber-input already has an *explicit* `width` set, hence setting the `min-width` rule as well is completely unnecessary.
- The treeItem-links are supposed to *compute* their `min-width`, and the static value was only added as a fallback for older browsers without `calc()` support.
In a couple of spots, mostly related to the debugging tools, we're unnecessarily using a somewhat "complex" `background`-format only to specify a solid color. This can be simplified by using `background-color` instead, and the patch also removes a `color`-rule that's being ignored anyway.
After the changes in https://bugzilla.mozilla.org/show_bug.cgi?id=1761839, we no longer need this CSS work-around to prevent the entire `<dialog>` contents from becoming selected when the backdrop is clicked.
When the viewer becomes narrow enough that the sidebar is overlaying the document, which means that the `viewerContainer` is not moving when opening/closing the sidebar, we're currently not removing the `sidebarMoving` CSS class as intended.
While this doesn't cause any *visible* issues, it's nonetheless wrong and should be fixed.
With the changes in PR 8993, a number of the `@media`-related CSS rules became unnecessary. However, it appears that some of these rule were *accidentally* left behind despite being unused now.
Note that previously, when opening the sidebar shifted the position of the main toolbar, we had to take both the sidebar opened *and* closed cases into account in these `@media` rules.
*This is yet another installment in a never-ending series of patches that attempt to simplify and improve old code.*
The `fileInput`-element is used to support the "Open file"-button in the `GENERIC` viewer, however this is very old code.
Rather than creating the element dynamically in JavaScript, we can simply define it conditionally in the HTML code thanks to the pre-processor. Furthermore, the `fileInput`-element currently has a number of unnecessary CSS rules, since the element is *purposely* never made visibly.
Note that with these changes, the `fileInput`-element will now *always* have `display: none;` set. This shouldn't matter, since we can still trigger the `click`-event of the element just fine (via JavaScript) and this patch has been successfully tested in both Mozilla Firefox and Google Chrome.
With the changes in the previous patch, we can simplify the state-tracking by using the `PresentationModeState`-values directly in the `PDFPresentationMode` class.
The `pdfOpenParams` parameter has never really made sense in PresentationMode, since e.g. the zoom-value doesn't (generally) agree with the value chosen by the user prior to entering PresentationMode.
This has never mattered all that much, since the `viewBookmark`-button isn't visible in PresentationMode (nor is any other toolbar button for that matter). However, in the `PDFHistory`-implementation we're currently forced to handle this case specifically since we don't want to populate the browser history with nonsensical state.
Hence it makes overall sense, as far as I'm concerned, to tweak the "updateviewarea" event to include a *simplified* `pdfOpenParams` parameter when PresentationMode is active. Given that the `viewer components` don't include PresentationMode functionality, this change thus shouldn't matter for third-party users.
This method was originally added specifically to work-around bugs/issues related to PresentationMode in Google Chrome. Note that prior to PR 14112 we were using some CSS hacks to only show the current page in PresentationMode, and that could lead to the `getVisibleElements` function not always finding the correct elements.
However, after the changes in PR 14112 we're now using the Page-scrolling mode in PresentationMode and consequently there'll only be *a single* page visible at a time. Hence then `BaseViewer._getCurrentVisiblePage` helper method should no longer be needed, and when testing (locally) in Google Chrome everything seems to work correctly now.
The various functionality in `web/debugger.js` is currently *indirectly* added to the global scope, since that's how `var` works when it's used outside of any functions/closures.
Given how this functionality is being accessed/used, not just in the viewer but also in the API and textLayer, simply converting the entire file to a module isn't trivial[1]. However, we can at least export the `PDFBug`-part properly and then `import` that dynamically in the viewer.
Also, to improve the code a little bit, we're now *explicitly* exporting the necessary functionality globally.
According to MDN, see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import#browser_compatibility, all the browsers that we now support have dynamic `imports` implementations.
---
[1] We could probably pass around references to the necessary functionality, but given how this is being used I'm just not sure it's worth the effort. Also, adding *official* support for these viewer-specific debugging tools in the API feels both unnecessary and unfortunate.
Please note that this patch is purposely quite basic, e.g. it doesn't add the polyfill-CSS in order to simplify the build process, and things such as `::backdrop` thus isn't working.
However, this patch does ensure that older browsers can at least still *access* all of the previous overlays and that things like e.g. opening of password-protected documents respectively printing still works.
This will hopefully improve the a11y a little bit in these dialogs, however there's most definately more things that can be done here (by someone more knowledgeable about a11y).
This way we're able to store the `<dialog>` elements directly, which removes the need to use manually specified name-strings thus simplifying both the `OverlayManager` itself and its calling code.
This replaces our *custom* overlays with standard `<dialog>` DOM elements, see https://developer.mozilla.org/en-US/docs/Web/HTML/Element/dialog, thus simplifying the related CSS, HTML, and JavaScript code.
With these changes, some of the functionality of the `OverlayManager` class is now handled natively (e.g. `Esc` to close the dialog). However, since we still need to be able to prevent dialogs from overlaying one another, it still makes sense to keep this functionality (as far as I'm concerned).
PDFScriptingManager uses the `mousedown` and `mouseup` listeners to keep
track of whether the mouse pointer is pressed in the `isDown` flag.
These listeners were registered to run during the bubbling phase of the
event dispatch, which can be interrupted if any of the previous event
listeners stopped the event propagation. An example of that is by
`GrabToPan` in web/grab_to_pan.js.
Since the mousedown (and mouseup) listeners of PDFScriptingManager are
free of side effects, and the intention is to always run them, it makes
most sense to register them with the capture flag.
After the recent round of patches, I figured that we'd gone as far as possible in replacing `dir`-dependent CSS rules for the viewer.
However, it occurred that me that we could actually use a bit of CSS-trickery to get rid of the remaining ones. More specifically, this was done by defining a CSS variable whose value depends on the document direction and then using that variable together with `calc()` in the affected rules.
*Please note:* I suppose that this could perhaps be seen as a bit too "magical", hence I understand if this patch is ultimately rejected, however this is probably the only simple way to get rid of the remaining `dir`-dependent CSS rules.
The old code would allow an overlay to force close *itself*, before immediately re-opening itself, which actually isn't very helpful in practice since that won't re-run any overlay-specific initialization code.
Given how the overlays are being used this really shouldn't have caused any issues, but it's a bug that we should fix nonetheless.
*Please note:* This is another step in what will, time permitting, become a series of patches to simplify/modernize the viewer CSS.
Rather than having to manually specify ltr/rtl-specific float-values in the CSS, we can use logical `inline-start`/`inline-end` instead (and similar for some related left/right occurrences).
These logical properties depend on, among other things, the direction of the HTML document which we *always* specify in the viewer.
Given that most of these logical CSS properties are fairly new, and that cross-browser support is thus somewhat limited (see below), we rely on PostCSS plugins in order to support this in the GENERIC viewer.
- https://developer.mozilla.org/en-US/docs/Web/CSS/float#browser_compatibility
- https://developer.mozilla.org/en-US/docs/Web/CSS/inset-inline-end#browser_compatibility
Currently we're resolving the Promises in the `_extractTextPromises` Array with the page-index, despite that not really being necessary since the Promises in the Array are explicitly inserted in the correct order.
Furthermore, we can replace the standard `for`-loop with a `for...of`-loop which results in ever so slightly more compact code.
Given that none of these methods were ever intended to be accessed directly from the outside, we can use modern ECMAScript features to ensure that they are indeed private.
This patch also makes `fieldData` private, to remove the old hack used to prevent it from being modified from the outside.
Given that we're now *building* the `web/viewer.css` file used in the development viewer, i.e. with `gulp server`, we no longer need to hard-code these `-webkit`-prefixed rules and can instead let Autoprefixer handle that for us.
To allow using modern CSS features that currently only Mozilla Firefox supports[1], while still enabling development/testing in recent Google Chrome versions, we'll have to start building the `web/viewer.css` file with `gulp server` as well.
In my testing, building the development CSS (and copying the images) takes *less than* `200 ms` on average which is hopefully an acceptable overhead for this sort of feature.
---
[1] In particular `float`, with `inline-start`/`inline-end` values.
This patch fixes an old inconsistency, when using `BasePreferences.{reset, set}`, where the internal Preference values would be kept even if writing them to storage failed.
Given that none of these fields were ever intended to be accessed directly from the *outside*, since that will lead to inconsistent/broken state, we can use modern ECMAScript features to ensure that they are indeed private.
*Please note:* I don't really know anything about a11y, hence it's possible that this patch either doesn't work correctly or at least isn't a complete solution.
In both the SecondaryToolbar and the Sidebar we have "button groups" that functionally acts essentially like radio-buttons. Based on skimming through [this MDN article](https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/Roles/radio_role) it thus appears that we should tag them as such, using `role="radiogroup"` and `role="radio"`, and then utilize the `aria-checked` attribute to indicate to a11y software which button is currently active.
Unfortunately simply using `appearance: textfield;`, or even `-webkit-appearance: textfield;`, doesn't actually hide the "spinner" in number-input elements in e.g. Google Chrome.
Hence we need to use a work-around with the `-webkit-inner-spin-button` rule, however in our CSS code we also have `-webkit-outer-spin-button` currently. According to both [the MDN compatibility data](https://developer.mozilla.org/en-US/docs/Web/CSS/::-webkit-outer-spin-button#browser_compatibility) and also manual testing in Google Chrome Beta 99, the `-webkit-outer-spin-button` rule is no longer necessary and we can thus clean-up the CSS a tiny bit.
This was added in PR 4516 specifically for Safari on iOS devices, but according to MDN it should no longer be necessary now; see https://developer.mozilla.org/en-US/docs/Web/CSS/-webkit-overflow-scrolling#browser_compatibility
According to the MDN compatibility data, this CSS feature:
- Was never implemented anywhere *except* for Safari on iOS.
- Was never standardized and thus never existed in an *unprefixed* version.
- Has now been removed, starting with Safari version 13.
Given that [the FAQ](https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support) already lists Safari as "Mostly" supported, and that the default viewer is written primarily for Mozilla Firefox, it ought to be fine to remove these CSS rules now.
At this point in time, after recent rounds of clean-up, the `webkit`-prefixed Fullscreen API is the only remaining *browser-specific* compatibility hack in the `web/`-folder JavaScript code.
The standard, and thus unprefixed, Fullscreen API has been supported for *over three years* in both Mozilla Firefox and Google Chrome. [According to MDN](https://developer.mozilla.org/en-US/docs/Web/API/Fullscreen_API#browser_compatibility), the unprefixed Fullscreen API has been available since:
- Mozilla Firefox 64, released on 2018-12-11; see https://wiki.mozilla.org/Release_Management/Calendar#Past_branch_dates
- Google Chrome 71, released on 2018-12-04; see https://en.wikipedia.org/wiki/Google_Chrome_version_history
Hence *only* Safari now requires using a prefixed Fullscreen API, and it's thus (significantly) lagging behind other browsers in this regard.
Considering that the default viewer is written *specifically* to be the UI for the Firefox PDF Viewer, and that we ask users to not just use it as-is[1], I think that we should only support the standard Fullscreen API now.
Furthermore, note also that the FAQ already lists Safari as "Mostly" supported; see https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support
---
[1] Note e.g. http://mozilla.github.io/pdf.js/getting_started/#introduction
> The viewer is built on the display layer and is the UI for PDF viewer in Firefox and the other browser extensions within the project. It can be a good starting point for building your own viewer. *However, we do ask if you plan to embed the viewer in your own site, that it not just be an unmodified version. Please re-skin it or build upon it.*
Now that the there's ECMAScript support for properly private methods on `class`es, we can use that instead and thus remove all of the `@private` JSDocs comments.
In some cases, in the `PDFPageView` implementation, we're modifying the `sx`/`sy` properties when CSS-only zooming is being used.
Currently this requires that you remember to *manually* update the `scaled` property to prevent issues, which doesn't feel all that nice and also seems error-prone. By replacing the `scaled` property with a getter, this is now handled automatically instead.
The `CanvasRenderingContext2D.backingStorePixelRatio` property was never standardized, and only Safari set (its prefixed version of) it to anything other than `1`.
Note that e.g. MDN doesn't contain any information about this property, and one of the few sources of information (at this point) is the following post: https://stackoverflow.com/questions/24332639/why-context2d-backingstorepixelratio-deprecated
Hence we can simplify the `getOutputScale` helper function, by removing some dead code, and now it no longer requires any parameters when called.
Given that the `Navigator` interface has been available since "forever", please see https://developer.mozilla.org/en-US/docs/Web/API/Navigator#browser_compatibility, it's somewhat difficult to see why these checks are actually necessary since the viewer is only intended for usage in browsers.
Looking at the history of the code, this functionality was originally placed in the general `src/shared/compatibility.js` file which could thus run in e.g. worker-threads and Node.js environments (where the `Navigator` interface isn't available).
- it aims to fix#14562;
- 'X-\n' were not correctly positioned;
- when X is a diacritic (e.g. in "sä-\n", which is decomposed into "sa¨-\n") we must handle both things:
- diacritics on the one hand;
- "-\n" on the other hand.
This is essentially a *continuation* of PR 7926, where we added support for rejecting the current `PDFDocumentLoadingTask`-promise by throwing inside of the `onPassword`-callback.
Hence the naive way to address [bug 1754421](https://bugzilla.mozilla.org/show_bug.cgi?id=1754421) would be to simply throw in the `onPassword`-callback used in the default viewer. However it unfortunately turns out to not work, since the password input/validation is asynchronous, and we thus need another approach.
The simplest solution that I can come up with here, is thus to *extend* the `onPassword`-callback to also reject the current `PDFDocumentLoadingTask`-instance if an `Error` is explicitly passed as the input to the callback function. (This doesn't feel great, but I cannot see a better solution that isn't really complicated.)
Note that the *browser* findbar in Firefox uses "Title Case" for the labels, and it thus seem like a good idea to ensure that `PDFFindBar` in consistent with that.
Furthermore, the new label added in PR #13261 uses the "Title Case" format which means that currently the default viewer findbar looks inconsistent.
*Please note:* Based on the official Firefox localization docs, see https://firefox-source-docs.mozilla.org/l10n/overview.html#string-updates, changing only the casing should *not* require updating the key:
> 1) If the change is minor, like fixing a spelling error or case, the developer should update the en-US translation without changing the l10n-id.
When the viewer becomes narrow, the `PDFFindBar` will (forcibly) wrap its elements to prevent it from extending to the full window width.
Currently, after PR 13261, this now leads to the `findResultsCount` span taking up vertical space *unconditionally* when the findbar is wrapped. To avoid a blank space being shown in this case, before searching has begun, place the `findResultsCount` span in a "message" rather than an "options" container.
- get original index in using a dichotomic seach instead of a linear one;
- normalize the text in using NFD;
- convert the query string into a RegExp;
- replace whitespaces in the query with \s+;
- handle hyphens at eol use to break a word;
- add some \s* around punctuation signs
With these changes, we'll now *always* replace all whitespaces with standard spaces (0x20). This behaviour is already, since many years, the default in both the viewer and the browser-tests.
This `disableCreateObjectURL` option was originally introduced all the way back in PR 4103 (eight years ago), in order to work-around `URL.createObjectURL()`-bugs specific to Internet Explorer.
In PR 8081 (five years ago) the `disableCreateObjectURL` option was extended to cover Google Chrome on iOS-devices as well, since that configuration apparently also suffered from `URL.createObjectURL()`-bugs.[1]
At this point in time, I thus think that it makes sense to re-evaluate if we should still keep the `disableCreateObjectURL` option.
- For Internet Explorer, support was explicitly removed in PDF.js version `2.7.570` which was released one year ago and all IE-specific compatibility code (and polyfills) have since been removed.
- For Google Chrome on iOS-devices, while we still "support" such configurations, it's *not* the focus of any development and platform-specific bugs are thus often closed as WONTFIX.
Note here that at this point in time, the `disableCreateObjectURL` option is *only* being used in the viewer and any `URL.createObjectURL()`-bugs browser/platform bugs will thus not affect the main PDF.js library. Furthermore, given where the `disableCreateObjectURL` option is being used in the viewer the basic functionality should also remain unaffected by these changes.[2]
Furthermore, it's also possible that the `URL.createObjectURL()`-bugs have been fixed in *browser* itself since PR 8081 was submitted.[3]
Obviously you could argue that this isn't a lot of code, w.r.t. number of lines, and you'd be technically correct. However, it does add additional complexity in a few different viewer components which thus add overhead when reading and working with this code.
Finally, assuming the `URL.createObjectURL()`-bugs are still present in Google Chrome on iOS-devices, I think that we should ask ourselves if it's reasonable for the PDF.js project (and its contributors) to keep attempting to support a configuration if the *browser* developers still haven't fixed these kind of bugs!?
---
[1] According to https://groups.google.com/a/chromium.org/forum/#!topic/chromium-html5/RKQ0ZJIj7c4, which is linked in PR 8081, that bug was mentioned/reported as early as the 2014 (eight years ago).
[2] Viewer functionality such as e.g. downloading and printing may be affected.
[3] I don't have access to any iOS-devices to test with.
So that Firefox doesn't switch to pixel mode for compat with other
browsers.
This should fix https://github.com/mozilla/pdf.js/issues/14476, in terms
of restoring the previous behavior.
We probably want to change the pixel-based scrolling code to not scroll
so much (the deltaMode stuff normalizes to +/-1 tick for each wheel
event, perhaps the pixel-based value should do the same).
- it aims to fix issue #14307;
- this event has been added recently in Firefox and we can now use it;
- fix few bugs in aform.js or in annotation_layer.js;
- add some integration tests to test keystroke events (see `AFSpecial_Keystroke`);
- make dispatchEvent in the quickjs sandbox async.
*Please note:* This is a tentative patch, since I don't know if this is deemed important enough to fix.
The new event could be seen as a *supplement* to the existing "documentinit" and "documentloaded" events, but for the case when a PDF document fails to load.
To make the "documenterror" event generally useful, it'll include both the localized error message as well as the original reason for the error (when that exists).
This helper function has never been used in e.g. the worker-thread, hence its placement in `src/shared/util.js` led to a *small* amount of unnecessary duplication.
After the previous patches this helper function is now *only* used in the viewer, hence it no longer seems necessary to expose it through the official API.
*Please note:* It seems somewhat unlikely that third-party users were relying *directly* on this helper function, which is why it's not being exported as part of the viewer components. (If necessary, we can always change this later on.)
As part of the changes/improvement in PR 14092, we're no longer using the `addLinkAttributes` directly in e.g. the AnnotationLayer-code.
Given that the helper function is now *only* used in the viewer, hence it no longer seems necessary to expose it through the official API.
*Please note:* It seems somewhat unlikely that third-party users were relying *directly* on the helper function, which is why it's not being exported as part of the viewer components. (If necessary, we can always change this later on.)
This structure contains *almost* exclusively references to DOM elements (and a couple of simple strings), rather than complete classes/functions. Hence the `eventBus`-option sticks out a fair bit, and I'd guess that it's *mostly* unused in e.g. third-party implementations.
Given that we, in multiple places, mention that the default viewer shouldn't be used as-is I really don't think that we need to keep this special `eventBus`-option around. Furthermore, nowadays it's also a lot easier to (safely) access the existing `EventBus`-instance in the viewer; see https://github.com/mozilla/pdf.js/wiki/Third-party-viewer-usage#initialization-promise which shows how to listen for the default viewer being initialized (and its `eventBus` thus being available).
Besides converting `Catalog.getPageDict` to an `async` method, thus simplifying the code, this patch also allows us to pro-actively fix a existing issue.
Note how we're looking up References in such a way that `MissingDataException`s won't cause trouble, however it's *technically possible* that the entries (i.e. /Count, /Kids, and /Type) in a /Pages Dictionary could actually be indirect objects as well. In the existing code this could lead to *some*, or even all, pages failing to load/render as intended.
In practice that doesn't *appear* to happen in real-world PDF documents, but given all the weird things that PDF software do I'd prefer to fix this pro-actively (rather than waiting for a bug report).
With `Catalog.getPageDict` being `async` this is now really simple to address, however I didn't want to introduce a bunch more *unconditional* asynchronicity in this method if it could be avoided (since that could slow things down). Hence we'll *synchronously* lookup the *raw* data in a /Pages Dictionary, and only fallback to asynchronous data lookup when a Reference was encountered.
In addition to the above, this patch also makes the following notable changes:
- Let `Catalog.getPageDict` *consistently* reject with the actual error, regardless of what data we're fetching. Previously we'd "swallow" the actual errors except when looking up Dictionary entries, which is inconsistent and thus seem unfortunate. As can be seen from the updated unit-tests this change is API-observable, hence why the patch is tagged `[api-minor]`.
- Improve the consistency of the Dictionary /Type-checks in both the `Catalog.getPageDict` and `Catalog.getAllPageDicts` methods.
In `Catalog.getPageDict` there's a fallback code-path where we're *incorrectly* checking the /Page Dictionary for a /Contents-entry, which is wrong since a /Page Dictionary doesn't need to have a /Contents-entry in order to be valid.
For consistency the `Catalog.getAllPageDicts` method is also updated to handle errors in the /Type-lookup correctly.
- Reduce the `PagesCountLimit.PAUSE_EAGER_PAGE_INIT` viewer constant, to further improve loading/rendering performance of the *second* page during initialization of very long documents; PR 14359 follow-up.
*This addresses the following case missing from the previous patch:*
The viewer is loaded in an *active* window/tab, and enough time is allowed to pass in order to allow rendering to start. However, if the user then switches to another tab (or another program) *before* rendering has finished, the "load" event also needs to be unblocked.
Given that `requestAnimationFrame` is being used, see the `src/diplay/api.js` file, an inactive window/tab means that rendering will not run and we'll thus not fetch all pages. The latter is a requirement for the "load" event to be unblocked, in the MOZCENTRAL-version of, the default viewer.
This patch is a *partial* solution, since it only addresses the following situations:
- A *background* tab (containing the viewer) is reloaded, e.g. via the tab-bar context menu.
- The viewer is loaded in a active tab, but the user switches away from it (or switches to another program window) *before* rendering has started.
This provides a work-around for badly generated PDF documents that contain *negative* /FitH parameters (in the referenced issue the value `-32768` is used).
This patch, first of all, removes circular dependencies in the TypeScript definitions. Secondly, it also moves `RenderingStates` into `web/ui_utils.js` to break another type-dependency and directly use the `XfaLayerBuilder` during XFA-printing.
Finally, note that this patch *slightly* reduces the size of the default viewer (e.g. in the `MOZCENTRAL` build) by not having to bundle code which is completely unused.
This patch circumvents the issues seen when trying to update TypeScript to version `4.5`, by "simply" fixing the broken/missing JSDocs and `typedef`s such that `gulp typestest` now passes.
As always, given that I don't really know anything about TypeScript, I cannot tell if this is a "correct" and/or proper way of doing things; we'll need TypeScript users to help out with testing!
*Please note:* I'm sorry about the size of this patch, but given how intertwined all of this unfortunately is it just didn't seem easy to split this into smaller parts.
However, one good thing about this TypeScript update is that it helped uncover a number of pre-existing bugs in our JSDocs comments.
The size of the `web/ui_utils.js` file has increased over time, as more code has been added to (or moved into) that file. To reduce its size slightly, this patch moves the event-related functionality into a separate file.
In PR 14114 this was only added to the default viewer, which means that in the viewer components the user would need to *manually* implement /Lang handling. This was (obviously) a bad choice, since the viewer components already support e.g. structTrees by default; sorry about overlooking this!
To avoid having to make *two* `getMetadata` API-calls[1] very early during initialization, in the default viewer, the API will now cache its result. This will also come in handy elsewhere in the default viewer, e.g. by reducing parsing when opening the "document properties" dialog.
---
[1] This not only includes a round-trip to the worker-thread, but also having to re-parse the /Metadata-entry when it exists.
By making this API-call *unconditionally*, we introduce a (slight) delay in the initialization of *all* documents.
That seems quite unfortunate, since `pdfjs.enablePermissions` is off by default, and it thus seem better only do the API-call when actually needed; sorry about this!
For encrypted PDF documents without the required permissions set, this patch adds support for disabling of form editing. However, please note that it also requires that the `pdfjs.enablePermissions` preference is set to `true`[1] (since PDF document permissions could be seen as user hostile).
Based on https://www.adobe.com/content/dam/acom/en/devnet/pdf/pdfs/PDF32000_2008.pdf#G6.1942134, this condition hopefully makes sense.
---
[1] Either manually with `about:config`, or using e.g. a [Group Policy](https://github.com/mozilla/policy-templates).
This patch is essentially *another* continuation of PR 11263, which tried to improve loading/initialization performance of *very* large/long documents.
For most documents, unless they're *very* long, we'll eagerly initialize all of the pages in the viewer. For shorter documents having all pages loaded/initialized early provides overall better performance/UX in the viewer, however there's cases where it can instead *hurt* performance.
For documents with a couple of thousand pages[1], the parsing and pre-rendering of the *second* page of the document can be delayed (quite a bit). The reason for this is that we trigger `PDFDocumentProxy.getPage` for *all pages* early during the viewer initialization, which causes the worker-thread to be swamped with handling (potentially) thousands of `getPage`-calls and leaving very little time for other parsing (such as e.g. of operatorLists).
To address this situation, this patch thus proposes temporarily "pausing" the eager `PDFDocumentProxy.getPage`-calls once a threshold has been reached, to give the worker-thread a change to handle other requests.[2]
Obviously this may *slightly* delay the "pagesloaded" event in longer documents, but considering that it's already the result of asynchronous parsing that'll hopefully not be seen as a blocker for these changes.[3]
---
[1] A particularly problematic example is https://github.com/mozilla/pdf.js/files/876321/kjv.pdf (16 MB large), which is a document with 2236 pages and a /Pages-tree that's only *one* level deep.
[2] Please note that I initially considered simply chaining the `PDFDocumentProxy.getPage`-calls, however that'd slowed things down for all documents which didn't seem appropriate.
[3] This patch will *hopefully* also make it possible to re-visit PR 11312, since it seems that changing `Catalog.getPageDict` to an `async` method wasn't the problem in itself. Rather it appears that it leads to slightly different timings, thus exacerbating the already existing issues with the worker-thread being overloaded by `getPage`-calls.
Having recently worked with that method, there's a couple of (very old) issues that I'd also like to address and having `Catalog.getPageDict` be `async` would simplify things a great deal.
These changes improves the consistency ever so slightly in the `PDFOutlineViewer._dispatchEvent` method, by making sure that we can tell the following two cases apart:
- The "pagesloaded" event has *not yet* been fired.
- The "pagesloaded" event has been fired, but no pages were available.
*This patch can be tested e.g. with the `poppler-85140-0.pdf` document from the test-suite.*
For some sufficiently corrupt documents the `getDocument` call will succeed, but fetching even the very first page fails. Currently we only print error messages (in the console) from the `{BaseViewer, PDFThumbnailViewer}.setDocument` methods, but don't actually provide these errors to allow the viewer to handle them properly.
In practice this means that the GENERIC viewer won't display the `errorWrapper`, and in the MOZCENTRAL viewer the *browser* loading indicator is never hidden (since we never unblock the "load" event).
This patch is essentially a continuation of PR 11263, which tried to improve loading/initialization performance of *very* large/long documents.
Note that browsers, in general, don't handle a huge amount of DOM-elements very well, with really poor (e.g. sluggish scrolling) performance once the number gets "large". Furthermore, at least in Firefox, it seems that DOM-elements towards the bottom of a HTML-page can effectively be ignored; for the PDF.js viewer that means that pages at the end of the document can become impossible to access.
Hence, in order to improve things for these *very* large/long documents, this patch will now enforce usage of the (recently added) PAGE-scrolling mode for these documents. As implemented, this will only happen once the number of pages *exceed* 15000 (which is hopefully rare in practice).
While this might feel a bit jarring to users being *forced* to use PAGE-scrolling, it seems all things considered like a better idea to ensure that the entire document actually remains accessible and with (hopefully) more acceptable performance.
Fixes [bug 1588435](https://bugzilla.mozilla.org/show_bug.cgi?id=1588435), to the extent that doing so is possible since the document contains 25560 pages (and is 197 MB large).
This was added on the assumption that the viewer would (eventually) start using the `PDFSinglePageViewer` for e.g. PAGE-scrolling mode and PresentationMode. However, having both a `PDFViewer` and a `PDFSinglePageViewer` side-by-side in the viewer would've been tricky to implement well, which is why PR 14112 implemented PAGE-scrolling for the general `BaseViewer` instead.
Given that the default viewer is no longer (potentially) going to use `PDFSinglePageViewer`, there's code in the `SecondaryToolbar` (and related CSS rules) which is now unnecessary.
*This patch can be tested e.g. with the `sizes.pdf` document in the test-suite.*
While this patch isn't necessarily the best solution, e.g. it might be possible to solve this with *only* CSS, it's what I was able to come up with to address an old issue.
The solution here re-uses the `spread`-class in PresentationMode, since that one already takes care of centering pages *vertically*, together with a dummy-page that takes up the entire height of the window.
Finally, some PresentationMode-related CSS-rules are also simplified slightly, since the changes in PR 14112 (using Page-scrolling) allows some clean-up here.
The issue that this patch fixes has existed ever since the viewer was first re-factored into components, however it only really affects the `disableAutoFetch = true` mode.
By default we're fetching all pages in `BaseViewer.setDocument`, and as part of the parsing/initialization we're also populating the `PDFLinkService`-pagesRefCache. The purpose of that cache is to make navigating to any internal destinations faster, by not having to (asynchronously) lookup the pageNumber via the API when handling the destination.
In comparison, when the `disableAutoFetch = true` mode is being used we're instead *lazily* initializing the pages in the `BaseViewer.#ensurePdfPageLoaded`-method. For some reason, that I can only assume is a simple oversight, we're not attempting to update the `PDFLinkService`-pagesRefCache in that case.
In the `BaseViewer` this cache is mostly relevant in the `disableAutoFetch = true` mode, since the pages are being initialized *lazily* in that case.
In the `PDFThumbnailViewer` this cache is mostly used for thumbnails that are actually being rendered, as opposed to those created directly from the "regular" pages.
Please note that I'm not suggesting that we remove these caches because they're only used in some situations, but rather because they're for all intents and purposes actually *redundant*. In the API itself, we're already caching both the page-promises and the actual pages themselves on the `WorkerTransport`-instance.
Hence these viewer-caches aren't really necessary in practice, and adds what to me mostly seems like an unnecessary level of indirection.[1]
Given that the viewer now relies on caching in the API itself, this patch also adds a new unit-test to ensure that page-caching works (and keep working) as expected.
---
[1] In the `WorkerTransport.getPage`-method the parameter is being validated on every call, but that's hardly enough code to warrant keeping the "duplicate" caches in the viewer in my opinion.
*Please note:* These changes will primarily benefit longer documents, somewhat at the expense of e.g. one-page documents.
The existing `PDFDocumentProxy.getStats` function, which in the default viewer is called for each rendered page, requires a round-trip to the worker-thread in order to obtain the current document stats. In the default viewer, we currently make one such API-call for *every rendered* page.
This patch proposes replacing that method with a *synchronous* `PDFDocumentProxy.stats` getter instead, combined with re-factoring the worker-thread code by adding a `DocStats`-class to track Stream/Font-types and *only send* them to the main-thread *the first time* that a type is encountered.
Note that in practice most PDF documents only use a fairly limited number of Stream/Font-types, which means that in longer documents most of the `PDFDocumentProxy.getStats`-calls will return the same data.[1]
This re-factoring will obviously benefit longer document the most[2], and could actually be seen as a regression for one-page documents, since in practice there'll usually be a couple of "DocStats" messages sent during the parsing of the first page. However, if the user zooms/rotates the document (which causes re-rendering), note that even a one-page document would start to benefit from these changes.
Another benefit of having the data available/cached in the API is that unless the document stats change during parsing, repeated `PDFDocumentProxy.stats`-calls will return *the same identical* object.
This is something that we can easily take advantage of in the default viewer, by now *only* reporting "documentStats" telemetry[3] when the data actually have changed rather than once per rendered page (again beneficial in longer documents).
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[1] Furthermore, the maximium number of `StreamType`/`FontType` are `10` respectively `12`, which means that regardless of the complexity and page count in a PDF document there'll never be more than twenty-two "DocStats" messages sent; see 41ac3f0c07/src/shared/util.js (L206-L232)
[2] One example is the `pdf.pdf` document in the test-suite, where rendering all of its 1310 pages only result in a total of seven "DocStats" messages being sent from the worker-thread.
[3] Reporting telemetry, in Firefox, includes using `JSON.stringify` on the data and then sending an event to the `PdfStreamConverter.jsm`-code.
In that code the event is handled and `JSON.parse` is used to retrieve the data, and in the "documentStats"-case we'll then iterate through the data to avoid double-reporting telemetry; see https://searchfox.org/mozilla-central/rev/8f4c180b87e52f3345ef8a3432d6e54bd1eb18dc/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#515-549
It shouldn't be necessary to iterate through *all* pages when using a non-default `spreadMode`, since we already know which page(s) should become visible.
This code is a left-over from the initial (local) implementation that resulted in PR 14112, however I forgot to clean-up some things such as e.g. this loop.
Also fixes an outdated comment, see PR 14204 which removed the mentioned data-structure.