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.
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[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.
This patch preserves the old behaviour of appending a `loadingIcon`-div to all pages that are not yet loaded/rendered. However, the actual `loadingIcon`-spinner (i.e. the `loading-icon.gif` image) will only be displayed on *visible* pages to improve performance.
To avoid having to iterate through all pages in the document, which doesn't seem like a good idea for a PDF document with thousands of pages, we use a combination of the currently visible *and* cached pages to toggle the `loadingIcon`-spinner.
This code is the last piece[1] of the viewer that's not using standard `class`es, and by converting this code we get rid of some now unneeded boilerplate code (slightly reducing the size of the *built* `web/viewer.js` file).
Note that while this code was originally imported from a separate repository, it was last sync-ed with upstream *five years* ago which is why this re-factoring should be OK as far as I'm concerned (and we've done some other clean-up since then as well).
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[1] Technically the `web/debugger.js` file is left as well, however that code is first of all not bundled in the *built* `web/viewer.js` file and secondly it's not even loaded by default either.
- First step to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1737260;
- several interactive pdfs use the possibility to hide/show buttons to show different icons;
- render pushbuttons on their own canvas and then insert it the annotation_layer;
- update test/driver.js in order to convert canvases for pushbuttons into images.
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 "pageInfo"-case we'll then proceed to ignore everything except *the first* such event; see https://searchfox.org/mozilla-central/rev/24fac1ad31fb9c6e9c4c767c6a7ff45d226078f3/toolkit/components/pdfjs/content/PdfStreamConverter.jsm#509-514
All-in-all, sending the "pageInfo" telemetry for each rendered page is thus unnecessary and this patch makes the viewer send it only *once* instead.
*This is a tentative patch, since we unfortunately cannot easily test it (as far as I can tell).*
In Firefox this (obviously) works as-is, but in Google Chrome the `markedContent` spans are inserted within the regular text-content (in the DOM) and with non-zero heights.
*This is a tentative patch, since I don't have the necessary hardware to test it.*
See https://developer.mozilla.org/en-US/docs/Web/CSS/text-size-adjust, which is currently ignored in Firefox.
It seems overall safer, and more future-proof, to simply add this to the *entire* `textLayer` rather than its individual elements.
With the previous patch, this helper function is no longer used and keeping it around will simply increase the size of the builds.
This removal is purposely done *separately*, to make it easy to revert the patch in the future if this helper function would become useful again.
This relies on the fact that `Set`s preserve the insertion order[1], which means that we can utilize an iterator to access the *first* stored view.
Note that in the `resize`-method, we can now move the visible pages to the back of the buffer using a single loop (hence we don't need to use the `moveToEndOfArray` helper function any more).
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[1] This applies to `Map`s as well, although that's not entirely relevant here.
The `PDFPageViewBuffer`-code is very important for the correct function of the viewer, but it's currently not tested at all.
While the `PDFPageViewBuffer` is obviously intended to be used with `PDFPageView`-instances, it only accesses a couple of `PDFPageView` properties/methods and consequently it's fairly easy to unit-test this code with dummy-data.
These unit-tests should help improve our confidence in this code, and will also come in handy with other changes that I'm working on (regarding modernizing and re-factoring the `PDFPageViewBuffer`-code).
The way that we're currently handling the last-`id` is very old, and there's no longer any good reason to special-case things when only one thumbnail is visible.
Furthermore, we can also modernize the loop slightly by using `for...of` instead of `Array.prototype.some()` when checking for fully visible thumbnails.
Note how in `PDFPageViewBuffer.resize` we're manually iterating through the visible pages in order to build a Set of the visible page `id`s. By instead moving the building of this Set into the `getVisibleElements` helper function, as part of the existing parsing, this code becomes *ever so slightly* more efficient.
Furthermore, more direct access to the visible page `id`s also come in handy in other parts of the viewer as well.
In the `BaseViewer.isPageVisible` method we no longer need to loop through the visible pages, but can instead directly check if the pageNumber is visible.
In the `PDFRenderingQueue.getHighestPriority` method, when checking for "holes" in the page layout, we can also avoid some unnecessary look-ups this way.
*Sometimes I'll hopefully learn to optimize my code directly when writing it, rather than having to do multiple clean-up passes; sorry about the churn here!*
For most page layouts there won't be any "holes" in the visible pages (or thumbnails), and in those cases it'd obviously be preferable not having to repeat any checks of already rendered pages.
Rather than only checking the "distance" between the first/last pages, we can instead compare the theoretical number of pages (between first/last) with the actually visible number of pages instead. This way, we're able to better detect the "holes"-case and can skip unnecessary parsing in the common case.
I missed this one spot in PR 12870, when converting the other cases in the "keydown" event handler. However, given that it only matters in PresentationMode and/or when "page-fit" zooming is enabled, this oversight shouldn't have had any user-observable impact (but we should fix it nonetheless).
This is a follow-up to PR 10675, since there I completely overlooked that we also need to handle the case where a PDF document has *failed* to load when the "supportsRangedLoading" message is sent to the viewer.
There were some links not working in some XFA files,I realized that the anchor tag that contains the link has an inline display and couldn't receive any height, solved this by adding a "position: absolute". Tested with two different files in Firefox Nightly and Chrome and now all links are working perfectly fine. Added reftest to avoid future regressions
The only reason for using a `DocumentFragment` in the first place, originally added in PR 8724, was to prevent errors in the `PDFPageView`-constructor. However, we should be able to simply make its `container`-option *optional* instead, since it's not being used for anything else in the class.
Note that pre-rendering still works correctly in my testing, and given that the `BaseViewer` keeps references to all `PDFPageView`-instances (via its `_pages` Array) it also shouldn't be possible to "lose" any pages/canvases this way.
Unfortunately there exist PDF documents where all pageLabels are empty strings, see e.g. http://www.cs.cornell.edu/~ragarwal/pubs/blk-switch.pdf (taken from an old issue), which result in the pageNumber-input being completely blank. That doesn't seem very helpful, and this patch simply extends the approach used to ignore pageLabels that are identical to standard page numbering.
In the GENERIC viewer, e.g. when dragging-and-dropping a new PDF document which automatically opens the outline, there can now be breaking errors in the `{BaseViewer, PDFThumbnailViewer}.#getScrollAhead` methods since there's no visible pages/thumbs during loading; sorry about the breakage!
This was a stupid oversight on my part, since the first/last visible pages have obviously already been rendered at the point when we're checking for any potential "holes" in the page layout.
While this will obviously not have any measurable effect on performance, we should nonetheless avoid doing completely unnecessary checks here.
This is a very old "issue", which has existed since essentially forever, and it affects all of the available scrollModes. However, in the recently added Page-mode it's particularily noticeable since we use a *simulated* scroll direction there.
When deciding what page(s) to pre-render, we only consider the current scroll direction. This works well in most cases, but can break down at the start/end of the document by trying to pre-render a page *outside* of the existing ones. To improve this, we'll thus *force* the scroll direction at the start/end of the document.
*Steps to reproduce:*
0. Open the viewer, e.g. https://mozilla.github.io/pdf.js/web/viewer.html
1. Enable vertical scrolling.
2. Press the <kbd>End</kbd> key.
3. Open the devtools and, using the DOM Inspector, notice how page 13 is *not* being pre-rendered.
*Please note:* This is a tentative patch, since I don't have the necessary a11y-software to actually test it.
To avoid having to add a new API-method just for a single string, I figured that adding the new property to the existing `documentInfo`-data (accessed via `PDFDocumentProxy.getMetadata` in the API) will hopefully be deemed acceptable.
Looking at the code, I do have to agree with the point made in issue 12731 about it being unexpected/unhelpful that the `PDFFindController.executeCommand`-method isn't directly usable with the "find"-event.
The reason for it being this way is, as so often, for historical reasons: The `executeCommand`-method was added (just) prior to the introduction of the `EventBus` in the viewer.
Obviously we cannot simply change the existing `PDFFindController.executeCommand`-method, since that'd be a breaking change in code which has existed for over five years.
Initially I figured that we could simply add a new method in `PDFFindController` that'd accept the state from the "find"-event, however after thinking about this and looking through the use-cases in the default viewer I settled on a slightly different approach: Let the `PDFFindController` just listen for the "find"-event (on the `EventBus`-instance) directly instead, which also removes one level of (unneeded) indirection during searching in the default viewer.
For GENERIC builds of the PDF.js library, the old `PDFFindController.executeCommand`-method is still available with a deprecation warning.
Many years ago now there were some `Promise` implementations that had issues resolving with an *implicitly* `undefined` value. That should no longer be the case, and we've not been using the `Promise.resolve(undefined)` format for a long time, hence this patch fixes the few remaining cases.
Having recently worked with this code, in PR 14096 (and indirectly in PR 14112), I happened to notice a pre-existing issue with spreadModes at higher zoom levels.
The `PDFRenderingQueue` code was written back when the viewer only supported "normal" vertical scrolling, and some edge-cases related to spreadModes are thus not perfectly supported. Depending on the zoom level, it's possible that there are "holes" in the currently visible page layout, and those pages will not be pre-rendered as you'd expect.
*Steps to reproduce:*
0. Open the viewer, e.g. https://mozilla.github.io/pdf.js/web/viewer.html
1. Enable vertical scrolling.
2. Enable the ODD spreadMode.
3. Scroll down, such that both pages 1 and 3 are visible.
4. Zoom-in until *only* page 1 and 3 are visible.
5. Open the devtools and, using the DOM Inspector, notice how page 2 is *not* being pre-rendered despite all surrounding pages being rendered.
With the previous commit, both of the `PDFViewer` and `PDFSinglePageViewer` clases are now small/simple enough that it no longer seems necessary to keep them in separate files.
This implements a new Page scrolling mode, essentially bringing (and extending) the functionality from `PDFSinglePageViewer` into the regular `PDFViewer`-class. Compared to `PDFSinglePageViewer`, which as its name suggests will only display one page at a time, in the `PDFViewer`-implementation this new Page scrolling mode also support spreadModes properly (somewhat similar to e.g. Adobe Reader).
Given the size and scope of these changes, I've tried to focus on implementing the basic functionality. Hence there's room for further clean-up and/or improvements, including e.g. simplifying the CSS/JS related to PresentationMode and implementing easier page-switching with the mouse-wheel/arrow-keys.
Note that PR 14049 removed this, since https://github.com/mozilla/pdf.js/pull/14049#discussion_r716245518 claimed that it's not necessary anymore. Unfortunately that, in my testing on Windows, actually re-introduced exactly the issue described in the comment; more specifically once the *last* character has been entered in the comb-field it's now again incorrectly scrolled (with the first character being invisible) until focus is lost.
This can be tested with e.g. `f1040.pdf`, see page 2, from the test-suite.
This patch helps reduce some duplication, given that we now have a few essentially identical `addLinkAttributes` call-sites in the code-base.
To prevent runtime errors in the Annotation/XFA-layer code, we'll warn if a custom/incomplete `PDFLinkService` is being used (limited to GENERIC builds).
Please note that we (obviously) don't want to unconditionally pre-render more than one page all the time, since that could very easily lead to overall worse performance in some documents.[1]
However, when spreadModes are enabled it does make sense to attempt to pre-render both of the pages of the next/previous spread.
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[1] Since it may cause pre-rendering to unnecessarily compete for parsing resources, on the worker-thread, with "regular" rendering.
Note how both the annotationLayer and the document outline will apply various URL-related options when creating the link-elements.
For consistency the `xfaLayer`-rendering should obviously use the same options, to ensure that the existing options are indeed applied to all URLs regardless of where they originate.
- it aims to fix https://bugzilla.mozilla.org/show_bug.cgi?id=1716758;
- some buttons have a JS action with the pattern `app.launchURL(...)` (or similar) so extract when it's possible the url and generate a <a> element with the href equals to the found url;
- pdf.js already had some code to handle that so this patch slightly refactor that.
This replaces direct `document.getElementsByName` lookups with a helper method which:
- Lets the AnnotationLayer use the data returned by the `PDFDocumentProxy.getFieldObjects` API-method, such that we can directly lookup only the necessary DOM elements.
- Fallback to using `document.getElementsByName` as before, such that e.g. the standalone viewer components still work.
Finally, to fix the problems reported in issue 14003, regardless of the code-path we now also enforce that the DOM elements found were actually created by the AnnotationLayer code.
With these changes we'll thus be able to update form elements on all visible pages just as before, but we'll additionally update the AnnotationStorage for not-yet-rendered elements thus fixing a pre-existing bug.
Currently any AppOptions set using e.g. the "webviewerloaded" event listener can/will by default be overridden when the Preferences are read.
To avoid that happening the "disablePreferences"-option can be used, however unless it's been explicitly set all non-default AppOptions will be silently ignored. This patch thus attempts to improve the current situation somewhat, for third-party implementations, by logging a warning in the console when this happens.
Rather than re-computing this value in a number of different places throughout the code-base[1], we can expose this in the API via the existing `PixelsPerInch`-structure instead.
There's also been feature requests asking for the old `CSS_UNITS` viewer constant to be made accessible, such that it could be used in third-party implementations.
I suppose that it could be argued that it's somewhat confusing to place a unitless property in `PixelsPerInch`, however given that the `PDF_TO_CSS_UNITS`-property is defined strictly in terms of the existing properties this is hopefully deemed reasonable.
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[1] These include:
- The viewer, with the `CSS_UNITS` name.
- The reference-tests.
- The display-layer, when rendering images; see PR 13991.
Given the simplicity of this functionality, we can move it from the default viewer and into the `BaseViewer` class instead. This way, it's possible to support more scripting functionality in the standalone viewer components; please see PR 14038.
Please note that I purposely went with `increaseScale`/`decreaseScale`-method names, rather than using "zoom", to better match the existing `currentScale`/`currentScaleValue` getters/setters that's being used in the `BaseViewer` class.
Rather than forcing the "regular" `EventBus` to check and handle `isInAutomation` for every `dispatch` call, we can take advantage of subclassing instead.
Hence this PR introduces a new `AutomationEventBus` class, which extends `EventBus`, and is used by the default viewer when `isInAutomation === true`.
Originally the library/viewer didn't support forms, and the hiding of the Download-buttons (when new documents are opened) didn't really matter all that much. Hence the simplest solution, at the time, was to hide the Download-buttons since we use the URL as a fallback when downloading data in the GENERIC `DownloadManager`.
Nowadays we obviously want to support saving of forms in the GENERIC viewer, regardless of how the document was opened, which could thus *potentially* lead to the fallback download-URL being wrong.
In order to be able to show the Download-buttons unconditionally, this patch slightly re-factors the viewer to track the download-URL *separately* to prevent any issues there.
*Please note:* As mentioned in the issue, the ViewBookmark-buttons are specific to the initial URL when the viewer is first opened. Hence they (still) don't make sense when a new document has been opened, since it's then impossible to obtain a usable link to the *currently* active document.
By using CSS variables to set the width of the zoom dropdown, we can simplify both the relevant CSS and JS code. This will not only improve overall maintainability of this code, but should also make it (slightly) easier for third-party users that want to customize the width.
Note in particular that by having the code in `Toolbar._adjustScaleWidth` lookup the values of the CSS variables, we no longer need to worry about keeping hard-coded values up-to-date with the CSS rules.
While some of the output looks worse to my eye, this behavior more
closely matches what I see when I open the PDFs in Adobe acrobat.
Fixes: #4706, #9713, #8245, #1344
