This replaces our custom `PromiseCapability`-class with the new native `Promise.withResolvers()` functionality, which does *almost* the same thing[1]; please see https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers
The only difference is that `PromiseCapability` also had a `settled`-getter, which was however not widely used and the call-sites can either be removed or re-factored to avoid it. In particular:
- In `src/display/api.js` we can tweak the `PDFObjects`-class to use a "special" initial data-value and just compare against that, in order to replace the `settled`-state.
- In `web/app.js` we change the only case to manually track the `settled`-state, which should hopefully be OK given how this is being used.
- In `web/pdf_outline_viewer.js` we can remove the `settled`-checks, since the code should work just fine without it. The only thing that could potentially happen is that we try to `resolve` a Promise multiple times, which is however *not* a problem since the value of a Promise cannot be changed once fulfilled or rejected.
- In `web/pdf_viewer.js` we can remove the `settled`-checks, since the code should work fine without them:
- For the `_onePageRenderedCapability` case the `settled`-check is used in a `EventBus`-listener which is *removed* on its first (valid) invocation.
- For the `_pagesCapability` case the `settled`-check is used in a print-related helper that works just fine with "only" the other checks.
- In `test/unit/api_spec.js` we can change the few relevant cases to manually track the `settled`-state, since this is both simple and *test-only* code.
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[1] In browsers/environments that lack native support, note [the compatibility data](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Promise/withResolvers#browser_compatibility), it'll be polyfilled via the `core-js` library (but only in `legacy` builds).
This old method is essentially just adding, a small amount of, unnecessary indirection and we can easily invoke `PDFViewerApplication.open` directly from the extension-specific code instead.
The following are some highlights of this patch:
- In the Worker we only extract a *subset* of the potential contents of the `Usage` dictionary, to avoid having to implement/test a bunch of code that'd be completely unused in the viewer.
- In order to still allow the user to *manually* override the default visible layers in the viewer, the viewable/printable state is purposely *not* enforced during initialization in the `OptionalContentConfig` constructor.
- Printing will now always use the *default* visible layers, rather than using the same state as the viewer (as was the case previously).
This ensures that the printing-output will correctly take the `Usage` dictionary into account, and in practice toggling of visible layers rarely seem to be necessary except in the viewer itself (if at all).[1]
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[1] In the unlikely case that it'd ever be deemed necessary to support fine-grained control of optional content visibility during printing, some new (additional) UI would likely be needed to support that case.
The function caretPositionFromPoint return the position within the last visible element
and sometimes there are some elements on top of the ones in the text layer.
So the idea is to hide the visible elements which aren't in the text layer in order
to get the right caret position.
Currently the `web/app.js` file pulls in various build-specific dependencies, via the use of import maps, and those files in turn import from `web/app.js` thus creating undesirable import cycles.
To avoid this we instead pass in a `PDFViewerApplication`-reference, immediately after it's been created, to the relevant code.
Note that we use an ESLint plugin rule, see `import/no-cycle`, that is normally able to catch import cycles. However, in this case import maps are involved which is why this wasn't caught.
Having this parameter among a list of DOM-elements seems slightly strange now, however this is very old code hence the explanation for why this was done is for historical reasons (as is often the case).
Hence we can simply move this into `AppOptions` instead, which seems more appropriate overall.
Given that only the GENERIC viewer supports opening more than one PDF document, we can simplify things a tiny bit by instead generating the necessary DOM-element in JavaScript.
The `DefaultExternalServices` code, which is used to provide build-specific functionality, is very old. This results in a pattern where we first initialize `PDFViewerApplication.externalServices` and then *override* it for the different builds.
By converting `DefaultExternalServices` into a "regular" class, and leveraging import maps, we can directly initialize the correct instance depending on the build.
Given the simplicity of the `createPreferences` method, we can leverage import maps to directly initialize the correct `Preferences`-instance depending on the build.
Given the simplicity of the `createDownloadManager` method, we can leverage import maps to directly initialize the correct `DownloadManager`-instance depending on the build.
For arrow functions that are both simple and short, we can avoid using explicit `return` to shorten them even further without hurting readability.
For the `gulp mozcentral` build-target this reduces the overall size of the output by just under 1 kilo-byte (which isn't a lot but still can't hurt).
The system locale (used in OffscreenCanvas) can be different from the one guessed by Fluent,
consequently, in order to avoid any mismatch, we just use an attached canvas element.
The original issue can easily be reproduced locally in adding a lang="ja" in viewer.html
(or with an other language for Japanese users).
The doorhanger for highlighting has a basic color picker composed of 5 predefined colors
to set the default color to use.
These colors can be changed thanks to a preference for now but it's something which could
be changed in the Firefox settings in the future.
Each highlight has in its own toolbar a color picker to just change its color.
The different color pickers are so similar (modulo few differences in their styles) that
this patch introduces a new class ColorPicker which provides a color picker component
which could be reused in future editors.
All in all, a large part of this patch is dedicated to color picker itself and its style
and the rest is almost a matter of wiring the component.
Given that this event listener is only used to trigger rendering after the sidebar has been opened/closed, we can utilize the existing one in the `PDFSidebar` class for this purpose instead. That one is registered on the sidebar DOM-element, and is needed to remove a CSS-class indicating that the sidebar is moving.
The `viewerCssTheme`-implementation has always been somewhat hacky, and now it's also *partially* broken ever since we've started using CSS nesting.
Trying to support nested media queries would thus require a lot more parsing of the CSS rules, which seems inefficient and thus generally undesirable.[1]
As discussed on Matrix, let's try to remove the `viewerCssTheme`-option and see if there's any (significant) fallout from this.
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[1] If this option is brought back, it seems to me that it (in Firefox) should probably be set through the platform-code that handles theming.
With the changes in PR 17208, where browser-preferences are now handled as "regular" viewer-options, we can tweak the definition of `canvasMaxAreaInBytes` to slightly simplify things in the `PDFViewerApplication.open` method.
Currently we *synchronously* fetch a number of browser preferences/options, from the platform code, during the viewer respectively PDF document initialization paths.
This seems unnecessary, and we can re-factor the code to instead include the relevant data when fetching the regular viewer preferences.
This patch changes almost all viewer-components[1] to use "data-l10n-id"/"data-l10n-args" for localization, which means that in many cases we no longer need to pass around the `L10n`-instance any more.
One part of the code-base where the `L10n`-instance is still being used "directly" is the AnnotationEditors, however while it might be possible to convert (most of) that code as well that's not attempted in this patch.
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[1] The one exception is the `PDFDocumentProperties` dialog, since the way it's currently implemented makes that less straightforward to fix without a lot of code changes.
Given that there's now a bit more asynchronicity in the l10n-initialization in the Firefox PDF Viewer, after PR 17115, try to limit the impact of that by moving it to occur a tiny bit earlier in the default viewer initialization.
In Firefox debug builds, there is an assertion to check that we don't connect
a subelement of an already connected root. Thanks to this assertion, we can see
that the root has already been added to Fluent, hence we don't need to do it
a second time.
We don't need to await anymore on the translation in order to update the
toolbar: it'll be done by Fluent, so we can safely remove the "localized"
event and avoid to wait for it.
