Html / Epub reader implementation

[michalrentka]

No description provided.

[jarbus]

I've literally been stalking this repo since last November because I've been so excited for epub support in Zotero haha, so great to see this PR

[mvasilak]

Some first comments. More will follow.

[chenggiant]

Looking forward to the epub and html support!

[haidar47x]

Glad to see it being implemented. :)

[mvasilak]

@michalrentka some comments from testing ePUB attachments.

General

• When I download an attachment to open, rarely, it opens empty and I have to close the reader and open it again, for the document to appear. Could there be a potential race issue when downloading, copying to temporary folder, and loading the document?
• For images in the document, e.g. a cover, I can hold-tap to get a context menu, which is nice, unless we think it may cause some confusion.

• I can even select text on an image, which may be confusing if a user tries to annotate it (like I tried 😅).

Annotations

• Creating an annotation may create 2 annotations with some text overlapping.

• Creating further annotations, may not be rendered, although text is selected, and you get an error like:

[ERROR] Zotero(+0000001): HtmlEpubDocumentViewController: navigating to 6NREE26N failed - Error Domain=WKErrorDomain Code=4 "A JavaScript exception occurred" UserInfo={WKJavaScriptExceptionLineNumber=31037, WKJavaScriptExceptionMessage=Error: Unsupported FragmentSelector.conformsTo: undefined, WKJavaScriptExceptionColumnNumber=103, WKJavaScriptExceptionSourceURL=file:///.../view.js, NSLocalizedDescription=A JavaScript exception occurred}. [(155) HtmlEpubDocumentViewController.selectInDocument(key:); com.apple.main-thread]

• Closing and re-opening the document after, in both iOS & macOS, will show a blank screen, as it seems corrupted. (No errors are logged in iOS log when re-opening)
• Trying to delete an annotation from the sidebar in this state, logs this error (although the annotation is deleted):

[ERROR] Zotero(+0000000): HtmlEpubDocumentViewController: updating document failed - Error Domain=WKErrorDomain Code=4 "A JavaScript exception occurred" UserInfo={WKJavaScriptExceptionLineNumber=31037, WKJavaScriptExceptionMessage=Error: Unsupported FragmentSelector.conformsTo: undefined, WKJavaScriptExceptionColumnNumber=103, WKJavaScriptExceptionSourceURL=file:///.../view.js, NSLocalizedDescription=A JavaScript exception occurred}. [(167) HtmlEpubDocumentViewController.updateView(modifications:insertions:deletions:); com.apple.main-thread]

• Deleting all the annotations (only possible in iOS), eliminates the corrupted state, and re-opening the document displays it as expected.

Rendering

• It’s not always the same in macOS and iOS, which makes sense, but I may see empty pages in iOS, that I don’t see in macOS.
• Decreasing reader height, e.g. by moving the toolbar to the top, may hide some of the bottom content.
• Changing reader size in any way, e.g. by rotating, will render annotation rects in the wrong place.

Navigation

• It would be nice to have a table of contents in the sidebar.
• It would be nice to have page controls in the toolbar.
• Tapping a link would be nice to create a back button.

[mvasilak]

@michalrentka some comments from testing snapshot attachments.

General

• Taping an external link doesn't open it in a the browser or an in-app safari view controller. In macOS it is opened in browser.
• Snapshots with existing annotations, perhaps created in previous versions of the macOS client, seem to have breaking changes, resulting in annotations not showing in iOS and logging errors even for selecting an annotation tool. I'm not sure if this will be an issue when we release the feature for iOS.

Annotations

Creating annotations from text selection is not very accurate, and could result in:

• Missing characters from start or end.
• Adding more characters than selected.
• Drawing an annotation that e.g. underlines more than the annotation's text, usually a whole paragraph.
• Creating more than one annotations at the same time.

These issues seem to stem from the inconsistency of the text selection box and the annotation being drawn, as if two separate text selections are considered in the end. Could be related to web view configuration.

Check the following example:

snapshots-in-ios.mov

[michalrentka]

• For images in the document, e.g. a cover, I can hold-tap to get a context menu, which is nice, unless we think it may cause some confusion.

* I can even select text on an image, which may be confusing if a user tries to annotate it (like I tried 😅).

@dstillman what do you think about this? In my opinion this is actually fine as it's a feature that iOS provides. Yes it might be confusing when you try to select text and annotate it and you don't notice that you're actually selecting text in an image (so you don't have any option to annotate), but I guess that's on you. It should be possible to disable this functionality if you think it's counterproductive though.

[michalrentka]

@mvasilak you can try to re-test. Hopefully all or at least most issues should be fixed now. Some were caused by me incorrectly passing the data to reader, others were in the reader itself. I left image handling as is for now.

[mvasilak]

@michalrentka things look improved. Some new observations:

both ePUBS & snapshots

• onSetSelectionPopup is ignored if an annotation tool is selected, is this intended? This breaks muscle memory learned from PDF reader.
• Page number label in annotation sidebar cells/popovers, as well as page edit actions, should be omitted, same as in desktop.
• Annotation tools remains open after toolbar has been closed.

snapshots only

• Selecting an annotation with sidebar open doesn’t scroll to its cell.
• Annotations that cover more than the visible screen, e.g. created in desktop by selecting text and scrolling, may not always show a popover, but still may cause a dismissal event, which w/o presented popover will dismiis the reader.