TODO
    General:
        ✓ Internationalization
        ✓ Application icon
        ✓ .desktop file    
        Flatpak and AppImage support    
    Options:
        ✓ Automatic library management
            ✓ Recursive file addition
            ✓ Auto deletion
        ✓ Remember files
        ✓ Check files (hashes) upon restart
        ✓ Draw shadows
        ✓ Perform culling
    Library:
        ✓ sqlite3 for cover images cache
        ✓ sqlite3 for storing metadata
        ✓ Drop down for SortBy
        ✓ Image delegates
        ✓ Image reflow
        ✓ Search bar in toolbar
        ✓ Shift focus to the tab that has the book open
        ✓ Tie file deletion and tab closing to model updates
        ✓ Create separate thread for parser - Show progress in main window
        ✓ Memory management
        ✓ Mass tagging
        ✓ Add capability to sort by new
        ✓ Table view
        ✓ Context menu: Cache, Read, Edit database, delete, Mark read/unread
        ✓ Information dialog widget
        ✓ Allow editing of database data through the UI + for Bookmarks
        ✓ Include (action) icons with the applications
        ✓ Drag and drop support for the library
        ✓ Tab reordering
        Set focus to newly added file
    Reading:
        ✓ Drop down for TOC
        ✓ Override the keypress event of the textedit
        ✓ Use format* icons for toolbar buttons
        ✓ Implement book view settings with a(nother) toolbar
        ✓ Substitute textedit for another widget
        ✓ Theming
        ✓ Keep fontsize and margins consistent - Let page increase in length
        ✓ Fullscreening
        ✓ Remember open tabs
        ✓ Selectable background color for QGraphicsView
        ✓ View modes for QGraphicsView
        ✓ View and hide toolbar actions in a list
        ✓ Line spacing
        ✓ Record progress
        ✓ Text alignment
        ✓ Background color
        ✓ Bookmarks
            ✓ Creation
            ✓ Navigation
            ✓ Editing: Name
            ✓ Deletion
        ✓ Cache next and previous images
        ✓ Set context menu for definitions and the like
        ✓ Paragraph indentation
        ✓ Comic view keyboard shortcuts
        ✓ Comic view context menu
        ✓ Make the bookmark dock float over the reading area
        ✓ Spacebar should not cut off lines at the top
        ✓ Track open bookmark windows so they can be closed quickly at exit
        ✓ Search document using QTextCursor
        Double page / column view
            ✓ For comics
                Caching is currently non functional
        Annotations
            ✓ Text
            ✓ Disable buttons for annotations, search in images
        Adjust key navigation according to viewport dimensions
    Filetypes:
        ✓ pdf support
            Parse TOC
        ✓ epub support
            ✓ Homegrown solution please
        ✓ cbz, cbr support
            ✓ Keep font settings enabled but only for background color
            ✓ Double page view
            ✓ Manga mode
        ✓ mobi, azw support
            Limit the extra files produced by KindleUnpack
                Have them save to memory
        ✓ fb2 support
            ✓ Images need to show up in their placeholders
        djvu support
    Other:
        ✓ Define every widget in code
    Bugs:
        Deselecting all directories in the settings dialog also filters out manually added books
        Clean up 'switch' page layout
        Colors aren't loaded properly for annotation previews
        Last line in QTextBrowser should never be cut off
        Does image alignment need to be centered?

    Secondary:
        Graphical themes
        Change focus rectangle dimensions
        Universal Ctrl + Tab
        Allow tabs to detach and form their own windows
        Goodreads API: Ratings, Read, Recommendations
        Get ISBN using python-isbnlib
        Use embedded fonts + CSS
        Shift to logging instead of print statements
        txt, doc, chm support
        Include icons for filetype emblems
        Comic view modes
            Continuous paging
        Ignore a / the / numbers for sorting purposes
        ? Add only one file type if multiple are present
        ? Create emblem per filetype
        In application notifications
        Notification in case the filter is filtering out all files with no option in place
        Option to fit images to viewport

    Need help with:
        Double page view for books
        Scrolling: Smooth / By Line
        Annotation preview in listView
        Pagination