Splash screen

[georgy7]

The purpose of this screen is to help users complete installation.
Background art is completely unnecessary and even undesirable, as well as any delay before launching the main window when all checks have been passed.

It can be implemented as a separate window or be embedded in the main window using a technique similar to those used in the setup assistants (see screens.tcl).

screens.zip

What should it do:

1. It checks whether the CLI application is installed and is it supported version.
   • It shows the result of the check (OK/Failed).
   • If the check fails, it displays additional information about where catframes is and what its version is, what version is expected.
2. It checks whether installed FFmpeg and supported fonts.
   • It shows the result of the checks (OK/Failed).
   • If the checks fails, it displays how to install it on this system. You need to determine the type of Linux distribution (deb, rpm), and if possible, immediately provide the correct command for installation. On Windows, the splash screen displays FFmpeg builds hyperlink and a button or hyperlink to installation instructions. And I'm not sure how to install FFmpeg on a Mac, maybe you know a simple way.
3. It checks the Python version. Whether it fits. It makes sense since missing features don't always cause crash at startup.
   • It shows the result of the checks (OK/Failed).
   • If the check fails, it displays what version is it, what minimum version is required.
4. Optional: It does not crash when there is no Pillow on the system.
   • It shows the result of this check (OK/Failed).
   • If the check fails, it displays short message about it. This message must conain Pillow on PyPI link.

If all checks are passed, the splash screen immediately switches to the main window. Otherwise, it remains open and the main window does not appear (button for manual switching to the main window is also not needed).

i18n

All labels on the splash screen must be localized.
Supported languages so far:

• English
• Russian

Expected view

Something like this (with clickable hyperlinks, etc.):

catframes.py .................................................. OK
FFmpeg ........................................................ Failed

    blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah (additional info)

Python ........................................................ Failed

    blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah (additional info)

Pillow ........................................................ Failed

    blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah blah blah
    blah blah blah blah blah blah blah blah blah blah blah (additional info)