Refactor C++ QT5 project

We need an existing C++/Qt5 project refactored for the following points: 1. Create comprehensive doxygen documentation 2. Develop an automatic test-suite for this project for full code coverage 3. Fix existing bugs (11 at the time of writing) 4. Add new functionality (6 features) Please find attached the existing source code. This was written in Qt5.9 for Linux. This application shows a grid of live videos from surveillance cameras and displays graphs with additional data next to it. This graph-data is retrieved from a MySQL server. The first two items are of utmost importance: a clear documentation to allow other programmers understand easily. An automatic test suite to ensure advances are on stable footing. The existing bugs are: 1. Sidebar graph height is not saved to user profile. 2. Notes in the future are displayed on the wrong cameras. 3. Application segfault 4. Graph range type is not saved/restored from profile. 5. Logout fails if userlog sql table can't be written 6. Improve user experience when entering and changing user PIN 7. User's custom graph styles are not working 8. Provide popup error messages without repeating 9. Reload datasources and graphs when lastChange column is updated 10. Graph range intervals must be configurable in the database in minutes 11. Video becomes slow in full screen mode Additional features to be added: 1. Display prognostic graph data 2. Display warning/notification icons on videos 3. Define background color gradients for graphs 4. Better avatar gallery for user profiles 5. Custom user themes/colors of the interface 6. Add graph data for direction (wind, current, etc.) This is not a web-project. If you read the entire description, please mention "potato" to know that you have done so. Thanks in advance and waiting for your application. The attached file "Manual de Usuario [login to view URL]" is the user manual in Spanish, which is up-to-date. The attached file "User interface applicacion [login to view URL]" is the initial requirements doc for the creation of this application. It is very outdated, but should give a general idea.