I'm new to plugin development, so I would appreciate any help, tips or advice.
I am creating a theme -- let's call it x-theme -- that comes in six different colours. The files for each colour variant are the same; the only one that differs is the CSS file, so there are 6 CSS files.
However, I don't want the user to have to upload six different themes (i.e. effectively uploading all the theme files 6 times).
So, I want a plugin that allows the wp-admin user (not the site user) to switch the CSS file for x-theme. I want the plugin to create a page in the admin panel, perhaps under "Design", that says "X-Theme-Switcher".
On that page, the user should be able to choose his colour options
and click a save button.
Depending on which colour option is selected, the corresponding stylesheet from within the theme folder should be loaded within
Finally, I want this plugin to be part of the functions.php file in the theme, so when the user installs the theme, they automatically install the plugin.
So, my question is: how difficult will this be? Is there anything (e.g. similar plugin) that I can use to give me a headstart? Tips or advice greatly appreciated.