[FEAT] - Custom Theme Support

[bakayu]

Add Custom Theme Support via Configuration Files

Current Behavior:

Themes are currently hardcoded within the application, offering a limited set of predefined options. Check - internal/tui/theme.go

Desired Behavior:

Implement a system that allows users to create and use their own custom themes by placing theme configuration files in a designated directory within their .config folder (e.g., ~/.config/gitx/config.toml). This will enable greater personalization and flexibility.

• Use toml as the config file format. (Open for discussion)
• This would involve adding functionality to check if a file exists at ~/.config/gitx/config.toml. (If it doesn't exist gitx should not bother loading the user provided themes).
• If a file is found, that is ~/.config/gitx/config.toml. It should contain a format as such:

# Default: "GitHub Dark"
theme = "GitHub Dark"

• If a theme is provided in the config.toml file, it would check if it's an inbuilt theme and default to that, if not it would check whether a matching theme is found in themes subdirectory.
• The theme config file should include a format like such:

# General foreground and background colors
Fg = "#ebdbb2"
Bg = "#282828"

# Normal colors
[normal]
Black   = "#282828"
Red     = "#cc241d"
Green   = "#98971a"
Yellow  = "#d79921"
Blue    = "#458588"
Magenta = "#b16286"
Cyan    = "#689d6a"
White   = "#a89984"

# Bright colors
[bright]
Black   = "#928374"
Red     = "#fb4934"
Green   = "#b8bb26"
Yellow  = "#fabd2f"
Blue    = "#83a598"
Magenta = "#d3869b"
Cyan    = "#8ec07c"
White   = "#ebdbb2"

# Dark colors
[dark]
Black   = "#1d2021"
Red     = "#9d0006"
Green   = "#79740e"
Yellow  = "#b57614"
Blue    = "#076678"
Magenta = "#8f3f71"
Cyan    = "#427b58"
White   = "#928374"

• The final config file structure should look like this:

.config/
└ gitx/
    ├ config.toml
    └ themes/
        └ my_custom_theme.toml

Tip

The desired behavior is open to discussion, if you think a better approach or behavior would be better, let us know!

PR Acceptance Criteria:

• gitx must be able to load custom theme files from a ~/.config/gitx/themes directory.
• A clear and well-documented format for theme configuration files must be created and added to the project's documentation.
• Users should be able to switch between both built-in and custom themes from within the application.
• Attach a screenshot or short video showcasing a custom theme being loaded and applied.