Script to toggle dark mode on and off on MacOS

darkmode

#!/bin/bash
# usage: darkmode [dark|light]

set -euo pipefail
shopt -s nocasematch

if [[ $# > 0 ]]; then
    # mode given
    case "$1" in
        dark)
            DARK_MODE=true
            ;;
        light)
            DARK_MODE=false
            ;;
        *)
            echo "ERROR expected either 'dark' or 'light'"
            exit 1
            ;;
    esac
    shift

else
    # Get the current macOS appearance setting
    current_theme=$(defaults read -g AppleInterfaceStyle 2>/dev/null || true)
    case "$current_theme" in
        Dark)
            DARK_MODE=false
            ;;
        *)
            DARK_MODE=true
            ;;
    esac
fi

osascript -e 'tell application "System Events" to tell appearance preferences to set dark mode to '$DARK_MODE
if [[ "$DARK_MODE" == false ]]; then
    echo "Switched to Light mode"
else
    echo "Switched to Dark mode"
fi

vimrc

function! SetThemeBasedOnSystem()
  " Check if running on macOS (Darwin)
  if has("macunix")
    let sys_theme = system("defaults read -g AppleInterfaceStyle 2>/dev/null")

    " Check the output and set the background accordingly
    if sys_theme =~ "Dark"
      set background=dark
    else
      set background=light
    endif
  endif
endfunction
call SetThemeBasedOnSystem()

" Optionally, use an autocommand to refresh the background when Vim regains focus
augroup ThemeAutoSwitch
    autocmd!
    autocmd FocusGained * call SetThemeBasedOnSystem()
augroup END