dotfiles/nvim/lua/colors.lua

-- Eryn Wells <eryn@erynwells.me>

-- Allow using GUI style colors (#RRGGBB hex codes) in color terminals if we
-- know it can do it. This is required for most modern color themes. Apple's
-- Terminal.app doesn't have True Color support though, so make sure it's
-- off for that.
--vim.g.termguicolors = not vim.env.TERM_PROGRAM == "Apple_Terminal"

local function _highlight_trailing_whitespace()
    local should_create_highlight_match = true

    local group = vim.api.nvim_create_augroup("ListModeTrailingWhitespace", { clear = true })

    local callback = function(env)
        local list_mode_enabled = vim.api.nvim_get_option_value("list", { })
        if list_mode_enabled then
            vim.cmd [[ highlight link TrailingWhitespace ErrorMsg ]]
            if should_create_highlight_match then
                vim.cmd [[ match TrailingWhitespace /\v\s+$/ ]]
                should_create_highlight_match = false
            end
        else
            vim.cmd [[ highlight clear TrailingWhitespace ]]
        end
    end

    vim.api.nvim_create_autocmd("OptionSet", {
        pattern = "list",
        group = group,
        callback = callback,
    })

    vim.api.nvim_create_autocmd("BufWinEnter", {
        group = group,
        callback = callback,
    })
end

local function _create_autocmds()
    local colorscheme_group = vim.api.nvim_create_augroup("ColorSchemeOverrides", { clear = true })

    vim.api.nvim_create_autocmd("ColorScheme", {
        callback = function()
            vim.cmd [[
                hi! ColorColumn cterm=NONE ctermbg=233
                hi! CursorColumn cterm=NONE ctermbg=233
                hi! CursorLine cterm=NONE ctermbg=233
                hi! CursorLineNr cterm=bold ctermfg=White ctermbg=233
                hi! LineNr ctermfg=DarkGray ctermbg=233
            ]]
        end,
        group = colorscheme_group,
    })

    vim.api.nvim_create_autocmd("ColorScheme", {
        pattern = "default",
        callback = function()
            vim.cmd [[ hi! NormalFloat ctermfg=8 ]]
        end,
        group = colorscheme_group,
    })

    vim.api.nvim_create_autocmd("ColorScheme", {
        pattern = "dracula",
        callback = function()
            vim.cmd [[ highlight CursorLineNr guibg=#44475a ]]
        end,
        group = colorscheme_group,
    })

    vim.api.nvim_create_autocmd("ColorScheme", {
        pattern = "witchhazel",
        callback = function()
            vim.cmd [[
                hi! default link LineNr CursorLineNr
                hi! default link CursorLineNr CursorLine
            ]]
        end,
        group = colorscheme_group,
    })

    vim.api.nvim_create_autocmd("ColorScheme", {
        pattern = "zaibatsu",
        callback = function()
            vim.cmd [[
                hi! Pmenu ctermbg=8
                hi! VertSplit ctermbg=8
            ]]
        end,
        group = colorscheme_group,
    })
end

local function init_colors()
    _highlight_trailing_whitespace()
    _create_autocmds()

    vim.cmd [[ color zaibatsu ]]
end

return {
    init = init_colors
}