nvim/lua/config/autocmds.lua

local function augroup(name)
    return vim.api.nvim_create_augroup("my_" .. name, { clear = false })
end

vim.api.nvim_create_autocmd(
    { "BufEnter", "FocusGained", "InsertLeave", "WinEnter", "CmdlineLeave" },
    {
        group = augroup("toggle_relative_number"),
        callback = function()
            if not vim.opt.number:get() and not vim.opt.relativenumber:get() then
                return
            end
            vim.opt.relativenumber = vim.api.nvim_get_mode().mode ~= "i"
        end,
    }
)

vim.api.nvim_create_autocmd(
    { "BufLeave", "FocusLost", "InsertEnter", "WinLeave", "CmdlineEnter" },
    {
        group = augroup("toggle_relative_number"),
        callback = function(ev)
            vim.opt.relativenumber = false
            if ev.event == "CmdlineEnter" then
                vim.cmd("redraw")
            end
        end,
    }
)

-- close some filetypes with <q>
vim.api.nvim_create_autocmd({ 'FileType' }, {
	pattern = { 'qf', 'help', 'man', 'lspinfo', 'spectre_panel', 'lir' },
	callback = function(event)
		vim.bo[event.buf].buflisted = false
		vim.keymap.set("n", "q", "<cmd>close<cr>", { buffer = event.buf, silent = true })
	end,
})

vim.api.nvim_create_autocmd({ 'FileType' }, {
	pattern = { 'cpp', 'cc', 'hpp', 'hh', 'md', 'markdown', 'java' },
	callback = function()
		vim.opt.ts = 4
		vim.opt.sw = 4
		vim.opt.expandtab = true
	end,
})

-- Highlight on yank
vim.api.nvim_create_autocmd({ 'TextYankPost' }, {
	callback = function()
		vim.highlight.on_yank { higroup = 'Visual', timeout = 200 }
	end,
})

-- resize splits if window got resized
vim.api.nvim_create_autocmd({ "VimResized" }, {
	callback = function()
		local current_tab = vim.fn.tabpagenr()
		vim.cmd("tabdo wincmd =")
		vim.cmd("tabnext " .. current_tab)
	end,
})

vim.api.nvim_create_autocmd('FileType', {
	pattern = { 'gitcommit', 'markdown' },
	callback = function()
		vim.opt_local.wrap = true
		vim.opt_local.spell = true
		vim.opt_local.textwidth = 80
	end,
})

-- go to last loc when opening a buffer
vim.api.nvim_create_autocmd("BufReadPost", {
	callback = function(event)
		local exclude = { "gitcommit" }
		local buf = event.buf
		if vim.tbl_contains(exclude, vim.bo[buf].filetype) or vim.b[buf].lazyvim_last_loc then
			return
		end
		vim.b[buf].lazyvim_last_loc = true
		local mark = vim.api.nvim_buf_get_mark(buf, '"')
		local lcount = vim.api.nvim_buf_line_count(buf)
		if mark[1] > 0 and mark[1] <= lcount then
			pcall(vim.api.nvim_win_set_cursor, 0, mark)
		end
	end,
})

vim.cmd [[
    augroup change_cursor
        au!
        au ExitPre * :set guicursor=a:hor90
    augroup END
]]

-- Fixes Autocomment
-- vim.api.nvim_create_autocmd({ 'BufWinEnter' }, {
-- 	callback = function()
-- 		vim.cmd 'set formatoptions-=cro'
-- 	end,
-- })