local M = {}

function M.config()
	local status_ok, null_ls = pcall(require, 'null-ls')
	if not status_ok then
		return
	end

	local augroup = vim.api.nvim_create_augroup('LspFormatting', {})
	null_ls.setup({
		debug = false,
		sources = {
			-- https://github.com/jose-elias-alvarez/null-ls.nvim/blob/main/doc/BUILTINS.md

			-- Lua

			-- sudo pacman -S stylua
			-- https://github.com/JohnnyMorganz/StyLua/releases
			null_ls.builtins.formatting.stylua,

			-- Python

			-- pip install black
			null_ls.builtins.formatting.black,

			-- pip install isort
			null_ls.builtins.formatting.isort,

			-- JavaScript / TypeScript

			-- sudo pacman -S prettierd
			-- sudo npm install -g @fsouza/prettierd
			null_ls.builtins.formatting.prettierd.with({
				disabled_filetypes = { 'html', 'markdown' },
				condition = function()
					-- https://github.com/jose-elias-alvarez/null-ls.nvim/discussions/1269
					return require('null-ls.utils').root_pattern(
						'.prettierrc',
						'.prettierrc.json',
						'.prettierrc.yml',
						'.prettierrc.yaml',
						'.prettierrc.json5',
						'.prettierrc.js',
						'.prettierrc.cjs',
						'.prettier.config.js',
						'.prettier.config.cjs',
						'.prettierrc.toml'
					)(vim.api.nvim_buf_get_name(0)) ~= nil
				end,
			}),

			-- sudo pacman -S eslint_d
			-- sudo npm install -g eslint_d
			null_ls.builtins.diagnostics.eslint_d.with({
				diagnostic_config = {
					virtual_text = false,
					severity_sort = true,
				},
				root_pattern = function()
					return require('null-ls.utils').root_pattern(
						-- file names copied from
						-- https://github.com/jose-elias-alvarez/null-ls.nvim/blob/main/lua/null-ls/builtins/diagnostics/eslint.lua
						'eslint.config.js',
						'.eslintrc',
						'.eslintrc.js',
						'.eslintrc.cjs',
						'.eslintrc.yaml',
						'.eslintrc.yml',
						'.eslintrc.json'
					)(vim.api.nvim_buf_get_name(0))
				end,
				condition = function()
					return require('null-ls.utils').root_pattern(
						-- file names copied from
						-- https://github.com/jose-elias-alvarez/null-ls.nvim/blob/main/lua/null-ls/builtins/diagnostics/eslint.lua
						'eslint.config.js',
						'.eslintrc',
						'.eslintrc.js',
						'.eslintrc.cjs',
						'.eslintrc.yaml',
						'.eslintrc.yml',
						'.eslintrc.json'
					)(vim.api.nvim_buf_get_name(0)) ~= nil
				end,
			}),
		},
		on_attach = function(client, bufnr)
			-- disable null-ls completion hints
			client.server_capabilities.completionProvider = false
			if client.supports_method('textDocument/formatting') then
				-- Format before save *only* in invsys

				local cwd = vim.fn.getcwd()
				-- substr the cwd starting at the last "/" character
				local cwd_name = string.sub(cwd, -cwd:reverse():find('/') + 1)
				if cwd_name == 'invsys' or cwd_name == 'invsys-b' then
					vim.api.nvim_clear_autocmds({ group = augroup, buffer = bufnr })
					vim.api.nvim_create_autocmd('BufWritePre', {
						group = augroup,
						buffer = bufnr,
						callback = function()
							vim.lsp.buf.format({ bufnr = bufnr })
						end,
					})
				end
			end
		end,
	})
end

return M