local M = {}

function M.config()
	local cmp_status_ok, cmp = pcall(require, 'cmp')
	if not cmp_status_ok then
		return
	end

	local snip_status_ok, luasnip = pcall(require, 'luasnip')
	if not snip_status_ok then
		return
	end

	local check_backspace = function()
		local col = vim.fn.col('.') - 1
		return col == 0 or vim.fn.getline('.'):sub(col, col):match('%s')
	end

	local kind_icons = {
		Text = '',
		Method = '',
		Function = '',
		Constructor = '',
		Field = 'ﰠ',
		Variable = '',
		Class = '',
		Interface = '',
		Module = '',
		Property = '',
		Unit = '',
		Value = '',
		Enum = '',
		Keyword = '',
		Snippet = '',
		Color = '',
		File = '',
		Reference = '',
		Folder = '',
		EnumMember = '',
		Constant = '',
		Struct = 'פּ',
		Event = '',
		Operator = '',
		TypeParameter = '',
	}

	cmp.setup({
		formatting = {
			fields = { 'menu', 'kind', 'abbr' },
			format = function(entry, item)
				local menu_icons = {
					nvim_lsp = 'λ',
					buffer = 'Ω',
					path = '🖫',
				}
				item.menu = menu_icons[entry.source.name]
				item.kind = kind_icons[item.kind]
				return item
			end,
		},
		snippet = {
			expand = function(args)
				luasnip.lsp_expand(args.body)
			end,
		},
		confirm_opts = {
			behavior = cmp.ConfirmBehavior.Replace,
			select = false,
		},
		experimental = {
			ghost_text = false,
		},
		window = {
			completion = {
				scrolloff = 1,
			},
		},
		preselect = cmp.PreselectMode.None,
		completion = {
			keyword_length = 1,
		},
		sources = {
			{ name = 'nvim_lsp', group_index = 1 },
			--{ name = "luasnip" },
			{ name = 'buffer', group_index = 2 },
			{ name = 'path' },
		},
		mapping = {
			['<C-k>'] = cmp.mapping.select_prev_item(),
			['<C-j>'] = cmp.mapping.select_next_item(),
			['<C-d>'] = cmp.mapping(cmp.mapping.scroll_docs(-1), { 'i', 'c' }),
			['<C-f>'] = cmp.mapping(cmp.mapping.scroll_docs(1), { 'i', 'c' }),
			['<C-Space>'] = cmp.mapping(cmp.mapping.complete(), { 'i', 'c' }),
			['<C-y>'] = cmp.config.disable,
			['<C-e>'] = cmp.mapping({
				i = cmp.mapping.abort(),
				c = cmp.mapping.close(),
			}),
			['<CR>'] = cmp.mapping.confirm({ select = false }),
			['<Tab>'] = cmp.mapping(function(fallback)
				if cmp.visible() then
					cmp.select_next_item()
				elseif luasnip.expandable() then
					luasnip.expand()
				elseif luasnip.expand_or_jumpable() then
					luasnip.expand_or_jump()
				elseif check_backspace() then
					fallback()
				else
					fallback()
				end
			end, {
				'i',
				's',
			}),
			['<S-Tab>'] = cmp.mapping(function(fallback)
				if cmp.visible() then
					cmp.select_prev_item()
				elseif luasnip.jumpable(-1) then
					luasnip.jump(-1)
				else
					fallback()
				end
			end, {
				'i',
				's',
			}),
		},
	})
end

return M