local present, cmp = pcall(require, "cmp")
if not present then return end

local has_words_before = function()
	local line, col = unpack(vim.api.nvim_win_get_cursor(0))
	return col ~= 0 and vim.api.nvim_buf_get_lines(0, line - 1, line, true)[1]:sub(col, col):match "%s" == nil
end

vim.opt.completeopt = "menuone,noselect"

-- nvim-cmp setup
cmp.setup {
	window = {
		completion = {
			border = { "╭", "─", "╮", "│", "╯", "─", "╰", "│" },
			winhighlight = "Normal:CmpPmenu,FloatBorder:CmpBorder,CursorLine:PmenuSel,Search:None",
		},
		documentation = {
			border = { "╭", "─", "╮", "│", "╯", "─", "╰", "│" },
			winhighlight = "Normal:CmpPmenu,FloatBorder:CmpBorder,CursorLine:PmenuSel,Search:None",
		},
	},
	experimental = {
		ghost_text = true,
	},
	snippet = {
		expand = function(args) require("luasnip").lsp_expand(args.body) end,
	},
	mapping = {
		["<C-n>"] = cmp.mapping(function(fallback)
			if require("luasnip").expand_or_jumpable() then
				require("luasnip").expand_or_jump()
			else
				fallback()
			end
		end, { "i", "s" }),
		["<C-p>"] = cmp.mapping(function(fallback)
			if require("luasnip").jumpable(-1) then
				require("luasnip").jump(-1)
			else
				fallback()
			end
		end, { "i", "s" }),
		["<C-d>"] = cmp.mapping.scroll_docs(-4),
		["<C-f>"] = cmp.mapping.scroll_docs(4),
		["<C-Space>"] = cmp.mapping.complete(),
		["<C-e>"] = cmp.mapping.close(),
		["<CR>"] = cmp.mapping.confirm {
			behavior = cmp.ConfirmBehavior.Replace,
			select = false,
		},
		["<Tab>"] = cmp.mapping(function(fallback)
			if cmp.visible() then
				cmp.select_next_item()
			elseif has_words_before() then
				cmp.complete()
			else
				fallback()
			end
		end, { "i", "s" }),
		["<S-Tab>"] = cmp.mapping(function(fallback)
			if cmp.visible() then
				cmp.select_prev_item()
			else
				fallback()
			end
		end, { "i", "s" }),
	},
	sources = {
		{ name = "nvim_lua" },
		{ name = "nvim_lsp" },
		{ name = "buffer" },
		{ name = "path" },
	},
	formatting = {
		format = function(entry, vim_item)
			local icons = {
				Text = "",
				Method = "",
				Function = "",
				Constructor = "",
				Field = "ﰠ",
				Variable = "",
				Class = "ﴯ",
				Interface = "",
				Module = "",
				Property = "ﰠ",
				Unit = "塞",
				Value = "",
				Enum = "",
				Keyword = "",
				Snippet = "",
				Color = "",
				File = "",
				Reference = "",
				Folder = "",
				EnumMember = "",
				Constant = "",
				Struct = "פּ",
				Event = "",
				Operator = "",
				TypeParameter = "",
			}
			vim_item.kind = string.format("%s %s", icons[vim_item.kind], vim_item.kind)

			vim_item.menu = ({
				nvim_lsp = "[LSP]",
				nvim_lua = "[Lua]",
				buffer = "[BUF]",
			})[entry.source.name]

			return vim_item
		end,
	},
}