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

return {
    {
        "hrsh7th/nvim-cmp",
        config = function()
            local cmp = require("cmp")
            local cmp_under_comparator = require("cmp-under-comparator")
            local lspkind = require("lspkind")
            local luasnip = require("luasnip")

            cmp.setup({
                snippet = {
                    expand = function(args)
                        luasnip.lsp_expand(args.body)
                    end,
                },
                window = {
                    completion = cmp.config.window.bordered(),
                    documentation = cmp.config.window.bordered(),
                },
                mapping = cmp.mapping.preset.insert({
                    ["<A-p>"] = cmp.mapping.scroll_docs(-4),
                    ["<A-n>"] = cmp.mapping.scroll_docs(4),
                    ["<C-Space>"] = cmp.mapping.complete({}),
                    ["<C-e>"] = cmp.mapping.abort(),
                    ["<CR>"] = cmp.mapping.confirm({ select = true }),
                    ["<Tab>"] = cmp.mapping(function(fallback)
                        if cmp.visible() then
                            cmp.select_next_item()
                        elseif luasnip.expand_or_jumpable() then
                            luasnip.expand_or_jump()
                        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()
                        elseif luasnip.jumpable(-1) then
                            luasnip.jump(-1)
                        else
                            fallback()
                        end
                    end, { "i", "s" }),
                }),
                sources = cmp.config.sources({
                    { name = "nvim_lsp" },
                    { name = "luasnip" },
                }, {
                    { name = "buffer" },
                }),
                formatting = {
                    format = lspkind.cmp_format({
                        mode = "symbol",
                        maxwidth = 30,
                        ellipsis_char = "…",
                    }),
                },
            })

            cmp.setup.cmdline({ "/", "?" }, {
                mapping = cmp.mapping.preset.cmdline(),
                sources = {
                    { name = "buffer" },
                },
            })

            cmp.setup.cmdline(":", {
                mapping = cmp.mapping.preset.cmdline(),
                sources = cmp.config.sources({
                    { name = "path" },
                }, {
                    { name = "cmdline" },
                }),
            })
        end,
        dependencies = {
            "hrsh7th/cmp-buffer",
            "hrsh7th/cmp-path",
            "hrsh7th/cmp-nvim-lsp",
            "hrsh7th/cmp-nvim-lua",
            "hrsh7th/cmp-cmdline",
            "saadparwaiz1/cmp_luasnip",
            "L3MON4D3/LuaSnip",
            "lukas-reineke/cmp-under-comparator",
        },
    },
}