function setup_keymap_lsp()
    -- -- Global mappings.
    -- -- See `:help vim.diagnostic.*` for documentation on any of the below functions
    -- vim.keymap.set("n", "<leader>e", vim.diagnostic.open_float)
    -- vim.keymap.set("n", "[d", vim.diagnostic.goto_prev)
    -- vim.keymap.set("n", "]d", vim.diagnostic.goto_next)
    -- vim.keymap.set("n", "<leader>q", vim.diagnostic.setloclist)

    vim.api.nvim_create_autocmd("LspAttach", {
        group = vim.api.nvim_create_augroup("UserLspConfig", {}),
        callback = function(ev)
            -- Enable completion triggered by <c-x><c-o>
            vim.bo[ev.buf].omnifunc = "v:lua.vim.lsp.omnifunc"

            -- Buffer local mappings.
            -- See `:help vim.lsp.*` for documentation on any of the below functions
            local opts = { buffer = ev.buf }
            vim.keymap.set("n", "gt", vim.lsp.buf.type_definition, opts)
            vim.keymap.set("n", "gD", vim.lsp.buf.declaration, opts)
            vim.keymap.set("n", "gd", vim.lsp.buf.definition, opts)
            vim.keymap.set("n", "gi", vim.lsp.buf.implementation, opts)
            vim.keymap.set("n", "gr", vim.lsp.buf.references, opts)
            vim.keymap.set("n", "K", vim.lsp.buf.hover, opts)
            vim.keymap.set("n", "<C-k>", vim.lsp.buf.signature_help, opts)
            vim.keymap.set("n", "<leader>wa", vim.lsp.buf.add_workspace_folder, opts)
            vim.keymap.set("n", "<leader>wr", vim.lsp.buf.remove_workspace_folder, opts)
            vim.keymap.set("n", "<leader>wl", function()
                print(vim.inspect(vim.lsp.buf.list_workspace_folders()))
            end, opts)
            vim.keymap.set("n", "gR", vim.lsp.buf.rename, opts)
            vim.keymap.set({ "n", "v" }, "ga", vim.lsp.buf.code_action, opts)
            vim.keymap.set("n", "g=", function()
                vim.lsp.buf.format { async = true }
            end, opts)
        end,
    })
end

local lua_ls_opts = {
    settings = {
        Lua = {
            runtime = {
                -- Tell the language server which version of Lua you're using (most likely LuaJIT in the case of Neovim)
                version = "LuaJIT",
            },
            diagnostics = {
                -- Get the language server to recognize the `vim` global
                globals = { "vim" },
            },
            workspace = {
                -- Make the server aware of Neovim runtime files
                library = vim.api.nvim_get_runtime_file("", true),
            },
            -- Do not send telemetry data containing a randomized but unique identifier
            telemetry = {
                enable = false,
            },
        },
    },
}

return {
    {
        "neovim/nvim-lspconfig",
        enabled = custom.full_feature,
        dependencies = {
            "hrsh7th/nvim-cmp",
            "hrsh7th/cmp-nvim-lsp",
            "hrsh7th/cmp-buffer",
            "hrsh7th/cmp-path",
            "hrsh7th/cmp-cmdline",
            "L3MON4D3/LuaSnip",

            "williamboman/mason.nvim",
            "williamboman/mason-lspconfig.nvim",
            "mfussenegger/nvim-lint",
            "mhartington/formatter.nvim",
        },
        event = { "BufReadPre", "BufNewFile", "VeryLazy" },
        cmd = { "LspInfo", "LspInstall", "LspUninstall" },
        config = function (_, opts)
            local mason = require("mason")
            local mason_lsp = require("mason-lspconfig")
            local luasnip = require("luasnip")
            local cmp = require("cmp")

            mason.setup()
            mason_lsp.setup()
            mason_lsp.setup_handlers {
                function (server_name) -- default handler (optional)
                    require("lspconfig")[server_name].setup {}
                end,

                ["lua_ls"] = function ()
                    require("lspconfig")["lua_ls"].setup(lua_ls_opts)
                end
            }

            cmp.setup({
                snippet = {
                    expand = function(args)
                        luasnip.lsp_expand(args.body)
                    end,
                },
                mapping = cmp.mapping.preset.insert({
                    ["<C-b>"] = cmp.mapping.scroll_docs(-4),
                    ["<C-f>"] = cmp.mapping.scroll_docs(4),
                    ["<C-Space>"] = cmp.mapping.complete(),
                    ["<C-e>"] = cmp.mapping.abort(),
                    ["<tab>"] = cmp.mapping.confirm({ select = true }),
                }),
                sources = cmp.config.sources({
                    { name = "nvim_lsp" },
                    { name = "buffer" },
                    { name = "luasnip" },
                }),
            })
            cmp.setup.cmdline(":", {
                mapping = cmp.mapping.preset.cmdline(),
                sources = cmp.config.sources({
                    { name = "path" }
                }, {
                    { name = "cmdline" }
                })
            })

            setup_keymap_lsp()
        end,
        keys = {
            { "gs", "<cmd>LspStart<cr>", mode = "n" },
            { "gS", "<cmd>LspStop<cr>", mode = "n" },
            { "gI", "<cmd>LspInfo<cr>", mode = "n" },
            { "ge", vim.diagnostic.open_float, mode = "n" },
            { "gp", vim.diagnostic.goto_prev, mode = "n" },
            { "gn", vim.diagnostic.goto_next, mode = "n" },
            { "gq", vim.diagnostic.setloclist, mode = "n" }
        },
    },
    {
        "folke/trouble.nvim",
        dependencies = { "nvim-tree/nvim-web-devicons" },
        event = "VeryLazy",
        keys = {
            { "<leader>xx", "<cmd>TroubleToggle<cr>", mode = "n" },
            { "<leader>xw", "<cmd>TroubleToggle workspace_diagnostics<cr>", mode = "n" },
            { "<leader>xd", "<cmd>TroubleToggle document_diagnostics<cr>", mode = "n" },
            { "<leader>xq", "<cmd>TroubleToggle quickfix<cr>", mode = "n" },
            { "<leader>xl", "<cmd>TroubleToggle loclist<cr>", mode = "n" },
            { "<leader>xr", "<cmd>TroubleToggle lsp_references<cr>", mode = "n" },
        },
        opts = { },
    },
}