nvim/lua/plugins/lsp/ui.lua

local M = {}

function M.setup()
    -- Signs
    local signs = { Error = "", Warn = "", Hint = "", Info = "" }
    for type, icon in pairs(signs) do
        local hl = "DiagnosticSign" .. type
        vim.fn.sign_define(hl, { text = icon, texthl = hl, numhl = hl })
    end

    -- Floating window borders
    local border = {
        { "╭", "FloatBorder" },
        { "─", "FloatBorder" },
        { "╮", "FloatBorder" },
        { "│", "FloatBorder" },
        { "╯", "FloatBorder" },
        { "─", "FloatBorder" },
        { "╰", "FloatBorder" },
        { "│", "FloatBorder" },
    }
    local orig_util_open_floating_preview = vim.lsp.util.open_floating_preview
    function vim.lsp.util.open_floating_preview(contents, syntax, opts, ...)
        opts = opts or {}
        opts.border = opts.border or border
        return orig_util_open_floating_preview(contents, syntax, opts, ...)
    end
end

function M.on_attach(client, bufnr)
    -- Highlight references
    -- if client.server_capabilities.documentHighlightProvider then
    --     vim.api.nvim_create_augroup("lsp_document_highlight", {
    --         clear = false,
    --     })
    --     vim.api.nvim_clear_autocmds({
    --         group = "lsp_document_highlight",
    --         buffer = bufnr,
    --     })
    --     -- vim.api.nvim_create_autocmd({ "CursorHold", "CursorHoldI" }, {
    --     --     group = "lsp_document_highlight",
    --     --     buffer = bufnr,
    --     --     callback = vim.lsp.buf.document_highlight,
    --     -- })
    --     -- vim.api.nvim_create_autocmd("CursorMoved", {
    --     --     group = "lsp_document_highlight",
    --     --     buffer = bufnr,
    --     --     callback = vim.lsp.buf.clear_references,
    --     -- })
    -- end
end

return M