local M = {}

function M.setup(opts)
  opts = opts or {}
  local ns = vim.api.nvim_create_namespace("tiny-lightbulb")
  local group = vim.api.nvim_create_augroup("tiny-lightbulb", { clear = true })
  local gen = 0

  local function clear()
    gen = gen + 1
    vim.api.nvim_buf_clear_namespace(0, ns, 0, -1)
  end

  vim.api.nvim_create_autocmd({ "CursorHold", "CursorHoldI" }, {
    group = group,
    callback = function()
      local buf, lnum = vim.api.nvim_get_current_buf(), vim.fn.line(".") - 1
      clear()
      if #vim.lsp.get_clients({ bufnr = buf, method = "textDocument/codeAction" }) == 0 then
        return
      end
      local id = gen
      vim.lsp.buf_request(buf, "textDocument/codeAction", {
        textDocument = { uri = vim.uri_from_bufnr(buf) },
        range = { start = { line = lnum, character = 0 }, ["end"] = { line = lnum, character = 0 } },
        context = { diagnostics = vim.diagnostic.get(buf, { lnum = lnum }) },
      }, function(err, results)
        if id == gen and not err and results and results[1] and vim.api.nvim_buf_is_valid(buf) then
          vim.api.nvim_buf_set_extmark(buf, ns, lnum, 0, {
            sign_text = opts.sign or "💡",
            sign_hl_group = opts.hl or "DiagnosticWarn",
          })
        end
      end)
    end,
  })

  vim.api.nvim_create_autocmd({ "CursorMoved", "CursorMovedI", "InsertEnter" }, {
    group = group,
    callback = clear,
  })
end

return M