local function isempty(s)
  return s == nil or s == ""
end

local function use_if_defined(val, fallback)
  return val ~= nil and val or fallback
end

return {
  on_attach = function()
    local conda_prefix = os.getenv("CONDA_PREFIX")
    if not isempty(conda_prefix) then
        vim.g.python_host_prog = use_if_defined(vim.g.python_host_prog, conda_prefix .. "/bin/python")
        vim.g.python3_host_prog = use_if_defined(vim.g.python3_host_prog, conda_prefix .. "/bin/python")
    else
        vim.g.python_host_prog = use_if_defined(vim.g.python_host_prog, "python")
        vim.g.python3_host_prog = use_if_defined(vim.g.python3_host_prog, "python3")
    end
    G.api.nvim_create_user_command('R', function()
      G.cmd [[set splitbelow]]
      G.cmd [[sp]]
      G.cmd [[term python3 %]]
      G.cmd [[resize 10]]
      G.cmd [[startinsert]]
    end, {})
  end
}