local M = {}

--- @type LDH.configFull
M.DEFAULT = {
  throttle = 150,
  navigation = {
    notify_end = true,
    open_folds = true,
    set_jump = true,
  },
  enable = {
    modes = { "n", "c" }, -- c is included so highlights don't disappear when typing commands
    ---@diagnostic disable-next-line: unused-local
    buffers = function(buf)
      return true
    end,
  },
}

--- @type LDH.configFull
M._cur = vim.deepcopy(M.DEFAULT)

--- @return LDH.configFull
function M.get()
  return M._cur
end

--- @param opts LDH.config
function M.validate(opts)
  --- @param o table
  --- @param schema table
  --- @param path string[]
  local function go(o, schema, path)
    for k, v in pairs(o) do
      local cur_path = table.concat(path, ".") .. "." .. k
      if schema[k] == nil then
        error("Unexpected field at " .. cur_path)
      end
      if type(v) ~= type(schema[k]) then
        error("Invalid type for field " .. cur_path .. " (expected " .. type(schema[k]) .. ", got " .. type(v) .. ")")
      elseif type(v) == "table" then
        path[#path + 1] = k
        go(v, schema[k], path)
        path[#path] = nil
      end
    end
  end
  go(opts, M.DEFAULT, {})
end

--- @param opts LDH.config
function M.update(opts)
  local ok, err = pcall(M.validate, opts)
  if not ok then
    error("Config validation error: " .. err)
  end
  M._cur = vim.tbl_deep_extend("force", M.get(), opts)
end

--- @param opts LDH.config
function M.set(opts)
  local ok, err = pcall(M.validate, opts)
  if not ok then
    error("Config validation error: " .. err)
  end
  M._cur = vim.tbl_deep_extend("force", M.DEFAULT, opts)
end

return M