components/login/base_screen_handler_utils.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef COMPONENTS_LOGIN_BASE_SCREEN_HANDLER_UTILS_H_
   6 #define COMPONENTS_LOGIN_BASE_SCREEN_HANDLER_UTILS_H_
   7
   8 #include <cstddef>
   9 #include <string>
  10
  11 #include "base/callback.h"
  12 #include "base/logging.h"
  13 #include "base/strings/string16.h"
  14 #include "base/tuple.h"
  15 #include "base/values.h"
  16 #include "components/login/login_export.h"
  17
  18 namespace login {
  19
  20 typedef std::vector<std::string> StringList;
  21 typedef std::vector<base::string16> String16List;
  22
  23 template <typename T>
  24 struct LOGIN_EXPORT UnwrapConstRef {
  25   typedef T Type;
  26 };
  27
  28 template <typename T>
  29 struct LOGIN_EXPORT UnwrapConstRef<const T&> {
  30   typedef T Type;
  31 };
  32
  33 bool LOGIN_EXPORT ParseValue(const base::Value* value, bool* out_value);
  34 bool LOGIN_EXPORT ParseValue(const base::Value* value, int* out_value);
  35 bool LOGIN_EXPORT ParseValue(const base::Value* value, double* out_value);
  36 bool LOGIN_EXPORT ParseValue(const base::Value* value, std::string* out_value);
  37 bool LOGIN_EXPORT
  38     ParseValue(const base::Value* value, base::string16* out_value);
  39 bool LOGIN_EXPORT ParseValue(const base::Value* value,
  40                              const base::DictionaryValue** out_value);
  41 bool LOGIN_EXPORT ParseValue(const base::Value* value, StringList* out_value);
  42 bool LOGIN_EXPORT ParseValue(const base::Value* value, String16List* out_value);
  43
  44 template <typename T>
  45 inline bool GetArg(const base::ListValue* args, size_t index, T* out_value) {
  46   const base::Value* value;
  47   if (!args->Get(index, &value))
  48     return false;
  49   return ParseValue(value, out_value);
  50 }
  51
  52 base::FundamentalValue LOGIN_EXPORT MakeValue(bool v);
  53 base::FundamentalValue LOGIN_EXPORT MakeValue(int v);
  54 base::FundamentalValue LOGIN_EXPORT MakeValue(double v);
  55 base::StringValue LOGIN_EXPORT MakeValue(const std::string& v);
  56 base::StringValue LOGIN_EXPORT MakeValue(const base::string16& v);
  57
  58 template <typename T>
  59 inline const T& MakeValue(const T& v) {
  60   return v;
  61 }
  62
  63 template <typename Arg, size_t index>
  64 typename UnwrapConstRef<Arg>::Type ParseArg(const base::ListValue* args) {
  65   typename UnwrapConstRef<Arg>::Type parsed;
  66   CHECK(GetArg(args, index, &parsed));
  67   return parsed;
  68 }
  69
  70 template <typename... Args, size_t... Ns>
  71 inline void DispatchToCallback(const base::Callback<void(Args...)>& callback,
  72                                const base::ListValue* args,
  73                                IndexSequence<Ns...> indexes) {
  74   DCHECK(args);
  75   DCHECK_EQ(sizeof...(Args), args->GetSize());
  76
  77   callback.Run(ParseArg<Args, Ns>(args)...);
  78 }
  79
  80 template <typename... Args>
  81 void CallbackWrapper(const base::Callback<void(Args...)>& callback,
  82                      const base::ListValue* args) {
  83   DispatchToCallback(callback, args, MakeIndexSequence<sizeof...(Args)>());
  84 }
  85
  86
  87 }  // namespace login
  88
  89 #endif  // COMPONENTS_LOGIN_BASE_SCREEN_HANDLER_UTILS_H_