// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "chrome/common/trace_event_args_whitelist.h"

#include "base/bind.h"
#include "base/strings/pattern.h"
#include "base/strings/string_tokenizer.h"
#include "base/strings/string_util.h"

namespace {

struct WhitelistEntry {
  const char* category_name;
  const char* event_name;
  const char* const* arg_name_filter;
};

const char* const kInputLatencyAllowedArgs[] = {"data", nullptr};

const WhitelistEntry kEventArgsWhitelist[] = {
    {"__metadata", "thread_name", nullptr},
    {"ipc", "ChannelProxy::Context::OnDispatchMessage", nullptr},
    {"ipc", "SyncChannel::Send", nullptr},
    {"toplevel", "*", nullptr},
    {"latencyInfo", "*", kInputLatencyAllowedArgs},
    {nullptr, nullptr, nullptr}};

const char* kMetadataWhitelist[] = {
  "command_line",
  "config",
  "cpu-*",
  "field-trials",
  "gpu-*",
  "highres-ticks",
  "network-type",
  "num-cpus",
  "os-*",
  "physical-memory",
  "product-version",
  "user-agent"
};

}  // namespace

bool IsTraceArgumentNameWhitelisted(const char* const* granular_filter,
                                    const char* arg_name) {
  for (int i = 0; granular_filter[i] != nullptr; ++i) {
    if (base::MatchPattern(arg_name, granular_filter[i]))
      return true;
  }

  return false;
}

bool IsTraceEventArgsWhitelisted(
    const char* category_group_name,
    const char* event_name,
    base::trace_event::ArgumentNameFilterPredicate* arg_name_filter) {
  DCHECK(arg_name_filter);
  base::CStringTokenizer category_group_tokens(
      category_group_name, category_group_name + strlen(category_group_name),
      ",");
  while (category_group_tokens.GetNext()) {
    const std::string& category_group_token = category_group_tokens.token();
    for (int i = 0; kEventArgsWhitelist[i].category_name != nullptr; ++i) {
      const WhitelistEntry& whitelist_entry = kEventArgsWhitelist[i];
      DCHECK(whitelist_entry.event_name);

      if (base::MatchPattern(category_group_token.c_str(),
                             whitelist_entry.category_name) &&
          base::MatchPattern(event_name, whitelist_entry.event_name)) {
        if (whitelist_entry.arg_name_filter) {
          *arg_name_filter = base::Bind(&IsTraceArgumentNameWhitelisted,
                                        whitelist_entry.arg_name_filter);
        }
        return true;
      }
    }
  }

  return false;
}

bool IsMetadataWhitelisted(const std::string& metadata_name) {
  for (auto key : kMetadataWhitelist) {
    if (base::MatchPattern(metadata_name, key)) {
      return true;
    }
  }
  return false;
}