// Copyright (c) 2014 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 "content/common/content_switches_internal.h"

#include <string>

#include "base/command_line.h"
#include "base/metrics/field_trial.h"
#include "base/metrics/field_trial_params.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/string_split.h"
#include "base/strings/string_util.h"
#include "base/strings/stringprintf.h"
#include "base/strings/utf_string_conversions.h"
#include "build/build_config.h"
#include "content/public/common/content_switches.h"
#include "content/public/common/use_zoom_for_dsf_policy.h"

#if defined(OS_ANDROID)
#include "base/debug/debugger.h"
#include "base/feature_list.h"
#endif

#if defined(OS_POSIX) && !defined(OS_ANDROID)
#include <signal.h>
static void SigUSR1Handler(int signal) {}
#endif

#if defined(OS_WIN)
#include "base/win/windows_version.h"
#endif

namespace content {

namespace {

const base::Feature kSavePreviousDocumentResources{
    "SavePreviousDocumentResources", base::FEATURE_DISABLED_BY_DEFAULT};

#if defined(OS_WIN)

base::string16 ToNativeString(base::StringPiece string) {
  return base::ASCIIToUTF16(string);
}

std::string FromNativeString(base::StringPiece16 string) {
  return base::UTF16ToASCII(string);
}

#else  // defined(OS_WIN)

std::string ToNativeString(const std::string& string) {
  return string;
}

std::string FromNativeString(const std::string& string) {
  return string;
}

#endif  // defined(OS_WIN)

}  // namespace

bool IsPinchToZoomEnabled() {
  const base::CommandLine& command_line =
      *base::CommandLine::ForCurrentProcess();

  // Enable pinch everywhere unless it's been explicitly disabled.
  return !command_line.HasSwitch(switches::kDisablePinch);
}

V8CacheOptions GetV8CacheOptions() {
  const base::CommandLine& command_line =
      *base::CommandLine::ForCurrentProcess();
  std::string v8_cache_options =
      command_line.GetSwitchValueASCII(switches::kV8CacheOptions);
  if (v8_cache_options.empty())
    v8_cache_options = base::FieldTrialList::FindFullName("V8CacheOptions");
  if (v8_cache_options == "none") {
    return V8_CACHE_OPTIONS_NONE;
  } else if (v8_cache_options == "code") {
    return V8_CACHE_OPTIONS_CODE;
  } else {
    return V8_CACHE_OPTIONS_DEFAULT;
  }
}

SavePreviousDocumentResources GetSavePreviousDocumentResources() {
  const base::CommandLine& command_line =
      *base::CommandLine::ForCurrentProcess();
  std::string save_previous_document_resources =
      command_line.GetSwitchValueASCII(
          switches::kSavePreviousDocumentResources);
  if (save_previous_document_resources == "never")
    return SavePreviousDocumentResources::NEVER;
  if (save_previous_document_resources == "onDOMContentLoaded")
    return SavePreviousDocumentResources::UNTIL_ON_DOM_CONTENT_LOADED;
  if (save_previous_document_resources == "onload")
    return SavePreviousDocumentResources::UNTIL_ON_LOAD;
  // The command line, which is set by the user, takes priority. Otherwise,
  // fall back to the field trial.
  std::string until = base::GetFieldTrialParamValueByFeature(
      kSavePreviousDocumentResources, "until");
  if (until == "onDOMContentLoaded")
    return SavePreviousDocumentResources::UNTIL_ON_DOM_CONTENT_LOADED;
  if (until == "onload")
    return SavePreviousDocumentResources::UNTIL_ON_LOAD;
  return SavePreviousDocumentResources::NEVER;
}

void WaitForDebugger(const std::string& label) {
#if defined(OS_WIN)
#if defined(GOOGLE_CHROME_BUILD)
  std::string title = "Google Chrome";
#else   // CHROMIUM_BUILD
  std::string title = "Chromium";
#endif  // CHROMIUM_BUILD
  title += " ";
  title += label;  // makes attaching to process easier
  std::string message = label;
  message += " starting with pid: ";
  message += base::IntToString(base::GetCurrentProcId());
  ::MessageBox(NULL, base::UTF8ToWide(message).c_str(),
               base::UTF8ToWide(title).c_str(), MB_OK | MB_SETFOREGROUND);
#elif defined(OS_POSIX)
#if defined(OS_ANDROID)
  LOG(ERROR) << label << " waiting for GDB.";
  // Wait 24 hours for a debugger to be attached to the current process.
  base::debug::WaitForDebugger(24 * 60 * 60, true);
#else
  // TODO(playmobil): In the long term, overriding this flag doesn't seem
  // right, either use our own flag or open a dialog we can use.
  // This is just to ease debugging in the interim.
  LOG(ERROR) << label << " (" << getpid()
             << ") paused waiting for debugger to attach. "
             << "Send SIGUSR1 to unpause.";
  // Install a signal handler so that pause can be woken.
  struct sigaction sa;
  memset(&sa, 0, sizeof(sa));
  sa.sa_handler = SigUSR1Handler;
  sigaction(SIGUSR1, &sa, nullptr);

  pause();
#endif  // defined(OS_ANDROID)
#endif  // defined(OS_POSIX)
}

std::vector<std::string> FeaturesFromSwitch(
    const base::CommandLine& command_line,
    const char* switch_name) {
  using NativeString = base::CommandLine::StringType;
  using NativeStringPiece = base::BasicStringPiece<NativeString>;

  std::vector<std::string> features;
  if (!command_line.HasSwitch(switch_name))
    return features;

  // Store prefix as native string to avoid conversions for every arg.
  // (No string copies for the args that don't match the prefix.)
  NativeString prefix =
      ToNativeString(base::StringPrintf("--%s=", switch_name));
  for (NativeStringPiece arg : command_line.argv()) {
    // Switch names are case insensitive on Windows, but base::CommandLine has
    // already made them lowercase when building argv().
    if (!StartsWith(arg, prefix, base::CompareCase::SENSITIVE))
      continue;
    arg.remove_prefix(prefix.size());
    if (!IsStringASCII(arg))
      continue;
    auto vals = SplitString(FromNativeString(arg.as_string()), ",",
                            base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
    features.insert(features.end(), vals.begin(), vals.end());
  }
  return features;
}

} // namespace content