// Copyright (c) 2013 The Chromium Embedded Framework 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 "libcef/browser/request_context_impl.h"
#include "libcef/browser/browser_context_impl.h"
#include "libcef/browser/browser_context_proxy.h"
#include "libcef/browser/content_browser_client.h"
#include "libcef/browser/context.h"
#include "libcef/browser/cookie_manager_impl.h"
#include "libcef/browser/thread_util.h"
#include "libcef/common/values_impl.h"

#include "base/atomic_sequence_num.h"
#include "base/logging.h"
#include "base/strings/stringprintf.h"
#include "components/prefs/pref_service.h"
#include "content/public/browser/plugin_service.h"
#include "content/public/browser/ssl_host_state_delegate.h"
#include "net/http/http_cache.h"
#include "net/http/http_transaction_factory.h"

using content::BrowserThread;

namespace {

base::StaticAtomicSequenceNumber g_next_id;

const char* GetTypeString(base::Value::Type type) {
  switch (type) {
    case base::Value::TYPE_NULL:
      return "NULL";
    case base::Value::TYPE_BOOLEAN:
      return "BOOLEAN";
    case base::Value::TYPE_INTEGER:
      return "INTEGER";
    case base::Value::TYPE_DOUBLE:
      return "DOUBLE";
    case base::Value::TYPE_STRING:
      return "STRING";
    case base::Value::TYPE_BINARY:
      return "BINARY";
    case base::Value::TYPE_DICTIONARY:
      return "DICTIONARY";
    case base::Value::TYPE_LIST:
      return "LIST";
  }

  NOTREACHED();
  return "UNKNOWN";
}

// Helper for HostResolver::Resolve.
struct ResolveHostHelper {
  explicit ResolveHostHelper(CefRefPtr<CefResolveCallback> callback)
      : callback_(callback) {
  }

  void OnResolveCompleted(int result) {
    std::vector<CefString> resolved_ips;

    net::AddressList::const_iterator iter = address_list_.begin();
    for (; iter != address_list_.end(); ++iter)
      resolved_ips.push_back(iter->ToStringWithoutPort());

    CEF_POST_TASK(CEF_UIT,
        base::Bind(&CefResolveCallback::OnResolveCompleted, callback_.get(),
                   static_cast<cef_errorcode_t>(result), resolved_ips));

    delete this;
  }

  CefRefPtr<CefResolveCallback> callback_;
  net::AddressList address_list_;
};

}  // namespace


// CefBrowserContext

// static
CefRefPtr<CefRequestContext> CefRequestContext::GetGlobalContext() {
  // Verify that the context is in a valid state.
  if (!CONTEXT_STATE_VALID()) {
    NOTREACHED() << "context not valid";
    return NULL;
  }

  return CefRequestContextImpl::GetForBrowserContext(
      CefContentBrowserClient::Get()->browser_context());
}

// static
CefRefPtr<CefRequestContext> CefRequestContext::CreateContext(
    const CefRequestContextSettings& settings,
    CefRefPtr<CefRequestContextHandler> handler) {
  // Verify that the context is in a valid state.
  if (!CONTEXT_STATE_VALID()) {
    NOTREACHED() << "context not valid";
    return NULL;
  }

  return new CefRequestContextImpl(settings, handler);
}

// static
CefRefPtr<CefRequestContext> CefRequestContext::CreateContext(
    CefRefPtr<CefRequestContext> other,
    CefRefPtr<CefRequestContextHandler> handler) {
  // Verify that the context is in a valid state.
  if (!CONTEXT_STATE_VALID()) {
    NOTREACHED() << "context not valid";
    return NULL;
  }

  if (!other.get())
    return NULL;

  return new CefRequestContextImpl(
      static_cast<CefRequestContextImpl*>(other.get()), handler);
}


// CefBrowserContextImpl

CefRequestContextImpl::~CefRequestContextImpl() {
}

// static
CefRefPtr<CefRequestContextImpl> CefRequestContextImpl::GetForRequestContext(
      CefRefPtr<CefRequestContext> request_context) {
   if (request_context.get()) {
    // Use the context from the provided CefRequestContext.
    return static_cast<CefRequestContextImpl*>(request_context.get());
  }
  
  // Use the global context.
  scoped_refptr<CefBrowserContext> browser_context =
      CefContentBrowserClient::Get()->browser_context();
  return GetForBrowserContext(browser_context);
}

// static
CefRefPtr<CefRequestContextImpl> CefRequestContextImpl::GetForBrowserContext(
      scoped_refptr<CefBrowserContext> browser_context) {
  DCHECK(browser_context.get());
  return new CefRequestContextImpl(browser_context);
}

scoped_refptr<CefBrowserContext> CefRequestContextImpl::GetBrowserContext() {
  CEF_REQUIRE_UIT();

  if (!browser_context_) {
    scoped_refptr<CefBrowserContextImpl> parent;

    if (other_.get()) {
      // Share storage with |other_|.
      parent = CefBrowserContextImpl::GetForContext(
          other_->GetBrowserContext().get());
    }

    if (!parent.get()) {
      const base::FilePath& cache_path =
          base::FilePath(CefString(&settings_.cache_path));
      if (!cache_path.empty()) {
        // Check if a CefBrowserContextImpl is already globally registered for
        // the specified cache path. If so then use it.
        parent = CefBrowserContextImpl::GetForCachePath(cache_path);
      }
    }

    if (!parent.get()) {
      // Create a new CefBrowserContextImpl instance. If the cache path is non-
      // empty then this new instance will become the globally registered
      // CefBrowserContextImpl for that path. Otherwise, this new instance will
      // be a completely isolated "incongento mode" context.
      parent = new CefBrowserContextImpl(settings_);
      parent->Initialize();
    }

    // The parent's settings may be different. Force our settings to match the
    // parent.
    settings_ = parent->GetSettings();

    if (handler_.get()) {
      // Use a proxy that will execute handler callbacks where appropriate and
      // otherwise forward all requests to the parent implementation.
      browser_context_ = new CefBrowserContextProxy(handler_, parent);
      browser_context_->Initialize();
    } else {
      // Use the parent implementation directly.
      browser_context_ = parent;
    }

    request_context_impl_ = parent->request_context().get();
    DCHECK(request_context_impl_);

    if (handler_.get()) {
      // Keep the handler alive until the associated request context is
      // destroyed.
      request_context_impl_->AddHandler(handler_);
    }
  }

  if (!request_context_impl_) {
    request_context_impl_ =
        CefBrowserContextImpl::GetForContext(browser_context_.get())->
            request_context().get();
    DCHECK(request_context_impl_);
  }

  if (other_.get()) {
    // Clear the reference to |other_| after setting |request_context_impl_|.
    // This is the reverse order of checks in IsSharedWith().
    other_ = NULL;
  }

  return browser_context_;
}

void CefRequestContextImpl::GetBrowserContext(
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    const BrowserContextCallback& callback) {
  if (!task_runner.get())
    task_runner = base::MessageLoop::current()->task_runner();
  GetBrowserContextOnUIThread(task_runner, callback);
}

void CefRequestContextImpl::GetRequestContextImpl(
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    const RequestContextCallback& callback) {
  if (!task_runner.get())
    task_runner = base::MessageLoop::current()->task_runner();
  if (request_context_impl_) {
    // The browser context already exists.
    DCHECK(browser_context_.get());
    GetRequestContextImplOnIOThread(task_runner, callback, browser_context_);
  } else {
    // Need to initialize the browser context first.
    GetBrowserContextOnUIThread(
        BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
        base::Bind(&CefRequestContextImpl::GetRequestContextImplOnIOThread,
                   this, task_runner, callback));
  }
}

bool CefRequestContextImpl::IsSame(CefRefPtr<CefRequestContext> other) {
  CefRequestContextImpl* other_impl =
      static_cast<CefRequestContextImpl*>(other.get());
  if (!other_impl)
    return false;

  // Compare CefBrowserContext pointers if one has been associated.
  if (browser_context_ && other_impl->browser_context_)
    return (browser_context_ == other_impl->browser_context_);
  else if (browser_context_ || other_impl->browser_context_)
    return false;

  // Otherwise compare unique IDs.
  return (unique_id_ == other_impl->unique_id_);
}

bool CefRequestContextImpl::IsSharingWith(CefRefPtr<CefRequestContext> other) {
  CefRequestContextImpl* other_impl =
      static_cast<CefRequestContextImpl*>(other.get());
  if (!other_impl)
    return false;

  if (IsSame(other))
    return true;

  CefRefPtr<CefRequestContext> pending_other = other_;
  if (pending_other.get()) {
    // This object is not initialized but we know what context this object will
    // share with. Compare to that other context instead.
    return pending_other->IsSharingWith(other);
  }

  pending_other = other_impl->other_;
  if (pending_other.get()) {
    // The other object is not initialized but we know what context that object
    // will share with. Compare to that other context instead.
    return pending_other->IsSharingWith(this);
  }

  if (request_context_impl_ && other_impl->request_context_impl_) {
    // Both objects are initialized. Compare the request context objects.
    return (request_context_impl_ == other_impl->request_context_impl_);
  }

  // This or the other object is not initialized. Compare the cache path values.
  // If both are non-empty and the same then they'll share the same storage.
  if (settings_.cache_path.length > 0 &&
      other_impl->settings_.cache_path.length > 0) {
    return (base::FilePath(CefString(&settings_.cache_path)) ==
            base::FilePath(CefString(&other_impl->settings_.cache_path)));
  }

  return false;
}

bool CefRequestContextImpl::IsGlobal() {
  return (browser_context_ ==
          CefContentBrowserClient::Get()->browser_context());
}

CefRefPtr<CefRequestContextHandler> CefRequestContextImpl::GetHandler() {
  return handler_;
}

CefString CefRequestContextImpl::GetCachePath() {
  return CefString(&settings_.cache_path);
}

CefRefPtr<CefCookieManager> CefRequestContextImpl::GetDefaultCookieManager(
    CefRefPtr<CefCompletionCallback> callback) {
  CefRefPtr<CefCookieManagerImpl> cookie_manager = new CefCookieManagerImpl();
  cookie_manager->Initialize(this, CefString(), false, callback);
  return cookie_manager.get();
}

bool CefRequestContextImpl::RegisterSchemeHandlerFactory(
    const CefString& scheme_name,
    const CefString& domain_name,
    CefRefPtr<CefSchemeHandlerFactory> factory) {
  GetRequestContextImpl(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
      base::Bind(&CefRequestContextImpl::RegisterSchemeHandlerFactoryInternal,
                 this, scheme_name, domain_name, factory));
  return true;
}

bool CefRequestContextImpl::ClearSchemeHandlerFactories() {
  GetRequestContextImpl(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
      base::Bind(&CefRequestContextImpl::ClearSchemeHandlerFactoriesInternal,
                 this));
  return true;
}

void CefRequestContextImpl::PurgePluginListCache(bool reload_pages) {
  GetBrowserContext(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI),
      base::Bind(&CefRequestContextImpl::PurgePluginListCacheInternal,
                 this, reload_pages));
}

bool CefRequestContextImpl::HasPreference(const CefString& name) {
  // Verify that this method is being called on the UI thread.
  if (!CEF_CURRENTLY_ON_UIT()) {
    NOTREACHED() << "called on invalid thread";
    return false;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  PrefService* pref_service = browser_context_->GetPrefs();
  return (pref_service->FindPreference(name) != NULL);
}

CefRefPtr<CefValue> CefRequestContextImpl::GetPreference(
    const CefString& name) {
  // Verify that this method is being called on the UI thread.
  if (!CEF_CURRENTLY_ON_UIT()) {
    NOTREACHED() << "called on invalid thread";
    return NULL;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  PrefService* pref_service = browser_context_->GetPrefs();
  const PrefService::Preference* pref = pref_service->FindPreference(name);
  if (!pref)
    return NULL;
  return new CefValueImpl(pref->GetValue()->DeepCopy());
}

CefRefPtr<CefDictionaryValue> CefRequestContextImpl::GetAllPreferences(
    bool include_defaults) {
  // Verify that this method is being called on the UI thread.
  if (!CEF_CURRENTLY_ON_UIT()) {
    NOTREACHED() << "called on invalid thread";
    return NULL;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  PrefService* pref_service = browser_context_->GetPrefs();

  std::unique_ptr<base::DictionaryValue> values;
  if (include_defaults)
    values = pref_service->GetPreferenceValues();
  else
    values = pref_service->GetPreferenceValuesOmitDefaults();

  // CefDictionaryValueImpl takes ownership of |values|.
  return new CefDictionaryValueImpl(values.release(), true, false);
}

bool CefRequestContextImpl::CanSetPreference(const CefString& name) {
  // Verify that this method is being called on the UI thread.
  if (!CEF_CURRENTLY_ON_UIT()) {
    NOTREACHED() << "called on invalid thread";
    return false;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  PrefService* pref_service = browser_context_->GetPrefs();
  const PrefService::Preference* pref = pref_service->FindPreference(name);
  return (pref && pref->IsUserModifiable());
}

bool CefRequestContextImpl::SetPreference(const CefString& name,
                                          CefRefPtr<CefValue> value,
                                          CefString& error) {
  // Verify that this method is being called on the UI thread.
  if (!CEF_CURRENTLY_ON_UIT()) {
    NOTREACHED() << "called on invalid thread";
    return false;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  PrefService* pref_service = browser_context_->GetPrefs();

  // The below validation logic should match PrefService::SetUserPrefValue.

  const PrefService::Preference* pref = pref_service->FindPreference(name);
  if (!pref) {
    error = "Trying to modify an unregistered preference";
    return false;
  }

  if (!pref->IsUserModifiable()) {
    error = "Trying to modify a preference that is not user modifiable";
    return false;
  }

  if (!value.get()) {
    // Reset the preference to its default value.
    pref_service->ClearPref(name);
    return true;
  }

  if (!value->IsValid()) {
    error = "A valid value is required";
    return false;
  }

  CefValueImpl* impl = static_cast<CefValueImpl*>(value.get());

  CefValueImpl::ScopedLockedValue scoped_locked_value(impl);
  base::Value* impl_value = impl->GetValueUnsafe();

  if (pref->GetType() != impl_value->GetType()) {
    error = base::StringPrintf(
        "Trying to set a preference of type %s to value of type %s",
        GetTypeString(pref->GetType()), GetTypeString(impl_value->GetType()));
    return false;
  }

  // PrefService will make a DeepCopy of |impl_value|.
  pref_service->Set(name, *impl_value);
  return true;
}

void CefRequestContextImpl::ClearCertificateExceptions(
    CefRefPtr<CefCompletionCallback> callback) {
  GetBrowserContext(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::UI),
      base::Bind(&CefRequestContextImpl::ClearCertificateExceptionsInternal,
                 this, callback));
}

void CefRequestContextImpl::CloseAllConnections(
    CefRefPtr<CefCompletionCallback> callback) {
  GetRequestContextImpl(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
      base::Bind(&CefRequestContextImpl::CloseAllConnectionsInternal, this,
                 callback));
}

void CefRequestContextImpl::ResolveHost(
    const CefString& origin,
    CefRefPtr<CefResolveCallback> callback) {
  GetRequestContextImpl(
      BrowserThread::GetMessageLoopProxyForThread(BrowserThread::IO),
      base::Bind(&CefRequestContextImpl::ResolveHostInternal, this, origin,
                 callback));
}

cef_errorcode_t CefRequestContextImpl::ResolveHostCached(
    const CefString& origin,
    std::vector<CefString>& resolved_ips) {
  resolved_ips.clear();

  if (!CEF_CURRENTLY_ON_IOT()) {
    NOTREACHED() << "called on invalid thread";
    return ERR_FAILED;
  }

  if (!request_context_impl_)
    return ERR_FAILED;

  int retval = ERR_FAILED;

  net::HostResolver* host_resolver = request_context_impl_->GetHostResolver();
  if (host_resolver) {
    net::HostResolver::RequestInfo request_info(
        net::HostPortPair::FromURL(GURL(origin.ToString())));
    net::AddressList address_list;
    retval = host_resolver->ResolveFromCache(request_info, &address_list,
                                             net::BoundNetLog());
    if (retval == net::OK) {
      net::AddressList::const_iterator iter = address_list.begin();
      for (; iter != address_list.end(); ++iter)
        resolved_ips.push_back(iter->ToString());
    }
  }

  return static_cast<cef_errorcode_t>(retval);
}

CefRequestContextImpl::CefRequestContextImpl(
    scoped_refptr<CefBrowserContext> browser_context)
    : browser_context_(browser_context),
      settings_(browser_context->GetSettings()),
      handler_(browser_context->GetHandler()),
      unique_id_(0),
      request_context_impl_(NULL) {
}

CefRequestContextImpl::CefRequestContextImpl(
    const CefRequestContextSettings& settings,
    CefRefPtr<CefRequestContextHandler> handler)
    : settings_(settings),
      handler_(handler),
      unique_id_(g_next_id.GetNext()),
      request_context_impl_(NULL) {
}

CefRequestContextImpl::CefRequestContextImpl(
    CefRefPtr<CefRequestContextImpl> other,
    CefRefPtr<CefRequestContextHandler> handler)
    : other_(other),
      handler_(handler),
      unique_id_(g_next_id.GetNext()),
      request_context_impl_(NULL) {
}

void CefRequestContextImpl::EnsureBrowserContext() {
  GetBrowserContext();
  DCHECK(browser_context_.get());
  DCHECK(request_context_impl_);
}

void CefRequestContextImpl::GetBrowserContextOnUIThread(
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    const BrowserContextCallback& callback) {
  if (!CEF_CURRENTLY_ON_UIT()) {
    CEF_POST_TASK(CEF_UIT,
        base::Bind(&CefRequestContextImpl::GetBrowserContextOnUIThread,
                   this, task_runner, callback));
    return;
  }

  // Make sure the browser context exists.
  EnsureBrowserContext();

  if (task_runner->BelongsToCurrentThread()) {
    // Execute the callback immediately.
    callback.Run(browser_context_);
  } else {
    // Execute the callback on the target thread.
    task_runner->PostTask(FROM_HERE, base::Bind(callback, browser_context_));
  }
}

void CefRequestContextImpl::GetRequestContextImplOnIOThread(
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    const RequestContextCallback& callback,
    scoped_refptr<CefBrowserContext> browser_context) {
  if (!CEF_CURRENTLY_ON_IOT()) {
    CEF_POST_TASK(CEF_IOT,
        base::Bind(&CefRequestContextImpl::GetRequestContextImplOnIOThread,
                   this, task_runner, callback, browser_context));
    return;
  }

  DCHECK(request_context_impl_);

  // Make sure the request context exists.
  request_context_impl_->GetURLRequestContext();

  if (task_runner->BelongsToCurrentThread()) {
    // Execute the callback immediately.
    callback.Run(request_context_impl_);
  } else {
    // Execute the callback on the target thread.
    task_runner->PostTask(FROM_HERE,
        base::Bind(callback, make_scoped_refptr(request_context_impl_)));
  }
}

void CefRequestContextImpl::RegisterSchemeHandlerFactoryInternal(
    const CefString& scheme_name,
    const CefString& domain_name,
    CefRefPtr<CefSchemeHandlerFactory> factory,
    scoped_refptr<CefURLRequestContextGetterImpl> request_context) {
  CEF_REQUIRE_IOT();
  request_context->request_manager()->AddFactory(scheme_name, domain_name,
                                                 factory);
}

void CefRequestContextImpl::ClearSchemeHandlerFactoriesInternal(
    scoped_refptr<CefURLRequestContextGetterImpl> request_context) {
  CEF_REQUIRE_IOT();
  request_context->request_manager()->ClearFactories();
}

void CefRequestContextImpl::PurgePluginListCacheInternal(
    bool reload_pages,
    scoped_refptr<CefBrowserContext> browser_context) {
  CEF_REQUIRE_UIT();
  content::PluginService::GetInstance()->PurgePluginListCache(
      browser_context.get(), false);
}

void CefRequestContextImpl::ClearCertificateExceptionsInternal(
    CefRefPtr<CefCompletionCallback> callback,
    scoped_refptr<CefBrowserContext> browser_context) {
  CEF_REQUIRE_UIT();

  content::SSLHostStateDelegate* ssl_delegate =
      browser_context->GetSSLHostStateDelegate();
  if (ssl_delegate)
    ssl_delegate->Clear();

  if (callback) {
    CEF_POST_TASK(CEF_UIT,
        base::Bind(&CefCompletionCallback::OnComplete, callback.get()));
  }
}

void CefRequestContextImpl::CloseAllConnectionsInternal(
    CefRefPtr<CefCompletionCallback> callback,
    scoped_refptr<CefURLRequestContextGetterImpl> request_context) {
  CEF_REQUIRE_IOT();

  net::URLRequestContext* url_context = request_context->GetURLRequestContext();
  if (url_context) {
    net::HttpTransactionFactory* http_factory =
        url_context->http_transaction_factory();
    if (http_factory) {
      net::HttpCache* cache = http_factory->GetCache();
      if (cache)
        cache->CloseAllConnections();
    }
  }

  if (callback) {
    CEF_POST_TASK(CEF_UIT,
        base::Bind(&CefCompletionCallback::OnComplete, callback.get()));
  }
}

void CefRequestContextImpl::ResolveHostInternal(
    const CefString& origin,
    CefRefPtr<CefResolveCallback> callback,
    scoped_refptr<CefURLRequestContextGetterImpl> request_context) {
  CEF_REQUIRE_IOT();

  int retval = ERR_FAILED;

  // |helper| will be deleted in ResolveHostHelper::OnResolveCompleted().
  ResolveHostHelper* helper = new ResolveHostHelper(callback);

  net::HostResolver* host_resolver = request_context->GetHostResolver();
  if (host_resolver) {
    net::HostResolver::RequestInfo request_info(
        net::HostPortPair::FromURL(GURL(origin.ToString())));
    retval = host_resolver->Resolve(
        request_info, net::DEFAULT_PRIORITY,
        &helper->address_list_,
        base::Bind(&ResolveHostHelper::OnResolveCompleted,
                   base::Unretained(helper)),
        NULL, net::BoundNetLog());
    if (retval == net::ERR_IO_PENDING) {
      // The result will be delivered asynchronously via the callback.
      return;
    }
  }

  helper->OnResolveCompleted(retval);
}
