// Copyright (c) 2012 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/browser/devtools/render_view_devtools_agent_host.h"

#include "base/basictypes.h"
#include "base/lazy_instance.h"
#include "content/browser/child_process_security_policy_impl.h"
#include "content/browser/devtools/devtools_manager_impl.h"
#include "content/browser/devtools/devtools_protocol.h"
#include "content/browser/devtools/devtools_protocol_constants.h"
#include "content/browser/devtools/devtools_tracing_handler.h"
#include "content/browser/devtools/renderer_overrides_handler.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/browser/renderer_host/render_view_host_impl.h"
#include "content/browser/site_instance_impl.h"
#include "content/browser/web_contents/web_contents_impl.h"
#include "content/common/devtools_messages.h"
#include "content/public/browser/content_browser_client.h"
#include "content/public/browser/notification_service.h"
#include "content/public/browser/notification_types.h"

namespace content {

typedef std::vector<RenderViewDevToolsAgentHost*> Instances;

namespace {
base::LazyInstance<Instances>::Leaky g_instances = LAZY_INSTANCE_INITIALIZER;

static RenderViewDevToolsAgentHost* FindAgentHost(RenderViewHost* rvh) {
  if (g_instances == NULL)
    return NULL;
  for (Instances::iterator it = g_instances.Get().begin();
       it != g_instances.Get().end(); ++it) {
    if (rvh == (*it)->render_view_host())
      return *it;
  }
  return NULL;
}

}  // namespace

class RenderViewDevToolsAgentHost::DevToolsAgentHostRvhObserver
    : public RenderViewHostObserver {
 public:
  DevToolsAgentHostRvhObserver(RenderViewHost* rvh,
                               RenderViewDevToolsAgentHost* agent_host)
      : RenderViewHostObserver(rvh),
        agent_host_(agent_host) {
  }
  virtual ~DevToolsAgentHostRvhObserver() {}

  // RenderViewHostObserver overrides.
  virtual void RenderViewHostDestroyed(RenderViewHost* rvh) OVERRIDE {
    agent_host_->RenderViewHostDestroyed(rvh);
  }
  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE {
    return agent_host_->OnRvhMessageReceived(message);
  }
 private:
  RenderViewDevToolsAgentHost* agent_host_;
  DISALLOW_COPY_AND_ASSIGN(DevToolsAgentHostRvhObserver);
};

// static
scoped_refptr<DevToolsAgentHost>
DevToolsAgentHost::GetOrCreateFor(RenderViewHost* rvh) {
  RenderViewDevToolsAgentHost* result = FindAgentHost(rvh);
  if (!result)
    result = new RenderViewDevToolsAgentHost(rvh);
  return result;
}

// static
bool DevToolsAgentHost::HasFor(RenderViewHost* rvh) {
  return FindAgentHost(rvh) != NULL;
}

// static
bool DevToolsAgentHost::IsDebuggerAttached(WebContents* web_contents) {
  if (g_instances == NULL)
    return false;
  DevToolsManager* devtools_manager = DevToolsManager::GetInstance();
  if (!devtools_manager)
    return false;
  RenderViewHostDelegate* delegate =
      static_cast<WebContentsImpl*>(web_contents);
  for (Instances::iterator it = g_instances.Get().begin();
       it != g_instances.Get().end(); ++it) {
    RenderViewHost* rvh = (*it)->render_view_host_;
    if (rvh && rvh->GetDelegate() != delegate)
      continue;
    if ((*it)->IsAttached())
      return true;
  }
  return false;
}

//static
std::vector<RenderViewHost*> DevToolsAgentHost::GetValidRenderViewHosts() {
  std::vector<RenderViewHost*> result;
  RenderWidgetHost::List widgets = RenderWidgetHost::GetRenderWidgetHosts();
  for (size_t i = 0; i < widgets.size(); ++i) {
    // Ignore processes that don't have a connection, such as crashed contents.
    if (!widgets[i]->GetProcess()->HasConnection())
      continue;
    if (!widgets[i]->IsRenderView())
      continue;

    RenderViewHost* rvh = RenderViewHost::From(widgets[i]);
    WebContents* web_contents = WebContents::FromRenderViewHost(rvh);
    // Don't report a RenderViewHost if it is not the current RenderViewHost
    // for some WebContents.
    if (!web_contents || rvh != web_contents->GetRenderViewHost())
      continue;

    result.push_back(rvh);
  }
  return result;
}

// static
void RenderViewDevToolsAgentHost::OnCancelPendingNavigation(
    RenderViewHost* pending,
    RenderViewHost* current) {
  RenderViewDevToolsAgentHost* agent_host = FindAgentHost(pending);
  if (!agent_host)
    return;
  agent_host->DisconnectRenderViewHost();
  agent_host->ConnectRenderViewHost(current);
}

RenderViewDevToolsAgentHost::RenderViewDevToolsAgentHost(
    RenderViewHost* rvh)
    : overrides_handler_(new RendererOverridesHandler(this)),
      tracing_handler_(new DevToolsTracingHandler())
 {
  SetRenderViewHost(rvh);
  DevToolsProtocol::Notifier notifier(base::Bind(
      &RenderViewDevToolsAgentHost::OnDispatchOnInspectorFrontend,
      base::Unretained(this)));
  overrides_handler_->SetNotifier(notifier);
  tracing_handler_->SetNotifier(notifier);
  g_instances.Get().push_back(this);
  RenderViewHostDelegate* delegate = render_view_host_->GetDelegate();
  if (delegate && delegate->GetAsWebContents())
    Observe(delegate->GetAsWebContents());
  AddRef();  // Balanced in RenderViewHostDestroyed.
}

RenderViewHost* RenderViewDevToolsAgentHost::GetRenderViewHost() {
  return render_view_host_;
}

void RenderViewDevToolsAgentHost::DispatchOnInspectorBackend(
    const std::string& message) {
  std::string error_message;
  scoped_ptr<DevToolsProtocol::Command> command(
      DevToolsProtocol::ParseCommand(message, &error_message));
  if (command) {
    scoped_ptr<DevToolsProtocol::Response> overridden_response(
        overrides_handler_->HandleCommand(command.get()));
    if (!overridden_response)
      overridden_response = tracing_handler_->HandleCommand(command.get());
    if (overridden_response) {
      OnDispatchOnInspectorFrontend(overridden_response->Serialize());
      return;
    }
  }

  IPCDevToolsAgentHost::DispatchOnInspectorBackend(message);
}

void RenderViewDevToolsAgentHost::SendMessageToAgent(IPC::Message* msg) {
  if (!render_view_host_)
    return;
  msg->set_routing_id(render_view_host_->GetRoutingID());
  render_view_host_->Send(msg);
}

void RenderViewDevToolsAgentHost::OnClientAttached() {
  if (!render_view_host_)
    return;

  ChildProcessSecurityPolicyImpl::GetInstance()->GrantReadRawCookies(
      render_view_host_->GetProcess()->GetID());

  // TODO(kaznacheev): Move this call back to DevToolsManagerImpl when
  // ExtensionProcessManager no longer relies on this notification.
  DevToolsManagerImpl::GetInstance()->NotifyObservers(this, true);
}

void RenderViewDevToolsAgentHost::OnClientDetached() {
  if (!render_view_host_)
    return;

  bool process_has_agents = false;
  RenderProcessHost* render_process_host = render_view_host_->GetProcess();
  for (Instances::iterator it = g_instances.Get().begin();
       it != g_instances.Get().end(); ++it) {
    if (*it == this || !(*it)->IsAttached())
      continue;
    RenderViewHost* rvh = (*it)->render_view_host();
    if (rvh && rvh->GetProcess() == render_process_host)
      process_has_agents = true;
  }

  // We are the last to disconnect from the renderer -> revoke permissions.
  if (!process_has_agents) {
    ChildProcessSecurityPolicyImpl::GetInstance()->RevokeReadRawCookies(
        render_process_host->GetID());
  }

  // TODO(kaznacheev): Move this call back to DevToolsManagerImpl when
  // ExtensionProcessManager no longer relies on this notification.
  DevToolsManagerImpl::GetInstance()->NotifyObservers(this, false);
}

RenderViewDevToolsAgentHost::~RenderViewDevToolsAgentHost() {
  Instances::iterator it = std::find(g_instances.Get().begin(),
                                     g_instances.Get().end(),
                                     this);
  if (it != g_instances.Get().end())
    g_instances.Get().erase(it);
}

void RenderViewDevToolsAgentHost::AboutToNavigateRenderView(
    RenderViewHost* dest_rvh) {
  if (!render_view_host_)
    return;

  if (render_view_host_ == dest_rvh && static_cast<RenderViewHostImpl*>(
          render_view_host_)->render_view_termination_status() ==
              base::TERMINATION_STATUS_STILL_RUNNING)
    return;
  DisconnectRenderViewHost();
  ConnectRenderViewHost(dest_rvh);
}

void RenderViewDevToolsAgentHost::RenderProcessGone(
    base::TerminationStatus status) {
  switch(status) {
    case base::TERMINATION_STATUS_ABNORMAL_TERMINATION:
    case base::TERMINATION_STATUS_PROCESS_WAS_KILLED:
    case base::TERMINATION_STATUS_PROCESS_CRASHED:
      RenderViewCrashed();
      break;
    default:
      break;
  }
}

void RenderViewDevToolsAgentHost::DidAttachInterstitialPage() {
  if (!render_view_host_)
    return;
  // The rvh set in AboutToNavigateRenderView turned out to be interstitial.
  // Connect back to the real one.
  WebContents* web_contents =
    WebContents::FromRenderViewHost(render_view_host_);
  if (!web_contents)
    return;
  DisconnectRenderViewHost();
  ConnectRenderViewHost(web_contents->GetRenderViewHost());
}

void RenderViewDevToolsAgentHost::SetRenderViewHost(RenderViewHost* rvh) {
  render_view_host_ = rvh;
  rvh_observer_.reset(new DevToolsAgentHostRvhObserver(rvh, this));
}

void RenderViewDevToolsAgentHost::ConnectRenderViewHost(RenderViewHost* rvh) {
  SetRenderViewHost(rvh);
  Reattach(state_);
}

void RenderViewDevToolsAgentHost::DisconnectRenderViewHost() {
  OnClientDetached();
  rvh_observer_.reset();
  render_view_host_ = NULL;
}

void RenderViewDevToolsAgentHost::RenderViewHostDestroyed(
    RenderViewHost* rvh) {
  DCHECK(render_view_host_);
  scoped_refptr<RenderViewDevToolsAgentHost> protect(this);
  NotifyCloseListener();
  render_view_host_ = NULL;
  Release();
}

void RenderViewDevToolsAgentHost::RenderViewCrashed() {
  scoped_ptr<DevToolsProtocol::Notification> notification(
      DevToolsProtocol::CreateNotification(
          devtools::Inspector::targetCrashed::kName, NULL));
  DevToolsManagerImpl::GetInstance()->
      DispatchOnInspectorFrontend(this, notification->Serialize());
}

bool RenderViewDevToolsAgentHost::OnRvhMessageReceived(
    const IPC::Message& message) {
  bool handled = true;
  IPC_BEGIN_MESSAGE_MAP(RenderViewDevToolsAgentHost, message)
    IPC_MESSAGE_HANDLER(DevToolsClientMsg_DispatchOnInspectorFrontend,
                        OnDispatchOnInspectorFrontend)
    IPC_MESSAGE_HANDLER(DevToolsHostMsg_SaveAgentRuntimeState,
                        OnSaveAgentRuntimeState)
    IPC_MESSAGE_HANDLER(DevToolsHostMsg_ClearBrowserCache, OnClearBrowserCache)
    IPC_MESSAGE_HANDLER(DevToolsHostMsg_ClearBrowserCookies,
                        OnClearBrowserCookies)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP()
  return handled;
}

void RenderViewDevToolsAgentHost::OnSaveAgentRuntimeState(
    const std::string& state) {
  if (!render_view_host_)
    return;
  state_ = state;
}

void RenderViewDevToolsAgentHost::OnDispatchOnInspectorFrontend(
    const std::string& message) {
  if (!render_view_host_)
    return;
  DevToolsManagerImpl::GetInstance()->DispatchOnInspectorFrontend(
      this, message);
}

void RenderViewDevToolsAgentHost::OnClearBrowserCache() {
  if (render_view_host_)
    GetContentClient()->browser()->ClearCache(render_view_host_);
}

void RenderViewDevToolsAgentHost::OnClearBrowserCookies() {
  if (render_view_host_)
    GetContentClient()->browser()->ClearCookies(render_view_host_);
}

}  // namespace content