// 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/renderer_host/render_widget_helper.h"

#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/lazy_instance.h"
#include "base/posix/eintr_wrapper.h"
#include "base/threading/thread.h"
#include "base/threading/thread_restrictions.h"
#include "content/browser/dom_storage/session_storage_namespace_impl.h"
#include "content/browser/loader/resource_dispatcher_host_impl.h"
#include "content/browser/renderer_host/render_process_host_impl.h"
#include "content/browser/renderer_host/render_view_host_impl.h"
#include "content/common/view_messages.h"

namespace content {
namespace {

typedef std::map<int, RenderWidgetHelper*> WidgetHelperMap;
base::LazyInstance<WidgetHelperMap> g_widget_helpers =
    LAZY_INSTANCE_INITIALIZER;

void AddWidgetHelper(int render_process_id,
                     const scoped_refptr<RenderWidgetHelper>& widget_helper) {
  DCHECK_CURRENTLY_ON(BrowserThread::IO);
  // We don't care if RenderWidgetHelpers overwrite an existing process_id. Just
  // want this to be up to date.
  g_widget_helpers.Get()[render_process_id] = widget_helper.get();
}

}  // namespace

RenderWidgetHelper::RenderWidgetHelper()
    : render_process_id_(-1),
      resource_dispatcher_host_(NULL) {
}

RenderWidgetHelper::~RenderWidgetHelper() {
  DCHECK_CURRENTLY_ON(BrowserThread::IO);

  // Delete this RWH from the map if it is found.
  WidgetHelperMap& widget_map = g_widget_helpers.Get();
  WidgetHelperMap::iterator it = widget_map.find(render_process_id_);
  if (it != widget_map.end() && it->second == this)
    widget_map.erase(it);
}

void RenderWidgetHelper::Init(
    int render_process_id,
    ResourceDispatcherHostImpl* resource_dispatcher_host) {
  render_process_id_ = render_process_id;
  resource_dispatcher_host_ = resource_dispatcher_host;

  BrowserThread::PostTask(
      BrowserThread::IO, FROM_HERE,
      base::Bind(&AddWidgetHelper,
                 render_process_id_, make_scoped_refptr(this)));
}

int RenderWidgetHelper::GetNextRoutingID() {
  return next_routing_id_.GetNext() + 1;
}

// static
RenderWidgetHelper* RenderWidgetHelper::FromProcessHostID(
    int render_process_host_id) {
  DCHECK_CURRENTLY_ON(BrowserThread::IO);
  WidgetHelperMap::const_iterator ci = g_widget_helpers.Get().find(
      render_process_host_id);
  return (ci == g_widget_helpers.Get().end())? NULL : ci->second;
}

void RenderWidgetHelper::ResumeDeferredNavigation(
    const GlobalRequestID& request_id) {
  BrowserThread::PostTask(
      BrowserThread::IO, FROM_HERE,
      base::Bind(&RenderWidgetHelper::OnResumeDeferredNavigation,
                 this,
                 request_id));
}

void RenderWidgetHelper::ResumeRequestsForView(int route_id) {
  // We only need to resume blocked requests if we used a valid route_id.
  // See CreateNewWindow.
  if (route_id != MSG_ROUTING_NONE) {
    BrowserThread::PostTask(
        BrowserThread::IO, FROM_HERE,
        base::Bind(&RenderWidgetHelper::OnResumeRequestsForView,
            this, route_id));
  }
}

void RenderWidgetHelper::OnResumeDeferredNavigation(
    const GlobalRequestID& request_id) {
  resource_dispatcher_host_->ResumeDeferredNavigation(request_id);
}

void RenderWidgetHelper::CreateNewWindow(
    const ViewHostMsg_CreateWindow_Params& params,
    bool no_javascript_access,
    base::ProcessHandle render_process,
    int32_t* route_id,
    int32_t* main_frame_route_id,
    int32_t* main_frame_widget_route_id,
    SessionStorageNamespace* session_storage_namespace) {
  if (params.opener_suppressed || no_javascript_access) {
    // If the opener is supppressed or script access is disallowed, we should
    // open the window in a new BrowsingInstance, and thus a new process. That
    // means the current renderer process will not be able to route messages to
    // it. Because of this, we will immediately show and navigate the window
    // in OnCreateWindowOnUI, using the params provided here.
    *route_id = MSG_ROUTING_NONE;
    *main_frame_route_id = MSG_ROUTING_NONE;
    *main_frame_widget_route_id = MSG_ROUTING_NONE;
  } else {
    *route_id = GetNextRoutingID();
    *main_frame_route_id = GetNextRoutingID();
    // TODO(avi): When RenderViewHostImpl has-a RenderWidgetHostImpl, this
    // should be updated to give the widget a distinct routing ID.
    // https://crbug.com/545684
    *main_frame_widget_route_id = *route_id;
    // Block resource requests until the view is created, since the HWND might
    // be needed if a response ends up creating a plugin.
    resource_dispatcher_host_->BlockRequestsForRoute(
        render_process_id_, *route_id);
  }

  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&RenderWidgetHelper::OnCreateWindowOnUI, this, params,
                 *route_id, *main_frame_route_id, *main_frame_widget_route_id,
                 make_scoped_refptr(session_storage_namespace)));
}

void RenderWidgetHelper::OnCreateWindowOnUI(
    const ViewHostMsg_CreateWindow_Params& params,
    int32_t route_id,
    int32_t main_frame_route_id,
    int32_t main_frame_widget_route_id,
    SessionStorageNamespace* session_storage_namespace) {
  RenderViewHostImpl* host =
      RenderViewHostImpl::FromID(render_process_id_, params.opener_id);
  if (host)
    host->CreateNewWindow(route_id, main_frame_route_id,
                          main_frame_widget_route_id, params,
                          session_storage_namespace);
}

void RenderWidgetHelper::OnResumeRequestsForView(int route_id) {
  resource_dispatcher_host_->ResumeBlockedRequestsForRoute(
      render_process_id_, route_id);
}

void RenderWidgetHelper::CreateNewWidget(int opener_id,
                                         blink::WebPopupType popup_type,
                                         int* route_id) {
  *route_id = GetNextRoutingID();
  BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
                          base::Bind(&RenderWidgetHelper::OnCreateWidgetOnUI,
                                     this, opener_id, *route_id, popup_type));
}

void RenderWidgetHelper::CreateNewFullscreenWidget(int opener_id,
                                                   int* route_id) {
  *route_id = GetNextRoutingID();
  BrowserThread::PostTask(
      BrowserThread::UI, FROM_HERE,
      base::Bind(&RenderWidgetHelper::OnCreateFullscreenWidgetOnUI, this,
                 opener_id, *route_id));
}

void RenderWidgetHelper::OnCreateWidgetOnUI(int32_t opener_id,
                                            int32_t route_id,
                                            blink::WebPopupType popup_type) {
  RenderViewHostImpl* host = RenderViewHostImpl::FromID(
      render_process_id_, opener_id);
  if (host)
    host->CreateNewWidget(route_id, popup_type);
}

void RenderWidgetHelper::OnCreateFullscreenWidgetOnUI(int32_t opener_id,
                                                      int32_t route_id) {
  RenderViewHostImpl* host = RenderViewHostImpl::FromID(
      render_process_id_, opener_id);
  if (host)
    host->CreateNewFullscreenWidget(route_id);
}

}  // namespace content