// Copyright 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 "extensions/renderer/extension_helper.h"

#include "content/public/renderer/render_view.h"
#include "content/public/renderer/render_view_visitor.h"
#include "extensions/common/constants.h"
#include "extensions/common/extension_messages.h"
#include "extensions/common/permissions/permissions_data.h"
#include "extensions/common/url_pattern_set.h"
#include "extensions/renderer/api/automation/automation_api_helper.h"
#include "extensions/renderer/console.h"
#include "extensions/renderer/dispatcher.h"
#include "third_party/WebKit/public/platform/WebURLRequest.h"
#include "third_party/WebKit/public/web/WebConsoleMessage.h"
#include "third_party/WebKit/public/web/WebDocument.h"
#include "third_party/WebKit/public/web/WebLocalFrame.h"
#include "third_party/WebKit/public/web/WebView.h"

using content::ConsoleMessageLevel;
using blink::WebConsoleMessage;
using blink::WebDataSource;
using blink::WebFrame;
using blink::WebLocalFrame;
using blink::WebURLRequest;
using blink::WebView;

namespace extensions {

namespace {

// A RenderViewVisitor class that iterates through the set of available
// views, looking for a view of the given type, in the given browser window
// and within the given extension.
// Used to accumulate the list of views associated with an extension.
class ViewAccumulator : public content::RenderViewVisitor {
 public:
  ViewAccumulator(const std::string& extension_id,
                  int browser_window_id,
                  ViewType view_type)
      : extension_id_(extension_id),
        browser_window_id_(browser_window_id),
        view_type_(view_type) {
  }

  std::vector<content::RenderView*> views() { return views_; }

  // Returns false to terminate the iteration.
  bool Visit(content::RenderView* render_view) override {
    ExtensionHelper* helper = ExtensionHelper::Get(render_view);
    if (!ViewTypeMatches(helper->view_type(), view_type_))
      return true;

    GURL url = render_view->GetWebView()->mainFrame()->document().url();
    if (!url.SchemeIs(kExtensionScheme))
      return true;
    const std::string& extension_id = url.host();
    if (extension_id != extension_id_)
      return true;

    if (browser_window_id_ != extension_misc::kUnknownWindowId &&
        helper->browser_window_id() != browser_window_id_) {
      return true;
    }

    views_.push_back(render_view);

    if (view_type_ == VIEW_TYPE_EXTENSION_BACKGROUND_PAGE)
      return false;  // There can be only one...
    return true;
  }

 private:
  // Returns true if |type| "isa" |match|.
  static bool ViewTypeMatches(ViewType type, ViewType match) {
    if (type == match)
      return true;

    // INVALID means match all.
    if (match == VIEW_TYPE_INVALID)
      return true;

    return false;
  }

  std::string extension_id_;
  int browser_window_id_;
  ViewType view_type_;
  std::vector<content::RenderView*> views_;
};

}  // namespace

// static
std::vector<content::RenderView*> ExtensionHelper::GetExtensionViews(
    const std::string& extension_id,
    int browser_window_id,
    ViewType view_type) {
  ViewAccumulator accumulator(extension_id, browser_window_id, view_type);
  content::RenderView::ForEach(&accumulator);
  return accumulator.views();
}

// static
content::RenderView* ExtensionHelper::GetBackgroundPage(
    const std::string& extension_id) {
  ViewAccumulator accumulator(extension_id, extension_misc::kUnknownWindowId,
                              VIEW_TYPE_EXTENSION_BACKGROUND_PAGE);
  content::RenderView::ForEach(&accumulator);
  CHECK_LE(accumulator.views().size(), 1u);
  if (accumulator.views().size() == 0)
    return NULL;
  return accumulator.views()[0];
}

ExtensionHelper::ExtensionHelper(content::RenderView* render_view,
                                 Dispatcher* dispatcher)
    : content::RenderViewObserver(render_view),
      content::RenderViewObserverTracker<ExtensionHelper>(render_view),
      dispatcher_(dispatcher),
      view_type_(VIEW_TYPE_INVALID),
      tab_id_(-1),
      browser_window_id_(-1) {
  // Lifecycle managed by RenderViewObserver.
  new AutomationApiHelper(render_view);
}

ExtensionHelper::~ExtensionHelper() {
}

bool ExtensionHelper::OnMessageReceived(const IPC::Message& message) {
  bool handled = true;
  IPC_BEGIN_MESSAGE_MAP(ExtensionHelper, message)
    IPC_MESSAGE_HANDLER(ExtensionMsg_Response, OnExtensionResponse)
    IPC_MESSAGE_HANDLER(ExtensionMsg_MessageInvoke, OnExtensionMessageInvoke)
    IPC_MESSAGE_HANDLER(ExtensionMsg_SetFrameName, OnSetFrameName)
    IPC_MESSAGE_HANDLER(ExtensionMsg_SetTabId, OnSetTabId)
    IPC_MESSAGE_HANDLER(ExtensionMsg_UpdateBrowserWindowId,
                        OnUpdateBrowserWindowId)
    IPC_MESSAGE_HANDLER(ExtensionMsg_NotifyRenderViewType,
                        OnNotifyRendererViewType)
    IPC_MESSAGE_HANDLER(ExtensionMsg_AddMessageToConsole,
                        OnAddMessageToConsole)
    IPC_MESSAGE_HANDLER(ExtensionMsg_AppWindowClosed,
                        OnAppWindowClosed)
    IPC_MESSAGE_HANDLER(ExtensionMsg_UpdateTabSpecificPermissions,
                        OnUpdateTabSpecificPermissions)
    IPC_MESSAGE_HANDLER(ExtensionMsg_ClearTabSpecificPermissions,
                        OnClearTabSpecificPermissions)
    IPC_MESSAGE_UNHANDLED(handled = false)
  IPC_END_MESSAGE_MAP()
  return handled;
}

void ExtensionHelper::DidCreateDocumentElement(WebLocalFrame* frame) {
  dispatcher_->DidCreateDocumentElement(frame);
}

void ExtensionHelper::DraggableRegionsChanged(blink::WebFrame* frame) {
  blink::WebVector<blink::WebDraggableRegion> webregions =
      frame->document().draggableRegions();
  std::vector<DraggableRegion> regions;
  for (size_t i = 0; i < webregions.size(); ++i) {
    DraggableRegion region;
    region.bounds = webregions[i].bounds;
    region.draggable = webregions[i].draggable;
    regions.push_back(region);
  }
  Send(new ExtensionHostMsg_UpdateDraggableRegions(routing_id(), regions));
}

void ExtensionHelper::DidMatchCSS(
    blink::WebLocalFrame* frame,
    const blink::WebVector<blink::WebString>& newly_matching_selectors,
    const blink::WebVector<blink::WebString>& stopped_matching_selectors) {
  dispatcher_->DidMatchCSS(
      frame, newly_matching_selectors, stopped_matching_selectors);
}

void ExtensionHelper::OnExtensionResponse(int request_id,
                                          bool success,
                                          const base::ListValue& response,
                                          const std::string& error) {
  dispatcher_->OnExtensionResponse(request_id,
                                   success,
                                   response,
                                   error);
}

void ExtensionHelper::OnExtensionMessageInvoke(const std::string& extension_id,
                                               const std::string& module_name,
                                               const std::string& function_name,
                                               const base::ListValue& args,
                                               bool user_gesture) {
  dispatcher_->InvokeModuleSystemMethod(
      render_view(), extension_id, module_name, function_name, args,
      user_gesture);
}

void ExtensionHelper::OnNotifyRendererViewType(ViewType type) {
  view_type_ = type;
}

void ExtensionHelper::OnSetFrameName(const std::string& name) {
  blink::WebView* web_view = render_view()->GetWebView();
  if (web_view)
    web_view->mainFrame()->setName(blink::WebString::fromUTF8(name));
}

void ExtensionHelper::OnSetTabId(int init_tab_id) {
  CHECK_EQ(tab_id_, -1);
  CHECK_GE(init_tab_id, 0);
  tab_id_ = init_tab_id;
}

void ExtensionHelper::OnUpdateBrowserWindowId(int window_id) {
  browser_window_id_ = window_id;
}

void ExtensionHelper::OnAddMessageToConsole(ConsoleMessageLevel level,
                                            const std::string& message) {
  console::AddMessage(render_view(), level, message);
}

void ExtensionHelper::OnAppWindowClosed() {
  v8::HandleScope scope(v8::Isolate::GetCurrent());
  v8::Handle<v8::Context> v8_context =
      render_view()->GetWebView()->mainFrame()->mainWorldScriptContext();
  ScriptContext* script_context =
      dispatcher_->script_context_set().GetByV8Context(v8_context);
  if (!script_context)
    return;
  script_context->module_system()->CallModuleMethod("app.window",
                                                    "onAppWindowClosed");
}

void ExtensionHelper::OnUpdateTabSpecificPermissions(
    const GURL& url,
    const std::string& extension_id,
    const extensions::URLPatternSet& origin_set) {
  // Check against the URL to avoid races.
  GURL active_url(render_view()->GetWebView()->mainFrame()->document().url());
  if (active_url != url)
    return;

  const Extension* extension = dispatcher_->extensions()->GetByID(extension_id);
  if (!extension)
    return;

  extension->permissions_data()->UpdateTabSpecificPermissions(
      tab_id_,
      new extensions::PermissionSet(extensions::APIPermissionSet(),
                                    extensions::ManifestPermissionSet(),
                                    origin_set,
                                    extensions::URLPatternSet()));
}

void ExtensionHelper::OnClearTabSpecificPermissions(
    const std::vector<std::string>& extension_ids) {
  for (const auto& id : extension_ids) {
    const extensions::Extension* extension =
        dispatcher_->extensions()->GetByID(id);
    if (extension)
      extension->permissions_data()->ClearTabSpecificPermissions(tab_id_);
  }
}

}  // namespace extensions