/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsContextMenuInfo.h"

#include "nsIImageLoadingContent.h"
#include "imgLoader.h"
#include "nsIDOMDocument.h"
#include "nsIDOMHTMLDocument.h"
#include "nsIDOMHTMLElement.h"
#include "nsIDOMHTMLHtmlElement.h"
#include "nsIDOMHTMLAnchorElement.h"
#include "nsIDOMHTMLImageElement.h"
#include "nsIDOMHTMLAreaElement.h"
#include "nsIDOMHTMLLinkElement.h"
#include "nsIDOMWindow.h"
#include "nsICSSDeclaration.h"
#include "nsIDOMCSSValue.h"
#include "nsIDOMCSSPrimitiveValue.h"
#include "nsNetUtil.h"
#include "nsUnicharUtils.h"
#include "nsIDocument.h"
#include "nsIPrincipal.h"
#include "nsIContentSecurityPolicy.h"
#include "nsIContentPolicy.h"
#include "nsAutoPtr.h"
#include "imgRequestProxy.h"

using mozilla::dom::Element;
using mozilla::ErrorResult;

NS_IMPL_ISUPPORTS(nsContextMenuInfo, nsIContextMenuInfo)

nsContextMenuInfo::nsContextMenuInfo()
{
}

nsContextMenuInfo::~nsContextMenuInfo()
{
}

NS_IMETHODIMP
nsContextMenuInfo::GetMouseEvent(nsIDOMEvent** aEvent)
{
  NS_ENSURE_ARG_POINTER(aEvent);
  NS_IF_ADDREF(*aEvent = mMouseEvent);
  return NS_OK;
}

NS_IMETHODIMP
nsContextMenuInfo::GetTargetNode(nsIDOMNode** aNode)
{
  NS_ENSURE_ARG_POINTER(aNode);
  NS_IF_ADDREF(*aNode = mDOMNode);
  return NS_OK;
}

NS_IMETHODIMP
nsContextMenuInfo::GetAssociatedLink(nsAString& aHRef)
{
  NS_ENSURE_STATE(mAssociatedLink);
  aHRef.Truncate(0);

  nsCOMPtr<nsIDOMElement> content(do_QueryInterface(mAssociatedLink));
  nsAutoString localName;
  if (content) {
    content->GetLocalName(localName);
  }

  nsCOMPtr<nsIDOMElement> linkContent;
  ToLowerCase(localName);
  if (localName.EqualsLiteral("a") ||
      localName.EqualsLiteral("area") ||
      localName.EqualsLiteral("link")) {
    bool hasAttr;
    content->HasAttribute(NS_LITERAL_STRING("href"), &hasAttr);
    if (hasAttr) {
      linkContent = content;
      nsCOMPtr<nsIDOMHTMLAnchorElement> anchor(do_QueryInterface(linkContent));
      if (anchor) {
        anchor->GetHref(aHRef);
      } else {
        nsCOMPtr<nsIDOMHTMLAreaElement> area(do_QueryInterface(linkContent));
        if (area) {
          area->GetHref(aHRef);
        } else {
          nsCOMPtr<nsIDOMHTMLLinkElement> link(do_QueryInterface(linkContent));
          if (link) {
            link->GetHref(aHRef);
          }
        }
      }
    }
  } else {
    nsCOMPtr<nsIDOMNode> curr;
    mAssociatedLink->GetParentNode(getter_AddRefs(curr));
    while (curr) {
      content = do_QueryInterface(curr);
      if (!content) {
        break;
      }
      content->GetLocalName(localName);
      ToLowerCase(localName);
      if (localName.EqualsLiteral("a")) {
        bool hasAttr;
        content->HasAttribute(NS_LITERAL_STRING("href"), &hasAttr);
        if (hasAttr) {
          linkContent = content;
          nsCOMPtr<nsIDOMHTMLAnchorElement> anchor(
            do_QueryInterface(linkContent));
          if (anchor) {
            anchor->GetHref(aHRef);
          }
        } else {
          linkContent = nullptr; // Links can't be nested.
        }
        break;
      }

      nsCOMPtr<nsIDOMNode> temp = curr;
      temp->GetParentNode(getter_AddRefs(curr));
    }
  }

  return NS_OK;
}

NS_IMETHODIMP
nsContextMenuInfo::GetImageContainer(imgIContainer** aImageContainer)
{
  NS_ENSURE_ARG_POINTER(aImageContainer);
  NS_ENSURE_STATE(mDOMNode);

  nsCOMPtr<imgIRequest> request;
  GetImageRequest(mDOMNode, getter_AddRefs(request));
  if (request) {
    return request->GetImage(aImageContainer);
  }

  return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsContextMenuInfo::GetImageSrc(nsIURI** aURI)
{
  NS_ENSURE_ARG_POINTER(aURI);
  NS_ENSURE_STATE(mDOMNode);

  nsCOMPtr<nsIImageLoadingContent> content(do_QueryInterface(mDOMNode));
  NS_ENSURE_TRUE(content, NS_ERROR_FAILURE);
  return content->GetCurrentURI(aURI);
}

NS_IMETHODIMP
nsContextMenuInfo::GetBackgroundImageContainer(imgIContainer** aImageContainer)
{
  NS_ENSURE_ARG_POINTER(aImageContainer);
  NS_ENSURE_STATE(mDOMNode);

  RefPtr<imgRequestProxy> request;
  GetBackgroundImageRequest(mDOMNode, getter_AddRefs(request));
  if (request) {
    return request->GetImage(aImageContainer);
  }

  return NS_ERROR_FAILURE;
}

NS_IMETHODIMP
nsContextMenuInfo::GetBackgroundImageSrc(nsIURI** aURI)
{
  NS_ENSURE_ARG_POINTER(aURI);
  NS_ENSURE_STATE(mDOMNode);

  RefPtr<imgRequestProxy> request;
  GetBackgroundImageRequest(mDOMNode, getter_AddRefs(request));
  if (request) {
    return request->GetURI(aURI);
  }

  return NS_ERROR_FAILURE;
}

nsresult
nsContextMenuInfo::GetImageRequest(nsIDOMNode* aDOMNode, imgIRequest** aRequest)
{
  NS_ENSURE_ARG(aDOMNode);
  NS_ENSURE_ARG_POINTER(aRequest);

  // Get content
  nsCOMPtr<nsIImageLoadingContent> content(do_QueryInterface(aDOMNode));
  NS_ENSURE_TRUE(content, NS_ERROR_FAILURE);

  return content->GetRequest(nsIImageLoadingContent::CURRENT_REQUEST, aRequest);
}

bool
nsContextMenuInfo::HasBackgroundImage(nsIDOMNode* aDOMNode)
{
  NS_ENSURE_TRUE(aDOMNode, false);

  RefPtr<imgRequestProxy> request;
  GetBackgroundImageRequest(aDOMNode, getter_AddRefs(request));

  return (request != nullptr);
}

nsresult
nsContextMenuInfo::GetBackgroundImageRequest(nsIDOMNode* aDOMNode,
                                             imgRequestProxy** aRequest)
{

  NS_ENSURE_ARG(aDOMNode);
  NS_ENSURE_ARG_POINTER(aRequest);

  nsCOMPtr<nsIDOMNode> domNode = aDOMNode;

  // special case for the <html> element: if it has no background-image
  // we'll defer to <body>
  nsCOMPtr<nsIDOMHTMLHtmlElement> htmlElement = do_QueryInterface(domNode);
  if (htmlElement) {
    nsCOMPtr<nsIDOMHTMLElement> element = do_QueryInterface(domNode);
    nsAutoString nameSpace;
    element->GetNamespaceURI(nameSpace);
    if (nameSpace.IsEmpty()) {
      nsresult rv = GetBackgroundImageRequestInternal(domNode, aRequest);
      if (NS_SUCCEEDED(rv) && *aRequest) {
        return NS_OK;
      }

      // no background-image found
      nsCOMPtr<nsIDOMDocument> document;
      domNode->GetOwnerDocument(getter_AddRefs(document));
      nsCOMPtr<nsIDOMHTMLDocument> htmlDocument(do_QueryInterface(document));
      NS_ENSURE_TRUE(htmlDocument, NS_ERROR_FAILURE);

      nsCOMPtr<nsIDOMHTMLElement> body;
      htmlDocument->GetBody(getter_AddRefs(body));
      domNode = do_QueryInterface(body);
      NS_ENSURE_TRUE(domNode, NS_ERROR_FAILURE);
    }
  }
  return GetBackgroundImageRequestInternal(domNode, aRequest);
}

nsresult
nsContextMenuInfo::GetBackgroundImageRequestInternal(nsIDOMNode* aDOMNode,
                                                     imgRequestProxy** aRequest)
{
  NS_ENSURE_ARG_POINTER(aDOMNode);

  nsCOMPtr<nsIDOMNode> domNode = aDOMNode;
  nsCOMPtr<nsIDOMNode> parentNode;

  nsCOMPtr<nsIDOMDocument> document;
  domNode->GetOwnerDocument(getter_AddRefs(document));
  NS_ENSURE_TRUE(document, NS_ERROR_FAILURE);

  nsCOMPtr<nsIDOMWindow> window;
  document->GetDefaultView(getter_AddRefs(window));
  NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);

  nsCOMPtr<nsPIDOMWindow> piWindow = do_QueryInterface(window);
  MOZ_ASSERT(piWindow);
  piWindow = piWindow->GetCurrentInnerWindow();
  MOZ_ASSERT(piWindow);

  nsCOMPtr<nsIDOMCSSPrimitiveValue> primitiveValue;
  nsAutoString bgStringValue;

  nsCOMPtr<nsIDocument> doc(do_QueryInterface(document));
  nsCOMPtr<nsIPrincipal> principal = doc ? doc->NodePrincipal() : nullptr;

  while (true) {
    nsCOMPtr<Element> domElement(do_QueryInterface(domNode));
    // bail for the parent node of the root element or null argument
    if (!domElement) {
      break;
    }

    ErrorResult dummy;
    nsCOMPtr<nsICSSDeclaration> computedStyle =
      piWindow->GetComputedStyle(*domElement, EmptyString(), dummy);
    dummy.SuppressException();
    if (computedStyle) {
      nsCOMPtr<nsIDOMCSSValue> cssValue;
      computedStyle->GetPropertyCSSValue(NS_LITERAL_STRING("background-image"),
                                         getter_AddRefs(cssValue));
      primitiveValue = do_QueryInterface(cssValue);
      if (primitiveValue) {
        primitiveValue->GetStringValue(bgStringValue);
        if (!bgStringValue.EqualsLiteral("none")) {
          nsCOMPtr<nsIURI> bgUri;
          NS_NewURI(getter_AddRefs(bgUri), bgStringValue);
          NS_ENSURE_TRUE(bgUri, NS_ERROR_FAILURE);

          RefPtr<imgLoader> il = imgLoader::GetInstance();
          NS_ENSURE_TRUE(il, NS_ERROR_FAILURE);

          return il->LoadImage(bgUri, nullptr, nullptr,
                               doc->GetReferrerPolicy(), principal, nullptr,
                               nullptr, nullptr, nsIRequest::LOAD_NORMAL,
                               nullptr, nsIContentPolicy::TYPE_INTERNAL_IMAGE,
                               EmptyString(), aRequest);
        }
      }

      // bail if we encounter non-transparent background-color
      computedStyle->GetPropertyCSSValue(NS_LITERAL_STRING("background-color"),
                                         getter_AddRefs(cssValue));
      primitiveValue = do_QueryInterface(cssValue);
      if (primitiveValue) {
        primitiveValue->GetStringValue(bgStringValue);
        if (!bgStringValue.EqualsLiteral("transparent")) {
          return NS_ERROR_FAILURE;
        }
      }
    }

    domNode->GetParentNode(getter_AddRefs(parentNode));
    domNode = parentNode;
  }

  return NS_ERROR_FAILURE;
}