dom/xml/nsXMLPrettyPrinter.cpp

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsXMLPrettyPrinter.h"
   7 #include "nsContentUtils.h"
   8 #include "nsIDOMCSSStyleDeclaration.h"
   9 #include "nsIDOMDocumentXBL.h"
  10 #include "nsIObserver.h"
  11 #include "nsIXSLTProcessor.h"
  12 #include "nsSyncLoadService.h"
  13 #include "nsPIDOMWindow.h"
  14 #include "nsIDOMElement.h"
  15 #include "nsIDOMDocument.h"
  16 #include "nsIServiceManager.h"
  17 #include "nsNetUtil.h"
  18 #include "mozilla/dom/Element.h"
  19 #include "nsIDOMDocumentFragment.h"
  20 #include "nsBindingManager.h"
  21 #include "nsXBLService.h"
  22 #include "nsIScriptSecurityManager.h"
  23 #include "mozilla/Preferences.h"
  24 #include "nsIDocument.h"
  25 #include "nsVariant.h"
  26 #include "nsIDOMCustomEvent.h"
  27
  28 using namespace mozilla;
  29 using namespace mozilla::dom;
  30
  31 NS_IMPL_ISUPPORTS(nsXMLPrettyPrinter,
  32                   nsIDocumentObserver,
  33                   nsIMutationObserver)
  34
  35 nsXMLPrettyPrinter::nsXMLPrettyPrinter() : mDocument(nullptr),
  36                                            mUnhookPending(false)
  37 {
  38 }
  39
  40 nsXMLPrettyPrinter::~nsXMLPrettyPrinter()
  41 {
  42     NS_ASSERTION(!mDocument, "we shouldn't be referencing the document still");
  43 }
  44
  45 nsresult
  46 nsXMLPrettyPrinter::PrettyPrint(nsIDocument* aDocument,
  47                                 bool* aDidPrettyPrint)
  48 {
  49     *aDidPrettyPrint = false;
  50
  51     // Check for iframe with display:none. Such iframes don't have presshells
  52     if (!aDocument->GetShell()) {
  53         return NS_OK;
  54     }
  55
  56     // check if we're in an invisible iframe
  57     nsPIDOMWindow *internalWin = aDocument->GetWindow();
  58     nsCOMPtr<nsIDOMElement> frameElem;
  59     if (internalWin) {
  60         internalWin->GetFrameElement(getter_AddRefs(frameElem));
  61     }
  62
  63     if (frameElem) {
  64         nsCOMPtr<nsIDOMCSSStyleDeclaration> computedStyle;
  65         nsCOMPtr<nsIDOMDocument> frameOwnerDoc;
  66         frameElem->GetOwnerDocument(getter_AddRefs(frameOwnerDoc));
  67         if (frameOwnerDoc) {
  68             nsCOMPtr<nsIDOMWindow> window;
  69             frameOwnerDoc->GetDefaultView(getter_AddRefs(window));
  70             if (window) {
  71                 window->GetComputedStyle(frameElem,
  72                                          EmptyString(),
  73                                          getter_AddRefs(computedStyle));
  74             }
  75         }
  76
  77         if (computedStyle) {
  78             nsAutoString visibility;
  79             computedStyle->GetPropertyValue(NS_LITERAL_STRING("visibility"),
  80                                             visibility);
  81             if (!visibility.EqualsLiteral("visible")) {
  82
  83                 return NS_OK;
  84             }
  85         }
  86     }
  87
  88     // check the pref
  89     if (!Preferences::GetBool("layout.xml.prettyprint", true)) {
  90         return NS_OK;
  91     }
  92
  93     // Ok, we should prettyprint. Let's do it!
  94     *aDidPrettyPrint = true;
  95     nsresult rv = NS_OK;
  96
  97     // Load the XSLT
  98     nsCOMPtr<nsIURI> xslUri;
  99     rv = NS_NewURI(getter_AddRefs(xslUri),
 100                    NS_LITERAL_CSTRING("chrome://global/content/xml/XMLPrettyPrint.xsl"));
 101     NS_ENSURE_SUCCESS(rv, rv);
 102
 103     nsCOMPtr<nsIDOMDocument> xslDocument;
 104     rv = nsSyncLoadService::LoadDocument(xslUri, nullptr, nullptr, true,
 105                                          getter_AddRefs(xslDocument));
 106     NS_ENSURE_SUCCESS(rv, rv);
 107
 108     // Transform the document
 109     nsCOMPtr<nsIXSLTProcessor> transformer =
 110         do_CreateInstance("@mozilla.org/document-transformer;1?type=xslt", &rv);
 111     NS_ENSURE_SUCCESS(rv, rv);
 112
 113     rv = transformer->ImportStylesheet(xslDocument);
 114     NS_ENSURE_SUCCESS(rv, rv);
 115
 116     nsCOMPtr<nsIDOMDocumentFragment> resultFragment;
 117     nsCOMPtr<nsIDOMDocument> sourceDocument = do_QueryInterface(aDocument);
 118     rv = transformer->TransformToFragment(sourceDocument, sourceDocument,
 119                                           getter_AddRefs(resultFragment));
 120     NS_ENSURE_SUCCESS(rv, rv);
 121
 122     //
 123     // Apply the prettprint XBL binding.
 124     //
 125     // We take some shortcuts here. In particular, we don't bother invoking the
 126     // contstructor (since the binding has no constructor), and we don't bother
 127     // calling LoadBindingDocument because it's a chrome:// URI and thus will get
 128     // sync loaded no matter what.
 129     //
 130
 131     // Grab the XBL service.
 132     nsXBLService* xblService = nsXBLService::GetInstance();
 133     NS_ENSURE_TRUE(xblService, NS_ERROR_NOT_AVAILABLE);
 134
 135     // Compute the binding URI.
 136     nsCOMPtr<nsIURI> bindingUri;
 137     rv = NS_NewURI(getter_AddRefs(bindingUri),
 138         NS_LITERAL_STRING("chrome://global/content/xml/XMLPrettyPrint.xml#prettyprint"));
 139     NS_ENSURE_SUCCESS(rv, rv);
 140
 141     // Compute the bound element.
 142     nsCOMPtr<nsIContent> rootCont = aDocument->GetRootElement();
 143     NS_ENSURE_TRUE(rootCont, NS_ERROR_UNEXPECTED);
 144
 145     // Grab the system principal.
 146     nsCOMPtr<nsIPrincipal> sysPrincipal;
 147     nsContentUtils::GetSecurityManager()->
 148         GetSystemPrincipal(getter_AddRefs(sysPrincipal));
 149
 150     // Load the bindings.
 151     nsRefPtr<nsXBLBinding> unused;
 152     bool ignored;
 153     rv = xblService->LoadBindings(rootCont, bindingUri, sysPrincipal,
 154                                   getter_AddRefs(unused), &ignored);
 155     NS_ENSURE_SUCCESS(rv, rv);
 156
 157     // Fire an event at the bound element to pass it |resultFragment|.
 158     nsCOMPtr<nsIDOMEvent> domEvent;
 159     rv = NS_NewDOMCustomEvent(getter_AddRefs(domEvent), rootCont,
 160                               nullptr, nullptr);
 161     NS_ENSURE_SUCCESS(rv, rv);
 162     nsCOMPtr<nsIDOMCustomEvent> customEvent = do_QueryInterface(domEvent);
 163     MOZ_ASSERT(customEvent);
 164     nsCOMPtr<nsIWritableVariant> resultFragmentVariant = new nsVariant();
 165     rv = resultFragmentVariant->SetAsISupports(resultFragment);
 166     MOZ_ASSERT(NS_SUCCEEDED(rv));
 167     rv = customEvent->InitCustomEvent(NS_LITERAL_STRING("prettyprint-dom-created"),
 168                                       /* bubbles = */ false, /* cancelable = */ false,
 169                                       /* detail = */ resultFragmentVariant);
 170     NS_ENSURE_SUCCESS(rv, rv);
 171     customEvent->SetTrusted(true);
 172     bool dummy;
 173     rv = rootCont->DispatchEvent(domEvent, &dummy);
 174     NS_ENSURE_SUCCESS(rv, rv);
 175
 176     // Observe the document so we know when to switch to "normal" view
 177     aDocument->AddObserver(this);
 178     mDocument = aDocument;
 179
 180     NS_ADDREF_THIS();
 181
 182     return NS_OK;
 183 }
 184
 185 void
 186 nsXMLPrettyPrinter::MaybeUnhook(nsIContent* aContent)
 187 {
 188     // If there either aContent is null (the document-node was modified) or
 189     // there isn't a binding parent we know it's non-anonymous content.
 190     if ((!aContent || !aContent->GetBindingParent()) && !mUnhookPending) {
 191         // Can't blindly to mUnhookPending after AddScriptRunner,
 192         // since AddScriptRunner _could_ in theory run us
 193         // synchronously
 194         mUnhookPending = true;
 195         nsContentUtils::AddScriptRunner(
 196           NS_NewRunnableMethod(this, &nsXMLPrettyPrinter::Unhook));
 197     }
 198 }
 199
 200 void
 201 nsXMLPrettyPrinter::Unhook()
 202 {
 203     mDocument->RemoveObserver(this);
 204     nsCOMPtr<Element> element = mDocument->GetDocumentElement();
 205
 206     if (element) {
 207         mDocument->BindingManager()->ClearBinding(element);
 208     }
 209
 210     mDocument = nullptr;
 211
 212     NS_RELEASE_THIS();
 213 }
 214
 215 void
 216 nsXMLPrettyPrinter::AttributeChanged(nsIDocument* aDocument,
 217                                      Element* aElement,
 218                                      int32_t aNameSpaceID,
 219                                      nsIAtom* aAttribute,
 220                                      int32_t aModType)
 221 {
 222     MaybeUnhook(aElement);
 223 }
 224
 225 void
 226 nsXMLPrettyPrinter::ContentAppended(nsIDocument* aDocument,
 227                                     nsIContent* aContainer,
 228                                     nsIContent* aFirstNewContent,
 229                                     int32_t aNewIndexInContainer)
 230 {
 231     MaybeUnhook(aContainer);
 232 }
 233
 234 void
 235 nsXMLPrettyPrinter::ContentInserted(nsIDocument* aDocument,
 236                                     nsIContent* aContainer,
 237                                     nsIContent* aChild,
 238                                     int32_t aIndexInContainer)
 239 {
 240     MaybeUnhook(aContainer);
 241 }
 242
 243 void
 244 nsXMLPrettyPrinter::ContentRemoved(nsIDocument* aDocument,
 245                                    nsIContent* aContainer,
 246                                    nsIContent* aChild,
 247                                    int32_t aIndexInContainer,
 248                                    nsIContent* aPreviousSibling)
 249 {
 250     MaybeUnhook(aContainer);
 251 }
 252
 253 void
 254 nsXMLPrettyPrinter::NodeWillBeDestroyed(const nsINode* aNode)
 255 {
 256     mDocument = nullptr;
 257     NS_RELEASE_THIS();
 258 }
 259
 260
 261 nsresult NS_NewXMLPrettyPrinter(nsXMLPrettyPrinter** aPrinter)
 262 {
 263     *aPrinter = new nsXMLPrettyPrinter;
 264     NS_ADDREF(*aPrinter);
 265     return NS_OK;
 266 }