diff -r 000000000000 -r 6474c204b198 content/xul/templates/src/nsXULTemplateBuilder.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/xul/templates/src/nsXULTemplateBuilder.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,503 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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/. */
+
+#ifndef nsXULTemplateBuilder_h__
+#define nsXULTemplateBuilder_h__
+
+#include "nsStubDocumentObserver.h"
+#include "nsIScriptSecurityManager.h"
+#include "nsIObserver.h"
+#include "nsIRDFCompositeDataSource.h"
+#include "nsIRDFContainer.h"
+#include "nsIRDFContainerUtils.h"
+#include "nsIRDFDataSource.h"
+#include "nsIRDFObserver.h"
+#include "nsIRDFService.h"
+#include "nsIXULTemplateBuilder.h"
+
+#include "nsCOMArray.h"
+#include "nsTArray.h"
+#include "nsDataHashtable.h"
+#include "nsTemplateRule.h"
+#include "nsTemplateMatch.h"
+#include "nsIXULTemplateQueryProcessor.h"
+#include "nsCycleCollectionParticipant.h"
+
+#include "prlog.h"
+#ifdef PR_LOGGING
+extern PRLogModuleInfo* gXULTemplateLog;
+#endif
+
+class nsIContent;
+class nsIObserverService;
+class nsIRDFCompositeDataSource;
+class nsIXULDocument;
+
+/**
+ * An object that translates an RDF graph into a presentation using a
+ * set of rules.
+ */
+class nsXULTemplateBuilder : public nsIXULTemplateBuilder,
+                             public nsIObserver,
+                             public nsStubDocumentObserver
+{
+    void CleanUp(bool aIsFinal);
+
+public:
+    nsXULTemplateBuilder();
+    virtual ~nsXULTemplateBuilder();
+
+    nsresult InitGlobals();
+
+    /**
+     * Clear the template builder structures. The aIsFinal flag is set to true
+     * when the template is going away.
+     */
+    virtual void Uninit(bool aIsFinal);
+
+    // nsISupports interface
+    NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+    NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsXULTemplateBuilder,
+                                             nsIXULTemplateBuilder)
+
+    // nsIXULTemplateBuilder interface
+    NS_DECL_NSIXULTEMPLATEBUILDER
+
+    // nsIObserver Interface
+    NS_DECL_NSIOBSERVER
+
+    // nsIMutationObserver
+    NS_DECL_NSIMUTATIONOBSERVER_ATTRIBUTECHANGED
+    NS_DECL_NSIMUTATIONOBSERVER_CONTENTREMOVED
+    NS_DECL_NSIMUTATIONOBSERVER_NODEWILLBEDESTROYED
+
+    /**
+     * Remove an old result and/or add a new result. This method will retrieve
+     * the set of containers where the result could be inserted and either add
+     * the new result to those containers, or remove the result from those
+     * containers. UpdateResultInContainer is called for each container.
+     *
+     * @param aOldResult result to remove
+     * @param aNewResult result to add
+     * @param aQueryNode query node for new result
+     */
+    nsresult
+    UpdateResult(nsIXULTemplateResult* aOldResult,
+                 nsIXULTemplateResult* aNewResult,
+                 nsIDOMNode* aQueryNode);
+
+    /**
+     * Remove an old result and/or add a new result from a specific container.
+     *
+     * @param aOldResult result to remove
+     * @param aNewResult result to add
+     * @param aQueryNode queryset for the new result
+     * @param aOldId id of old result
+     * @param aNewId id of new result
+     * @param aInsertionPoint container to remove or add result inside
+     */
+    nsresult
+    UpdateResultInContainer(nsIXULTemplateResult* aOldResult,
+                            nsIXULTemplateResult* aNewResult,
+                            nsTemplateQuerySet* aQuerySet,
+                            nsIRDFResource* aOldId,
+                            nsIRDFResource* aNewId,
+                            nsIContent* aInsertionPoint);
+
+    nsresult
+    ComputeContainmentProperties();
+
+    static bool
+    IsTemplateElement(nsIContent* aContent);
+
+    virtual nsresult
+    RebuildAll() = 0; // must be implemented by subclasses
+
+    void RunnableRebuild() { Rebuild(); }
+    void RunnableLoadAndRebuild() {
+      Uninit(false);  // Reset results
+
+      nsCOMPtr<nsIDocument> doc = mRoot ? mRoot->GetDocument() : nullptr;
+      if (doc) {
+        bool shouldDelay;
+        LoadDataSources(doc, &shouldDelay);
+        if (!shouldDelay) {
+          Rebuild();
+        }
+      }
+    }
+
+    // mRoot should not be cleared until after Uninit is finished so that
+    // generated content can be removed during uninitialization.
+    void UninitFalse() { Uninit(false); mRoot = nullptr; }
+    void UninitTrue() { Uninit(true); mRoot = nullptr; }
+
+    /**
+     * Find the <template> tag that applies for this builder
+     */
+    nsresult
+    GetTemplateRoot(nsIContent** aResult);
+
+    /**
+     * Compile the template's queries
+     */
+    nsresult
+    CompileQueries();
+
+    /**
+     * Compile the template given a <template> in aTemplate. This function
+     * is called recursively to handle queries inside a queryset. For the
+     * outer pass, aIsQuerySet will be false, while the inner pass this will
+     * be true.
+     *
+     * aCanUseTemplate will be set to true if the template's queries could be
+     * compiled, and false otherwise. If false, the entire template is
+     * invalid.
+     *
+     * @param aTemplate <template> to compile
+     * @param aQuerySet first queryset
+     * @param aIsQuerySet true if 
+     * @param aPriority the queryset index, incremented when a new one is added
+     * @param aCanUseTemplate true if template is valid
+     */
+    nsresult
+    CompileTemplate(nsIContent* aTemplate,
+                    nsTemplateQuerySet* aQuerySet,
+                    bool aIsQuerySet,
+                    int32_t* aPriority,
+                    bool* aCanUseTemplate);
+
+    /**
+     * Compile a query using the extended syntax. For backwards compatible RDF
+     * syntax where there is no <query>, the <conditions> becomes the query.
+     *
+     * @param aRuleElement <rule> element
+     * @param aActionElement <action> element
+     * @param aMemberVariable member variable for the query
+     * @param aQuerySet the queryset
+     */
+    nsresult 
+    CompileExtendedQuery(nsIContent* aRuleElement,
+                         nsIContent* aActionElement,
+                         nsIAtom* aMemberVariable,
+                         nsTemplateQuerySet* aQuerySet);
+
+    /**
+     * Determine the ref variable and tag from inside a RDF query.
+     */
+    void DetermineRDFQueryRef(nsIContent* aQueryElement, nsIAtom** tag);
+
+    /**
+     * Determine the member variable from inside an action body. It will be
+     * the value of the uri attribute on a node.
+     */
+    already_AddRefed<nsIAtom> DetermineMemberVariable(nsIContent* aElement);
+
+    /**
+     * Compile a simple query. A simple query is one that doesn't have a
+     * <query> and should use a default query which would normally just return
+     * a list of children of the reference point.
+     *
+     * @param aRuleElement the <rule>
+     * @param aQuerySet the query set
+     * @param aCanUseTemplate true if the query is valid
+     */
+    nsresult 
+    CompileSimpleQuery(nsIContent* aRuleElement,
+                       nsTemplateQuerySet* aQuerySet,
+                       bool* aCanUseTemplate);
+
+    /**
+     * Compile the <conditions> tag in a rule
+     *
+     * @param aRule template rule
+     * @param aConditions <conditions> element
+     */
+    nsresult
+    CompileConditions(nsTemplateRule* aRule, nsIContent* aConditions);
+
+    /**
+     * Compile a <where> tag in a condition. The caller should set
+     * *aCurrentCondition to null for the first condition. This value will be
+     * updated to point to the new condition before returning. The conditions
+     * will be added to the rule aRule by this method.
+     *
+     * @param aRule template rule
+     * @param aCondition <where> element
+     * @param aCurrentCondition compiled condition
+     */
+    nsresult
+    CompileWhereCondition(nsTemplateRule* aRule,
+                          nsIContent* aCondition,
+                          nsTemplateCondition** aCurrentCondition);
+
+    /**
+     * Compile the <bindings> for an extended template syntax rule.
+     */
+    nsresult
+    CompileBindings(nsTemplateRule* aRule, nsIContent* aBindings);
+
+    /**
+     * Compile a single binding for an extended template syntax rule.
+     */
+    nsresult
+    CompileBinding(nsTemplateRule* aRule, nsIContent* aBinding);
+
+    /**
+     * Add automatic bindings for simple rules
+     */
+    nsresult
+    AddSimpleRuleBindings(nsTemplateRule* aRule, nsIContent* aElement);
+
+    static void
+    AddBindingsFor(nsXULTemplateBuilder* aSelf,
+                   const nsAString& aVariable,
+                   void* aClosure);
+
+    /**
+     * Load the datasources for the template. shouldDelayBuilding is an out
+     * parameter which will be set to true to indicate that content building
+     * should not be performed yet as the datasource has not yet loaded. If
+     * false, the datasource has already loaded so building can proceed
+     * immediately. In the former case, the datasource or query processor
+     * should either rebuild the template or update results when the
+     * datasource is loaded as needed.
+     */
+    nsresult
+    LoadDataSources(nsIDocument* aDoc, bool* shouldDelayBuilding);
+
+    /**
+     * Called by LoadDataSources to load a datasource given a uri list
+     * in aDataSource. The list is a set of uris separated by spaces.
+     * If aIsRDFQuery is true, then this is for an RDF datasource which
+     * causes the method to check for additional flags specific to the
+     * RDF processor.
+     */
+    nsresult
+    LoadDataSourceUrls(nsIDocument* aDocument,
+                       const nsAString& aDataSources,
+                       bool aIsRDFQuery,
+                       bool* aShouldDelayBuilding);
+
+    nsresult
+    InitHTMLTemplateRoot();
+
+    /**
+     * Determine which rule matches a given result. aContainer is used for
+     * tag matching and is optional for non-content generating builders.
+     * The returned matched rule is always one of the rules owned by the
+     * query set aQuerySet.
+     *
+     * @param aContainer parent where generated content will be inserted
+     * @param aResult result to match
+     * @param aQuerySet query set to examine the rules of
+     * @param aMatchedRule [out] rule that has matched, or null if any.
+     * @param aRuleIndex [out] index of the rule
+     */
+    nsresult
+    DetermineMatchedRule(nsIContent* aContainer,
+                         nsIXULTemplateResult* aResult,
+                         nsTemplateQuerySet* aQuerySet,
+                         nsTemplateRule** aMatchedRule,
+                         int16_t *aRuleIndex);
+
+    // XXX sigh, the string template foo doesn't mix with
+    // operator->*() on egcs-1.1.2, so we'll need to explicitly pass
+    // "this" and use good ol' fashioned static callbacks.
+    void
+    ParseAttribute(const nsAString& aAttributeValue,
+                   void (*aVariableCallback)(nsXULTemplateBuilder* aThis, const nsAString&, void*),
+                   void (*aTextCallback)(nsXULTemplateBuilder* aThis, const nsAString&, void*),
+                   void* aClosure);
+
+    nsresult
+    SubstituteText(nsIXULTemplateResult* aMatch,
+                   const nsAString& aAttributeValue,
+                   nsAString& aResult);
+
+    static void
+    SubstituteTextAppendText(nsXULTemplateBuilder* aThis, const nsAString& aText, void* aClosure);
+
+    static void
+    SubstituteTextReplaceVariable(nsXULTemplateBuilder* aThis, const nsAString& aVariable, void* aClosure);    
+
+    nsresult 
+    IsSystemPrincipal(nsIPrincipal *principal, bool *result);
+
+    /**
+     * Convenience method which gets a resource for a result. If a result
+     * doesn't have a resource set, it will create one from the result's id.
+     */
+    nsresult GetResultResource(nsIXULTemplateResult* aResult,
+                               nsIRDFResource** aResource);
+
+protected:
+    nsCOMPtr<nsISupports> mDataSource;
+    nsCOMPtr<nsIRDFDataSource> mDB;
+    nsCOMPtr<nsIRDFCompositeDataSource> mCompDB;
+
+    /**
+     * Circular reference, broken when the document is destroyed.
+     */
+    nsCOMPtr<nsIContent> mRoot;
+
+    /**
+     * The root result, translated from the root element's ref
+     */
+    nsCOMPtr<nsIXULTemplateResult> mRootResult;
+
+    nsCOMArray<nsIXULBuilderListener> mListeners;
+
+    /**
+     * The query processor which generates results
+     */
+    nsCOMPtr<nsIXULTemplateQueryProcessor> mQueryProcessor;
+
+    /**
+     * The list of querysets
+     */
+    nsTArray<nsTemplateQuerySet *> mQuerySets;
+
+    /**
+     * Set to true if the rules have already been compiled
+     */
+    bool          mQueriesCompiled;
+
+    /**
+     * The default reference and member variables.
+     */
+    nsCOMPtr<nsIAtom> mRefVariable;
+    nsCOMPtr<nsIAtom> mMemberVariable;
+
+    /**
+     * The match map contains nsTemplateMatch objects, one for each unique
+     * match found, keyed by the resource for that match. A particular match
+     * will contain a linked list of all of the matches for that unique result
+     * id. Only one is active at a time. When a match is retracted, look in
+     * the match map, remove it, and apply the next valid match in sequence to
+     * make active.
+     */
+    nsDataHashtable<nsISupportsHashKey, nsTemplateMatch*> mMatchMap;
+
+    // pseudo-constants
+    static nsrefcnt gRefCnt;
+    static nsIRDFService*            gRDFService;
+    static nsIRDFContainerUtils*     gRDFContainerUtils;
+    static nsIScriptSecurityManager* gScriptSecurityManager;
+    static nsIPrincipal*             gSystemPrincipal;
+    static nsIObserverService*       gObserverService;
+
+    enum {
+        eDontTestEmpty = (1 << 0),
+        eDontRecurse = (1 << 1),
+        eLoggingEnabled = (1 << 2)
+    };
+
+    int32_t mFlags;
+
+    /**
+     * Stack-based helper class to maintain a list of ``activated''
+     * resources; i.e., resources for which we are currently building
+     * content.
+     */
+    class ActivationEntry {
+    public:
+        nsIRDFResource   *mResource;
+        ActivationEntry  *mPrevious;
+        ActivationEntry **mLink;
+
+        ActivationEntry(nsIRDFResource *aResource, ActivationEntry **aLink)
+            : mResource(aResource),
+              mPrevious(*aLink),
+              mLink(aLink) { *mLink = this; }
+
+        ~ActivationEntry() { *mLink = mPrevious; }
+    };
+
+    /**
+     * The top of the stack of resources that we're currently building
+     * content for.
+     */
+    ActivationEntry *mTop;
+
+    /**
+     * Determine if a resource is currently on the activation stack.
+     */
+    bool
+    IsActivated(nsIRDFResource *aResource);
+
+    /**
+     * Returns true if content may be generated for a result, or false if it
+     * cannot, for example, if it would be created inside a closed container.
+     * Those results will be generated when the container is opened.
+     * If false is returned, no content should be generated. Possible 
+     * insertion locations may optionally be set for new content, depending on
+     * the builder being used. Note that *aLocations or some items within
+     * aLocations may be null.
+     */
+    virtual bool
+    GetInsertionLocations(nsIXULTemplateResult* aResult,
+                          nsCOMArray<nsIContent>** aLocations) = 0;
+
+    /**
+     * Must be implemented by subclasses. Handle removing the generated
+     * output for aOldMatch and adding new output for aNewMatch. Either
+     * aOldMatch or aNewMatch may be null. aContext is the location returned
+     * from the call to MayGenerateResult.
+     */
+    virtual nsresult
+    ReplaceMatch(nsIXULTemplateResult* aOldResult,
+                 nsTemplateMatch* aNewMatch,
+                 nsTemplateRule* aNewMatchRule,
+                 void *aContext) = 0;
+
+    /**
+     * Must be implemented by subclasses. Handle change in bound
+     * variable values for aResult. aModifiedVars contains the set
+     * of variables that have changed.
+     * @param aResult the ersult for which variable bindings has changed.
+     * @param aModifiedVars the set of variables for which the bindings
+     * have changed.
+     */
+    virtual nsresult
+    SynchronizeResult(nsIXULTemplateResult* aResult) = 0;
+
+    /**
+     * Output a new match or removed match to the console.
+     *
+     * @param aId id of the result
+     * @param aMatch new or removed match
+     * @param aIsNew true for new matched, false for removed matches
+     */
+    void
+    OutputMatchToLog(nsIRDFResource* aId,
+                     nsTemplateMatch* aMatch,
+                     bool aIsNew);
+
+    virtual void Traverse(nsCycleCollectionTraversalCallback &cb) const
+    {
+    }
+
+    /**
+     * Start observing events from the observer service and the given
+     * document.
+     *
+     * @param aDocument the document to observe
+     */
+    void StartObserving(nsIDocument* aDocument);
+
+    /**
+     * Stop observing events from the observer service and any associated
+     * document.
+     */
+    void StopObserving();
+
+    /**
+     * Document that we're observing. Weak ref!
+     */
+    nsIDocument* mObservedDocument;
+};
+
+#endif // nsXULTemplateBuilder_h__