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 7 #ifndef nsXULTemplateQueryProcessorRDF_h__ 8 #define nsXULTemplateQueryProcessorRDF_h__ 9 10 #include "nsIRDFContainer.h" 11 #include "nsIRDFContainerUtils.h" 12 #include "nsIRDFDataSource.h" 13 #include "nsIRDFObserver.h" 14 #include "nsIRDFService.h" 15 #include "nsIXULTemplateBuilder.h" 16 #include "nsIXULTemplateQueryProcessor.h" 17 #include "nsCollationCID.h" 18 19 #include "nsResourceSet.h" 20 #include "nsRuleNetwork.h" 21 #include "nsRDFQuery.h" 22 #include "nsRDFBinding.h" 23 #include "nsXULTemplateResultSetRDF.h" 24 #include "nsCOMArray.h" 25 #include "nsString.h" 26 #include "nsClassHashtable.h" 27 #include "nsRefPtrHashtable.h" 28 #include "nsCycleCollectionParticipant.h" 29 #include "mozilla/Attributes.h" 30 31 #include "mozilla/Logging.h" 32 extern mozilla::LazyLogModule gXULTemplateLog; 33 34 class nsIContent; 35 class nsXULTemplateResultRDF; 36 37 /** 38 * An object that generates results from a query on an RDF graph 39 */ 40 class nsXULTemplateQueryProcessorRDF final : public nsIXULTemplateQueryProcessor, 41 public nsIRDFObserver 42 { 43 public: 44 typedef nsTArray<RefPtr<nsXULTemplateResultRDF> > ResultArray; 45 46 nsXULTemplateQueryProcessorRDF(); 47 48 nsresult InitGlobals(); 49 50 // nsISupports interface 51 NS_DECL_CYCLE_COLLECTING_ISUPPORTS 52 NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(nsXULTemplateQueryProcessorRDF, 53 nsIXULTemplateQueryProcessor) 54 55 // nsIXULTemplateQueryProcessor interface 56 NS_DECL_NSIXULTEMPLATEQUERYPROCESSOR 57 58 // nsIRDFObserver interface 59 NS_DECL_NSIRDFOBSERVER 60 61 /* 62 * Propagate all changes through the rule network when an assertion is 63 * added to the graph, adding any new results. 64 */ 65 nsresult 66 Propagate(nsIRDFResource* aSource, 67 nsIRDFResource* aProperty, 68 nsIRDFNode* aTarget); 69 70 /* 71 * Retract all changes through the rule network when an assertion is 72 * removed from the graph, removing any results that no longer match. 73 */ 74 nsresult 75 Retract(nsIRDFResource* aSource, 76 nsIRDFResource* aProperty, 77 nsIRDFNode* aTarget); 78 79 /* 80 * Synchronize results when the graph changes, updating their bindings. 81 */ 82 nsresult 83 SynchronizeAll(nsIRDFResource* aSource, 84 nsIRDFResource* aProperty, 85 nsIRDFNode* aOldTarget, 86 nsIRDFNode* aNewTarget); 87 88 /* 89 * Return true if a resource is a container 90 */ 91 nsresult 92 CheckContainer(nsIRDFResource* aTargetResource, 93 bool* aIsContainer); 94 95 /* 96 * Check if a resource does not have any children 97 */ 98 nsresult 99 CheckEmpty(nsIRDFResource* aTargetResource, 100 bool* aIsEmpty); 101 102 /** 103 * Check if a resource is a separator 104 */ 105 nsresult 106 CheckIsSeparator(nsIRDFResource* aResource, bool* aIsSeparator); 107 108 /* 109 * Compute the containment properties which are additional arcs which 110 * indicate that a node is a container, in additional to the RDF container 111 * tests. The computed list is stored in mContainmentProperties 112 */ 113 nsresult 114 ComputeContainmentProperties(nsIDOMNode* aRootNode); 115 116 /** 117 * Compile a query that uses the extended template syntax. The last 118 * compiled node of the query is returned as aLastNode. This node will 119 * have been added to mAllTests which owns the node. 120 */ 121 nsresult 122 CompileExtendedQuery(nsRDFQuery* aQuery, 123 nsIContent* aConditions, 124 TestNode** aLastNode); 125 126 /** 127 * Compile a single query child and return the compiled node in aResult. 128 * This node will have been added to mAllTests which owns the node and 129 * set as a child of aParentNode. 130 */ 131 virtual nsresult 132 CompileQueryChild(nsIAtom* aTag, 133 nsRDFQuery* aQuery, 134 nsIContent* aConditions, 135 TestNode* aParentNode, 136 TestNode** aResult); 137 138 /** 139 * Parse the value of a property test assertion for a condition or a simple 140 * rule based on the parseType attribute into the appropriate literal type. 141 */ 142 nsresult ParseLiteral(const nsString& aParseType, 143 const nsString& aValue, 144 nsIRDFNode** aResult); 145 146 /** 147 * Compile a <triple> condition and return the compiled node in aResult. 148 * This node will have been added to mAllTests which owns the node and 149 * set as a child of aParentNode. 150 */ 151 nsresult 152 CompileTripleCondition(nsRDFQuery* aQuery, 153 nsIContent* aCondition, 154 TestNode* aParentNode, 155 TestNode** aResult); 156 157 /** 158 * Compile a <member> condition and return the compiled node in aResult. 159 * This node will have been added to mAllTests which owns the node and 160 * set as a child of aParentNode. 161 */ 162 nsresult 163 CompileMemberCondition(nsRDFQuery* aQuery, 164 nsIContent* aCondition, 165 TestNode* aParentNode, 166 TestNode** aResult); 167 168 /** 169 * Add the default rules shared by all simple queries. This creates 170 * the content start node followed by a member test. The member TestNode 171 * is returned in aChildNode. Both nodes will have been added to mAllTests 172 * which owns the nodes. 173 */ 174 nsresult 175 AddDefaultSimpleRules(nsRDFQuery* aQuery, 176 TestNode** aChildNode); 177 178 /** 179 * Compile a query that's specified using the simple template 180 * syntax. Each TestNode is created in a chain, the last compiled node 181 * is returned as aLastNode. All nodes will have been added to mAllTests 182 * which owns the nodes. 183 */ 184 nsresult 185 CompileSimpleQuery(nsRDFQuery* aQuery, 186 nsIContent* aQueryElement, 187 TestNode** aLastNode); 188 189 RDFBindingSet* 190 GetBindingsForRule(nsIDOMNode* aRule); 191 192 /* 193 * Indicate that a result is dependant on a particular resource. When an 194 * assertion is added to or removed from the graph involving that 195 * resource, that result must be recalculated. 196 */ 197 void 198 AddBindingDependency(nsXULTemplateResultRDF* aResult, 199 nsIRDFResource* aResource); 200 201 /** 202 * Remove a dependency a result has on a particular resource. 203 */ 204 void 205 RemoveBindingDependency(nsXULTemplateResultRDF* aResult, 206 nsIRDFResource* aResource); 207 208 /** 209 * A memory element is a hash of an RDF triple. One exists for each triple 210 * that was involved in generating a result. This function adds this to a 211 * map, keyed by memory element, when the value is a list of results that 212 * depend on that memory element. When an RDF triple is removed from the 213 * datasource, RetractElement is called, and this map is examined to 214 * determine which results are no longer valid. 215 */ 216 nsresult 217 AddMemoryElements(const Instantiation& aInst, 218 nsXULTemplateResultRDF* aResult); 219 220 /** 221 * Remove the memory elements associated with a result when the result is 222 * no longer being used. 223 */ 224 nsresult 225 RemoveMemoryElements(const Instantiation& aInst, 226 nsXULTemplateResultRDF* aResult); 227 228 /** 229 * Remove the results associated with a memory element since the 230 * RDF triple the memory element is a hash of has been removed. 231 */ 232 void RetractElement(const MemoryElement& aMemoryElement); 233 234 /** 235 * Return the index of a result's resource in its RDF container 236 */ 237 int32_t 238 GetContainerIndexOf(nsIXULTemplateResult* aResult); 239 240 /** 241 * Given a result and a predicate to sort on, get the target value of 242 * the triple to use for sorting. The sort predicate is the predicate 243 * with '?sort=true' appended. 244 */ 245 nsresult 246 GetSortValue(nsIXULTemplateResult* aResult, 247 nsIRDFResource* aPredicate, 248 nsIRDFResource* aSortPredicate, 249 nsISupports** aResultNode); 250 GetDataSource()251 nsIRDFDataSource* GetDataSource() { return mDB; } 252 GetBuilder()253 nsIXULTemplateBuilder* GetBuilder() { return mBuilder; } 254 ContainmentProperties()255 nsResourceSet& ContainmentProperties() { return mContainmentProperties; } 256 257 nsresult 258 Log(const char* aOperation, 259 nsIRDFResource* aSource, 260 nsIRDFResource* aProperty, 261 nsIRDFNode* aTarget); 262 263 #define LOG(_op, _src, _prop, _targ) \ 264 Log(_op, _src, _prop, _targ) 265 266 protected: 267 ~nsXULTemplateQueryProcessorRDF(); 268 269 // We are an observer of the composite datasource. The cycle is 270 // broken when the document is destroyed. 271 nsCOMPtr<nsIRDFDataSource> mDB; 272 273 // weak reference to the builder, cleared when the document is destroyed 274 nsIXULTemplateBuilder* mBuilder; 275 276 // true if the query processor has been initialized 277 bool mQueryProcessorRDFInited; 278 279 // true if results have been generated. Once set, bindings can no longer 280 // be added. If they were, the binding value arrays for results that have 281 // already been generated would be the wrong size 282 bool mGenerationStarted; 283 284 // nesting level for RDF batch notifications 285 int32_t mUpdateBatchNest; 286 287 // containment properties that are checked to determine if a resource is 288 // a container 289 nsResourceSet mContainmentProperties; 290 291 // the end node of the default simple node hierarchy 292 TestNode* mSimpleRuleMemberTest; 293 294 // the reference variable 295 nsCOMPtr<nsIAtom> mRefVariable; 296 297 // the last ref that was calculated, used for simple rules 298 nsCOMPtr<nsIXULTemplateResult> mLastRef; 299 300 /** 301 * A map between nsIRDFNodes that form the left-hand side (the subject) of 302 * a <binding> and an array of nsIXULTemplateResults. When a new assertion 303 * is added to the graph involving a particular rdf node, it is looked up 304 * in this binding map. If it exists, the corresponding results must then 305 * be synchronized. 306 */ 307 nsClassHashtable<nsISupportsHashKey, ResultArray> mBindingDependencies; 308 309 /** 310 * A map between memory elements and an array of nsIXULTemplateResults. 311 * When a triple is unasserted from the graph, the corresponding results 312 * no longer match so they must be removed. 313 */ 314 nsClassHashtable<nsUint32HashKey, 315 nsCOMArray<nsXULTemplateResultRDF> > mMemoryElementToResultMap; 316 317 // map of the rules to the bindings for those rules. 318 // XXXndeakin this might be better just as an array since there is usually 319 // ten or fewer rules 320 nsRefPtrHashtable<nsISupportsHashKey, RDFBindingSet> mRuleToBindingsMap; 321 322 /** 323 * The queries 324 */ 325 nsTArray<nsCOMPtr<nsITemplateRDFQuery> > mQueries; 326 327 /** 328 * All of the RDF tests in the rule network, which are checked when a new 329 * assertion is added to the graph. This is a subset of mAllTests, which 330 * also includes non-RDF tests. 331 */ 332 ReteNodeSet mRDFTests; 333 334 /** 335 * All of the tests in the rule network, owned by this list 336 */ 337 ReteNodeSet mAllTests; 338 339 // pseudo-constants 340 static nsrefcnt gRefCnt; 341 342 public: 343 static nsIRDFService* gRDFService; 344 static nsIRDFContainerUtils* gRDFContainerUtils; 345 static nsIRDFResource* kNC_BookmarkSeparator; 346 static nsIRDFResource* kRDF_type; 347 }; 348 349 #endif // nsXULTemplateQueryProcessorRDF_h__ 350