michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef TRANSFRMX_EXPR_H
michael@0: #define TRANSFRMX_EXPR_H
michael@0: 
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "nsAutoPtr.h"
michael@0: #include "txExprResult.h"
michael@0: #include "txCore.h"
michael@0: #include "nsString.h"
michael@0: #include "txOwningArray.h"
michael@0: #include "nsIAtom.h"
michael@0: 
michael@0: #ifdef DEBUG
michael@0: #define TX_TO_STRING
michael@0: #endif
michael@0: 
michael@0: /*
michael@0:   XPath class definitions.
michael@0:   Much of this code was ported from XSL:P.
michael@0: */
michael@0: 
michael@0: class nsIAtom;
michael@0: class txIParseContext;
michael@0: class txIMatchContext;
michael@0: class txIEvalContext;
michael@0: class txNodeSet;
michael@0: class txXPathNode;
michael@0: 
michael@0: /**
michael@0:  * A Base Class for all XSL Expressions
michael@0: **/
michael@0: class Expr
michael@0: {
michael@0: public:
michael@0:     Expr()
michael@0:     {
michael@0:         MOZ_COUNT_CTOR(Expr);
michael@0:     }
michael@0:     virtual ~Expr()
michael@0:     {
michael@0:         MOZ_COUNT_DTOR(Expr);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Evaluates this Expr based on the given context node and processor state
michael@0:      * @param context the context node for evaluation of this Expr
michael@0:      * @param ps the ContextState containing the stack information needed
michael@0:      * for evaluation
michael@0:      * @return the result of the evaluation
michael@0:     **/
michael@0:     virtual nsresult evaluate(txIEvalContext* aContext,
michael@0:                               txAExprResult** aResult) = 0;
michael@0: 
michael@0: 
michael@0:     /**
michael@0:      * Returns the type of this expression.
michael@0:      */
michael@0:     enum ExprType {
michael@0:         LOCATIONSTEP_EXPR,
michael@0:         PATH_EXPR,
michael@0:         UNION_EXPR,
michael@0:         LITERAL_EXPR,
michael@0:         OTHER_EXPR
michael@0:     };
michael@0:     virtual ExprType getType()
michael@0:     {
michael@0:       return OTHER_EXPR;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns the type or types of results this Expr return.
michael@0:      */
michael@0:     typedef uint16_t ResultType;
michael@0:     enum {
michael@0:         NODESET_RESULT = 0x01,
michael@0:         BOOLEAN_RESULT = 0x02,
michael@0:         NUMBER_RESULT = 0x04,
michael@0:         STRING_RESULT = 0x08,
michael@0:         RTF_RESULT = 0x10,
michael@0:         ANY_RESULT = 0xFFFF
michael@0:     };
michael@0:     virtual ResultType getReturnType() = 0;
michael@0:     bool canReturnType(ResultType aType)
michael@0:     {
michael@0:         return (getReturnType() & aType) != 0;
michael@0:     }
michael@0: 
michael@0:     typedef uint16_t ContextSensitivity;
michael@0:     enum {
michael@0:         NO_CONTEXT = 0x00,
michael@0:         NODE_CONTEXT = 0x01,
michael@0:         POSITION_CONTEXT = 0x02,
michael@0:         SIZE_CONTEXT = 0x04,
michael@0:         NODESET_CONTEXT = POSITION_CONTEXT | SIZE_CONTEXT,
michael@0:         VARIABLES_CONTEXT = 0x08,
michael@0:         PRIVATE_CONTEXT = 0x10,
michael@0:         ANY_CONTEXT = 0xFFFF
michael@0:     };
michael@0: 
michael@0:     /**
michael@0:      * Returns true if this expression is sensitive to *any* of
michael@0:      * the requested contexts in aContexts.
michael@0:      */
michael@0:     virtual bool isSensitiveTo(ContextSensitivity aContexts) = 0;
michael@0: 
michael@0:     /**
michael@0:      * Returns sub-expression at given position
michael@0:      */
michael@0:     virtual Expr* getSubExprAt(uint32_t aPos) = 0;
michael@0: 
michael@0:     /**
michael@0:      * Replace sub-expression at given position. Does not delete the old
michael@0:      * expression, that is the responsibility of the caller.
michael@0:      */
michael@0:     virtual void setSubExprAt(uint32_t aPos, Expr* aExpr) = 0;
michael@0: 
michael@0:     virtual nsresult evaluateToBool(txIEvalContext* aContext,
michael@0:                                     bool& aResult);
michael@0: 
michael@0:     virtual nsresult evaluateToString(txIEvalContext* aContext,
michael@0:                                       nsString& aResult);
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0:     /**
michael@0:      * Returns the String representation of this Expr.
michael@0:      * @param dest the String to use when creating the String
michael@0:      * representation. The String representation will be appended to
michael@0:      * any data in the destination String, to allow cascading calls to
michael@0:      * other #toString() methods for Expressions.
michael@0:      * @return the String representation of this Expr.
michael@0:     **/
michael@0:     virtual void toString(nsAString& str) = 0;
michael@0: #endif
michael@0: }; //-- Expr
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0: #define TX_DECL_TOSTRING \
michael@0:     void toString(nsAString& aDest);
michael@0: #define TX_DECL_GETNAMEATOM \
michael@0:     nsresult getNameAtom(nsIAtom** aAtom);
michael@0: #else
michael@0: #define TX_DECL_TOSTRING
michael@0: #define TX_DECL_GETNAMEATOM
michael@0: #endif
michael@0: 
michael@0: #define TX_DECL_EXPR_BASE \
michael@0:     nsresult evaluate(txIEvalContext* aContext, txAExprResult** aResult); \
michael@0:     ResultType getReturnType(); \
michael@0:     bool isSensitiveTo(ContextSensitivity aContexts);
michael@0: 
michael@0: #define TX_DECL_EXPR \
michael@0:     TX_DECL_EXPR_BASE \
michael@0:     TX_DECL_TOSTRING \
michael@0:     Expr* getSubExprAt(uint32_t aPos); \
michael@0:     void setSubExprAt(uint32_t aPos, Expr* aExpr);
michael@0: 
michael@0: #define TX_DECL_OPTIMIZABLE_EXPR \
michael@0:     TX_DECL_EXPR \
michael@0:     ExprType getType();
michael@0:     
michael@0: 
michael@0: #define TX_DECL_FUNCTION \
michael@0:     TX_DECL_GETNAMEATOM \
michael@0:     TX_DECL_EXPR_BASE
michael@0: 
michael@0: #define TX_IMPL_EXPR_STUBS_BASE(_class, _ReturnType)          \
michael@0: Expr::ResultType                                              \
michael@0: _class::getReturnType()                                       \
michael@0: {                                                             \
michael@0:     return _ReturnType;                                       \
michael@0: }
michael@0: 
michael@0: #define TX_IMPL_EXPR_STUBS_0(_class, _ReturnType)             \
michael@0: TX_IMPL_EXPR_STUBS_BASE(_class, _ReturnType)                  \
michael@0: Expr*                                                         \
michael@0: _class::getSubExprAt(uint32_t aPos)                           \
michael@0: {                                                             \
michael@0:     return nullptr;                                            \
michael@0: }                                                             \
michael@0: void                                                          \
michael@0: _class::setSubExprAt(uint32_t aPos, Expr* aExpr)              \
michael@0: {                                                             \
michael@0:     NS_NOTREACHED("setting bad subexpression index");         \
michael@0: }
michael@0: 
michael@0: #define TX_IMPL_EXPR_STUBS_1(_class, _ReturnType, _Expr1)     \
michael@0: TX_IMPL_EXPR_STUBS_BASE(_class, _ReturnType)                  \
michael@0: Expr*                                                         \
michael@0: _class::getSubExprAt(uint32_t aPos)                           \
michael@0: {                                                             \
michael@0:     if (aPos == 0) {                                          \
michael@0:         return _Expr1;                                        \
michael@0:     }                                                         \
michael@0:     return nullptr;                                            \
michael@0: }                                                             \
michael@0: void                                                          \
michael@0: _class::setSubExprAt(uint32_t aPos, Expr* aExpr)              \
michael@0: {                                                             \
michael@0:     NS_ASSERTION(aPos < 1, "setting bad subexpression index");\
michael@0:     _Expr1.forget();                                          \
michael@0:     _Expr1 = aExpr;                                           \
michael@0: }
michael@0: 
michael@0: #define TX_IMPL_EXPR_STUBS_2(_class, _ReturnType, _Expr1, _Expr2) \
michael@0: TX_IMPL_EXPR_STUBS_BASE(_class, _ReturnType)                  \
michael@0: Expr*                                                         \
michael@0: _class::getSubExprAt(uint32_t aPos)                           \
michael@0: {                                                             \
michael@0:     switch(aPos) {                                            \
michael@0:         case 0:                                               \
michael@0:             return _Expr1;                                    \
michael@0:         case 1:                                               \
michael@0:             return _Expr2;                                    \
michael@0:         default:                                              \
michael@0:             break;                                            \
michael@0:     }                                                         \
michael@0:     return nullptr;                                            \
michael@0: }                                                             \
michael@0: void                                                          \
michael@0: _class::setSubExprAt(uint32_t aPos, Expr* aExpr)              \
michael@0: {                                                             \
michael@0:     NS_ASSERTION(aPos < 2, "setting bad subexpression index");\
michael@0:     if (aPos == 0) {                                          \
michael@0:         _Expr1.forget();                                      \
michael@0:         _Expr1 = aExpr;                                       \
michael@0:     }                                                         \
michael@0:     else {                                                    \
michael@0:         _Expr2.forget();                                      \
michael@0:         _Expr2 = aExpr;                                       \
michael@0:     }                                                         \
michael@0: }
michael@0: 
michael@0: #define TX_IMPL_EXPR_STUBS_LIST(_class, _ReturnType, _ExprList) \
michael@0: TX_IMPL_EXPR_STUBS_BASE(_class, _ReturnType)                  \
michael@0: Expr*                                                         \
michael@0: _class::getSubExprAt(uint32_t aPos)                           \
michael@0: {                                                             \
michael@0:     return _ExprList.SafeElementAt(aPos);                     \
michael@0: }                                                             \
michael@0: void                                                          \
michael@0: _class::setSubExprAt(uint32_t aPos, Expr* aExpr)              \
michael@0: {                                                             \
michael@0:     NS_ASSERTION(aPos < _ExprList.Length(),                   \
michael@0:                  "setting bad subexpression index");          \
michael@0:     _ExprList[aPos] = aExpr;                                  \
michael@0: }
michael@0: 
michael@0: 
michael@0: /**
michael@0:  * This class represents a FunctionCall as defined by the XPath 1.0
michael@0:  * Recommendation.
michael@0: **/
michael@0: class FunctionCall : public Expr
michael@0: {
michael@0: public:
michael@0:     /**
michael@0:      * Adds the given parameter to this FunctionCall's parameter list.
michael@0:      * The ownership of the given Expr is passed over to the FunctionCall,
michael@0:      * even on failure.
michael@0:      * @param aExpr the Expr to add to this FunctionCall's parameter list
michael@0:      * @return nsresult indicating out of memory
michael@0:      */
michael@0:     nsresult addParam(Expr* aExpr)
michael@0:     {
michael@0:         return mParams.AppendElement(aExpr) ?
michael@0:             NS_OK : NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Check if the number of parameters falls within a range.
michael@0:      *
michael@0:      * @param aParamCountMin minimum number of required parameters.
michael@0:      * @param aParamCountMax maximum number of parameters. If aParamCountMax
michael@0:      *                       is negative the maximum number is not checked.
michael@0:      * @return boolean representing whether the number of parameters falls
michael@0:      *         within the expected range or not.
michael@0:      *
michael@0:      * XXX txIEvalContext should be txIParseContest, bug 143291
michael@0:      */
michael@0:     virtual bool requireParams(int32_t aParamCountMin,
michael@0:                                  int32_t aParamCountMax,
michael@0:                                  txIEvalContext* aContext);
michael@0: 
michael@0:     TX_DECL_TOSTRING
michael@0:     Expr* getSubExprAt(uint32_t aPos) MOZ_OVERRIDE;
michael@0:     void setSubExprAt(uint32_t aPos, Expr* aExpr) MOZ_OVERRIDE;
michael@0: 
michael@0: protected:
michael@0: 
michael@0:     txOwningArray<Expr> mParams;
michael@0: 
michael@0:     /*
michael@0:      * Evaluates the given Expression and converts its result to a number.
michael@0:      */
michael@0:     static nsresult evaluateToNumber(Expr* aExpr, txIEvalContext* aContext,
michael@0:                                      double* aResult);
michael@0: 
michael@0:     /*
michael@0:      * Evaluates the given Expression and converts its result to a NodeSet.
michael@0:      * If the result is not a NodeSet an error is returned.
michael@0:      */
michael@0:     static nsresult evaluateToNodeSet(Expr* aExpr, txIEvalContext* aContext,
michael@0:                                       txNodeSet** aResult);
michael@0: 
michael@0:     /**
michael@0:      * Returns true if any argument is sensitive to the given context.
michael@0:      */
michael@0:     bool argsSensitiveTo(ContextSensitivity aContexts);
michael@0: 
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0:     /*
michael@0:      * Returns the name of the function as an atom.
michael@0:      */
michael@0:     virtual nsresult getNameAtom(nsIAtom** aAtom) = 0;
michael@0: #endif
michael@0: };
michael@0: 
michael@0: class txCoreFunctionCall : public FunctionCall
michael@0: {
michael@0: public:
michael@0: 
michael@0:     // This must be ordered in the same order as descriptTable in
michael@0:     // txCoreFunctionCall.cpp. If you change one, change the other.
michael@0:     enum eType {
michael@0:         COUNT = 0,         // count()
michael@0:         ID,                // id()
michael@0:         LAST,              // last()
michael@0:         LOCAL_NAME,        // local-name()
michael@0:         NAMESPACE_URI,     // namespace-uri()
michael@0:         NAME,              // name()
michael@0:         POSITION,          // position()
michael@0: 
michael@0:         CONCAT,            // concat()
michael@0:         CONTAINS,          // contains()
michael@0:         NORMALIZE_SPACE,   // normalize-space()
michael@0:         STARTS_WITH,       // starts-with()
michael@0:         STRING,            // string()
michael@0:         STRING_LENGTH,     // string-length()
michael@0:         SUBSTRING,         // substring()
michael@0:         SUBSTRING_AFTER,   // substring-after()
michael@0:         SUBSTRING_BEFORE,  // substring-before()
michael@0:         TRANSLATE,         // translate()
michael@0: 
michael@0:         NUMBER,            // number()
michael@0:         ROUND,             // round()
michael@0:         FLOOR,             // floor()
michael@0:         CEILING,           // ceiling()
michael@0:         SUM,               // sum()
michael@0: 
michael@0:         BOOLEAN,           // boolean()
michael@0:         _FALSE,            // false()
michael@0:         LANG,              // lang()
michael@0:         _NOT,              // not()
michael@0:         _TRUE              // true()
michael@0:     };
michael@0: 
michael@0:     /*
michael@0:      * Creates a txCoreFunctionCall of the given type
michael@0:      */
michael@0:     txCoreFunctionCall(eType aType) : mType(aType)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_FUNCTION
michael@0: 
michael@0:     static bool getTypeFromAtom(nsIAtom* aName, eType& aType);
michael@0: 
michael@0: private:
michael@0:     eType mType;
michael@0: };
michael@0: 
michael@0: 
michael@0: /*
michael@0:  * This class represents a NodeTest as defined by the XPath spec
michael@0:  */
michael@0: class txNodeTest
michael@0: {
michael@0: public:
michael@0:     txNodeTest()
michael@0:     {
michael@0:         MOZ_COUNT_CTOR(txNodeTest);
michael@0:     }
michael@0:     virtual ~txNodeTest()
michael@0:     {
michael@0:         MOZ_COUNT_DTOR(txNodeTest);
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * Virtual methods
michael@0:      * pretty much a txPattern, but not supposed to be used 
michael@0:      * standalone. The NodeTest node() is different to the
michael@0:      * Pattern "node()" (document node isn't matched)
michael@0:      */
michael@0:     virtual bool matches(const txXPathNode& aNode,
michael@0:                            txIMatchContext* aContext) = 0;
michael@0:     virtual double getDefaultPriority() = 0;
michael@0: 
michael@0:     /**
michael@0:      * Returns the type of this nodetest.
michael@0:      */
michael@0:     enum NodeTestType {
michael@0:         NAME_TEST,
michael@0:         NODETYPE_TEST,
michael@0:         OTHER_TEST
michael@0:     };
michael@0:     virtual NodeTestType getType()
michael@0:     {
michael@0:       return OTHER_TEST;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Returns true if this expression is sensitive to *any* of
michael@0:      * the requested flags.
michael@0:      */
michael@0:     virtual bool isSensitiveTo(Expr::ContextSensitivity aContext) = 0;
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0:     virtual void toString(nsAString& aDest) = 0;
michael@0: #endif
michael@0: };
michael@0: 
michael@0: #define TX_DECL_NODE_TEST \
michael@0:     TX_DECL_TOSTRING \
michael@0:     bool matches(const txXPathNode& aNode, txIMatchContext* aContext); \
michael@0:     double getDefaultPriority(); \
michael@0:     bool isSensitiveTo(Expr::ContextSensitivity aContext);
michael@0: 
michael@0: /*
michael@0:  * This class represents a NameTest as defined by the XPath spec
michael@0:  */
michael@0: class txNameTest : public txNodeTest
michael@0: {
michael@0: public:
michael@0:     /*
michael@0:      * Creates a new txNameTest with the given type and the given
michael@0:      * principal node type
michael@0:      */
michael@0:     txNameTest(nsIAtom* aPrefix, nsIAtom* aLocalName, int32_t aNSID,
michael@0:                uint16_t aNodeType);
michael@0: 
michael@0:     NodeTestType getType() MOZ_OVERRIDE;
michael@0: 
michael@0:     TX_DECL_NODE_TEST
michael@0: 
michael@0:     nsCOMPtr<nsIAtom> mPrefix;
michael@0:     nsCOMPtr<nsIAtom> mLocalName;
michael@0:     int32_t mNamespace;
michael@0: private:
michael@0:     uint16_t mNodeType;
michael@0: };
michael@0: 
michael@0: /*
michael@0:  * This class represents a NodeType as defined by the XPath spec
michael@0:  */
michael@0: class txNodeTypeTest : public txNodeTest
michael@0: {
michael@0: public:
michael@0:     enum NodeType {
michael@0:         COMMENT_TYPE,
michael@0:         TEXT_TYPE,
michael@0:         PI_TYPE,
michael@0:         NODE_TYPE
michael@0:     };
michael@0: 
michael@0:     /*
michael@0:      * Creates a new txNodeTypeTest of the given type
michael@0:      */
michael@0:     txNodeTypeTest(NodeType aNodeType)
michael@0:         : mNodeType(aNodeType)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     /*
michael@0:      * Sets the name of the node to match. Only availible for pi nodes
michael@0:      */
michael@0:     void setNodeName(const nsAString& aName)
michael@0:     {
michael@0:         mNodeName = do_GetAtom(aName);
michael@0:     }
michael@0: 
michael@0:     NodeType getNodeTestType()
michael@0:     {
michael@0:         return mNodeType;
michael@0:     }
michael@0: 
michael@0:     NodeTestType getType() MOZ_OVERRIDE;
michael@0: 
michael@0:     TX_DECL_NODE_TEST
michael@0: 
michael@0: private:
michael@0:     NodeType mNodeType;
michael@0:     nsCOMPtr<nsIAtom> mNodeName;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Class representing a nodetest combined with a predicate. May only be used
michael@0:  * if the predicate is not sensitive to the context-nodelist.
michael@0:  */
michael@0: class txPredicatedNodeTest : public txNodeTest
michael@0: {
michael@0: public:
michael@0:     txPredicatedNodeTest(txNodeTest* aNodeTest, Expr* aPredicate);
michael@0:     TX_DECL_NODE_TEST
michael@0: 
michael@0: private:
michael@0:     nsAutoPtr<txNodeTest> mNodeTest;
michael@0:     nsAutoPtr<Expr> mPredicate;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Represents an ordered list of Predicates,
michael@0:  * for use with Step and Filter Expressions
michael@0: **/
michael@0: class PredicateList  {
michael@0: public:
michael@0:     /**
michael@0:      * Adds the given Expr to the list.
michael@0:      * The ownership of the given Expr is passed over the PredicateList,
michael@0:      * even on failure.
michael@0:      * @param aExpr the Expr to add to the list
michael@0:      * @return nsresult indicating out of memory
michael@0:      */
michael@0:     nsresult add(Expr* aExpr)
michael@0:     {
michael@0:         NS_ASSERTION(aExpr, "missing expression");
michael@0:         return mPredicates.AppendElement(aExpr) ?
michael@0:             NS_OK : NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0: 
michael@0:     nsresult evaluatePredicates(txNodeSet* aNodes, txIMatchContext* aContext);
michael@0: 
michael@0:     /**
michael@0:      * Drops the first predicate without deleting it.
michael@0:      */
michael@0:     void dropFirst()
michael@0:     {
michael@0:         mPredicates.RemoveElementAt(0);
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * returns true if this predicate list is empty
michael@0:     **/
michael@0:     bool isEmpty()
michael@0:     {
michael@0:         return mPredicates.IsEmpty();
michael@0:     }
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0:     /**
michael@0:      * Returns the String representation of this PredicateList.
michael@0:      * @param dest the String to use when creating the String
michael@0:      * representation. The String representation will be appended to
michael@0:      * any data in the destination String, to allow cascading calls to
michael@0:      * other #toString() methods for Expressions.
michael@0:      * @return the String representation of this PredicateList.
michael@0:     **/
michael@0:     void toString(nsAString& dest);
michael@0: #endif
michael@0: 
michael@0: protected:
michael@0:     bool isSensitiveTo(Expr::ContextSensitivity aContext);
michael@0:     Expr* getSubExprAt(uint32_t aPos)
michael@0:     {
michael@0:         return mPredicates.SafeElementAt(aPos);
michael@0:     }
michael@0:     void setSubExprAt(uint32_t aPos, Expr* aExpr)
michael@0:     {
michael@0:         NS_ASSERTION(aPos < mPredicates.Length(),
michael@0:                      "setting bad subexpression index");
michael@0:         mPredicates[aPos] = aExpr;
michael@0:     }
michael@0: 
michael@0:     //-- list of predicates
michael@0:     txOwningArray<Expr> mPredicates;
michael@0: }; //-- PredicateList
michael@0: 
michael@0: class LocationStep : public Expr,
michael@0:                      public PredicateList
michael@0: {
michael@0: public:
michael@0:     enum LocationStepType {
michael@0:         ANCESTOR_AXIS = 0,
michael@0:         ANCESTOR_OR_SELF_AXIS,
michael@0:         ATTRIBUTE_AXIS,
michael@0:         CHILD_AXIS,
michael@0:         DESCENDANT_AXIS,
michael@0:         DESCENDANT_OR_SELF_AXIS,
michael@0:         FOLLOWING_AXIS,
michael@0:         FOLLOWING_SIBLING_AXIS,
michael@0:         NAMESPACE_AXIS,
michael@0:         PARENT_AXIS,
michael@0:         PRECEDING_AXIS,
michael@0:         PRECEDING_SIBLING_AXIS,
michael@0:         SELF_AXIS
michael@0:     };
michael@0: 
michael@0:     /**
michael@0:      * Creates a new LocationStep using the given NodeExpr and Axis Identifier
michael@0:      * @param nodeExpr the NodeExpr to use when matching Nodes
michael@0:      * @param axisIdentifier the Axis Identifier in which to search for nodes
michael@0:     **/
michael@0:     LocationStep(txNodeTest* aNodeTest,
michael@0:                  LocationStepType aAxisIdentifier)
michael@0:         : mNodeTest(aNodeTest),
michael@0:           mAxisIdentifier(aAxisIdentifier)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_OPTIMIZABLE_EXPR
michael@0: 
michael@0:     txNodeTest* getNodeTest()
michael@0:     {
michael@0:         return mNodeTest;
michael@0:     }
michael@0:     void setNodeTest(txNodeTest* aNodeTest)
michael@0:     {
michael@0:         mNodeTest.forget();
michael@0:         mNodeTest = aNodeTest;
michael@0:     }
michael@0:     LocationStepType getAxisIdentifier()
michael@0:     {
michael@0:         return mAxisIdentifier;
michael@0:     }
michael@0:     void setAxisIdentifier(LocationStepType aAxisIdentifier)
michael@0:     {
michael@0:         mAxisIdentifier = aAxisIdentifier;
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     void fromDescendants(const txXPathNode& aNode, txIMatchContext* aCs,
michael@0:                          txNodeSet* aNodes);
michael@0:     void fromDescendantsRev(const txXPathNode& aNode, txIMatchContext* aCs,
michael@0:                             txNodeSet* aNodes);
michael@0: 
michael@0:     nsAutoPtr<txNodeTest> mNodeTest;
michael@0:     LocationStepType mAxisIdentifier;
michael@0: };
michael@0: 
michael@0: class FilterExpr : public Expr,
michael@0:                    public PredicateList
michael@0: {
michael@0: public:
michael@0: 
michael@0:     /**
michael@0:      * Creates a new FilterExpr using the given Expr
michael@0:      * @param expr the Expr to use for evaluation
michael@0:      */
michael@0:     FilterExpr(Expr* aExpr)
michael@0:         : expr(aExpr)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsAutoPtr<Expr> expr;
michael@0: 
michael@0: }; //-- FilterExpr
michael@0: 
michael@0: 
michael@0: class txLiteralExpr : public Expr {
michael@0: public:
michael@0:     txLiteralExpr(double aDbl)
michael@0:         : mValue(new NumberResult(aDbl, nullptr))
michael@0:     {
michael@0:     }
michael@0:     txLiteralExpr(const nsAString& aStr)
michael@0:         : mValue(new StringResult(aStr, nullptr))
michael@0:     {
michael@0:     }
michael@0:     txLiteralExpr(txAExprResult* aValue)
michael@0:         : mValue(aValue)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsRefPtr<txAExprResult> mValue;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * Represents an UnaryExpr. Returns the negative value of its expr.
michael@0: **/
michael@0: class UnaryExpr : public Expr {
michael@0: 
michael@0: public:
michael@0: 
michael@0:     UnaryExpr(Expr* aExpr)
michael@0:         : expr(aExpr)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsAutoPtr<Expr> expr;
michael@0: }; //-- UnaryExpr
michael@0: 
michael@0: /**
michael@0:  * Represents a BooleanExpr, a binary expression that
michael@0:  * performs a boolean operation between its lvalue and rvalue.
michael@0: **/
michael@0: class BooleanExpr : public Expr
michael@0: {
michael@0: public:
michael@0: 
michael@0:     //-- BooleanExpr Types
michael@0:     enum _BooleanExprType { AND = 1, OR };
michael@0: 
michael@0:      BooleanExpr(Expr* aLeftExpr, Expr* aRightExpr, short aOp)
michael@0:          : leftExpr(aLeftExpr),
michael@0:            rightExpr(aRightExpr),
michael@0:            op(aOp)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsAutoPtr<Expr> leftExpr, rightExpr;
michael@0:     short op;
michael@0: }; //-- BooleanExpr
michael@0: 
michael@0: /**
michael@0:  * Represents a MultiplicativeExpr, a binary expression that
michael@0:  * performs a multiplicative operation between its lvalue and rvalue:
michael@0:  *  *   : multiply
michael@0:  * mod  : modulus
michael@0:  * div  : divide
michael@0:  *
michael@0: **/
michael@0: class txNumberExpr : public Expr
michael@0: {
michael@0: public:
michael@0: 
michael@0:     enum eOp { ADD, SUBTRACT, DIVIDE, MULTIPLY, MODULUS };
michael@0: 
michael@0:     txNumberExpr(Expr* aLeftExpr, Expr* aRightExpr, eOp aOp)
michael@0:         : mLeftExpr(aLeftExpr),
michael@0:           mRightExpr(aRightExpr),
michael@0:           mOp(aOp)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsAutoPtr<Expr> mLeftExpr, mRightExpr;
michael@0:     eOp mOp;
michael@0: }; //-- MultiplicativeExpr
michael@0: 
michael@0: /**
michael@0:  * Represents a RelationalExpr, an expression that compares its lvalue
michael@0:  * to its rvalue using:
michael@0:  * =  : equal to
michael@0:  * <  : less than
michael@0:  * >  : greater than
michael@0:  * <= : less than or equal to
michael@0:  * >= : greater than or equal to
michael@0:  *
michael@0: **/
michael@0: class RelationalExpr : public Expr
michael@0: {
michael@0: public:
michael@0:     enum RelationalExprType {
michael@0:         EQUAL,
michael@0:         NOT_EQUAL,
michael@0:         LESS_THAN,
michael@0:         GREATER_THAN,
michael@0:         LESS_OR_EQUAL,
michael@0:         GREATER_OR_EQUAL
michael@0:     };
michael@0: 
michael@0:     RelationalExpr(Expr* aLeftExpr, Expr* aRightExpr, RelationalExprType aOp)
michael@0:         : mLeftExpr(aLeftExpr),
michael@0:           mRightExpr(aRightExpr),
michael@0:           mOp(aOp)
michael@0:     {
michael@0:     }
michael@0: 
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     bool compareResults(txIEvalContext* aContext, txAExprResult* aLeft,
michael@0:                           txAExprResult* aRight);
michael@0: 
michael@0:     nsAutoPtr<Expr> mLeftExpr;
michael@0:     nsAutoPtr<Expr> mRightExpr;
michael@0:     RelationalExprType mOp;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * VariableRefExpr
michael@0:  * Represents a variable reference ($refname)
michael@0: **/
michael@0: class VariableRefExpr : public Expr {
michael@0: 
michael@0: public:
michael@0: 
michael@0:     VariableRefExpr(nsIAtom* aPrefix, nsIAtom* aLocalName, int32_t aNSID);
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     nsCOMPtr<nsIAtom> mPrefix;
michael@0:     nsCOMPtr<nsIAtom> mLocalName;
michael@0:     int32_t mNamespace;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  *  Represents a PathExpr
michael@0: **/
michael@0: class PathExpr : public Expr {
michael@0: 
michael@0: public:
michael@0: 
michael@0:     //-- Path Operators
michael@0:     //-- RELATIVE_OP is the default
michael@0:     //-- LF, changed from static const short to enum
michael@0:     enum PathOperator { RELATIVE_OP, DESCENDANT_OP };
michael@0: 
michael@0:     /**
michael@0:      * Adds the Expr to this PathExpr
michael@0:      * The ownership of the given Expr is passed over the PathExpr,
michael@0:      * even on failure.
michael@0:      * @param aExpr the Expr to add to this PathExpr
michael@0:      * @return nsresult indicating out of memory
michael@0:      */
michael@0:     nsresult addExpr(Expr* aExpr, PathOperator pathOp);
michael@0: 
michael@0:     /**
michael@0:      * Removes and deletes the expression at the given index.
michael@0:      */
michael@0:     void deleteExprAt(uint32_t aPos)
michael@0:     {
michael@0:         NS_ASSERTION(aPos < mItems.Length(),
michael@0:                      "killing bad expression index");
michael@0:         mItems.RemoveElementAt(aPos);
michael@0:     }
michael@0: 
michael@0:     TX_DECL_OPTIMIZABLE_EXPR
michael@0: 
michael@0:     PathOperator getPathOpAt(uint32_t aPos)
michael@0:     {
michael@0:         NS_ASSERTION(aPos < mItems.Length(), "getting bad pathop index");
michael@0:         return mItems[aPos].pathOp;
michael@0:     }
michael@0:     void setPathOpAt(uint32_t aPos, PathOperator aPathOp)
michael@0:     {
michael@0:         NS_ASSERTION(aPos < mItems.Length(), "setting bad pathop index");
michael@0:         mItems[aPos].pathOp = aPathOp;
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     class PathExprItem {
michael@0:     public:
michael@0:         nsAutoPtr<Expr> expr;
michael@0:         PathOperator pathOp;
michael@0:     };
michael@0: 
michael@0:     nsTArray<PathExprItem> mItems;
michael@0: 
michael@0:     /*
michael@0:      * Selects from the descendants of the context node
michael@0:      * all nodes that match the Expr
michael@0:      */
michael@0:     nsresult evalDescendants(Expr* aStep, const txXPathNode& aNode,
michael@0:                              txIMatchContext* aContext,
michael@0:                              txNodeSet* resNodes);
michael@0: };
michael@0: 
michael@0: /**
michael@0:  * This class represents a RootExpr, which only matches the Document node
michael@0: **/
michael@0: class RootExpr : public Expr {
michael@0: public:
michael@0:     /**
michael@0:      * Creates a new RootExpr
michael@0:      */
michael@0:     RootExpr()
michael@0: #ifdef TX_TO_STRING
michael@0:         : mSerialize(true)
michael@0: #endif
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0: public:
michael@0:     void setSerialize(bool aSerialize)
michael@0:     {
michael@0:         mSerialize = aSerialize;
michael@0:     }
michael@0: 
michael@0: private:
michael@0:     // When a RootExpr is used in a PathExpr it shouldn't be serialized
michael@0:     bool mSerialize;
michael@0: #endif
michael@0: }; //-- RootExpr
michael@0: 
michael@0: /**
michael@0:  *  Represents a UnionExpr
michael@0: **/
michael@0: class UnionExpr : public Expr {
michael@0: public:
michael@0:     /**
michael@0:      * Adds the PathExpr to this UnionExpr
michael@0:      * The ownership of the given Expr is passed over the UnionExpr,
michael@0:      * even on failure.
michael@0:      * @param aExpr the Expr to add to this UnionExpr
michael@0:      * @return nsresult indicating out of memory
michael@0:      */
michael@0:     nsresult addExpr(Expr* aExpr)
michael@0:     {
michael@0:         return mExpressions.AppendElement(aExpr) ?
michael@0:             NS_OK : NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0: 
michael@0:     /**
michael@0:      * Removes and deletes the expression at the given index.
michael@0:      */
michael@0:     void deleteExprAt(uint32_t aPos)
michael@0:     {
michael@0:         NS_ASSERTION(aPos < mExpressions.Length(),
michael@0:                      "killing bad expression index");
michael@0: 
michael@0:         delete mExpressions[aPos];
michael@0:         mExpressions.RemoveElementAt(aPos);
michael@0:     }
michael@0: 
michael@0:     TX_DECL_OPTIMIZABLE_EXPR
michael@0: 
michael@0: private:
michael@0: 
michael@0:    txOwningArray<Expr> mExpressions;
michael@0: 
michael@0: }; //-- UnionExpr
michael@0: 
michael@0: /**
michael@0:  * Class specializing in executing expressions like "@foo" where we are
michael@0:  * interested in different result-types, and expressions like "@foo = 'hi'"
michael@0:  */
michael@0: class txNamedAttributeStep : public Expr
michael@0: {
michael@0: public:
michael@0:     txNamedAttributeStep(int32_t aNsID, nsIAtom* aPrefix,
michael@0:                          nsIAtom* aLocalName);
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: private:
michael@0:     int32_t mNamespace;
michael@0:     nsCOMPtr<nsIAtom> mPrefix;
michael@0:     nsCOMPtr<nsIAtom> mLocalName;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  *
michael@0:  */
michael@0: class txUnionNodeTest : public txNodeTest
michael@0: {
michael@0: public:
michael@0:     nsresult addNodeTest(txNodeTest* aNodeTest)
michael@0:     {
michael@0:         return mNodeTests.AppendElement(aNodeTest) ?
michael@0:             NS_OK : NS_ERROR_OUT_OF_MEMORY;
michael@0:     }
michael@0: 
michael@0:     TX_DECL_NODE_TEST
michael@0: 
michael@0: private:
michael@0:     txOwningArray<txNodeTest> mNodeTests;
michael@0: };
michael@0: 
michael@0: /**
michael@0:  *  Expression that failed to parse
michael@0:  */
michael@0: class txErrorExpr : public Expr
michael@0: {
michael@0: public:
michael@0: #ifdef TX_TO_STRING
michael@0:     txErrorExpr(const nsAString& aStr)
michael@0:       : mStr(aStr)
michael@0:     {
michael@0:     }
michael@0: #endif
michael@0: 
michael@0:     TX_DECL_EXPR
michael@0: 
michael@0: #ifdef TX_TO_STRING
michael@0: private:
michael@0:     nsString mStr;
michael@0: #endif
michael@0: };
michael@0: 
michael@0: #endif
michael@0: 
michael@0: