/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* 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/. */ /* * a class that walks the lexicographic tree of rule nodes as style * rules are matched */ #ifndef nsRuleWalker_h_ #define nsRuleWalker_h_ #include "nsRuleNode.h" #include "nsIStyleRule.h" #include "Declaration.h" #include "nsQueryObject.h" class nsRuleWalker { public: nsRuleNode* CurrentNode() { return mCurrent; } void SetCurrentNode(nsRuleNode* aNode) { NS_ASSERTION(aNode, "Must have node here!"); mCurrent = aNode; } nsPresContext* PresContext() const { return mRoot->PresContext(); } protected: void DoForward(nsIStyleRule* aRule) { mCurrent = mCurrent->Transition(aRule, mLevel, mImportance); NS_POSTCONDITION(mCurrent, "Transition messed up"); } public: void Forward(nsIStyleRule* aRule) { NS_PRECONDITION(!RefPtr<mozilla::css::Declaration>(do_QueryObject(aRule)), "Calling the wrong Forward() overload"); DoForward(aRule); } void Forward(mozilla::css::Declaration* aRule) { DoForward(aRule); mCheckForImportantRules = mCheckForImportantRules && !aRule->HasImportantData(); } // ForwardOnPossiblyCSSRule should only be used by callers that have // an explicit list of rules they need to walk, with the list // already containing any important rules they care about. void ForwardOnPossiblyCSSRule(nsIStyleRule* aRule) { DoForward(aRule); } void Reset() { mCurrent = mRoot; } bool AtRoot() { return mCurrent == mRoot; } void SetLevel(mozilla::SheetType aLevel, bool aImportance, bool aCheckForImportantRules) { NS_ASSERTION(!aCheckForImportantRules || !aImportance, "Shouldn't be checking for important rules while walking " "important rules"); mLevel = aLevel; mImportance = aImportance; mCheckForImportantRules = aCheckForImportantRules; } mozilla::SheetType GetLevel() const { return mLevel; } bool GetImportance() const { return mImportance; } bool GetCheckForImportantRules() const { return mCheckForImportantRules; } bool AuthorStyleDisabled() const { return mAuthorStyleDisabled; } // We define the visited-relevant link to be the link that is the // nearest self-or-ancestor to the node being matched. enum VisitedHandlingType { // Do rule matching as though all links are unvisited. eRelevantLinkUnvisited, // Do rule matching as though the relevant link is visited and all // other links are unvisited. eRelevantLinkVisited, // Do rule matching as though a rule should match if it would match // given any set of visitedness states. (used by users other than // nsRuleWalker) eLinksVisitedOrUnvisited }; private: nsRuleNode* mCurrent; // Our current position. Never null. nsRuleNode* mRoot; // The root of the tree we're walking. mozilla::SheetType mLevel; bool mImportance; bool mCheckForImportantRules; // If true, check for important rules as // we walk and set to false if we find // one. bool mAuthorStyleDisabled; public: nsRuleWalker(nsRuleNode* aRoot, bool aAuthorStyleDisabled) : mCurrent(aRoot) , mRoot(aRoot) , mAuthorStyleDisabled(aAuthorStyleDisabled) { NS_ASSERTION(mCurrent, "Caller screwed up and gave us null node"); MOZ_COUNT_CTOR(nsRuleWalker); } ~nsRuleWalker() { MOZ_COUNT_DTOR(nsRuleWalker); } }; #endif /* !defined(nsRuleWalker_h_) */