michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0:  *
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 nsSHistory_h
michael@0: #define nsSHistory_h
michael@0: 
michael@0: // Helper Classes
michael@0: #include "nsCOMPtr.h"
michael@0: 
michael@0: //Interfaces Needed
michael@0: #include "nsISHistory.h"
michael@0: #include "nsISHistoryInternal.h"
michael@0: #include "nsIWebNavigation.h"
michael@0: #include "nsISimpleEnumerator.h"
michael@0: #include "nsTObserverArray.h"
michael@0: #include "nsWeakPtr.h"
michael@0: 
michael@0: // Needed to maintain global list of all SHistory objects
michael@0: #include "prclist.h"
michael@0: 
michael@0: class nsIDocShell;
michael@0: class nsSHEnumerator;
michael@0: class nsSHistoryObserver;
michael@0: class nsISHEntry;
michael@0: class nsISHTransaction;
michael@0: 
michael@0: class nsSHistory: public PRCList,
michael@0:                   public nsISHistory,
michael@0:                   public nsISHistoryInternal,
michael@0:                   public nsIWebNavigation
michael@0: {
michael@0: public:
michael@0:   nsSHistory();
michael@0: 
michael@0:   NS_DECL_ISUPPORTS
michael@0:   NS_DECL_NSISHISTORY
michael@0:   NS_DECL_NSISHISTORYINTERNAL
michael@0:   NS_DECL_NSIWEBNAVIGATION
michael@0: 
michael@0:   // One time initialization method called upon docshell module construction
michael@0:   static nsresult Startup();
michael@0:   static void Shutdown();
michael@0:   static void UpdatePrefs();
michael@0: 
michael@0:   // Max number of total cached content viewers.  If the pref
michael@0:   // browser.sessionhistory.max_total_viewers is negative, then
michael@0:   // this value is calculated based on the total amount of memory.
michael@0:   // Otherwise, it comes straight from the pref.
michael@0:   static uint32_t GetMaxTotalViewers() { return sHistoryMaxTotalViewers; }
michael@0: 
michael@0: protected:
michael@0:   virtual ~nsSHistory();
michael@0:   friend class nsSHEnumerator;
michael@0:   friend class nsSHistoryObserver;
michael@0: 
michael@0:    // Could become part of nsIWebNavigation
michael@0:    NS_IMETHOD GetTransactionAtIndex(int32_t aIndex, nsISHTransaction ** aResult);
michael@0:    nsresult CompareFrames(nsISHEntry * prevEntry, nsISHEntry * nextEntry, nsIDocShell * rootDocShell, long aLoadType, bool * aIsFrameFound);
michael@0:    nsresult InitiateLoad(nsISHEntry * aFrameEntry, nsIDocShell * aFrameDS, long aLoadType);
michael@0: 
michael@0:    NS_IMETHOD LoadEntry(int32_t aIndex, long aLoadType, uint32_t histCmd);
michael@0: 
michael@0: #ifdef DEBUG
michael@0:    nsresult PrintHistory();
michael@0: #endif
michael@0: 
michael@0:   // Evict content viewers in this window which don't lie in the "safe" range
michael@0:   // around aIndex.
michael@0:   void EvictOutOfRangeWindowContentViewers(int32_t aIndex);
michael@0:   static void GloballyEvictContentViewers();
michael@0:   static void GloballyEvictAllContentViewers();
michael@0: 
michael@0:   // Calculates a max number of total
michael@0:   // content viewers to cache, based on amount of total memory
michael@0:   static uint32_t CalcMaxTotalViewers();
michael@0: 
michael@0:   void RemoveDynEntries(int32_t aOldIndex, int32_t aNewIndex);
michael@0: 
michael@0:   nsresult LoadNextPossibleEntry(int32_t aNewIndex, long aLoadType, uint32_t aHistCmd);
michael@0: protected:
michael@0:   // aIndex is the index of the transaction which may be removed.
michael@0:   // If aKeepNext is true, aIndex is compared to aIndex + 1,
michael@0:   // otherwise comparison is done to aIndex - 1.
michael@0:   bool RemoveDuplicate(int32_t aIndex, bool aKeepNext);
michael@0: 
michael@0:   nsCOMPtr<nsISHTransaction> mListRoot;
michael@0:   int32_t mIndex;
michael@0:   int32_t mLength;
michael@0:   int32_t mRequestedIndex;
michael@0:   // Session History listeners
michael@0:   nsAutoTObserverArray<nsWeakPtr, 2> mListeners;
michael@0:   // Weak reference. Do not refcount this.
michael@0:   nsIDocShell *  mRootDocShell;
michael@0: 
michael@0:   // Max viewers allowed total, across all SHistory objects
michael@0:   static int32_t  sHistoryMaxTotalViewers;
michael@0: };
michael@0: //*****************************************************************************
michael@0: //***    nsSHEnumerator: Object Management
michael@0: //*****************************************************************************
michael@0: class nsSHEnumerator : public nsISimpleEnumerator
michael@0: {
michael@0: public:
michael@0: 
michael@0:   NS_DECL_ISUPPORTS
michael@0:   NS_DECL_NSISIMPLEENUMERATOR
michael@0: 
michael@0:   nsSHEnumerator(nsSHistory *  aHistory);
michael@0:   
michael@0: protected:
michael@0:   friend class nsSHistory;
michael@0:   virtual ~nsSHEnumerator();
michael@0: private:
michael@0:   int32_t     mIndex;
michael@0:   nsSHistory *  mSHistory;  
michael@0: };
michael@0: 
michael@0: #endif   /* nsSHistory */