Changes related to history listener interface 65608 r=valeski sr=rpotts

xpfe/components/shistory/public/MANIFEST_IDL

@@ -1,4 +1,5 @@
 nsIShEntry.idl   \
 nsISHTransaction.idl \
 nsISHContainer.idl  \
-nsISHistory.idl 
+nsISHistory.idl \
+nsISHistoryListener.idl

xpfe/components/shistory/public/Makefile.in

@@ -32,6 +32,7 @@ XPIDLSRCS	= nsISHEntry.idl        \
             nsISHContainer.idl    \
             nsISHTransaction.idl  \
             nsISHistory.idl       \
+            nsISHistoryListener.idl   \
                   $(NULL)
 
 include $(topsrcdir)/config/rules.mk

xpfe/components/shistory/public/makefile.win

@@ -28,6 +28,7 @@ XPIDLSRCS =                   \
     .\nsISHContainer.idl      \
     .\nsISHTransaction.idl    \
     .\nsISHistory.idl         \
+    .\nsISHistoryListener.idl \
     $(NULL)
 
 include <$(DEPTH)\config\rules.mak>

xpfe/components/shistory/public/nsISHistory.idl

@@ -25,8 +25,8 @@
 #include "nsISHEntry.idl"
 #include "nsISHTransaction.idl"
 #include "nsIDocShell.idl"
+#include "nsISHistoryListener.idl"
 
-//interface nsIDocShell;
 
 %{C++
 #define NS_SHISTORY_CID \
@@ -40,10 +40,10 @@ interface nsISHistory: nsISupports
 {
   /**
    * Add a new Entry to the History List
-	* @param aEntry - The entry to add
-	* @param aPersist - If true this specifies that the entry should persist
-	* in the list.  If false, this means that when new entries are added
-	* this element will not appear in the session history list.
+	 * @param aEntry - The entry to add
+	 * @param aPersist - If true this specifies that the entry should persist
+	 * in the list.  If false, this means that when new entries are added
+	 * this element will not appear in the session history list.
    */
    void  addEntry(in nsISHEntry aEntry, in boolean aPersist);
 
@@ -92,4 +92,14 @@ interface nsISHistory: nsISupports
    */
    void PurgeHistory(in long numEntries);
 
+  /**
+   * Register a Session History Listener to be notified on SHistory events
+   */
+   void addSHistoryListener(in nsISHistoryListener aListener);
+
+  /**
+   * Remove a previously registered Session History Listener 
+   */
+   void removeSHistoryListener(in nsISHistoryListener aListener);
+
 };

xpfe/components/shistory/src/nsSHistory.cpp

@@ -113,6 +113,16 @@ nsSHistory::AddEntry(nsISHEntry * aSHEntry, PRBool aPersist)
   nsCOMPtr<nsISHTransaction> txn(do_CreateInstance(NS_SHTRANSACTION_CONTRACTID));
   NS_ENSURE_TRUE(txn, NS_ERROR_FAILURE);
 
+  // Notify any listener about the new addition
+  if (mListener) {
+    nsCOMPtr<nsISHistoryListener> listener(do_QueryInterface(mListener));
+    if (listener) {
+      nsCOMPtr<nsIURI> uri;
+      aSHEntry->GetURI(getter_AddRefs(uri));
+      listener->OnHistoryNewEntry(uri);
+    }
+  }
+
   // Set the ShEntry and parent for the transaction. setting the 
   // parent will properly set the parent child relationship
   txn->SetPersist(aPersist);
@@ -346,7 +356,21 @@ nsSHistory::PurgeHistory(PRInt32 aEntries)
   if (mLength <= 0 || aEntries <= 0)
     return NS_ERROR_FAILURE;
         
-  PRInt32 cnt = 0;    
+  PRBool purgeHistory = PR_TRUE;
+  // Notify the listener about the history purge
+  if (mListener) {
+    nsCOMPtr<nsISHistoryListener> listener(do_QueryInterface(mListener));
+    if (listener) {
+      listener->OnHistoryPurge(aEntries, &purgeHistory);
+    } 
+  }
+
+  if (!purgeHistory) {
+    // Listener asked us not to purge
+    return NS_OK;
+  }
+
+  PRInt32 cnt = 0;
   while (cnt < aEntries) {
     nsCOMPtr<nsISHTransaction>  txn = mListRoot;
     nsCOMPtr<nsISHTransaction> nextTxn;
@@ -361,6 +385,29 @@ nsSHistory::PurgeHistory(PRInt32 aEntries)
   return NS_OK;
 }
 
+
+NS_IMETHODIMP
+nsSHistory::AddSHistoryListener(nsISHistoryListener * aListener)
+{
+  NS_ENSURE_ARG_POINTER(aListener);
+
+  // Check if the listener supports Weak Reference. This is a must.
+  // This listener functionality is used by embedders and we want to 
+  // have the right ownership with who ever listens to SHistory
+  nsWeakPtr listener = getter_AddRefs(NS_GetWeakReference(aListener));
+  if (!listener) return NS_ERROR_FAILURE;
+  mListener = listener;
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP
+nsSHistory::RemoveSHistoryListener(nsISHistoryListener * aListener)
+{
+  mListener = nsnull;
+  return NS_OK;
+}
+
 //*****************************************************************************
 //    nsSHistory: nsIWebNavigation
 //*****************************************************************************
@@ -405,7 +452,7 @@ nsSHistory::GoBack()
 	GetCanGoBack(&canGoBack);
 	if (!canGoBack)  // Can't go back
 		return NS_ERROR_UNEXPECTED;
-    return GotoIndex(mIndex-1);
+  return GotoIndex(mIndex-1);
 }
 
 
@@ -417,13 +464,14 @@ nsSHistory::GoForward()
 	GetCanGoForward(&canGoForward);
 	if (!canGoForward)  // Can't go forward
 		return NS_ERROR_UNEXPECTED;
-    return GotoIndex(mIndex+1);
+  return GotoIndex(mIndex+1);
 
 }
 
 NS_IMETHODIMP
 nsSHistory::Reload(PRUint32 aReloadFlags)
 {
+  nsresult rv;
 	nsDocShellInfoLoadType loadType;
 	if (aReloadFlags & nsIWebNavigation::LOAD_FLAGS_BYPASS_PROXY && 
 	    aReloadFlags & nsIWebNavigation::LOAD_FLAGS_BYPASS_CACHE)
@@ -442,7 +490,25 @@ nsSHistory::Reload(PRUint32 aReloadFlags)
 	{
 		loadType = nsIDocShellLoadInfo::loadReloadNormal;
 	}
-	return LoadEntry(mIndex, PR_TRUE, loadType);
+  
+  // Notify listeners
+  PRBool canNavigate = PR_TRUE;
+  if (mListener) {
+    nsCOMPtr<nsISHistoryListener> listener(do_QueryInterface(mListener));
+    // We are reloading. Send Reload notifications. 
+    // nsDocShellLoadFlagType is not public, where as nsIWebNavigation
+    // is public. So send the reload notifications with the
+    // nsIWebNavigation flags. 
+    if (listener) {
+      nsCOMPtr<nsIURI> currentURI;
+      rv = GetCurrentURI(getter_AddRefs(currentURI));
+      listener->OnHistoryReload(currentURI, aReloadFlags, &canNavigate);
+    }
+  }
+  if (!canNavigate)
+    return NS_OK;
+
+	return LoadEntry(mIndex, loadType);
 }
 
 NS_IMETHODIMP
@@ -463,12 +529,15 @@ nsSHistory::GetDocument(nsIDOMDocument** aDocument)
 
 
 NS_IMETHODIMP
-nsSHistory::GetCurrentURI(nsIURI** aCurrentURI)
+nsSHistory::GetCurrentURI(nsIURI** aResultURI)
 {
-  // Not implemented
-  return NS_OK;
-}
+  NS_ENSURE_ARG_POINTER(aResultURI);
 
+  nsCOMPtr<nsISHEntry> currentEntry;
+  nsresult rv = GetEntryAtIndex(mIndex, PR_FALSE, getter_AddRefs(currentEntry));
+  if (NS_FAILED(rv) && !currentEntry) return rv;
+  return currentEntry->GetURI(aResultURI);
+}
 
 
 NS_IMETHODIMP
@@ -496,11 +565,11 @@ nsSHistory::LoadURI(const PRUnichar* aURI, PRUint32 aLoadFlags)
 NS_IMETHODIMP
 nsSHistory::GotoIndex(PRInt32 aIndex)
 {
-	return LoadEntry(aIndex, PR_FALSE, nsIDocShellLoadInfo::loadHistory);
+	return LoadEntry(aIndex, nsIDocShellLoadInfo::loadHistory);
 }
 
 NS_IMETHODIMP
-nsSHistory::LoadEntry(PRInt32 aIndex, PRBool aReloadFlag, long aLoadType)
+nsSHistory::LoadEntry(PRInt32 aIndex, long aLoadType)
 {
    nsCOMPtr<nsIDocShell> docShell;
    nsCOMPtr<nsISHEntry> shEntry;
@@ -513,6 +582,35 @@ nsSHistory::LoadEntry(PRInt32 aIndex, PRBool aReloadFlag, long aLoadType)
    nsCOMPtr<nsISHEntry> nextEntry;
    GetEntryAtIndex(mIndex, PR_FALSE, getter_AddRefs(nextEntry));
 
+  // Send appropriate listener notifications
+  PRBool canNavigate = PR_TRUE;
+  if(mListener) {
+    nsCOMPtr<nsIURI> uri;
+    nextEntry->GetURI(getter_AddRefs(uri));
+    nsCOMPtr<nsISHistoryListener> listener(do_QueryInterface(mListener));
+    if (listener) {
+      if (mIndex+1 == oldIndex) {
+        // We are going back one entry. Send GoBack notifications
+        listener->OnHistoryGoBack(uri, &canNavigate);
+      }
+      else if (mIndex-1 == oldIndex) {
+        // We are going forward. Send GoForward notification
+        listener->OnHistoryGoForward(uri, &canNavigate);
+      }
+      else if (mIndex != oldIndex) {
+        // We are going somewhere else. This is not reload either
+        listener->OnHistoryGotoIndex(mIndex, uri, &canNavigate);
+      }
+    }
+  }
+
+  if (!canNavigate) {
+    // reset the index back to what it was, if the listener
+    // asked us not to proceed with the operation.
+    mIndex = oldIndex;
+    return NS_OK;  // XXX Maybe I can return some other error code?
+  }
+
    nsCOMPtr<nsIURI> nexturi;
    PRInt32 pCount=0, nCount=0;
    nsCOMPtr<nsISHContainer> prevAsContainer(do_QueryInterface(prevEntry));

xpfe/components/shistory/src/nsSHistory.h

@@ -30,6 +30,7 @@
 #include "nsISHistory.h"
 #include "nsISHTransaction.h"
 #include "nsIWebNavigation.h"
+#include "nsIWeakReference.h"
 
 class nsIDocShell;
 
@@ -54,12 +55,14 @@ protected:
    NS_IMETHOD GetTransactionAtIndex(PRInt32 aIndex, nsISHTransaction ** aResult);
    PRBool CompareSHEntry(nsISHEntry * prevEntry, nsISHEntry * nextEntry, nsIDocShell * rootDocShell,
 	                     nsIDocShell ** aResultDocShell, nsISHEntry ** aResultSHEntry);
-   NS_IMETHOD LoadEntry(PRInt32 aIndex, PRBool aReloadFlag, long aLoadType);
+   NS_IMETHOD LoadEntry(PRInt32 aIndex, long aLoadType);
 	
 protected:
   nsCOMPtr<nsISHTransaction> mListRoot;
   PRInt32 mIndex;
   PRInt32 mLength;
+  // Session History listener
+  nsWeakPtr mListener;
   // Weak reference. Do not refcount this.
   nsIDocShell *  mRootDocShell;
 };