From 581e892d94a7bd59c0b0ffa85da38e6f4f0f2cc0 Mon Sep 17 00:00:00 2001
From: csoler <csoler@users.sourceforge.net>
Date: Mon, 26 Nov 2018 21:18:28 +0100
Subject: [PATCH] create an index iterator in ForumModel

---
 .../src/gui/gxsforums/GxsForumModel.cpp       | 88 +++++++++++++++++--
 .../src/gui/gxsforums/GxsForumModel.h         | 19 ++++
 2 files changed, 99 insertions(+), 8 deletions(-)

diff --git a/retroshare-gui/src/gui/gxsforums/GxsForumModel.cpp b/retroshare-gui/src/gui/gxsforums/GxsForumModel.cpp
index 9a8a0005f..a8729f480 100644
--- a/retroshare-gui/src/gui/gxsforums/GxsForumModel.cpp
+++ b/retroshare-gui/src/gui/gxsforums/GxsForumModel.cpp
@@ -1040,22 +1040,94 @@ QModelIndex RsGxsForumModel::getIndexOfMessage(const RsGxsMessageId& mid) const
 
 QModelIndex RsGxsForumModel::getNextIndex(const QModelIndex& i,bool unread_only) const
 {
-#ifdef TODO
     ForumModelIndex fmi ;
     convertRefPointerToTabEntry(i.internalPointer(),fmi);
 
     // Algorithm is simple: visit children recursively. When none available, go to parent. We need of course a stack of parents to the current index.
 
-    std::list<ForumModelIndex> parent_stack ;
+    const_iterator it(*this,fmi);
 
-    for(ForumModelIndex tmp(fmi);tmp!=0;tmp=mPosts[tmp].mParent)
-        parent_stack.push_front(tmp);
+    do {++it;} while(bool(it) && (!unread_only || IS_MSG_UNREAD(mPosts[*it].mMsgStatus)));
 
-	// now get to next unread item
+    if(!it)
+        return QModelIndex();
 
-    if(!mPosts[fmi].mChildren.empty())
-#endif
-		return QModelIndex();
+    void *ref ;
+    convertTabEntryToRefPointer(*it,ref);
+
+    return createIndex(mPosts[*it].prow,0,ref);
+}
+
+
+RsGxsForumModel::const_iterator::const_iterator(const RsGxsForumModel &Model, ForumModelIndex i)
+	: model(Model)
+{
+    if(i >= model.mPosts.size())
+    {
+        std::cerr << "(EE) constructed a RsGxsForumModel::const_iterator from invalid index " << i << std::endl;
+        kid = -1;
+        return;
+    }
+    // create a stack or parents
+    parent_stack.clear();
+
+    if(i==0)
+    {
+        current_parent = 0;
+        kid =0;
+        return;
+    }
+    current_parent = model.mPosts[i].mParent;
+    ForumModelIndex j(i);
+    kid = model.mPosts[i].prow;
+
+    while(j != 0)
+    {
+        parent_stack.push_front(model.mPosts[j].prow);
+		j = model.mPosts[i].mParent;
+    }
+}
+
+ForumModelIndex RsGxsForumModel::const_iterator::operator*() const
+{
+    if(current_parent >= model.mPosts.size() || kid < 0 || kid >= (int)model.mPosts[current_parent].mChildren.size())
+    {
+        std::cerr << "(EE) operator* on an invalid RsGxsForumModel::const_iterator"<< std::endl;
+        return 0;
+    }
+
+    return model.mPosts[current_parent].mChildren[kid];
+}
+
+void RsGxsForumModel::const_iterator::operator++()
+{
+    kid++;
+    while(kid >= (int)model.mPosts[current_parent].mChildren.size())
+    {
+        current_parent = model.mPosts[current_parent].mParent;
+        kid = parent_stack.back()+1;
+
+        parent_stack.pop_back();
+
+    }
+
+	if(current_parent == 0 && kid >= (int)model.mPosts[current_parent].mChildren.size())
+	{
+		kid = -1;
+		return;
+	}
+
+    while(!model.mPosts[model.mPosts[current_parent].mChildren[kid]].mChildren.empty())
+    {
+        parent_stack.push_back(kid);
+        current_parent = model.mPosts[current_parent].mChildren[kid];
+        kid = 0;
+    }
+}
+
+RsGxsForumModel::const_iterator::operator bool() const
+{
+    return kid >= 0;
 }
 
 void RsGxsForumModel::debug_dump()
diff --git a/retroshare-gui/src/gui/gxsforums/GxsForumModel.h b/retroshare-gui/src/gui/gxsforums/GxsForumModel.h
index 9f3468e7f..71218c8e8 100644
--- a/retroshare-gui/src/gui/gxsforums/GxsForumModel.h
+++ b/retroshare-gui/src/gui/gxsforums/GxsForumModel.h
@@ -83,6 +83,23 @@ public:
 	QModelIndex getIndexOfMessage(const RsGxsMessageId& mid) const;
     QModelIndex getNextIndex(const QModelIndex& i,bool unread_only) const;
 
+    class const_iterator
+    {
+    public:
+        const_iterator(const RsGxsForumModel& Model,ForumModelIndex = 0) ;
+
+        ForumModelIndex operator*() const ;
+        void operator++();
+
+        inline operator bool() const ;
+
+    private:
+        std::list<ForumModelIndex> parent_stack;
+        int kid;
+        ForumModelIndex current_parent;
+        const RsGxsForumModel& model;
+    };
+
     // This method will asynchroneously update the data
 	void setForum(const RsGxsGroupId& forumGroup);
 
@@ -160,4 +177,6 @@ private:
     QColor mTextColorUnreadChildren;
     QColor mTextColorNotSubscribed ;
     QColor mTextColorMissing       ;
+
+    friend class const_iterator;
 };