/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * 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/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */
 
#include <svl/stylepool.hxx>
#include <svl/itemiter.hxx>
#include <svl/itempool.hxx>
#include <tools/debug.hxx>
#include <algorithm>
#include <map>
#include <memory>
#include <optional>
#include <vector>
 
namespace {
    /** A "Node" represents a subset of inserted SfxItemSets
     * The root node represents the empty set
     * The other nodes contain a SfxPoolItem and represents an item set which contains their
     * pool item and the pool items of their parents.
     */
    class Node
    {
        std::vector<std::unique_ptr<Node>> mChildren; // child nodes, create by findChildNode(..)
        // container of shared pointers of inserted item sets; for non-poolable
        // items more than one item set is needed
        std::vector< std::shared_ptr<SfxItemSet> > maItemSet;
        std::unique_ptr<const SfxPoolItem> mpItem;   // my pool item
        Node *mpUpper;               // if I'm a child node that's my parent node
        // #i86923#
        const bool mbIsItemIgnorable;
    public:
        // #i86923#
        Node() // root node Ctor
            : mpUpper( nullptr ),
              mbIsItemIgnorable( false )
        {}
        Node( const SfxPoolItem& rItem, Node* pParent, const bool bIgnorable ) // child node Ctor
            : mpItem( rItem.Clone() ),
              mpUpper( pParent ),
              mbIsItemIgnorable( bIgnorable )
        {}
        // #i86923#
        bool hasItemSet( const bool bCheckUsage ) const;
        // #i87808#
        std::shared_ptr<SfxItemSet> const & getItemSet() const
        {
            return maItemSet.back();
        }
        std::shared_ptr<SfxItemSet> const & getUsedOrLastAddedItemSet() const;
        void setItemSet( const SfxItemSet& rSet ){ maItemSet.push_back( std::shared_ptr<SfxItemSet>( rSet.Clone() ) ); }
        // #i86923#
        Node* findChildNode( const SfxPoolItem& rItem,
                             const bool bIsItemIgnorable );
        Node* nextItemSet( Node const * pLast,
                           const bool bSkipUnusedItemSet,
                           const bool bSkipIgnorable );
        // #i86923#
        bool hasIgnorableChildren( const bool bCheckUsage ) const;
        std::shared_ptr<SfxItemSet> getItemSetOfIgnorableChild(
                                        const bool bSkipUnusedItemSets ) const;
    };
 
    // #i87808#
    std::shared_ptr<SfxItemSet> const & Node::getUsedOrLastAddedItemSet() const
    {
        auto aIter = std::find_if(maItemSet.rbegin(), maItemSet.rend(),
            [](const std::shared_ptr<SfxItemSet>& rxItemSet) { return rxItemSet.use_count() > 1; });
 
        if (aIter != maItemSet.rend())
            return *aIter;
 
        return maItemSet.back();
    }
 
    // #i86923#
    bool Node::hasItemSet( const bool bCheckUsage ) const
    {
        bool bHasItemSet = false;
 
        if ( !maItemSet.empty())
        {
            if ( bCheckUsage )
            {
                bHasItemSet = std::any_of(maItemSet.rbegin(), maItemSet.rend(),
                    [](const std::shared_ptr<SfxItemSet>& rxItemSet) { return rxItemSet.use_count() > 1; });
            }
            else
            {
                bHasItemSet = true;
            }
        }
        return bHasItemSet;
    }
 
    // #i86923#
    Node* Node::findChildNode( const SfxPoolItem& rItem,
                               const bool bIsItemIgnorable )
    {
        for( auto const & rChild : mChildren )
        {
            if( rItem.Which() == rChild->mpItem->Which() &&
                rItem == *rChild->mpItem )
                return rChild.get();
        }
        // #i86923#
        auto pNextNode = new Node( rItem, this, bIsItemIgnorable );
        mChildren.emplace_back( pNextNode );
        return pNextNode;
    }
 
    /**
     * Find the next node which has a SfxItemSet.
     * The input parameter pLast has a sophisticated meaning:
     * downstairs only:
     * pLast == 0 => scan your children and their children
     *               but neither your parents neither your siblings
     * downstairs and upstairs:
     * pLast == this => scan your children, their children,
     *                  the children of your parent behind you, and so on
     * partial downstairs and upstairs
     *  pLast != 0 && pLast != this => scan your children behind the given children,
     *                 the children of your parent behind you and so on.
     *
     * OD 2008-03-11 #i86923#
     * introduce parameters <bSkipUnusedItemSets> and <bSkipIgnorable>
     * and its handling.
     */
    Node* Node::nextItemSet( Node const * pLast,
                             const bool bSkipUnusedItemSets,
                             const bool bSkipIgnorable )
    {
        // Searching downstairs
        auto aIter = mChildren.begin();
        // For pLast == 0 and pLast == this all children are of interest
        // for another pLast the search starts behind pLast...
        if( pLast && pLast != this )
        {
            aIter = std::find_if( mChildren.begin(), mChildren.end(),
                                  [&] (std::unique_ptr<Node> const &p) { return p.get() == pLast; });
            if( aIter != mChildren.end() )
                ++aIter;
        }
        Node *pNext = nullptr;
        while( aIter != mChildren.end() )
        {
            // #i86923#
            if ( bSkipIgnorable && (*aIter)->mbIsItemIgnorable )
            {
                ++aIter;
                continue;
            }
            pNext = aIter->get();
            // #i86923#
            if ( pNext->hasItemSet( bSkipUnusedItemSets ) )
            {
                return pNext;
            }
            if ( bSkipIgnorable &&
                 pNext->hasIgnorableChildren( bSkipUnusedItemSets ) )
            {
                return pNext;
            }
            pNext = pNext->nextItemSet( nullptr, bSkipUnusedItemSets, bSkipIgnorable ); // 0 => downstairs only
            if( pNext )
                return pNext;
            ++aIter;
        }
        // Searching upstairs
        if( pLast && mpUpper )
        {
            // #i86923#
            pNext = mpUpper->nextItemSet( this, bSkipUnusedItemSets, bSkipIgnorable );
        }
        return pNext;
    }
 
    // #i86923#
    bool Node::hasIgnorableChildren( const bool bCheckUsage ) const
    {
        return std::any_of(mChildren.begin(), mChildren.end(),
            [&bCheckUsage](const std::unique_ptr<Node>& rxChild) {
                Node* pChild = rxChild.get();
                return pChild->mbIsItemIgnorable &&
                    (!bCheckUsage ||
                     ( pChild->hasItemSet( bCheckUsage /* == true */ ) ||
                       pChild->hasIgnorableChildren( bCheckUsage /* == true */ ) ));
            });
    }
 
    std::shared_ptr<SfxItemSet> Node::getItemSetOfIgnorableChild(
                                        const bool bSkipUnusedItemSets ) const
    {
        DBG_ASSERT( hasIgnorableChildren( bSkipUnusedItemSets ),
                    "<Node::getItemSetOfIgnorableChild> - node has no ignorable children" );
 
        for( const auto& rxChild : mChildren )
        {
            Node* pChild = rxChild.get();
            if ( pChild->mbIsItemIgnorable )
            {
                if ( pChild->hasItemSet( bSkipUnusedItemSets ) )
                {
                    return pChild->getUsedOrLastAddedItemSet();
                }
                else
                {
                    pChild = pChild->nextItemSet( nullptr, bSkipUnusedItemSets, false );
                    if ( pChild )
                    {
                        return pChild->getUsedOrLastAddedItemSet();
                    }
                }
            }
        }
 
        std::shared_ptr<SfxItemSet> pReturn;
        return pReturn;
    }
 
    class Iterator
    {
        std::map< const SfxItemSet*, Node >& mrRoot;
        std::map< const SfxItemSet*, Node >::iterator mpCurrNode;
        Node* mpNode;
        const bool mbSkipUnusedItemSets;
        const bool mbSkipIgnorable;
        /// List of item set parents, ordered by their name.
        std::vector<const SfxItemSet*> maParents;
        /// The iterator's current position.
        std::vector<const SfxItemSet*>::iterator mpCurrParent;
    public:
        // #i86923#
        Iterator( std::map< const SfxItemSet*, Node >& rR,
                  const bool bSkipUnusedItemSets,
                  const bool bSkipIgnorable,
                  const std::map< const SfxItemSet*, OUString>& rParentNames )
            : mrRoot( rR ),
              mpNode(nullptr),
              mbSkipUnusedItemSets( bSkipUnusedItemSets ),
              mbSkipIgnorable( bSkipIgnorable )
        {
            // Collect the parent pointers into a vector we can sort.
            for (const auto& rParent : mrRoot)
                maParents.push_back(rParent.first);
 
            // Sort the parents using their name, if they have one.
            if (!rParentNames.empty())
            {
                std::stable_sort(maParents.begin(), maParents.end(),
                          [&rParentNames](const SfxItemSet* pA, const SfxItemSet* pB) {
                              OUString aA;
                              OUString aB;
                              auto it = rParentNames.find(pA);
                              if (it != rParentNames.end())
                                  aA = it->second;
                              it = rParentNames.find(pB);
                              if (it != rParentNames.end())
                                  aB = it->second;
                              return aA < aB;
                          });
            }
 
            // Start the iteration.
            mpCurrParent = maParents.begin();
            if (mpCurrParent != maParents.end())
                mpCurrNode = mrRoot.find(*mpCurrParent);
        }
        std::shared_ptr<SfxItemSet> getNext();
    };
 
    std::shared_ptr<SfxItemSet> Iterator::getNext()
    {
        std::shared_ptr<SfxItemSet> pReturn;
        while( mpNode || mpCurrParent != maParents.end() )
        {
            if( !mpNode )
            {
                mpNode = &mpCurrNode->second;
                // Perform the actual increment.
                ++mpCurrParent;
                if (mpCurrParent != maParents.end())
                    mpCurrNode = mrRoot.find(*mpCurrParent);
                // #i86923#
                if ( mpNode->hasItemSet( mbSkipUnusedItemSets ) )
                {
                    // #i87808#
                    return mpNode->getUsedOrLastAddedItemSet();
                }
            }
            // #i86923#
            mpNode = mpNode->nextItemSet( mpNode, mbSkipUnusedItemSets, mbSkipIgnorable );
            if ( mpNode && mpNode->hasItemSet( mbSkipUnusedItemSets ) )
            {
                // #i87808#
                return mpNode->getUsedOrLastAddedItemSet();
            }
            if ( mbSkipIgnorable &&
                 mpNode && mpNode->hasIgnorableChildren( mbSkipUnusedItemSets ) )
            {
                return mpNode->getItemSetOfIgnorableChild( mbSkipUnusedItemSets );
            }
        }
        return pReturn;
    }
 
}
 
/**
 * This static method creates a unique name from a shared pointer to a SfxItemSet
 * The name is the memory address of the SfxItemSet itself.
 */
OUString StylePool::nameOf( const std::shared_ptr<SfxItemSet>& pSet )
{
    return OUString::number( reinterpret_cast<sal_IntPtr>( pSet.get() ), 16 );
}
 
/**
 * class StylePoolImpl organized a tree-structure where every node represents a SfxItemSet.
 * The insertItemSet method adds a SfxItemSet into the tree if necessary and returns a shared_ptr
 * to a copy of the SfxItemSet.
 * The aRoot-Node represents an empty SfxItemSet.
 */
class StylePoolImpl
{
private:
    std::map< const SfxItemSet*, Node > maRoot;
    /// Names of maRoot keys.
    std::map< const SfxItemSet*, OUString> maParentNames;
    // #i86923#
    std::unique_ptr<SfxItemSet> mpIgnorableItems;
#if OSL_DEBUG_LEVEL >= 2
    sal_Int32 mnCount;
#endif
public:
    // #i86923#
    explicit StylePoolImpl( SfxItemSet const * pIgnorableItems )
        :
#if OSL_DEBUG_LEVEL >= 2
          mnCount(0),
#endif
          mpIgnorableItems( pIgnorableItems != nullptr
                            ? pIgnorableItems->Clone( false )
                            : nullptr )
    {
        DBG_ASSERT( !pIgnorableItems || !pIgnorableItems->Count(),
                    "<StylePoolImpl::StylePoolImpl(..)> - misusage: item set for ignorable item should be empty. Please correct usage." );
        DBG_ASSERT( !mpIgnorableItems || !mpIgnorableItems->Count(),
                    "<StylePoolImpl::StylePoolImpl(..)> - <SfxItemSet::Clone( sal_False )> does not work as expected - <mpIgnorableItems> is not empty." );
    }
 
    std::shared_ptr<SfxItemSet> insertItemSet( const SfxItemSet& rSet, const OUString* pParentName = nullptr );
 
    // #i86923#
    Iterator createIterator( bool bSkipUnusedItemSets, bool bSkipIgnorableItems );
};
 
 
std::shared_ptr<SfxItemSet> StylePoolImpl::insertItemSet( const SfxItemSet& rSet, const OUString* pParentName )
{
    bool bNonShareable(false);
    Node* pCurNode = &maRoot[ rSet.GetParent() ];
    if (pParentName)
        maParentNames[ rSet.GetParent() ] = *pParentName;
    SfxItemIter aIter( rSet );
    const SfxPoolItem* pItem = aIter.GetCurItem();
    // Every SfxPoolItem in the SfxItemSet causes a step deeper into the tree,
    // a complete empty SfxItemSet would stay at the root node.
    // #i86923# insert ignorable items to the tree leaves.
    std::optional<SfxItemSet> xFoundIgnorableItems;
    if ( mpIgnorableItems )
    {
        xFoundIgnorableItems.emplace( *mpIgnorableItems );
    }
    while( pItem )
    {
        if (!pItem->isShareable())
            bNonShareable = true;
        if (!xFoundIgnorableItems || (xFoundIgnorableItems->Put(*pItem) == nullptr))
        {
            pCurNode = pCurNode->findChildNode( *pItem, false );
        }
        pItem = aIter.NextItem();
    }
    if ( xFoundIgnorableItems && xFoundIgnorableItems->Count() > 0 )
    {
        SfxItemIter aIgnorableItemsIter( *xFoundIgnorableItems );
        pItem = aIgnorableItemsIter.GetCurItem();
        while( pItem )
        {
            if (!pItem->isShareable())
                bNonShareable = true;
            pCurNode = pCurNode->findChildNode( *pItem, true );
            pItem = aIgnorableItemsIter.NextItem();
        }
    }
    // Every leaf node represents an inserted item set, but "non-leaf" nodes represents subsets
    // of inserted itemsets.
    // These nodes could have but does not need to have a shared_ptr to an item set.
    if( !pCurNode->hasItemSet( false ) )
    {
        pCurNode->setItemSet( rSet );
        bNonShareable = false; // to avoid a double insertion
#if OSL_DEBUG_LEVEL >= 2
        ++mnCount;
#endif
    }
    // If rSet contains at least one non poolable item, a new itemset has to be inserted
    if( bNonShareable )
        pCurNode->setItemSet( rSet );
#if OSL_DEBUG_LEVEL >= 2
    {
        sal_Int32 nCheck = -1;
        Iterator aIter = createIterator(false,false);
        std::shared_ptr<SfxItemSet> pTemp;
        do
        {
            ++nCheck;
            pTemp = aIter.getNext();
        } while( pTemp.get() );
        DBG_ASSERT( mnCount == nCheck, "Wrong counting");
    }
#endif
    return pCurNode->getItemSet();
}
 
// #i86923#
Iterator StylePoolImpl::createIterator( bool bSkipUnusedItemSets,
                                                         bool bSkipIgnorableItems )
{
    return Iterator( maRoot, bSkipUnusedItemSets, bSkipIgnorableItems, maParentNames );
}
// Ctor, Dtor and redirected methods of class StylePool, nearly inline ;-)
 
// #i86923#
StylePool::StylePool( SfxItemSet const * pIgnorableItems )
    : pImpl( new StylePoolImpl( pIgnorableItems ) )
{}
 
std::shared_ptr<SfxItemSet> StylePool::insertItemSet( const SfxItemSet& rSet, const OUString* pParentName )
{ return pImpl->insertItemSet( rSet, pParentName ); }
 
void StylePool::populateCacheMap(std::unordered_map< OUString, std::shared_ptr<SfxItemSet> >& rCacheMap)
{
    Iterator aIter = pImpl->createIterator(/*bSkipUnusedItemSets*/false, /*bSkipIgnorableItems*/false);
    std::shared_ptr<SfxItemSet> pStyle = aIter.getNext();
    while( pStyle )
    {
        OUString aName( StylePool::nameOf(pStyle) );
        rCacheMap[ aName ] = pStyle;
        pStyle = aIter.getNext();
    }
}
 
void StylePool::getAllStyles( std::vector<std::shared_ptr<SfxItemSet>> &rStyles )
{
    // setup <StylePool> iterator, which skips unused styles and ignorable items
    Iterator aIter = pImpl->createIterator( true, true );
    std::shared_ptr<SfxItemSet> pStyle = aIter.getNext();
    while( pStyle )
    {
        rStyles.push_back( pStyle );
        pStyle = aIter.getNext();
    }
}
 
 
StylePool::~StylePool()
{}
 
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */

V614 The 'pReturn' smart pointer is utilized immediately after being declared or reset. It is suspicious that no value was assigned to it.

V614 The 'pReturn' smart pointer is utilized immediately after being declared or reset. It is suspicious that no value was assigned to it.