/* -*- 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 .
 */

#ifndef INCLUDED_COMPHELPER_SEQUENCE_HXX
#define INCLUDED_COMPHELPER_SEQUENCE_HXX

#include <com/sun/star/uno/Sequence.hxx>
#include <osl/diagnose.h>
#include <comphelper/comphelperdllapi.h>

#include <vector>

namespace comphelper
{
    /** Search the given string within the given sequence, return the position of the first occurrence.
        Returns -1 if nothing found.
    */
    COMPHELPER_DLLPUBLIC sal_Int32 findValue(const css::uno::Sequence< OUString >& _rList, const OUString& _rValue);

    namespace internal
    {
        template <class T>
        inline void implCopySequence(const T* _pSource, T*& _pDest, sal_Int32 _nSourceLen)
        {
            for (sal_Int32 i=0; i<_nSourceLen; ++i, ++_pSource, ++_pDest)
                *_pDest = *_pSource;
        }
    }

    /// concat two sequences
    template <class T>
    inline css::uno::Sequence<T> concatSequences(const css::uno::Sequence<T>& _rLeft, const css::uno::Sequence<T>& _rRight)
    {
        sal_Int32 nLeft(_rLeft.getLength()), nRight(_rRight.getLength());
        const T* pLeft = _rLeft.getConstArray();
        const T* pRight = _rRight.getConstArray();

        sal_Int32 nReturnLen(nLeft + nRight);
        css::uno::Sequence<T> aReturn(nReturnLen);
        T* pReturn = aReturn.getArray();

        internal::implCopySequence(pLeft, pReturn, nLeft);
        internal::implCopySequence(pRight, pReturn, nRight);

        return aReturn;
    }

    /// concat additional elements from right sequence to left sequence
    ///
    /// be aware that this takes time O(|left| * |right|)
    template<typename T> inline css::uno::Sequence<T> combineSequences(
        css::uno::Sequence<T> const & left, css::uno::Sequence<T> const & right)
    {
        sal_Int32 n1 = left.getLength();
        css::uno::Sequence<T> ret(n1 + right.getLength());
            //TODO: check for overflow
        T * p = ret.getArray();
        internal::implCopySequence(left.getConstArray(), p, n1);
        sal_Int32 n2 = n1;
        for (sal_Int32 i = 0; i != right.getLength(); ++i) {
            bool found = false;
            for (sal_Int32 j = 0; j != n1; ++j) {
                if (right[i] == left[j]) {
                    found = true;
                    break;
                }
            }
            if (!found) {
                ret[n2++] = right[i];
            }
        }
        ret.realloc(n2);
        return ret;
    }

    /// concat three sequences
    template <class T>
    inline css::uno::Sequence<T> concatSequences(const css::uno::Sequence<T>& _rLeft, const css::uno::Sequence<T>& _rMiddle, const css::uno::Sequence<T>& _rRight)
    {
        sal_Int32 nLeft(_rLeft.getLength()), nMiddle(_rMiddle.getLength()), nRight(_rRight.getLength());
        const T* pLeft = _rLeft.getConstArray();
        const T* pMiddle = _rMiddle.getConstArray();
        const T* pRight = _rRight.getConstArray();

        sal_Int32 nReturnLen(nLeft + nMiddle + nRight);
        css::uno::Sequence<T> aReturn(nReturnLen);
        T* pReturn = aReturn.getArray();

        internal::implCopySequence(pLeft, pReturn, nLeft);
        internal::implCopySequence(pMiddle, pReturn, nMiddle);
        internal::implCopySequence(pRight, pReturn, nRight);

        return aReturn;
    }


    /// remove a specified element from a sequences
    template<class T>
    inline void removeElementAt(css::uno::Sequence<T>& _rSeq, sal_Int32 _nPos)
    {
        sal_Int32 nLength = _rSeq.getLength();

        OSL_ENSURE(0 <= _nPos && _nPos < nLength, "invalid index");

        for (sal_Int32 i = _nPos + 1; i < nLength; ++i)
        {
            _rSeq[i-1] = _rSeq[i];
        }

        _rSeq.realloc(nLength-1);
    }


    //= iterating through sequences

    /** a helper class for iterating through a sequence
    */
    template <class TYPE>
    class OSequenceIterator
    {
        const TYPE* m_pElements;
        sal_Int32   m_nLen;
        const TYPE* m_pCurrent;

    public:
        /** construct a sequence iterator from a sequence
        */
        OSequenceIterator(const css::uno::Sequence< TYPE >& _rSeq);
        /** construct a sequence iterator from a Any containing a sequence
        */
        OSequenceIterator(const css::uno::Any& _rSequenceAny);

        bool hasMoreElements() const;
        css::uno::Any  nextElement();

    private:
        inline void construct(const css::uno::Sequence< TYPE >& _rSeq);
    };


    template <class TYPE>
    inline OSequenceIterator<TYPE>::OSequenceIterator(const css::uno::Sequence< TYPE >& _rSeq)
        :m_pElements(nullptr)
        ,m_nLen(0)
        ,m_pCurrent(nullptr)
    {
        construct(_rSeq);
    }


    template <class TYPE>
    inline OSequenceIterator<TYPE>::OSequenceIterator(const css::uno::Any& _rSequenceAny)
        :m_pElements(nullptr)
        ,m_nLen(0)
        ,m_pCurrent(nullptr)
    {
        css::uno::Sequence< TYPE > aContainer;
        bool bSuccess = _rSequenceAny >>= aContainer;
        OSL_ENSURE(bSuccess, "OSequenceIterator::OSequenceIterator: invalid Any!");
        construct(aContainer);
    }


    template <class TYPE>
    void OSequenceIterator<TYPE>::construct(const css::uno::Sequence< TYPE >& _rSeq)
    {
        m_pElements = _rSeq.getConstArray();
        m_nLen = _rSeq.getLength();
        m_pCurrent = m_pElements;
    }


    template <class TYPE>
    inline bool OSequenceIterator<TYPE>::hasMoreElements() const
    {
        return m_pCurrent - m_pElements < m_nLen;
    }


    template <class TYPE>
    inline css::uno::Any OSequenceIterator<TYPE>::nextElement()
    {
        return css::uno::toAny(*m_pCurrent++);
    }

    /** Copy from a plain C/C++ array into a Sequence.

        @tpl SrcType
        Array element type. Must be assignable to DstType

        @tpl DstType
        Sequence element type. Must be assignable from SrcType

        @param i_pArray
        Valid pointer to at least num elements of type SrcType

        @param nNum
        Number of array elements to copy

        @return the resulting Sequence

        @attention when copying from e.g. a double array to a
        Sequence<int>, no proper rounding will be performed, but the
        values will be truncated. There's currently no measure to
        prevent or detect precision loss, overflow or truncation.
     */
    template < typename DstType, typename SrcType >
    inline css::uno::Sequence< DstType > arrayToSequence( const SrcType* i_pArray, sal_Int32 nNum )
    {
        css::uno::Sequence< DstType > result( nNum );
        ::std::copy( i_pArray, i_pArray+nNum, result.getArray() );
        return result;
    }


    /** Copy from a Sequence into a plain C/C++ array

        @tpl SrcType
        Sequence element type. Must be assignable to DstType

        @tpl DstType
        Array element type. Must be assignable from SrcType

        @param io_pArray
        Valid pointer to at least i_Sequence.getLength() elements of
        type DstType

        @param i_Sequence
        Reference to a Sequence of SrcType elements

        @return a pointer to the array

        @attention when copying from e.g. a Sequence<double> to an int
        array, no proper rounding will be performed, but the values
        will be truncated. There's currently no measure to prevent or
        detect precision loss, overflow or truncation.
     */
    template < typename DstType, typename SrcType >
    inline DstType* sequenceToArray( DstType* io_pArray, const css::uno::Sequence< SrcType >& i_Sequence )
    {
        ::std::copy( i_Sequence.begin(), i_Sequence.end(), io_pArray );
        return io_pArray;
    }


    /** Copy from a container into a Sequence

        @tpl SrcType
        Container type. This type must fulfill the STL container
        concept, in particular, the size(), begin() and end() methods
        must be available and have the usual semantics.

        @tpl DstType
        Sequence element type. Must be assignable from SrcType's
        elements

        @param i_Container
        Reference to the input contain with elements of type SrcType

        @return the generated Sequence

        @attention this function always performs a copy. Furthermore,
        when copying from e.g. a vector<double> to a Sequence<int>, no
        proper rounding will be performed, but the values will be
        truncated. There's currently no measure to prevent or detect
        precision loss, overflow or truncation.
     */
    template < typename DstElementType, typename SrcType >
    inline css::uno::Sequence< DstElementType > containerToSequence( const SrcType& i_Container )
    {
        css::uno::Sequence< DstElementType > result( i_Container.size() );
        ::std::copy( i_Container.begin(), i_Container.end(), result.getArray() );
        return result;
    }

    // this one does better type deduction, but does not allow us to copy into a different element type
    template < typename SrcType >
    inline css::uno::Sequence< typename SrcType::value_type > containerToSequence( const SrcType& i_Container )
    {
        css::uno::Sequence< typename SrcType::value_type > result( i_Container.size() );
        ::std::copy( i_Container.begin(), i_Container.end(), result.getArray() );
        return result;
    }

    // handle arrays
    template<typename ElementType, std::size_t SrcSize>
    inline css::uno::Sequence< ElementType > containerToSequence( ElementType const (&i_Array)[ SrcSize ] )
    {
        return css::uno::Sequence< ElementType >( i_Array, SrcSize );
    }

    template <typename T>
    inline css::uno::Sequence<T> containerToSequence(
        ::std::vector<T> const& v )
    {
        return css::uno::Sequence<T>(
            v.data(), static_cast<sal_Int32>(v.size()) );
    }


    /** Copy from a Sequence into a container

        @tpl SrcType
        Sequence element type. Must be assignable to SrcType's
        elements

        @tpl DstType
        Container type. This type must fulfill the STL container and
        sequence concepts, in particular, the begin(), end() and the
        unary constructor DstType(int) methods must be available and
        have the usual semantics.

        @param i_Sequence
        Reference to a Sequence of SrcType elements

        @return the generated container

        @attention this function always performs a copy. Furthermore,
        when copying from e.g. a Sequence<double> to a vector<int>, no
        proper rounding will be performed, but the values will be
        truncated. There's currently no measure to prevent or detect
        precision loss, overflow or truncation.
     */
    template < typename DstType, typename SrcType >
    inline DstType sequenceToContainer( const css::uno::Sequence< SrcType >& i_Sequence )
    {
        DstType result( i_Sequence.getLength() );
        ::std::copy( i_Sequence.begin(), i_Sequence.end(), result.begin() );
        return result;
    }

    // this one does better type deduction, but does not allow us to copy into a different element type
    template < typename DstType >
    inline DstType sequenceToContainer( const css::uno::Sequence< typename DstType::value_type >& i_Sequence )
    {
        DstType result( i_Sequence.getLength() );
        ::std::copy( i_Sequence.begin(), i_Sequence.end(), result.begin() );
        return result;
    }

    /** Copy from a Sequence into an existing container

        This potentially saves a needless extra copy operation over
        the whole container, as it passes the target object by
        reference.

        @tpl SrcType
        Sequence element type. Must be assignable to SrcType's
        elements

        @tpl DstType
        Container type. This type must fulfill the STL container and
        sequence concepts, in particular, the begin(), end() and
        resize(int) methods must be available and have the usual
        semantics.

        @param o_Output
        Reference to the target container

        @param i_Sequence
        Reference to a Sequence of SrcType elements

        @return a non-const reference to the given container

        @attention this function always performs a copy. Furthermore,
        when copying from e.g. a Sequence<double> to a vector<int>, no
        proper rounding will be performed, but the values will be
        truncated. There's currently no measure to prevent or detect
        precision loss, overflow or truncation.
     */
    template < typename DstType, typename SrcType >
    inline DstType& sequenceToContainer( DstType& o_Output, const css::uno::Sequence< SrcType >& i_Sequence )
    {
        o_Output.resize( i_Sequence.getLength() );
        ::std::copy( i_Sequence.begin(), i_Sequence.end(), o_Output.begin() );
        return o_Output;
    }

    /** Copy (keys or values) from a associate container into a Sequence

        @tpl M map container type eg. std::map/std::unordered_map

        @return the generated Sequence
     */
    template < typename M >
    inline css::uno::Sequence< typename M::key_type > mapKeysToSequence( M const& map )
    {
        css::uno::Sequence< typename M::key_type > ret( static_cast<sal_Int32>(map.size()) );
        typename M::key_type* pArray = ret.getArray();
        for (const auto& i : map)
            *pArray++ = i.first;
        return ret;
    }

    template < typename M >
    inline css::uno::Sequence< typename M::mapped_type > mapValuesToSequence( M const& map )
    {
        css::uno::Sequence< typename M::mapped_type > ret( static_cast<sal_Int32>(map.size()) );
        typename M::mapped_type* pArray = ret.getArray();
        for (const auto& i : map)
            *pArray++ = i.second;
        return ret;
    }

}   // namespace comphelper


#endif // INCLUDED_COMPHELPER_SEQUENCE_HXX

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */