/*	Copyright (C) 2004 Garrett A. Kajmowicz
	This file is part of the uClibc++ Library.
	This library is free software; you can redistribute it and/or
	modify it under the terms of the GNU Lesser General Public
	License as published by the Free Software Foundation; either
	version 2.1 of the License, or (at your option) any later version.

	This library is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
	Lesser General Public License for more details.
	
	You should have received a copy of the GNU Lesser General Public
	License along with this library; if not, write to the Free Software
	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

*/


#include <memory>
#include <iterator>
#include <stdexcept>

#ifndef __STD_HEADER_DEQUE
#define __STD_HEADER_DEQUE


namespace std{
	template <class T, class Allocator = allocator<T> > class deque;
	template <class T, class Allocator> bool operator==(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator< (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator!=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator> (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator>=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator<=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> void swap(deque<T,Allocator>& x, deque<T,Allocator>& y);

	template <class T, class Allocator> class _UCXXEXPORT deque {
	public:
		friend bool operator==<>(const deque<T, Allocator>& x, const deque<T, Allocator>& y);
		friend class deque_iter;
		friend class deque_citer;
		class deque_iter;
		class deque_citer;

		typedef typename Allocator::reference		reference;
		typedef typename Allocator::const_reference	const_reference;
		typedef deque_iter				iterator;
		typedef deque_citer				const_iterator;
		typedef typename Allocator::size_type		size_type;
		typedef typename Allocator::difference_type	difference_type;
		typedef T					value_type;
		typedef Allocator				allocator_type;
		typedef typename Allocator::pointer		pointer;
		typedef typename Allocator::const_pointer	const_pointer;
		typedef std::reverse_iterator<iterator>		reverse_iterator;
		typedef std::reverse_iterator<const_iterator>	const_reverse_iterator;

		explicit deque(const Allocator& al = Allocator());
		explicit deque(size_type n, const T& value = T(), const Allocator& al = Allocator());
		template <class InputIterator> deque(InputIterator first, InputIterator last, const Allocator& = Allocator());
		deque(const deque<T,Allocator>& x);
		~deque();

		deque<T,Allocator>& operator=(const deque<T,Allocator>& x);
		template <class InputIterator> void assign(InputIterator first, InputIterator last);
		template <class Size, class U> void assign(Size n, const U& u = U());
		allocator_type get_allocator() const;

		iterator		begin();
		const_iterator		begin() const;
		iterator		end();
		const_iterator		end() const;
		reverse_iterator	rbegin();
		const_reverse_iterator	rbegin() const;
		reverse_iterator	rend();
		const_reverse_iterator	rend() const;

		size_type		size() const;
		size_type		max_size() const;
		void			resize(size_type sz, T c = T());
		bool			empty() const;

		reference	operator[](size_type n);
		const_reference	operator[](size_type n) const;
		reference	at(size_type n);
		const_reference	at(size_type n) const;
		reference	front();
		const_reference	front() const;
		reference	back();
		const_reference	back() const;

		void push_front(const T& x);
		void push_back(const T& x);
		iterator insert(iterator position, const T& x = T());
		void     insert(iterator position, size_type n, const T& x);
		template <class InputIterator> void insert (iterator position, InputIterator first, InputIterator last);
		void pop_front();
		void pop_back();

		iterator erase(iterator position);
		iterator erase(iterator first, iterator last);
		void     swap(deque<T,Allocator>&);
		void     clear();

	protected:
		void reserve(size_type n);
		inline size_type array_element(size_type deque_element) const{
			if(deque_element < (data_size - first_element)){
				return first_element + deque_element;
			}
			return deque_element - (data_size - first_element);
		}
		inline size_type first_subtract(size_type sub_size) const{
			if(sub_size > first_element){
				return (data_size - first_element) - sub_size;
			}
			return first_element - sub_size;
		}

		T * data;
		size_type data_size;		//Physical size of array
		size_type elements;		//Elements in array
		size_type first_element;	//Element number of array 0..n
		size_type last_element;		//Element number of array 0..n
		Allocator a;

	};


	template<class T, class Allocator> class _UCXXEXPORT deque<T, Allocator>::deque_iter
		: public std::iterator<
			random_access_iterator_tag,
			T,
			typename Allocator::difference_type,
			typename Allocator::pointer,
			typename Allocator::reference
		>
	{
	friend class deque<T, Allocator>;
	protected:
		deque<T, Allocator> * container;
		typename Allocator::size_type element;

	public:
		deque_iter() : container(0), element(0) {  }
		deque_iter(const deque_iter & d) : container (d.container), element(d.element) {  }
		deque_iter(deque<T, Allocator> * c, typename Allocator::size_type e)
			: container(c), element(e)
		{
			return;
		}
		~deque_iter() {  }
		deque_iter & operator=(const deque_iter & d){
			container = d.container;
			element = d.element;
			return *this;
		}
		T & operator*(){
			return container->data[container->array_element(element)];
		}
		T * operator->(){
			return container->data + container->array_element(element);
		}
		const T & operator*() const{
			return container->data[container->array_element(element)];
		}
		const T * operator->() const{
			return container->data + container->array_element(element);
		}
		bool operator==(const deque_iter & d) const{
			if(container == d.container && element == d.element){
				return true;
			}
			return false;
		}
		bool operator!=(const deque_iter & d) const{
			if(container != d.container || element  != d.element){
				return true;
			}
			return false;
		}
		bool operator<(const deque_iter & d) const{
			if(element < d.element){
				return true;
			}
			return false;
		}
		bool operator<=(const deque_iter & d) const{
			if(element <= d.element){
				return true;
			}
			return false;
		}
		bool operator>(const deque_iter & d) const{
			if(element > d.element){
				return true;
			}
			return false;
		}
		bool operator>=(const deque_iter & d) const{
			if(element >= d.element){
				return true;
			}
			return false;
		}
		deque_iter & operator++(){
			++element;
			return *this;
		}
		deque_iter operator++(int){
			deque_iter temp(container, element);
			++element;
			return temp;
		}
		deque_iter operator+(typename Allocator::size_type n){
			deque_iter temp(container, element + n);
			return temp;
		}
		deque_iter & operator+=(typename Allocator::size_type n){
			element += n;
			return *this;
		}
		deque_iter & operator--(){
			--element;
			return *this;
		}
		deque_iter operator--(int){
			deque_iter temp(container, element);
			--element;
			return temp;
		}
		deque_iter operator-(typename Allocator::size_type n){
			deque_iter temp(container, element - n);
			return temp;
		}
		deque_iter & operator-=(typename Allocator::size_type n){
			element -= n;
			return *this;
		}
		typename Allocator::size_type operator-(const deque_iter & d){
			return element - d.element;
		}

	};

	template<class T, class Allocator> class _UCXXEXPORT deque<T, Allocator>::deque_citer
		: public std::iterator<
			random_access_iterator_tag,
			T,
			typename Allocator::difference_type,
			typename Allocator::const_pointer,
			typename Allocator::const_reference
		>
	{
	friend class deque<T, Allocator>;
	protected:
		const deque<T, Allocator> * container;
		typename Allocator::size_type element;

	public:
		deque_citer() : container(0), element(0) {  }
		deque_citer(const deque_citer & d) : container (d.container), element(d.element) {  }
		deque_citer(const deque<T, Allocator> * c, typename Allocator::size_type e)
			: container(c), element(e)
		{
			return;
		}
		~deque_citer() {  }
		deque_citer & operator=(const deque_iter & d){
			container = d.container;
			element = d.element;
			return *this;
		}
		const T & operator*() const{
			return container->data[container->array_element(element)];
		}
		const T * operator->() const{
			return container->data + container->array_element(element);
		}
		bool operator==(const deque_citer & d) const{
			if(container == d.container && element == d.element){
				return true;
			}
			return false;
		}
		bool operator!=(const deque_citer & d) const{
			if(container != d.container || element  != d.element){
				return true;
			}
			return false;
		}
		bool operator<(const deque_citer & d) const{
			if(element < d.element){
				return true;
			}
			return false;
		}
		bool operator<=(const deque_citer & d) const{
			if(element <= d.element){
				return true;
			}
			return false;
		}
		bool operator>(const deque_citer & d) const{
			if(element > d.element){
				return true;
			}
			return false;
		}
		bool operator>=(const deque_citer & d){
			if(element >= d.element){
				return true;
			}
			return false;
		}
		deque_citer & operator++(){
			++element;
			return *this;
		}
		deque_citer operator++(int){
			deque_citer temp(container, element);
			++element;
			return temp;
		}
		deque_citer operator+(typename Allocator::size_type n){
			deque_citer temp(container, element + n);
			return temp;
		}
		deque_citer & operator+=(typename Allocator::size_type n){
			element += n;
			return *this;
		}
		deque_citer & operator--(){
			--element;
			return *this;
		}
		deque_citer operator--(int){
			deque_citer temp(container, element);
			--element;
			return temp;
		}
		deque_citer operator-(typename Allocator::size_type n){
			deque_citer temp(container, element - n);
			return temp;
		}
		deque_citer & operator-=(typename Allocator::size_type n){
			element -= n;
			return *this;
		}
		typename Allocator::size_type operator-(const deque_citer & d){
			return element - d.element;
		}

	};

	template<class T, class Allocator> deque<T, Allocator>::deque(const Allocator& al)
		: data(0), 
		data_size(0), elements(0), first_element(0), last_element(0), a(al)
	{
		data_size = __UCLIBCXX_STL_BUFFER_SIZE__;
		data = a.allocate(data_size);
		first_element = data_size /2;
		last_element = first_element;
	}


	template<class T, class Allocator> deque<T, Allocator>::deque(
		size_type n, const T& value, const Allocator& al)
		: data(0),
		elements(n), first_element(0), last_element(0), a(al)
	{
		data_size = elements + __UCLIBCXX_STL_BUFFER_SIZE__;
		data = a.allocate(data_size);
		first_element = (data_size - elements) / 2;
		last_element = first_element;

		for(n=first_element ; n < last_element; ++n ){
			a.construct(data+n, value);
		}
	}


	template<class T, class Allocator> template <class InputIterator> 
		deque<T, Allocator>::deque(InputIterator first, InputIterator last, const Allocator& al)
		: data(0),
		data_size(0), elements(0), first_element(0), last_element(0), a(al)
	{
		data_size = __UCLIBCXX_STL_BUFFER_SIZE__;
		data = a.allocate(data_size);
		first_element = data_size / 4;	//Note sure how big, but let's add a little space...
		last_element = first_element;
		while(first != last){
			push_back(*first);
			++first;
		}
	}


	template<class T, class Allocator> deque<T, Allocator>::deque(const deque<T,Allocator>& x)
		: data(0),
		elements(0), first_element(0), last_element(0), a(x.a)
	{
		data_size = x.elements + __UCLIBCXX_STL_BUFFER_SIZE__;
		data = a.allocate(data_size);
		first_element = (data_size - x.elements) / 2;
		last_element = first_element;
		for(size_type i=0; i < x.elements; ++i){
			push_back(x[i]);
		}
	}


	template<class T, class Allocator> deque<T, Allocator>::~deque(){
		clear();
		a.deallocate(data, data_size);
	}

	template<class T, class Allocator> deque<T,Allocator>& deque<T, Allocator>::
		operator=(const deque<T,Allocator>& x)
	{
		if(&x == this){
			return *this;
		}
		resize(x.elements);
		for(size_t i = 0; i < elements; ++i){
			data[array_element(i)] = x[i];
		}
		return *this;
	}


	template<class T, class Allocator> template <class InputIterator> void
		deque<T, Allocator>::assign(InputIterator first, InputIterator last)
	{
		clear();
		while(first !=last){
			push_back(*first);
			++first;
		}
	}


	template<class T, class Allocator> template <class Size, class U> void
		deque<T, Allocator>::assign(Size n, const U& u)
	{
		if(&u == this){
			return;
		}
		clear();
		for(size_type i = 0; i < n; ++i){
			push_back(u);
		}
	}


	template<class T, class Allocator> typename deque<T, Allocator>::allocator_type 
		deque<T, Allocator>::get_allocator() const
	{
		return a;
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::iterator deque<T, Allocator>::begin()
	{
		return deque_iter(this, 0);
	}


	template<class T, class Allocator> typename deque<T, Allocator>::const_iterator
		deque<T, Allocator>::begin() const
	{
		return deque_citer(this, 0);
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::iterator deque<T, Allocator>::end()
	{
		return deque_iter(this, elements);
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_iterator deque<T, Allocator>::end() const
	{
		return deque_citer(this, elements);
	}
	
	template<class T, class Allocator> typename
		deque<T, Allocator>::reverse_iterator deque<T, Allocator>::rbegin()
	{
		return reverse_iterator(end());
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reverse_iterator deque<T, Allocator>::rbegin() const
	{
		return const_reverse_iterator(end());
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::reverse_iterator deque<T, Allocator>::rend()
	{
		return reverse_iterator(begin());
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reverse_iterator deque<T, Allocator>::rend() const
	{
		return const_reverse_iterator(begin());
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::size_type deque<T, Allocator>::size() const
	{
		return elements;
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::size_type deque<T, Allocator>::max_size() const
	{
		return ((size_type)(-1)) / sizeof(T);
	}

	template<class T, class Allocator> void deque<T, Allocator>::resize(size_type sz, T c){
		reserve(sz);
		while(sz > size()){
			push_back(c);
		}
		while(sz < size()){
			pop_back();
		}
	}

	template<class T, class Allocator> bool deque<T, Allocator>::empty() const{
		return (elements == 0);
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::reference deque<T, Allocator>::operator[](size_type n)
	{
		return data[array_element(n)];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reference deque<T, Allocator>::operator[](size_type n) const
	{
		return data[array_element(n)];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::reference deque<T, Allocator>::at(size_type n)
	{
		if(n > elements){
			__throw_out_of_range("Out of deque range");
		}
		return data[array_element(n)];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reference deque<T, Allocator>::at(size_type n) const
	{
		if(n > elements){
			__throw_out_of_range("Out of deque range");
		}
		return data[array_element(n)];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::reference deque<T, Allocator>::front()
	{
		return data[first_element];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reference deque<T, Allocator>::front() const
	{
		return data[first_element];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::reference deque<T, Allocator>::back()
	{
		return data[array_element(elements-1)];
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::const_reference deque<T, Allocator>::back() const
	{
		return data[array_element(elements-1)];
	}
	
	template<class T, class Allocator> void deque<T, Allocator>::push_front(const T& x){
		reserve(elements + 1);
		first_element = first_subtract(1);
		a.construct(data + first_element, x);
		++elements;
	}

	template<class T, class Allocator> void deque<T, Allocator>::push_back(const T& x){
		reserve(elements + 1);
		a.construct(data + last_element, x);
		++elements;
		last_element = array_element(elements);
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::iterator deque<T, Allocator>::insert(iterator position, const T& x)
	{
		reserve(elements+1);
		if(position.element > (elements/2)){
			//Push all elements back 1
			push_back(x);
			for(size_type i = elements-1; i > position.element; --i){
				at(i) = at(i-1);
			}
		}else{
			//Push all elements forward 1
			push_front(x);
			for(size_type i = 0; i < position.element; ++i){
				at(i) = at(i+1);
			}
		}
		at(position.element) = x;
		return deque_iter(this, position.element);
	}

	template<class T, class Allocator> void deque<T, Allocator>::
		insert(typename deque<T, Allocator>::iterator position, size_type n, const T& x)
	{
		reserve(elements + n);
		for(size_t i =0; i < n; ++i){
			position = insert(position, x);
		}
	}

	template<class T, class Allocator> template <class InputIterator> 
		void deque<T, Allocator>::insert (iterator position, InputIterator first, InputIterator last)
	{
		while(first != last){
			position = insert(position, *first);
			++first;
		}
	}

	template<class T, class Allocator> void deque<T, Allocator>::pop_front(){
		if(elements == 0){
			__throw_out_of_range("deque pop_front");
		}
		a.destroy(data + first_element);
		first_element = array_element(1);
		--elements;
	}

	template<class T, class Allocator> void deque<T, Allocator>::pop_back(){
		last_element = array_element(elements - 1);
		a.destroy(data + last_element);
		--elements;
	}

	template<class T, class Allocator> typename
		deque<T, Allocator>::iterator deque<T, Allocator>::erase(typename deque<T, Allocator>::iterator position)
	{
		if(position.element > (elements /2)){
			for(size_type i = position.element; i < elements - 1; ++i){
				at(i) = at(i+1);
			}
			pop_back();
		}else{
			for(size_type i = position.element; i > 0; --i){
				at(i) = at(i-1);
			}
			pop_front();
		}
		return deque_iter(this, position.element);
	}

	template<class T, class Allocator> typename deque<T, Allocator>::iterator 
		deque<T, Allocator>::
		erase(typename deque<T, Allocator>::iterator first, typename deque<T, Allocator>::iterator last)
	{
		//Shift backwards
		size_type num_move = last.element - first.element;
		if( first.element > (elements - last.element) ){
			for(size_type i = last.element; i < elements ; ++i){
				at(i-num_move) = at(i);
			}
			for(size_type i = 0; i < num_move ; ++i){
				pop_back();
			}
		}else{
			for(size_type i = 0; i < first.element ; ++i){
				at(last.element - i - 1) = at(first.element - i - 1);
			}
			for(size_type i = 0; i < num_move ; ++i){
				pop_front();
			}
		}
		return deque_iter(this, first.element);
	}

	template<class T, class Allocator> void deque<T, Allocator>::swap(deque<T,Allocator>& x)
	{
		T * temp_data;
		typename deque<T,Allocator>::size_type temp_size;

		//Swap data pointers
		temp_data = x.data;
		x.data = data;
		data = temp_data;

		//Swap array sizes
		temp_size = x.data_size;
		x.data_size = data_size;
		data_size = temp_size;

		//Swap num array elements
		temp_size  = x.elements;
		x.elements = elements;
		elements = temp_size;

		//Swap first_pointer
		temp_size = x.first_element;
		x.first_element = first_element;
		first_element = temp_size;

		//Swap last_pointer
		temp_size = x.last_element;
		x.last_element = last_element;
		last_element = temp_size;
	}

	template<class T, class Allocator> void deque<T, Allocator>::clear()
	{
		while(elements > 0 ){
			pop_back();
		}
	}


	template<class T, class Allocator> void deque<T, Allocator>::reserve(typename deque<T, Allocator>::size_type n)
	{
		if(data_size >= n){
			return;
		}

		size_type size_temp;
		size_type first_temp;
		T * data_temp;
		size_temp = n + __UCLIBCXX_STL_BUFFER_SIZE__;		//Reserve extra 'cause we can
		data_temp = a.allocate(size_temp);
	
		first_temp = (size_temp - elements) / 2;
		for(size_type i = 0; i < elements; ++i){
			a.construct(data_temp + first_temp + i, data[array_element(i)]);
			a.destroy(data + array_element(i));
		}

		//Now shuffle pointers
		a.deallocate(data, data_size);
		data = data_temp;
		data_size = size_temp;
		first_element = first_temp;
		last_element = first_element + elements;
	}


	template <class T, class Allocator> _UCXXEXPORT 
		bool
		operator==(const deque<T,Allocator>& x, const deque<T,Allocator>& y)
	{
		if(x.elements != y.elements){
			return false;
		}
		for(typename deque<T,Allocator>::size_type i = 0; i < x.elements; ++i){
			if(x[i] < y[i] || y[i] < x[i]){
				return false;
			}
		}
		return true;
	}

	template <class T, class Allocator> bool operator< (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> _UCXXEXPORT
		bool
		operator!=(const deque<T,Allocator>& x, const deque<T,Allocator>& y)
	{
		if(x == y){
			return false;
		}
		return true;
	}
	template <class T, class Allocator> bool operator> (const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator>=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> bool operator<=(const deque<T,Allocator>& x, const deque<T,Allocator>& y);
	template <class T, class Allocator> _UCXXEXPORT void swap(deque<T,Allocator>& x, deque<T,Allocator>& y){
		x.swap(y);
	}



}

#endif