/*
https://github.com/peterix/dfhack
Copyright (c) 2009-2012 Petr Mrázek (peterix@gmail.com)

This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any
damages arising from the use of this software.

Permission is granted to anyone to use this software for any
purpose, including commercial applications, and to alter it and
redistribute it freely, subject to the following restrictions:

1. The origin of this software must not be misrepresented; you must
not claim that you wrote the original software. If you use this
software in a product, an acknowledgment in the product documentation
would be appreciated but is not required.

2. Altered source versions must be plainly marked as such, and
must not be misrepresented as being the original software.

3. This notice may not be removed or altered from any source
distribution.
*/

#pragma once
#include "Pragma.h"
#include "Export.h"
#include "Error.h"
#include <stdint.h>
#include <string.h>
#include <stdlib.h>
#include <sstream>
#include <exception>
#include <type_traits>
#include <iterator>
namespace DFHack
{
    template <typename T = int>
    class BitArray
    {
    public:
        BitArray() : bits(NULL), size(0) {}
        BitArray(const BitArray<T> &other) : bits(NULL), size(0)
        {
            *this = other;
        }
        ~BitArray()
        {
            free(bits);
        }

        explicit BitArray(T last) : bits(NULL), size(0) {
            extend(last);
        }
        explicit BitArray(unsigned bytes) : bits(NULL), size(0) {
            resize(bytes);
        }

        void clear_all ( void )
        {
            if(bits)
                memset(bits, 0, size);
        }
        void resize (unsigned newsize)
        {
            if (newsize == size)
                return;
            uint8_t* mem = (uint8_t *) realloc(bits, newsize);
            if(!mem && newsize != 0)
                throw std::bad_alloc();
            bits = mem;
            if (newsize > size)
                memset(bits+size, 0, newsize-size);
            size = newsize;
        }
        BitArray<T> &operator= (const BitArray<T> &other)
        {
            resize(other.size);
            memcpy(bits, other.bits, size);
            return *this;
        }
        void extend (T index)
        {
            unsigned newsize = (index / 8) + 1;
            if (newsize > size)
                resize(newsize);
        }
        void set (T index, bool value = true)
        {
            if(!value)
            {
                clear(index);
                return;
            }
            uint32_t byte = index / 8;
            extend(index);
            //if(byte < size)
            {
                uint8_t bit = 1 << (index % 8);
                bits[byte] |= bit;
            }
        }
        void clear (T index)
        {
            uint32_t byte = index / 8;
            if(byte < size)
            {
                uint8_t bit = 1 << (index % 8);
                bits[byte] &= ~bit;
            }
        }
        void toggle (T index)
        {
            uint32_t byte = index / 8;
            extend(index);
            //if(byte < size)
            {
                uint8_t bit = 1 << (index % 8);
                bits[byte] ^= bit;
            }
        }
        bool is_set (T index) const
        {
            uint32_t byte = index / 8;
            if(byte < size)
            {
                uint8_t bit = 1 << (index % 8);
                return bit & bits[byte];
            }
            else return false;
        }
        /// WARNING: this can truncate long bit arrays
        uint32_t as_int ()
        {
            if(!bits)
                return 0;
            if(size >= 4)
                return  *(uint32_t *)bits;
            uint32_t target = 0;
            memcpy (&target, bits,size);
            return target;
        }
        /// WARNING: this can be truncated / only overwrite part of the data
        bool operator =(uint32_t data)
        {
            if(!bits)
                return false;
            if (size >= 4)
            {
                (*(uint32_t *)bits) = data;
                return true;
            }
            memcpy(bits, &data, size);
            return true;
        }
        friend std::ostream& operator<< (std::ostream &out, BitArray <T> &ba)
        {
            std::stringstream sstr;
            for (int i = 0; i < ba.size * 8; i++)
            {
                if(ba.is_set((T)i))
                    sstr << "1 ";
                else
                    sstr << "0 ";
            }
            out << sstr.str();
            return out;
        }
        uint8_t * bits;
        uint32_t size;
    };

    template <typename T = int>
    class DfArray
    {
        T *m_data;
        unsigned short m_size;
    public:
        DfArray() : m_data(NULL), m_size(0) {}
        ~DfArray() { free(m_data); }

        DfArray(const DfArray<T> &other) : m_data(NULL), m_size(0)
        {
            resize(other.m_size);
            memcpy(m_data, other.m_data,m_size*sizeof(T));
        }

        typedef T value_type;

        T *data() { return m_data; }
        const T *data() const { return m_data; }
        unsigned size() const { return m_size; }

        T *begin() { return m_data; }
        T *end() { return m_data+m_size; }

        T& operator[] (unsigned i) { return m_data[i]; }
        const T& operator[] (unsigned i) const { return m_data[i]; }

        void resize(unsigned new_size)
        {
            if (new_size == m_size)
                return;
            if(!m_data)
            {
                m_data = (T*) malloc(sizeof(T)*new_size);
            }
            else
            {
                T* mem = (T*) realloc(m_data, sizeof(T)*new_size);
                if(!mem && new_size != 0)
                    throw std::bad_alloc();
                m_data = mem;
            }
            if (new_size > m_size)
                memset(m_data+sizeof(T)*m_size, 0, sizeof(T)*(new_size - m_size));
            m_size = new_size;
        }

        DfArray &operator= (const DfArray<T> &other)
        {
            resize(other.size());
            memcpy(data(), other.data(), sizeof(T)*size());
            return *this;
        }

        void erase(T *ptr) {
            memmove(ptr, ptr+1, sizeof(T)*(m_size - (ptr - m_data))); m_size--;
        }
        void insert(T *ptr, const T &item) {
            int idx = ptr - m_data;
            resize(m_size+1);
            memmove(m_data + idx + 1, m_data + idx, sizeof(T)*(m_size - idx - 1));
            m_data[idx] = item;
        }
    };

    template <typename L, typename I>
    struct DfLinkedList
    {
        class iterator;
        class const_iterator;

        class proxy
        {
            L *root;
            L *prev;
            friend class iterator;
            proxy(L *root, L *prev) : root(root), prev(prev)
            {
                CHECK_NULL_POINTER(root);
                CHECK_NULL_POINTER(prev);
            }

        public:
            operator I * & ()
            {
                CHECK_NULL_POINTER(prev->next);
                return prev->next->item;
            }
            operator I *() const
            {
                CHECK_NULL_POINTER(prev->next);
                return prev->next->item;
            }
            I *operator->() const
            {
                CHECK_NULL_POINTER(prev->next);
                return prev->next->item;
            }
            proxy & operator=(I *item)
            {
                if (!prev->next)
                {
                    prev->next = new L();
                    if (prev != root)
                        prev->next->prev = prev;
                }
                prev->next->item = item;
                return *this;
            }
        };

        class iterator
        {
            L *root;
            L *prev;
            bool next;
            friend struct DfLinkedList<L, I>;
            friend class const_iterator;
            void ensure_prev()
            {
                CHECK_NULL_POINTER(root);
                if (!prev && !next)
                {
                    for (prev = root; prev->next && prev->next->next; prev = prev->next)
                    {
                        next = true;
                    }
                }
            }
            iterator() : root(nullptr), prev(nullptr), next(false) {}
        public:
            using difference_type = void;
            using value_type = I *;
            using pointer = I **;
            using reference = proxy;
            using iterator_category = std::output_iterator_tag;

            iterator(L *root, L *prev, bool next = false) : root(root), prev(prev), next(next) {}
            iterator(const iterator & other) : root(other.root), prev(other.prev), next(other.next) {}

            iterator & operator++()
            {
                CHECK_NULL_POINTER(root);

                CHECK_NULL_POINTER(prev);
                CHECK_NULL_POINTER(prev->next);

                if (!next && !prev->next->next)
                {
                    next = true;
                    return *this;
                }

                CHECK_NULL_POINTER(prev->next->next);

                prev = prev->next;
                return *this;
            }
            iterator & operator--()
            {
                CHECK_NULL_POINTER(root);

                ensure_prev();

                if (next)
                {
                    next = false;
                    return *this;
                }

                CHECK_NULL_POINTER(prev);
                if (prev == root)
                {
                    throw DFHack::Error::NullPointer("prev->prev", DFHACK_FUNCTION_SIG);
                }

                if (root->next == prev)
                {
                    prev = root;
                    return *this;
                }

                if (prev->prev)
                {
                    prev = prev->prev;
                    return *this;
                }

                for (L *it = root; it->next; it = it->next)
                {
                    if (it->next == prev)
                    {
                        prev = it;
                        return *this;
                    }
                }

                throw DFHack::Error::NullPointer("prev->prev", DFHACK_FUNCTION_SIG);
            }
            iterator operator++(int)
            {
                iterator copy(*this);
                ++*this;
                return copy;
            }
            iterator operator--(int)
            {
                iterator copy(*this);
                --*this;
                return copy;
            }
            iterator & operator=(const iterator & other)
            {
                root = other.root;
                prev = other.prev;
                next = other.next;
                return *this;
            }

            proxy operator*()
            {
                CHECK_NULL_POINTER(prev);
                CHECK_NULL_POINTER(prev->next);

                if (next)
                    return proxy(root, prev->next);

                return proxy(root, prev);
            }

            const proxy operator*() const
            {
                CHECK_NULL_POINTER(prev);
                CHECK_NULL_POINTER(prev->next);

                if (next)
                    return proxy(root, prev->next);

                return proxy(root, prev);
            }

            I * operator->() const
            {
                return **this;
            }

            operator const_iterator() const
            {
                return const_iterator(*this);
            }
            bool operator==(const iterator & other) const
            {
                if (root != other.root)
                    return false;

                if (!next && !prev && !other.next && !other.prev)
                    return true;

                if ((!next && !prev) || (!other.next && !other.prev))
                {
                    iterator this_copy = *this;
                    this_copy.ensure_prev();
                    iterator other_copy = other;
                    other_copy.ensure_prev();
                    return this_copy == other_copy;
                }

                if (other.next && !next)
                    return prev && other.prev && prev->next == other.prev;
                if (next && !other.next)
                    return prev && other.prev && other.prev->next == prev;
                return other.prev == prev;
            }
            bool operator!=(const iterator & other) const
            {
                return !(*this == other);
            }
        };
        class const_iterator
        {
            iterator iter;
            friend struct DfLinkedList<L, I>;
        public:
            using difference_type = void;
            using value_type = I * ;
            using pointer = I * const *;
            using reference = const proxy;
            using iterator_category = std::bidirectional_iterator_tag;

            const_iterator(const iterator & iter) : iter(iter) {}
            const_iterator(const const_iterator & other) : iter(other.iter) {}

            const_iterator & operator++()
            {
                ++iter;
                return *this;
            }
            const_iterator & operator--()
            {
                --iter;
                return *this;
            }
            const_iterator operator++(int)
            {
                const_iterator copy(*this);
                ++*this;
                return copy;
            }
            const_iterator operator--(int)
            {
                const_iterator copy(*this);
                --*this;
                return copy;
            }
            const_iterator & operator=(const const_iterator & other)
            {
                iter = other.iter;
                return *this;
            }
            const proxy operator*() const
            {
                return *iter;
            }
            I *operator->() const
            {
                return *iter;
            }
            bool operator==(const const_iterator & other) const
            {
                return iter == other.iter;
            }
            bool operator!=(const const_iterator & other) const
            {
                return iter != other.iter;
            }
        };

        typedef I *value_type;
        typedef I * & reference_type;
        typedef void difference_type;
        typedef size_t size_type;

        bool empty() const
        {
            return static_cast<const L *>(this)->next == nullptr;
        }
        size_t size() const
        {
            size_t n = 0;
            for (I *i : *this)
                n++;
            return n;
        }

        iterator begin()
        {
            return iterator(static_cast<L *>(this), static_cast<L *>(this));
        }
        const_iterator begin() const
        {
            return const_iterator(static_cast<L *>(this), static_cast<L *>(this));
        }
        const_iterator cbegin() const
        {
            return begin();
        }
        iterator end()
        {
            return iterator(static_cast<L *>(this), nullptr, false);
        }
        const_iterator end() const
        {
            return const_iterator(static_cast<L *>(this), nullptr, false);
        }
        const_iterator cend() const
        {
            return end();
        }
    };
}