unordered_map.hpp

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#ifndef NEFORCE_CORE_CONTAINER_UNORDERED_MAP_HPP__
#define NEFORCE_CORE_CONTAINER_UNORDERED_MAP_HPP__

 
#include "NeForce/core/container/hashtable.hpp"
NEFORCE_BEGIN_NAMESPACE__


template <typename Key, typename T, typename HashFcn = hash<Key>, typename EqualKey = equal_to<Key>,
          typename Alloc = allocator<hashtable_node<pair<const Key, T>>>>
class unordered_map : public icollector<unordered_map<Key, T, HashFcn, EqualKey, Alloc>> {
    static_assert(is_hash_v<HashFcn, Key>, "unordered map requires valid hash function.");
    static_assert(is_allocator_v<Alloc>, "Alloc type is not a standard allocator type.");
    static_assert(is_same_v<hashtable_node<pair<const Key, T>>, typename Alloc::value_type>,
                  "allocator type mismatch.");
    static_assert(is_object_v<Key>, "unordered map only contains object types.");
 
    using base_type = hashtable<pair<const Key, T>, Key, HashFcn, select1st<pair<const Key, T>>, EqualKey,
                                Alloc>; 
 
public:
    using key_type = typename base_type::key_type;     
    using value_type = typename base_type::value_type; 
    using hasher = typename base_type::hasher;         
    using key_equal = typename base_type::key_equal;   
 
    using size_type = typename base_type::size_type;             
    using difference_type = typename base_type::difference_type; 
    using pointer = typename base_type::pointer;                 
    using const_pointer = typename base_type::const_pointer;     
    using reference = typename base_type::reference;             
    using const_reference = typename base_type::const_reference; 
    using iterator = typename base_type::iterator;               
    using const_iterator = typename base_type::const_iterator;   
    using allocator_type = typename base_type::allocator_type;   
 
private:
    base_type ht_{100}; 
 
public:
    unordered_map() = default;

    explicit unordered_map(size_type n) :
    ht_(n) {}

    unordered_map(size_type n, const hasher& hf) :
    ht_(n, hf, key_equal()) {}

    unordered_map(size_type n, const hasher& hf, const key_equal& eql) :
    ht_(n, hf, eql) {}

    unordered_map(const unordered_map& other) :
    ht_(other.ht_) {}

    unordered_map& operator=(const unordered_map& other) {
        ht_ = other.ht_;
        return *this;
    }

    unordered_map(unordered_map&& other) noexcept(is_nothrow_move_constructible_v<base_type>) :
    ht_(_NEFORCE move(other.ht_)) {}

    unordered_map& operator=(unordered_map&& other) noexcept(is_nothrow_move_assignable_v<base_type>) {
        ht_ = _NEFORCE move(other.ht_);
        return *this;
    }

    template <typename Iterator>
    unordered_map(Iterator first, Iterator last) :
    ht_(100, hasher(), key_equal()) {
        ht_.insert_unique(first, last);
    }

    template <typename Iterator>
    unordered_map(Iterator first, Iterator list, size_type n) :
    ht_(n, hasher(), key_equal()) {
        ht_.insert_unique(first, list);
    }

    template <typename Iterator>
    unordered_map(Iterator first, Iterator last, size_type n, const hasher& hf) :
    ht_(n, hf, key_equal()) {
        ht_.insert_unique(first, last);
    }

    template <typename Iterator>
    unordered_map(Iterator first, Iterator last, size_type n, const hasher& hf, const key_equal& eql) :
    ht_(n, hf, eql) {
        ht_.insert_unique(first, last);
    }

    unordered_map(std::initializer_list<value_type> ilist) :
    unordered_map(ilist.begin(), ilist.end()) {}

    unordered_map(std::initializer_list<value_type> ilist, size_type n) :
    unordered_map(ilist.begin(), ilist.end(), n) {}

    unordered_map(std::initializer_list<value_type> ilist, size_type n, const hasher& hf) :
    unordered_map(ilist.begin(), ilist.end(), n, hf) {}

    unordered_map(std::initializer_list<value_type> ilist, size_type n, const hasher& hf, const key_equal& eql) :
    unordered_map(ilist.begin(), ilist.end(), n, hf, eql) {}

    NEFORCE_NODISCARD iterator begin() noexcept { return ht_.begin(); }

    NEFORCE_NODISCARD iterator end() noexcept { return ht_.end(); }

    NEFORCE_NODISCARD const_iterator begin() const noexcept { return ht_.begin(); }

    NEFORCE_NODISCARD const_iterator end() const noexcept { return ht_.end(); }

    NEFORCE_NODISCARD const_iterator cbegin() const noexcept { return ht_.cbegin(); }

    NEFORCE_NODISCARD const_iterator cend() const noexcept { return ht_.cend(); }

    NEFORCE_NODISCARD size_type size() const noexcept { return ht_.size(); }

    NEFORCE_NODISCARD size_type max_size() const noexcept { return ht_.max_size(); }

    NEFORCE_NODISCARD bool empty() const noexcept { return ht_.empty(); }

    NEFORCE_NODISCARD size_type count(const key_type& key) const noexcept(noexcept(ht_.count(key))) {
        return ht_.count(key);
    }

    NEFORCE_NODISCARD size_type buckets_size() const noexcept { return ht_.buckets_size(); }

    NEFORCE_NODISCARD size_type buckets_max_count() const noexcept { return ht_.buckets_max_size(); }

    NEFORCE_NODISCARD size_type bucket_size(size_type n) const noexcept { return ht_.bucket_size(n); }

    NEFORCE_NODISCARD hasher hash_function() const noexcept(noexcept(ht_.hash_function())) {
        return ht_.hash_function();
    }

    NEFORCE_NODISCARD key_equal key_eql() const noexcept(noexcept(ht_.key_eql())) { return ht_.key_eql(); }

    NEFORCE_NODISCARD float load_factor() const noexcept { return ht_.load_factor(); }

    NEFORCE_NODISCARD float max_load_factor() const noexcept { return ht_.max_load_factor(); }

    void max_load_factor(float lf) noexcept { ht_.max_load_factor(lf); }

    void rehash(size_type n) { ht_.rehash(n); }

    void reserve(size_type n) { ht_.reserve(n); }

    template <typename... Args>
    pair<iterator, bool> emplace(Args&&... args) {
        return ht_.emplace_unique(_NEFORCE forward<Args>(args)...);
    }

    pair<iterator, bool> insert(const value_type& value) { return ht_.insert_unique(value); }

    pair<iterator, bool> insert(value_type&& value) { return ht_.insert_unique(_NEFORCE forward<value_type>(value)); }

    template <typename Iterator>
    void insert(Iterator first, Iterator last) {
        ht_.insert_unique(first, last);
    }

    size_type erase(const key_type& key) noexcept { return ht_.erase(key); }

    iterator erase(iterator position) noexcept { return ht_.erase(position); }

    iterator erase(iterator first, iterator last) noexcept { return ht_.erase(first, last); }

    const_iterator erase(const_iterator position) noexcept { return ht_.erase(position); }

    const_iterator erase(const_iterator first, const_iterator last) noexcept { return ht_.erase(first, last); }

    void clear() noexcept { ht_.clear(); }

    NEFORCE_NODISCARD iterator find(const key_type& key) { return ht_.find(key); }

    NEFORCE_NODISCARD const_iterator find(const key_type& key) const { return ht_.find(key); }

    NEFORCE_NODISCARD pair<iterator, iterator> equal_range(const key_type& key) { return ht_.equal_range(key); }

    NEFORCE_NODISCARD pair<const_iterator, const_iterator> equal_range(const key_type& key) const {
        return ht_.equal_range(key);
    }

    NEFORCE_NODISCARD T& operator[](const key_type& key) {
        auto iter = ht_.find(key);
        if (iter == ht_.end()) {
            iter = ht_.emplace_unique(key, T()).first;
        }
        return iter->second;
    }

    NEFORCE_NODISCARD const T& at(const key_type& key) const {
        auto iter = ht_.find(key);
        if (iter == end()) {
            NEFORCE_THROW_EXCEPTION(iterator_exception("unordered_map key-value does not exists"));
        }
        return iter->second;
    }

    NEFORCE_NODISCARD T& at(const key_type& key) {
        auto iter = ht_.find(key);
        if (iter == end()) {
            NEFORCE_THROW_EXCEPTION(iterator_exception("unordered_map key-value does not exists"));
        }
        return iter->second;
    }

    void swap(unordered_map& other) noexcept(is_nothrow_swappable_v<base_type>) { ht_.swap(other.ht_); }

    NEFORCE_NODISCARD bool equal_to(const unordered_map& rhs) const noexcept(noexcept(ht_ == rhs.ht_)) {
        return ht_ == rhs.ht_;
    }

    NEFORCE_NODISCARD bool less_than(const unordered_map& rhs) const noexcept(noexcept(ht_ < rhs.ht_)) {
        return ht_ < rhs.ht_;
    }
};
 
#ifdef NEFORCE_STANDARD_17
template <typename Iterator, typename HashFcn = hash<iter_map_key_t<Iterator>>,
          typename Compare = equal_to<iter_map_key_t<Iterator>>, typename Alloc>
unordered_map(Iterator, Iterator, HashFcn = HashFcn(), Compare = Compare(), Alloc = Alloc())
        -> unordered_map<iter_map_key_t<Iterator>, iter_map_value_t<Iterator>, HashFcn, Compare, Alloc>;
 
template <typename Key, typename T, typename HashFcn = hash<Key>, typename Compare = equal_to<Key>,
          typename Alloc = allocator<pair<const Key, T>>>
unordered_map(std::initializer_list<pair<Key, T>>, HashFcn = HashFcn(), Compare = Compare(), Alloc = Alloc())
        -> unordered_map<Key, T, HashFcn, Compare, Alloc>;
 
template <typename Iterator, typename Alloc>
unordered_map(Iterator, Iterator, Alloc)
        -> unordered_map<iter_map_key_t<Iterator>, iter_map_value_t<Iterator>, hash<iter_map_key_t<Iterator>>,
                         equal_to<iter_map_key_t<Iterator>>, Alloc>;
 
template <typename Iterator, typename HashFcn, typename Alloc>
unordered_map(Iterator, Iterator, HashFcn, Alloc) -> unordered_map<iter_map_key_t<Iterator>, iter_map_value_t<Iterator>,
                                                                   HashFcn, equal_to<iter_map_key_t<Iterator>>, Alloc>;
 
template <typename Key, typename T, typename Alloc>
unordered_map(std::initializer_list<pair<Key, T>>, Alloc) -> unordered_map<Key, T, hash<Key>, equal_to<Key>, Alloc>;
 
template <typename Key, typename T, typename HashFcn, typename Alloc>
unordered_map(std::initializer_list<pair<Key, T>>, HashFcn, Alloc)
        -> unordered_map<Key, T, HashFcn, equal_to<Key>, Alloc>;
#endif
 // Container
 
NEFORCE_END_NAMESPACE__
#endif // NEFORCE_CORE_CONTAINER_UNORDERED_MAP_HPP__