export module map;

import std;

namespace brc {

export struct entry {
	std::uint64_t key_hash = 0;
	const char* key_ptr = nullptr;								  // 8, 8
	std::int64_t total = 0;										  // 8, 26
	std::int32_t min = std::numeric_limits<std::int32_t>::max();  // 4, 12
	std::int32_t max = std::numeric_limits<std::int32_t>::min();  // 4, 16
	std::uint32_t count = 0;									  // 4, 30
	std::uint16_t key_len = 0;									  // 2, 32
};

export class map {
private:
	std::size_t entry_count;
	std::unique_ptr<entry[]> entries;

	[[nodiscard]] static std::uint64_t get_key(std::string_view city) noexcept;

	[[nodiscard]] std::uint64_t get_index(std::string_view city) const noexcept;

public:
	explicit map(std::size_t entry_count);

	void insert(std::string_view city, std::int32_t measurement);

	[[nodiscard]] entry& operator[](std::string_view city);

	void merge_against(const map& other);

	[[nodiscard]] std::vector<entry> collapse() const noexcept;
};

}  // namespace brc