#include <psemek/ecs/detail/table.hpp>
#include <psemek/ecs/detail/component_hash.hpp>

namespace psemek::ecs::detail
{

	table::table(std::vector<std::unique_ptr<detail::column>> columns)
	{
		component_hasher hasher;
		for (auto & column : columns)
		{
			auto uuid = column->uuid();
			hasher(uuid);
			component_uuid_to_column_.insert({uuid, std::move(column)});
		}
		hash_ = hasher.result;
	}

	detail::column * table::column(util::uuid const & uuid) const
	{
		if (auto it = component_uuid_to_column_.find(uuid); it != component_uuid_to_column_.end())
			return it->second.get();
		return nullptr;
	}

	std::size_t table::push_row(entity_handle handle)
	{
		for (auto & pair : component_uuid_to_column_)
			pair.second->push_row();
		entity_handles_.push_back(handle);
		return entity_handles_.size() - 1;
	}

	void table::swap_rows(std::size_t row1, std::size_t row2)
	{
		for (auto & pair : component_uuid_to_column_)
			pair.second->swap_rows(row1, row2);
		std::swap(entity_handles_[row1], entity_handles_[row2]);
	}

	void table::pop_row()
	{
		for (auto & pair : component_uuid_to_column_)
			pair.second->pop_row();
		entity_handles_.pop_back();
	}

	void table::clear()
	{
		for (auto & pair : component_uuid_to_column_)
			pair.second->clear();
		entity_handles_.clear();
	}

	void table::push_remove(std::uint32_t row)
	{
		remove_queue_.push_back(row);
	}

	std::vector<std::uint32_t> table::grab_remove_queue()
	{
		return std::move(remove_queue_);
	}

	std::unique_ptr<table> table::clone() const
	{
		std::vector<std::unique_ptr<detail::column>> columns;
		for (auto const & pair : component_uuid_to_column_)
			columns.push_back(pair.second->clone());
		return std::make_unique<table>(std::move(columns));
	}

	table * table::get_delayed_table()
	{
		if (!delayed_table_)
			delayed_table_ = clone();
		return delayed_table_.get();
	}

	util::span<entity_handle const> table::flush_delayed()
	{
		if (!delayed_table_)
			return {};

		std::size_t count = delayed_table_->row_count();
		for (auto & pair : component_uuid_to_column_)
		{
			auto * src_column = delayed_table_->column(pair.second->uuid());
			pair.second->emplace_rows(src_column->data(), count);
		}
		entity_handles_.insert(entity_handles_.end(), delayed_table_->entity_handles_.begin(), delayed_table_->entity_handles_.end());

		delayed_table_->clear();

		return {entity_handles_.data() + entity_handles_.size() - count, count};
	}

}