#include <psemek/audio/recorder.hpp>

#include <vector>

namespace psemek::audio
{

	namespace
	{

		struct recorder_impl
			: recorder
		{
			recorder_impl(stream_ptr stream)
				: stream_(std::move(stream))
			{}

			recorder_impl(std::vector<float> samples)
				: buffer_(std::move(samples))
				, length_(buffer_.size())
			{}

			std::optional<std::size_t> length() const override
			{
				return stream_ ? stream_->length() : buffer_.size();
			}

			std::size_t request(std::size_t samples) override
			{
				if (!stream_)
					return 0;

				if (buffer_.size() < length_ + samples)
					buffer_.resize(std::max<std::size_t>(samples, buffer_.size() * 2));

				auto result = stream_->read(buffer_.data() + length_, samples);
				length_ += result;
				return result;
			}

			util::span<float const> buffer() const override
			{
				return {buffer_.data(), buffer_.data() + length_};
			}

		private:
			stream_ptr stream_;
			std::vector<float> buffer_;
			std::size_t length_{0};
		};

	}

	std::shared_ptr<recorder> make_recorder(stream_ptr stream)
	{
		return std::make_shared<recorder_impl>(std::move(stream));
	}

	std::shared_ptr<recorder> make_recorder(std::vector<float> samples)
	{
		return std::make_shared<recorder_impl>(std::move(samples));
	}

}