#pragma once

#include "cvmmap_streamer/config/runtime_config.hpp"

#include <chrono>
#include <cstdint>
#include <expected>
#include <span>
#include <string>
#include <string_view>
#include <vector>

namespace cvmmap_streamer::protocol {

struct RtmpPublisherStats {
	std::uint64_t access_units{0};
	std::uint64_t access_unit_bytes{0};
	std::uint64_t video_messages{0};
	std::uint64_t bytes_sent{0};
	std::uint64_t send_errors{0};
	std::uint64_t publish_failures{0};
	std::uint64_t reconnect_attempts{0};
	std::uint64_t reconnect_successes{0};
	std::uint64_t reconnect_failures{0};
};

class RtmpPublisher {
public:
	RtmpPublisher() = default;
	~RtmpPublisher();

	RtmpPublisher(const RtmpPublisher &)            = delete;
	RtmpPublisher &operator=(const RtmpPublisher &) = delete;

	RtmpPublisher(RtmpPublisher &&other) noexcept;
	RtmpPublisher &operator=(RtmpPublisher &&other) noexcept;

	[[nodiscard]]
	static std::expected<RtmpPublisher, std::string> create(const RuntimeConfig &config);

	[[nodiscard]]
	std::expected<void, std::string> publish_access_unit(std::span<const std::uint8_t> access_unit, std::uint64_t pts_ns);

	[[nodiscard]]
	const RtmpPublisherStats &stats() const;

	void on_stream_reset();

	void log_metrics() const;

private:
	struct Session {
		std::string original_url{};
		std::string host{};
		std::uint16_t port{1935};
		std::string app{};
		std::string stream{};
		std::string tc_url{};
		int socket_fd{-1};
		std::uint32_t out_chunk_size{128};
		std::uint32_t stream_id{1};
		bool sequence_header_sent{false};
		std::uint32_t reconnect_backoff_ms{250};
		std::uint32_t consecutive_reconnect_failures{0};
		std::chrono::steady_clock::time_point reconnect_due_at{};
		bool in_cooldown{false};
	};

	[[nodiscard]]
	std::expected<void, std::string> connect_session(Session &session);

	void schedule_reconnect(Session &session, std::string_view reason, bool startup_path);

	void close_session(Session &session);

	CodecType codec_{CodecType::H264};
	RtmpMode mode_{RtmpMode::Enhanced};
	std::vector<Session> sessions_{};
	RtmpPublisherStats stats_{};
	bool had_successful_video_message_{false};
	bool warned_all_sessions_closed_{false};
};

}