// Copyright(c) 2015-present, Gabi Melman & spdlog contributors.
// Distributed under the MIT License (http://opensource.org/licenses/MIT)

#pragma once

#include "spdlog/sinks/base_sink.h"
#include "spdlog/details/file_helper.h"
#include "spdlog/details/null_mutex.h"
#include "spdlog/details/synchronous_factory.h"

#include <chrono>
#include <mutex>
#include <string>

namespace spdlog {
namespace sinks {

//
// Rotating file sink based on size
//
template<typename Mutex>
class rotating_file_sink final : public base_sink<Mutex>
{
public:
    rotating_file_sink(filename_t base_filename, std::size_t max_size, std::size_t max_files, bool rotate_on_open = false);
    static filename_t calc_filename(const filename_t &filename, std::size_t index);
    const filename_t &filename() const;

protected:
    void sink_it_(const details::log_msg &msg) override;
    void flush_() override;

private:
    // Rotate files:
    // log.txt -> log.1.txt
    // log.1.txt -> log.2.txt
    // log.2.txt -> log.3.txt
    // log.3.txt -> delete
    void rotate_();

    // delete the target if exists, and rename the src file  to target
    // return true on success, false otherwise.
    bool rename_file(const filename_t &src_filename, const filename_t &target_filename);

    filename_t base_filename_;
    std::size_t max_size_;
    std::size_t max_files_;
    std::size_t current_size_;
    details::file_helper file_helper_;
};

using rotating_file_sink_mt = rotating_file_sink<std::mutex>;
using rotating_file_sink_st = rotating_file_sink<details::null_mutex>;

} // namespace sinks

//
// factory functions
//

template<typename Factory = spdlog::synchronous_factory>
inline std::shared_ptr<logger> rotating_logger_mt(
    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false)
{
    return Factory::template create<sinks::rotating_file_sink_mt>(logger_name, filename, max_file_size, max_files, rotate_on_open);
}

template<typename Factory = spdlog::synchronous_factory>
inline std::shared_ptr<logger> rotating_logger_st(
    const std::string &logger_name, const filename_t &filename, size_t max_file_size, size_t max_files, bool rotate_on_open = false)
{
    return Factory::template create<sinks::rotating_file_sink_st>(logger_name, filename, max_file_size, max_files, rotate_on_open);
}
} // namespace spdlog

#ifdef SPDLOG_HEADER_ONLY
#include "rotating_file_sink-inl.h"
#endif