//
// Copyright 2017 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//

#pragma once

#include <mpm/noncopyable.hpp>
#include <boost/circular_buffer.hpp>
#include <cstddef>
#include <functional>
#include <memory>
#include <mutex>
#include <string>
#include <tuple>

namespace mpm { namespace types {

//! Log levels, designed to match the ones in mpmlog.py
enum class log_level_t {
    NONE     = 0, //!< Use this when there's actually no message
    TRACE    = 1,
    DEBUG    = 10,
    INFO     = 20,
    WARNING  = 30,
    ERROR    = 40,
    CRITICAL = 50
};

struct log_message
{
    log_level_t log_level;
    std::string component;
    std::string message;

    log_message(const log_level_t log_level_,
        const std::string& component_,
        const std::string& message_)
        : log_level(log_level_), component(component_), message(message_)
    {
        // nop
    }
};

class log_buf : public mpm::noncopyable
{
public:
    using sptr = std::shared_ptr<log_buf>;

    static const size_t BUFSIZE = 20;

    log_buf() : _buf(BUFSIZE) {}
    ~log_buf() {}

    static sptr make();

    static sptr make_singleton();

    /*! Post a message to the ring buffer
     *
     * \param log_level Log level
     * \param component The component where the message is originating from
     * \param message The actual log message
     */
    void post(const log_level_t log_level,
        const std::string& component,
        const std::string& message);

    //! Use this to set a callback that gets called when a new message was
    //  posted.
    void set_notify_callback(std::function<void(void)> callback);

    std::tuple<log_level_t, std::string, std::string> pop();

private:
    std::mutex _buf_lock;
    boost::circular_buffer<log_message> _buf;
    std::function<void(void)> _notify_callback;
};

}} /* namespace mpm::types */
