snapcast/server/streamreader/properties.hpp

/***
    This file is part of snapcast
    Copyright (C) 2014-2024  Johannes Pohl

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
***/

#pragma once


// local headers
#include "common/json.hpp"
#include "metadata.hpp"

// standard headers
#include <optional>
#include <string>


using json = nlohmann::json;

enum class PlaybackStatus
{
    kPlaying = 0,
    kPaused = 1,
    kStopped = 2,
    kUnknown = 3
};


enum class LoopStatus
{
    kNone = 0,
    kTrack = 1,
    kPlaylist = 2,
    kUnknown = 3
};


static std::string to_string(PlaybackStatus playback_status)
{
    switch (playback_status)
    {
        case PlaybackStatus::kPlaying:
            return "playing";
        case PlaybackStatus::kPaused:
            return "paused";
        case PlaybackStatus::kStopped:
            return "stopped";
        default:
            return "unknown";
    }
}


static std::ostream& operator<<(std::ostream& os, PlaybackStatus playback_status)
{
    os << to_string(playback_status);
    return os;
}


static PlaybackStatus playback_status_from_string(std::string& status)
{
    if (status == "playing")
        return PlaybackStatus::kPlaying;
    else if (status == "paused")
        return PlaybackStatus::kPaused;
    else if (status == "stopped")
        return PlaybackStatus::kStopped;
    else
        return PlaybackStatus::kUnknown;
}


static std::istream& operator>>(std::istream& is, PlaybackStatus& playback_status)
{
    std::string status;
    playback_status = PlaybackStatus::kUnknown;
    if (is >> status)
        playback_status = playback_status_from_string(status);
    else
        playback_status = PlaybackStatus::kUnknown;
    return is;
}


static std::string to_string(LoopStatus loop_status)
{
    switch (loop_status)
    {
        case LoopStatus::kNone:
            return "none";
        case LoopStatus::kTrack:
            return "track";
        case LoopStatus::kPlaylist:
            return "playlist";
        default:
            return "unknown";
    }
}


static std::ostream& operator<<(std::ostream& os, LoopStatus loop_status)
{
    os << to_string(loop_status);
    return os;
}


static LoopStatus loop_status_from_string(std::string& status)
{
    if (status == "none")
        return LoopStatus::kNone;
    else if (status == "track")
        return LoopStatus::kTrack;
    else if (status == "playlist")
        return LoopStatus::kPlaylist;
    else
        return LoopStatus::kUnknown;
}


static std::istream& operator>>(std::istream& is, LoopStatus& loop_status)
{
    std::string status;
    if (is >> status)
        loop_status = loop_status_from_string(status);
    else
        loop_status = LoopStatus::kUnknown;

    return is;
}


class Properties
{
public:
    Properties() = default;
    Properties(const json& j);

    /// Meta data
    std::optional<Metadata> metadata;
    /// https://www.musicpd.org/doc/html/protocol.html#tags
    /// The current playback status
    std::optional<PlaybackStatus> playback_status;
    /// The current loop / repeat status
    std::optional<LoopStatus> loop_status;
    /// The current playback rate
    std::optional<float> rate;
    /// A value of false indicates that playback is progressing linearly through a playlist, while true means playback is progressing through a playlist in some
    /// other order.
    std::optional<bool> shuffle;
    /// The volume level between 0-100
    std::optional<int> volume;
    /// The current mute state
    std::optional<bool> mute;
    /// The current track position in seconds
    std::optional<float> position;
    /// The minimum value which the Rate property can take. Clients should not attempt to set the Rate property below this value
    std::optional<float> minimum_rate;
    /// The maximum value which the Rate property can take. Clients should not attempt to set the Rate property above this value
    std::optional<float> maximum_rate;
    /// Whether the client can call the next method on this interface and expect the current track to change
    bool can_go_next = false;
    /// Whether the client can call the previous method on this interface and expect the current track to change
    bool can_go_previous = false;
    /// Whether playback can be started using "play" or "playPause"
    bool can_play = false;
    /// Whether playback can be paused using "pause" or "playPause"
    bool can_pause = false;
    /// Whether the client can control the playback position using "seek" and "setPosition". This may be different for different tracks
    bool can_seek = false;
    /// Whether the media player may be controlled over this interface
    bool can_control = false;

    json toJson() const;
    void fromJson(const json& j);
    bool operator==(const Properties& other) const;
};