#pragma once

#include <QByteArray>
#include <QString>
#include <optional>

// Low-level, stateless helpers for the Apart Concept 1 RS-232 ASCII protocol.
//
// Port settings (fixed by the device): 19200 baud, 8 data bits, no parity,
// 1 stop bit, no flow control. Every instruction ends with <CR> (0x0D).
namespace Concept1 {

constexpr int kBaudRate = 19200;
constexpr char kCr = '\r';
constexpr char kLf = '\n';

// Volume levels: -79..0 dB, with -80 meaning "OFF".
constexpr int kLevelOff = -80;
constexpr int kLevelMin = -79;
constexpr int kLevelMax = 0;

// Equalizer (bass/treble): -14..14 in steps of 2.
constexpr int kEqMin = -14;
constexpr int kEqMax = 14;
constexpr int kEqStep = 2;

// Input gain: -20..14 in steps of 2.
constexpr int kGainMin = -20;
constexpr int kGainMax = 14;
constexpr int kGainStep = 2;

enum class Command { Set, Get, Inc, Dec };

enum class Zone { None, Zone1, Zone2 };

enum class Source { A, B, C, D };

// All attributes understood by the Concept 1.
enum class Attribute {
    MultiZone,
    ZoneLink,
    MusicLevel,    // MSCLVL
    MicLevel,      // MICLVL
    MaxMusicLevel, // MAXMSCLVL
    MaxMicLevel,   // MAXMICLVL
    Select,        // SELECT  A/B/C/D
    EqBass,        // EQBASS
    EqTreble,      // EQTREB
    Standby,       // STANDBY
    AutoLoudness,  // AUTOLD
    PagingActive,  // PAGACT
    InputGain,     // IPGAIN  (per source)
    Echo,          // ECHO
    LineFeed,      // LF
    BackSpace,     // BS
    Header,        // HEADER
    ValueFeedback, // VALFB
    Info,          // INFO  (GET only)
    SourceName,    // SOURCENAME (per source)
    Serial,        // SERIAL  (GET only)
    HwVersion,     // HWVRSN  (GET only)
    SwVersion,     // SWVRSN  (GET only)
    Restore,       // RESTORE (SET only)
    Unknown
};

// Classification of a line received from the device.
enum class ReplyKind {
    Value,        // an attribute value, e.g. "MSCLVL ZONE1 -16"
    Info,         // a single line of a GET INFO dump (also Value-shaped)
    Paging,       // "PAGING ZONEx ON/OFF" or "PAGING ON/OFF"
    Acknowledge,  // "Command Executed!" (also accepts the doc typo "Exicuted")
    PleaseCycle,  // "Please Cycle Power!"
    PowerDown,    // "POWER DOWN!"
    Standby,      // bare "STANDBY ON" sent while not ready
    Error,        // "ERROR: ...!"
    NotImplemented, // "Not Yet Implemented!"
    Echo,         // an echoed instruction (when ECHO is on)
    Unknown
};

struct ParsedReply {
    ReplyKind kind = ReplyKind::Unknown;
    Attribute attribute = Attribute::Unknown;
    Zone zone = Zone::None;
    std::optional<Source> source;
    QString rawText;       // full original line (trimmed)
    QString textValue;     // string value (source names, serial, versions, error text)
    std::optional<int> intValue; // numeric value where applicable (dB / eq / gain)
    bool boolValue = false;      // for ON/OFF attributes
    bool hasBool = false;        // whether boolValue is meaningful
};

// --- String mapping helpers ---------------------------------------------
QString attributeToken(Attribute attr);            // e.g. "MSCLVL"
Attribute attributeFromToken(const QString &token); // case-insensitive
QString commandToken(Command cmd);
QString zoneToken(Zone zone);                       // "ZONE1"/"ZONE2"/""
QString sourceToken(Source src);                    // "A".."D"
std::optional<Source> sourceFromToken(const QString &token);
std::optional<Zone> zoneFromToken(const QString &token);

// --- Value validation / normalisation -----------------------------------
int clampLevel(int value);          // -80..0
int normalizeEq(int value);         // snap to nearest valid -14..14/2
int normalizeGain(int value);       // snap to nearest valid -20..14/2
int clampStep(int step);            // 1..10
QString levelToDisplay(int level);  // "OFF" or "-16 dB"
QString levelToken(int level);      // "OFF" or "-16" (protocol wire form)

// --- Command building ----------------------------------------------------
// Builds a full instruction terminated with <CR>.
QByteArray buildCommand(Command cmd, Attribute attr,
                        Zone zone = Zone::None,
                        std::optional<Source> source = std::nullopt,
                        std::optional<QString> value = std::nullopt);

// Convenience builders.
QByteArray buildGet(Attribute attr, Zone zone = Zone::None,
                    std::optional<Source> source = std::nullopt);
QByteArray buildSetBool(Attribute attr, bool on, Zone zone = Zone::None);
QByteArray buildSetInt(Attribute attr, int value, Zone zone = Zone::None,
                       std::optional<Source> source = std::nullopt);
QByteArray buildSetString(Attribute attr, const QString &value,
                          std::optional<Source> source = std::nullopt);
QByteArray buildStep(Command incOrDec, Attribute attr, int step,
                     Zone zone = Zone::None);

// --- Reply parsing -------------------------------------------------------
// Parses a single line (without <CR>/<LF>) received from the device.
ParsedReply parseReply(const QString &line);

} // namespace Concept1