#include "presets/PresetManager.h"

#include "pipewire/pipewirecontroller.h"
#include "gui/PipeWireGraphModel.h"

#include <QFile>
#include <QJsonArray>
#include <QJsonDocument>
#include <QVector>

#include <algorithm>

PresetManager::PresetManager(Potato::PipeWireController *controller,
                             PipeWireGraphModel *model,
                             QObject *parent)
    : QObject(parent)
    , m_controller(controller)
    , m_model(model)
{
}

bool PresetManager::savePreset(const QString &path) const
{
    if (!m_controller || !m_model || path.isEmpty()) {
        return false;
    }

    const QJsonObject root = buildPreset();
    const QJsonDocument doc(root);

    QFile file(path);
    if (!file.open(QIODevice::WriteOnly | QIODevice::Truncate)) {
        return false;
    }

    file.write(doc.toJson(QJsonDocument::Indented));
    return true;
}

bool PresetManager::loadPreset(const QString &path)
{
    if (!m_controller || !m_model || path.isEmpty()) {
        return false;
    }

    QFile file(path);
    if (!file.open(QIODevice::ReadOnly)) {
        return false;
    }

    const QJsonDocument doc = QJsonDocument::fromJson(file.readAll());
    if (!doc.isObject()) {
        return false;
    }

    return applyPreset(doc.object());
}

QJsonObject PresetManager::buildPreset() const
{
    QJsonObject root;
    root["version"] = QString("1.0");

    const QVector<Potato::NodeInfo> nodes = m_controller->nodes();
    QHash<uint32_t, Potato::NodeInfo> nodesById;
    for (const auto &node : nodes) {
        nodesById.insert(node.id, node);
    }

    QJsonArray virtualDevices;
    for (const auto &node : nodes) {
        if (node.type != Potato::NodeType::Virtual) {
            continue;
        }
        QJsonObject device;
        device["name"] = node.name;
        device["description"] = node.description;
        device["stable_id"] = node.stableId;
        const int channels = std::max(node.inputPorts.size(), node.outputPorts.size());
        device["channels"] = channels > 0 ? channels : 2;
        device["rate"] = 48000;
        device["media_class"] = mediaClassToString(node.mediaClass);
        virtualDevices.append(device);
    }
    root["virtual_devices"] = virtualDevices;

    QJsonArray routing;
    const QVector<Potato::LinkInfo> links = m_controller->links();
    for (const auto &link : links) {
        if (!nodesById.contains(link.outputNodeId) || !nodesById.contains(link.inputNodeId)) {
            continue;
        }
        const Potato::NodeInfo &outNode = nodesById.value(link.outputNodeId);
        const Potato::NodeInfo &inNode = nodesById.value(link.inputNodeId);

        QString outPortName;
        QString inPortName;
        if (!findPortName(outNode, link.outputPortId, outPortName)) {
            continue;
        }
        if (!findPortName(inNode, link.inputPortId, inPortName)) {
            continue;
        }

        QJsonObject route;
        route["source"] = QString("%1:%2").arg(outNode.stableId, outPortName);
        route["target"] = QString("%1:%2").arg(inNode.stableId, inPortName);
        route["volume"] = 1.0;
        route["muted"] = false;
        routing.append(route);
    }
    root["routing"] = routing;

    QJsonObject volumes;
    QJsonObject mutes;
    const QHash<QString, NodeVolumeState> volumeStates = m_model->volumeStates();
    for (auto it = volumeStates.cbegin(); it != volumeStates.cend(); ++it) {
        volumes[it.key()] = it.value().volume;
        mutes[it.key()] = it.value().mute;
    }
    root["persistent_volumes"] = volumes;
    root["persistent_mutes"] = mutes;

    root["ui_layout"] = m_model->layoutJson();

    return root;
}

bool PresetManager::applyPreset(const QJsonObject &root)
{
    const QVector<Potato::NodeInfo> nodes = m_controller->nodes();
    QHash<QString, Potato::NodeInfo> nodesByStableId;
    for (const auto &node : nodes) {
        if (!node.stableId.isEmpty()) {
            nodesByStableId.insert(node.stableId, node);
        }
    }

    const QJsonArray virtualDevices = root.value("virtual_devices").toArray();
    for (const auto &entry : virtualDevices) {
        const QJsonObject device = entry.toObject();
        const QString stableId = device.value("stable_id").toString();
        const QString name = device.value("name").toString();
        const QString description = device.value("description").toString();
        const QString mediaClassValue = device.value("media_class").toString();
        const int channels = device.value("channels").toInt(2);
        const int rate = device.value("rate").toInt(48000);

        if (!stableId.isEmpty() && nodesByStableId.contains(stableId)) {
            continue;
        }

        const Potato::MediaClass mediaClass = mediaClassFromString(mediaClassValue);
        if (mediaClass == Potato::MediaClass::AudioSource) {
            m_controller->createVirtualSource(name, description, channels, rate);
        } else {
            m_controller->createVirtualSink(name, description, channels, rate);
        }
    }

    const QJsonArray routing = root.value("routing").toArray();
    for (const auto &entry : routing) {
        const QJsonObject route = entry.toObject();
        const QString source = route.value("source").toString();
        const QString target = route.value("target").toString();

        uint32_t outNodeId = 0;
        uint32_t outPortId = 0;
        uint32_t inNodeId = 0;
        uint32_t inPortId = 0;

        if (!parsePortKey(source, outNodeId, outPortId)) {
            continue;
        }
        if (!parsePortKey(target, inNodeId, inPortId)) {
            continue;
        }

        m_controller->createLink(outNodeId, outPortId, inNodeId, inPortId);
    }

    QHash<QString, NodeVolumeState> volumeStates;
    const QJsonObject volumes = root.value("persistent_volumes").toObject();
    const QJsonObject mutes = root.value("persistent_mutes").toObject();
    for (auto it = volumes.begin(); it != volumes.end(); ++it) {
        NodeVolumeState state;
        state.volume = static_cast<float>(it.value().toDouble(1.0));
        state.mute = mutes.value(it.key()).toBool(false);
        volumeStates.insert(it.key(), state);
    }
    if (!volumeStates.isEmpty()) {
        m_model->applyVolumeStates(volumeStates);
    }

    const QJsonObject layout = root.value("ui_layout").toObject();
    if (!layout.isEmpty()) {
        m_model->applyLayoutJson(layout);
    }

    return true;
}

bool PresetManager::findPortName(const Potato::NodeInfo &node, uint32_t portId, QString &portName) const
{
    for (const auto &port : node.inputPorts) {
        if (port.id == portId) {
            portName = port.name;
            return true;
        }
    }
    for (const auto &port : node.outputPorts) {
        if (port.id == portId) {
            portName = port.name;
            return true;
        }
    }
    return false;
}

bool PresetManager::parsePortKey(const QString &key, uint32_t &nodeId, uint32_t &portId) const
{
    const int split = key.lastIndexOf(':');
    if (split <= 0) {
        return false;
    }

    const QString stableId = key.left(split);
    const QString portName = key.mid(split + 1);
    if (stableId.isEmpty() || portName.isEmpty()) {
        return false;
    }

    const QVector<Potato::NodeInfo> nodes = m_controller->nodes();
    for (const auto &node : nodes) {
        if (node.stableId != stableId) {
            continue;
        }
        for (const auto &port : node.inputPorts) {
            if (port.name == portName) {
                nodeId = node.id;
                portId = port.id;
                return true;
            }
        }
        for (const auto &port : node.outputPorts) {
            if (port.name == portName) {
                nodeId = node.id;
                portId = port.id;
                return true;
            }
        }
    }

    return false;
}

QString PresetManager::portKey(const Potato::NodeInfo &node, const Potato::PortInfo &port) const
{
    return QString("%1:%2").arg(node.stableId, port.name);
}

QString PresetManager::mediaClassToString(Potato::MediaClass mediaClass) const
{
    switch (mediaClass) {
    case Potato::MediaClass::AudioSink:
        return QString("Audio/Sink");
    case Potato::MediaClass::AudioSource:
        return QString("Audio/Source");
    case Potato::MediaClass::AudioDuplex:
        return QString("Audio/Duplex");
    case Potato::MediaClass::Stream:
        return QString("Stream");
    default:
        return QString();
    }
}

Potato::MediaClass PresetManager::mediaClassFromString(const QString &value) const
{
    if (value.contains("Audio/Source")) {
        return Potato::MediaClass::AudioSource;
    }
    if (value.contains("Audio/Duplex")) {
        return Potato::MediaClass::AudioDuplex;
    }
    if (value.contains("Audio/Sink")) {
        return Potato::MediaClass::AudioSink;
    }
    if (value.contains("Stream")) {
        return Potato::MediaClass::Stream;
    }
    return Potato::MediaClass::Unknown;
}