<?php

declare(strict_types=1);

class VGT_Sub extends IPSModule
{
    public function Create()
    {
        parent::Create();

        // Konfiguration
        $this->RegisterPropertyString('DeviceID', '');

        // Auf Parent-Connect reagieren (für Re-Subscribe)
        $this->RegisterMessage($this->InstanceID, FM_CONNECT);

        /** -------------------------------------------
         *  STATUS Variablen (schreibbar)
         * ------------------------------------------*/

        $this->RegisterVariableInteger('PowerProduction', 'Power Production', '', 10);
        $this->EnableAction('PowerProduction');

        $this->RegisterVariableBoolean('IsReady', 'Is Ready', '', 11);
        $this->EnableAction('IsReady');

        $this->RegisterVariableBoolean('IsRunning', 'Is Running', '', 12);
        $this->EnableAction('IsRunning');

        $this->RegisterVariableInteger('StateOfCharge', 'State of Charge', '', 13);
        $this->EnableAction('StateOfCharge');

        $this->RegisterVariableInteger('MinSOC', 'Min SOC', '', 14);
        $this->EnableAction('MinSOC');

        $this->RegisterVariableInteger('MaxSOC', 'Max SOC', '', 15);
        $this->EnableAction('MaxSOC');


        /** -------------------------------------------
         *  REMOTE CONTROL Variablen (read-only)
         * ------------------------------------------*/

        $this->RegisterVariableInteger('PowerSetpoint', 'Power Setpoint', '', 20);
        $this->RegisterVariableString('Strategy', 'Strategy', '', 21);

        // Debug
        $this->RegisterVariableString('RemoteControlPayload', 'Remote Control Payload', '', 30);


        /** -------------------------------------------
         *  FEEDBACK REQUEST Variablen (read-only)
         * ------------------------------------------*/
        $this->RegisterVariableString('FeedbackRequestPayload', 'Feedback Request Payload', '', 40);
    }


    public function ApplyChanges()
    {
        parent::ApplyChanges();

        // Nach Konfigänderung Topics abonnieren
        if ($this->HasActiveParent()) {
            $this->SubscribeAll();
        }
    }

    /**
     * Reaktion auf Systemnachrichten (z.B. Parent verbindet sich)
     */
    public function MessageSink($TimeStamp, $SenderID, $Message, $Data)
    {
        parent::MessageSink($TimeStamp, $SenderID, $Message, $Data);

        switch ($Message) {
            case FM_CONNECT:
                // Parent (MQTT-Client) hat Verbindung aufgebaut -> erneut subscriben
                if ($this->HasActiveParent()) {
                    $this->SendDebug('MQTT', 'FM_CONNECT -> Re-Subscribe Topics', 0);
                    $this->SubscribeAll();
                }
                break;
        }
    }

    /**
     * Alle benötigten Topics abonnieren
     */
    private function SubscribeAll(): void
    {
        $device = $this->ReadPropertyString('DeviceID');
        if ($device === '') {
            $this->SendDebug('MQTT', 'Kein DeviceID gesetzt, keine Subscribes', 0);
            return;
        }

        $this->Subscribe("feedback-request/$device");
        $this->Subscribe("remote-control-request/$device");
    }


    /** -------------------------------------------
     *  VARIABLE WRITE SUPPORT
     * ------------------------------------------*/
    public function RequestAction($Ident, $Value)
    {
        $this->SetValue($Ident, $Value);

        $device = $this->ReadPropertyString('DeviceID');
        if ($device !== '') {
            switch ($Ident) {
                case 'PowerProduction':
                case 'IsReady':
                case 'IsRunning':
                case 'StateOfCharge':
                case 'MinSOC':
                case 'MaxSOC':
                    $payload = json_encode([
                        'power_production' => $this->GetValue('PowerProduction'),
                        'is_ready'         => $this->GetValue('IsReady'),
                        'is_running'       => $this->GetValue('IsRunning'),
                        'state_of_charge'  => $this->GetValue('StateOfCharge'),
                        'min_soc'          => $this->GetValue('MinSOC'),
                        'max_soc'          => $this->GetValue('MaxSOC')
                    ]);
                    $this->Publish("status/$device", $payload);
                    break;
            }
        }
    }


    /** -------------------------------------------
     *  MQTT SUBSCRIBE
     * ------------------------------------------*/
    private function Subscribe(string $topic): void
    {
        if (!$this->HasActiveParent()) {
            $this->SendDebug('MQTT', 'Subscribe ohne aktiven Parent: ' . $topic, 0);
            return;
        }

        $packet = [
            'PacketType'       => 8,   // SUBSCRIBE
            'QualityOfService' => 0,
            'Retain'           => false,
            'Topic'            => $topic,
            'Payload'          => ''
        ];

        $this->SendDebug('MQTT', 'Subscribe Topic=' . $topic, 0);

        $this->SendDataToParent(json_encode([
            'DataID' => '{043EA491-0325-4ADD-8FC2-A30C8EEB4D3F}'
        ] + $packet));
    }


    /** -------------------------------------------
     *  MQTT PUBLISH
     * ------------------------------------------*/
    private function Publish(string $topic, string $payload): void
    {
        if (!$this->HasActiveParent()) {
            $this->SendDebug('MQTT', 'Publish ohne aktiven Parent: ' . $topic, 0);
            return;
        }

        $packet = [
            'PacketType'       => 3,   // PUBLISH
            'QualityOfService' => 0,
            'Retain'           => false,
            'Topic'            => $topic,
            'Payload'          => $payload
        ];

        $this->SendDebug('MQTT', 'Publish Topic=' . $topic . ' Payload=' . $payload, 0);

        $this->SendDataToParent(json_encode([
            'DataID' => '{043EA491-0325-4ADD-8FC2-A30C8EEB4D3F}'
        ] + $packet));
    }


    /** -------------------------------------------
     *  RECEIVE DATA
     * ------------------------------------------*/
    public function ReceiveData($JSONString)
    {
        // Äußeres JSON vom MQTT-Client
        $data = json_decode($JSONString);
        if ($data === null) {
            $this->SendDebug('MQTT', 'Ungültiges JSON: ' . $JSONString, 0);
            return;
        }

        // Neuere MQTT-Client-Version: Topic/Payload stecken in Buffer als JSON-String
        if (isset($data->Buffer)) {
            $buffer = json_decode($data->Buffer, true);
        } else {
            // Fallback: evtl. altes Format
            $buffer = json_decode($JSONString, true);
        }

        if (!is_array($buffer)) {
            $this->SendDebug('MQTT', 'Buffer ist kein Array: ' . print_r($buffer, true), 0);
            return;
        }

        $topic   = $buffer['Topic']   ?? '';
        $payload = $buffer['Payload'] ?? '';

        $this->SendDebug('MQTT', 'Receive: Topic=' . $topic . ' Payload=' . $payload, 0);

        $device = $this->ReadPropertyString('DeviceID');
        if ($device === '') {
            $this->SendDebug('MQTT', 'Keine DeviceID gesetzt, ignoriere Receive', 0);
            return;
        }

        /** -------------------------------------------
         * 1️⃣ FEEDBACK REQUEST
         * ------------------------------------------*/
        if ($topic === "feedback-request/$device") {

            $this->SetValue('FeedbackRequestPayload', $payload);

            $json = json_decode($payload, true);
            if (!is_array($json)) {
                $json = [];
            }

            $response = array_merge($json, [
                "power_production" => $this->GetValue('PowerProduction'),
                "is_ready"         => $this->GetValue('IsReady'),
                "is_running"       => $this->GetValue('IsRunning'),
                "state_of_charge"  => $this->GetValue('StateOfCharge'),
                "min_soc"          => $this->GetValue('MinSOC'),
                "max_soc"          => $this->GetValue('MaxSOC')
            ]);

            $this->Publish("feedback-response/$device", json_encode($response));
            return;
        }

        /** -------------------------------------------
         * 2️⃣ REMOTE CONTROL REQUEST
         * ------------------------------------------*/
        if ($topic === "remote-control-request/$device") {

            $this->SetValue('RemoteControlPayload', $payload);

            $json = json_decode($payload, true);
            if (is_array($json)) {

                if (array_key_exists('power_setpoint', $json)) {
                    $this->SetValue('PowerSetpoint', (int)$json['power_setpoint']);
                }

                if (array_key_exists('strategy', $json)) {
                    $this->SetValue('Strategy', (string)$json['strategy']);
                }
            }

            $this->Publish("remote-control-response/$device", $payload);
            return;
        }
    }
}