<?php

declare(strict_types=1);

class VGT_Sub extends IPSModule
{
    private bool $Subscribed = false;

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

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

        // 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 (read-only)
        $this->RegisterVariableInteger('PowerSetpoint', 'Power Setpoint', '', 20);
        $this->RegisterVariableString('Strategy', 'Strategy', '', 21);
        $this->RegisterVariableString('RemoteControlPayload', 'Remote Control Payload', '', 30);

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

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

        // Parent verbinden
        $this->ConnectParent('{C6D2AEB3-6E1F-4B2E-8E69-3A1A00246850}');

        // Subscribes erst, wenn Parent aktiv wird
        $this->Subscribed = false;

        // Statusänderungen überwachen
        $this->RegisterMessage($this->InstanceID, IM_CHANGESTATUS);

        $parent = @IPS_GetInstance($this->InstanceID)['ConnectionID'] ?? 0;
        if ($parent > 0 && IPS_InstanceExists($parent)) {
            $this->RegisterMessage($parent, IM_CHANGESTATUS);
        }
    }

    /* ---------------------------------------------------------
     * MESSAGE SINK – reagiert auf Parent-Aktivierung
     * ---------------------------------------------------------*/
    public function MessageSink($TimeStamp, $SenderID, $Message, $Data)
    {
        if ($Message !== IM_CHANGESTATUS) {
            return;
        }

        $new = $Data[0] ?? 0;

        // Eigene Instanz aktiv
        if ($SenderID === $this->InstanceID && $new === IS_ACTIVE) {
            $this->TrySubscribe();
        }

        // Parent aktiv
        $parent = @IPS_GetInstance($this->InstanceID)['ConnectionID'] ?? 0;
        if ($SenderID === $parent && $new === IS_ACTIVE) {
            $this->TrySubscribe();
        }
    }

    /* ---------------------------------------------------------
     * Prüfen ob Parent aktiv ist
     * ---------------------------------------------------------*/
    private function HasActiveParent(): bool
    {
        $parent = @IPS_GetInstance($this->InstanceID)['ConnectionID'] ?? 0;

        if ($parent === 0 || !IPS_InstanceExists($parent)) {
            return false;
        }
        return IPS_GetInstance($parent)['InstanceStatus'] === IS_ACTIVE;
    }

    /* ---------------------------------------------------------
     * Safe Sender – garantiert keine Fehler mehr
     * ---------------------------------------------------------*/
    private function SafeSendToParent(array $packet)
    {
        if (!$this->HasActiveParent()) {
            $this->SendDebug("MQTT", "Parent not active – send skipped", 0);
            return;
        }

        @ $this->SendDataToParent(json_encode($packet));
    }

    /* ---------------------------------------------------------
     * Subscribe (safe)
     * ---------------------------------------------------------*/
    private function TrySubscribe()
    {
        if ($this->Subscribed) {
            return;
        }

        $device = $this->ReadPropertyString('DeviceID');
        if ($device === '') {
            return;
        }

        $this->Subscribed = true;

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

    private function Subscribe(string $topic)
    {
        $this->SafeSendToParent([
            'DataID'           => '{043EA491-0325-4ADD-8FC2-A30C8EEB4D3F}',
            'PacketType'       => 8,
            'QualityOfService' => 0,
            'Retain'           => false,
            'Topic'            => $topic,
            'Payload'          => ''
        ]);
    }

    /* ---------------------------------------------------------
     * Publish (safe)
     * ---------------------------------------------------------*/
    private function Publish(string $topic, string $payload)
    {
        $this->SafeSendToParent([
            'DataID'           => '{043EA491-0325-4ADD-8FC2-A30C8EEB4D3F}',
            'PacketType'       => 3,
            'QualityOfService' => 0,
            'Retain'           => false,
            'Topic'            => $topic,
            'Payload'          => $payload
        ]);
    }

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

        $device = $this->ReadPropertyString('DeviceID');
        if ($device === '') {
            return;
        }

        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;
        }
    }

    /* ---------------------------------------------------------
     * ReceiveData
     * ---------------------------------------------------------*/
    public function ReceiveData($JSONString)
    {
        $this->TrySubscribe();

        $data = json_decode($JSONString, true);
        if (!is_array($data)) {
            return;
        }

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

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

        $device = $this->ReadPropertyString('DeviceID');
        if ($device === '') {
            return;
        }

        /* --- 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;
        }

        /* --- Remote Control Request --- */
        if ($topic === "remote-control-request/$device") {

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

            $json = json_decode($payload, true);
            if (is_array($json)) {
                if (isset($json['power_setpoint'])) {
                    $this->SetValue('PowerSetpoint', (int)$json['power_setpoint']);
                }
                if (isset($json['strategy'])) {
                    $this->SetValue('Strategy', (string)$json['strategy']);
                }
            }

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

?>