#!/bin/bash
#
# MQTT Discovery for Parallel Inverters
# Registers Home Assistant auto-discovery topics for each parallel inverter

MQTT_CONFIG="/etc/inverter/mqtt.json"
INVERTER_BIN="/opt/inverter-cli/bin/inverter_poller"

MQTT_SERVER=$(jq -r '.server' "$MQTT_CONFIG")
MQTT_PORT=$(jq -r '.port' "$MQTT_CONFIG")
MQTT_TOPIC=$(jq -r '.topic' "$MQTT_CONFIG")
MQTT_DEVICENAME=$(jq -r '.devicename' "$MQTT_CONFIG")
MQTT_USERNAME=$(jq -r '.username' "$MQTT_CONFIG")
MQTT_PASSWORD=$(jq -r '.password' "$MQTT_CONFIG")
MQTT_CLIENTID=$(jq -r '.clientid' "$MQTT_CONFIG")

registerTopic () {
    local inverter_id="$1"
    local metric="$2"
    local unit="$3"
    local icon="$4"
    
    local device_name="${MQTT_DEVICENAME}_inv${inverter_id}"
    
    mosquitto_pub \
        -h $MQTT_SERVER \
        -p $MQTT_PORT \
        -u "$MQTT_USERNAME" \
        -P "$MQTT_PASSWORD" \
        -i "${MQTT_CLIENTID}_init" \
        -t "$MQTT_TOPIC/sensor/${device_name}_${metric}/config" \
        -r \
        -m "{
            \"name\": \"${device_name}_${metric}\",
            \"unit_of_measurement\": \"$unit\",
            \"state_topic\": \"$MQTT_TOPIC/sensor/${device_name}_${metric}\",
            \"icon\": \"mdi:$icon\",
            \"unique_id\": \"${device_name}_${metric}\",
            \"device\": {
                \"identifiers\": [\"${device_name}\"],
                \"name\": \"${device_name}\",
                \"manufacturer\": \"Voltronic\",
                \"model\": \"Parallel Inverter\"
            }
        }"
}

register_inverter_topics() {
    local inverter_id="$1"
    
    echo "Registering MQTT discovery topics for: ${MQTT_DEVICENAME}_inv${inverter_id}"
    
    # Register all metrics for this inverter
    registerTopic "$inverter_id" "serial" "" "identifier"
    registerTopic "$inverter_id" "mode" "" "solar-power"
    registerTopic "$inverter_id" "AC_grid_voltage" "V" "power-plug"
    registerTopic "$inverter_id" "AC_grid_frequency" "Hz" "current-ac"
    registerTopic "$inverter_id" "AC_out_voltage" "V" "power-plug"
    registerTopic "$inverter_id" "AC_out_frequency" "Hz" "current-ac"
    registerTopic "$inverter_id" "PV_in_voltage" "V" "solar-panel-large"
    registerTopic "$inverter_id" "PV_in_current" "A" "solar-panel-large"
    registerTopic "$inverter_id" "PV_in_watts" "W" "solar-panel-large"
    registerTopic "$inverter_id" "Load_pct" "%" "brightness-percent"
    registerTopic "$inverter_id" "Load_watt" "W" "chart-bell-curve"
    registerTopic "$inverter_id" "Load_va" "VA" "chart-bell-curve"
    registerTopic "$inverter_id" "Battery_capacity" "%" "battery-outline"
    registerTopic "$inverter_id" "Battery_voltage" "V" "battery-outline"
    registerTopic "$inverter_id" "Battery_charge_current" "A" "current-dc"
    
    echo "  ✓ Discovery topics registered"
}

# Discover parallel inverters
PARALLEL_DISCOVERY=$("$INVERTER_BIN" -p 2>&1)
PARALLEL_COUNT=$(echo "$PARALLEL_DISCOVERY" | grep "PARALLEL_COUNT=" | cut -d= -f2)

if [ -z "$PARALLEL_COUNT" ] || [ "$PARALLEL_COUNT" -eq 0 ]; then
    echo "No parallel inverters found, falling back to standard init"
    exec /opt/inverter-mqtt/mqtt-init.sh
    exit 0
fi

echo "Found $PARALLEL_COUNT parallel inverters"

# Register topics for each inverter
for i in $(seq 1 $PARALLEL_COUNT); do
    register_inverter_topics "$i"
done

echo "✓ All MQTT discovery topics registered for $PARALLEL_COUNT inverters"