// Node-RED function: Solar AC Mode Decision
const soc       = msg.soc;        // sensor.solax_battery_soc
const pvPower   = msg.pvPower;    // sensor.solax_pv_power_total (W)
const chargeRate= msg.chargeRate; // sensor.solax_battery_1_power_charge (W)
const hour      = new Date().getHours();
const nightMode = hour >= 21 || hour < 7;
const hardCutoff = 28; // Never go below this SOC

let mode, temp, fan;

if (nightMode || soc < hardCutoff) {
    mode = 'off'; temp = null; fan = null;
} else if (soc > 70 && chargeRate > 1500) {
    mode = 'cool'; temp = 22; fan = 'high';
} else if (soc > 50 && pvPower > 1500) {
    mode = 'cool'; temp = 24; fan = 'auto';
} else if (soc > 30 && pvPower > 500) {
    mode = 'cool'; temp = 26; fan = 'low';
} else {
    mode = 'off'; temp = null; fan = null;
}

// Sequential command execution with delays (critical!)
// Some AC integrations ignore simultaneous commands
msg.commands = [];
if (mode === 'off') {
    msg.commands.push({service:'climate.turn_off', target:'climate.living_room_ac'});
} else {
    msg.commands.push({service:'climate.set_hvac_mode', data:{hvac_mode: mode}});
    msg.commands.push({service:'climate.set_temperature', data:{temperature: temp}});
}

msg.modeLabel = mode === 'off' ? 'Off' : `${temp}°C / Fan ${fan}`;
return msg;

// Node-RED function: Biltong Absolute Humidity Delta
// Absolute humidity (g/m³) from relative humidity + temperature
function absHumidity(tempC, rhPercent) {
    const es = 6.112 * Math.exp((17.67 * tempC) / (tempC + 243.5));
    return (rhPercent / 100) * es * 2.1674 / (tempC + 273.15);
}

const inside_temp = parseFloat(msg.inside_temp) || 22;
const inside_rh   = parseFloat(msg.inside_rh) || 60;
const outside_temp= parseFloat(msg.outside_temp) || 20;
const outside_rh  = parseFloat(msg.outside_rh) || 55;

const inside_ah  = absHumidity(inside_temp, inside_rh);
const outside_ah = absHumidity(outside_temp, outside_rh);
const delta      = inside_ah - outside_ah;

// Drying is happening when delta is positive
// Peak delta = active drying phase
// Declining delta = near done
// Delta approaching 0 = done

const batchId   = flow.get('batch_id') || 'batch_001';
const startedAt = flow.get('batch_started') || Date.now();
const elapsedH  = (Date.now() - startedAt) / 3600000;

// Track peak delta for phase detection
const peakDelta = Math.max(flow.get('peak_delta') || 0, delta);
flow.set('peak_delta', peakDelta);

const phase = delta < 0.5 ? 'stabilising'
            : delta >= peakDelta * 0.9 ? 'active_drying'
            : delta >= peakDelta * 0.6 ? 'near_done'
            : 'done_window';

const csvRow = [
    new Date().toISOString(),   // timestamp
    batchId,                    // batch identifier
    inside_temp.toFixed(1),     // inside temp °C
    inside_rh.toFixed(1),       // inside RH %
    outside_temp.toFixed(1),    // outside temp °C
    outside_rh.toFixed(1),      // outside RH %
    inside_ah.toFixed(3),       // inside absolute humidity g/m³
    outside_ah.toFixed(3),      // outside absolute humidity g/m³
    delta.toFixed(3),           // delta (key metric)
    peakDelta.toFixed(3),       // running peak
    elapsedH.toFixed(2),        // hours elapsed
    phase,                      // current phase
    'auto'                      // entry type (auto vs manual)
].join(',');

msg.payload = csvRow + '\n';
msg.filename = `/homeassistant/www/biltong_batches/${batchId}.csv`;
msg.phase = phase;
return msg;

// Node-RED function: Sequential Zone Controller
// Called from inject (scheduled) or RF remote trigger
const zones = [
    { id: 'switch.zone_1_valve', name: 'Front Garden', minutes: 12 },
    { id: 'switch.zone_2_valve', name: 'Back Lawn',    minutes: 15 },
    { id: 'switch.zone_3_valve', name: 'Veggie Beds',  minutes: 8  },
];

// Safety checks before starting
const rainSensor  = msg.rain_today;   // boolean from weather integration
const pvPower     = msg.pv_power;     // W from solar integration
const soc         = msg.soc;          // % from battery

if (rainSensor) {
    node.warn('Skipping irrigation — rain detected');
    return null;
}

// Optional: only irrigate when solar excess available
// Comment out if you want scheduled irrigation regardless
if (pvPower < 500 && soc < 60) {
    node.warn('Skipping irrigation — insufficient solar');
    return null;
}

// Build sequential command list with delays
msg.commands = [];
zones.forEach((zone, i) => {
    // Turn on this zone
    msg.commands.push({
        type: 'service',
        service: 'switch.turn_on',
        entity_id: zone.id,
        delay_after: zone.minutes * 60 * 1000  // ms
    });
    // Turn off this zone before starting next
    msg.commands.push({
        type: 'service',
        service: 'switch.turn_off',
        entity_id: zone.id,
        delay_after: 2000  // 2s between zones
    });
});

msg.zone_count = zones.length;
msg.total_minutes = zones.reduce((sum, z) => sum + z.minutes, 0);
return msg;

// Node-RED function: Solar Diagnostic CSV Row Builder
// Dual-file architecture: master (append only) + buffer (cleared per session)
const now = new Date();

// Core inverter sensors (SolaX X1-Hybrid-G4)
const row = {
    timestamp:         now.toISOString(),
    date:              now.toLocaleDateString('en-ZA'),
    time:              now.toLocaleTimeString('en-ZA'),
    hour:              now.getHours(),
    minute:            now.getMinutes(),
    day_of_week:       now.getDay(),

    // PV Production
    pv_power_total:    msg.pv_power_total || 0,
    pv_power_string1:  msg.pv1_power || 0,
    pv_power_string2:  msg.pv2_power || 0,
    pv_voltage_1:      msg.pv1_voltage || 0,
    pv_voltage_2:      msg.pv2_voltage || 0,
    pv_current_1:      msg.pv1_current || 0,
    pv_current_2:      msg.pv2_current || 0,

    // Battery
    battery_soc:       msg.battery_soc || 0,
    battery_power:     msg.battery_power || 0,  // + = charge, - = discharge
    battery_charge_rate: msg.charge_rate || 0,
    battery_temp:      msg.battery_temp || 0,
    battery_voltage:   msg.battery_voltage || 0,

    // Grid
    grid_power:        msg.grid_power || 0,      // + = import, - = export
    grid_voltage:      msg.grid_voltage || 0,
    grid_frequency:    msg.grid_frequency || 0,

    // House consumption
    house_load:        msg.house_load || 0,
    inverter_mode:     msg.inverter_mode || 'unknown',

    // Today totals
    today_solar:       msg.today_solar || 0,
    today_import:      msg.today_import || 0,
    today_export:      msg.today_export || 0,
    today_consumption: msg.today_consumption || 0,

    // Environment
    outdoor_temp:      msg.outdoor_temp || 0,
    outdoor_humidity:  msg.outdoor_rh || 0,

    // Calculated
    self_consumption_pct: msg.pv_power_total > 0
        ? Math.min(100, ((msg.pv_power_total - Math.max(0, msg.grid_power * -1)) / msg.pv_power_total * 100)).toFixed(1)
        : 0,
};

const csvLine = Object.values(row).join(',') + '\n';

// Write to both files
msg.masterFile  = '/homeassistant/www/solar_master.csv';
msg.bufferFile  = '/homeassistant/www/solar_buffer.csv';
msg.payload     = csvLine;
return msg;

# HA Automation (YAML) — Solar production start/end detection
# Avoids the problem of sun.sun triggering automations at astronomical
# sunrise/sunset — which doesn't match when panels actually produce

automation:
  - alias: "Solar production started"
    trigger:
      - platform: numeric_state
        entity_id: sensor.solax_pv_power_total
        above: 50              # 50W threshold — avoids cloud flicker
        for: "00:10:00"        # Sustained for 10 minutes
    condition:
      - condition: time
        after: "06:00:00"      # Not before 6am
        before: "10:00:00"     # Not after 10am (not a midday recovery)
      - condition: state
        entity_id: input_boolean.solar_producing
        state: "off"           # Only fire once per day
    action:
      - service: input_boolean.turn_on
        entity_id: input_boolean.solar_producing
      - service: notify.mobile_app_your_phone
        data:
          message: >
            ☀️ Solar online: {{ states('sensor.solax_pv_power_total') }}W

  - alias: "Solar production ended"
    trigger:
      - platform: numeric_state
        entity_id: sensor.solax_pv_power_total
        below: 50
        for: "00:15:00"
    condition:
      - condition: time
        after: "14:00:00"      # After 2pm — genuine sunset, not cloud
      - condition: state
        entity_id: input_boolean.solar_producing
        state: "on"
    action:
      - service: input_boolean.turn_off
        entity_id: input_boolean.solar_producing
      - service: notify.mobile_app_your_phone
        data:
          message: >
            🌙 Solar offline. Today: {{ states('sensor.solax_today_s_solar_energy') }} kWh