#使用IOTGW-NUC100构建智慧园区能源监测系统

// DDSU666电表数据解析
var regs = msg.payload;

// 高低位字节转换（DDSU666格式）
function parseU32(high, low) {
    return (low << 16) | high;
}
function parseS32(high, low) {
    var val = parseU32(high, low);
    if (val >= 0x80000000) {
        return val - 0x100000000;
    }
    return val;
}

var voltage = parseU32(regs[1], regs[0]) / 10;      // V
var current = parseU32(regs[3], regs[2]) / 100;      // A  
var power = parseS32(regs[5], regs[4]);              // W
var pf = parseU32(regs[9], regs[8]) / 1000;         // 功率因数
var energy = parseU32(regs[13], regs[12]);           // kWh

return {
    meter_id: "electric_01",
    timestamp: new Date().toISOString(),
    meter_type: "electricity",
    data: {
        voltage: voltage.toFixed(1),
        current: current.toFixed(2),
        power: power,
        power_factor: pf.toFixed(3),
        total_energy: energy,
        power_level: power > 0 ? "positive" : "reverse"
    }
};

// 超声波水表数据解析（示例）
var regs = msg.payload;

return {
    meter_id: "water_01",
    timestamp: new Date().toISOString(),
    meter_type: "water",
    data: {
        flow_rate: regs[0] / 100,           // m³/h
        total_flow: regs[2] / 1000,          // m³（累计）
        temperature: regs[4] / 10,           // °C
        pressure: regs[6] / 100,            // MPa
        battery_level: regs[8]              // %
    }
};

// 累计用电量差值计算
var current = msg.data.total_energy;
var last = context.get('last_energy') || current;
var consumption = current - last;
context.set('last_energy', current);

return {
    meter_id: msg.meter_id,
    timestamp: msg.timestamp,
    period: "hourly",
    consumption: consumption > 0 ? consumption : 0,  // kWh
    data: msg.data
};

// 根据时间段计算电费
var now = new Date();
var hour = now.getHours();

var price = 0;
var period = "";

if (hour >= 0 && hour < 6) {
    price = 0.3; period = "低谷";
} else if (hour >= 6 && hour < 8) {
    price = 0.6; period = "平段";
} else if (hour >= 8 && hour < 12) {
    price = 0.9; period = "高峰";
} else if (hour >= 12 && hour < 18) {
    price = 0.6; period = "平段";
} else if (hour >= 18 && hour < 21) {
    price = 0.9; period = "高峰";
} else {
    price = 0.6; period = "平段";
}

var consumption = msg.consumption;
var cost = consumption * price;

return {
    ...msg,
    billing: {
        period: period,
        unit_price: price,
        consumption: consumption,
        cost: cost.toFixed(2)
    }
};

// 检测用电异常（如非工作时间大功率）
var now = new Date();
var hour = now.getHours();
var dayOfWeek = now.getDay();

var isWorkingHour = hour >= 8 && hour < 18;
var isWeekday = dayOfWeek > 0 && dayOfWeek < 6;

var power = msg.data.power;

if (!isWorkingHour && power > 1000) {
    // 非工作时间功率超过1kW，可能存在异常
    return {
        alert: true,
        level: "warning",
        message: "非工作时间用电异常",
        power: power,
        expected_max: 500
    };
}

if (isWeekday && !isWorkingHour && power < 50) {
    // 工作日非工作时间功率过低，可能设备未关闭
    return {
        alert: true,
        level: "info",
        message: "建议检查下班后设备状态"
    };
}