const EventEmitter = require('events');
const {logger,configUtils,configManager,childRegistrationUtils,MeasurementContainer,coolprop,interpolation} = require('generalFunctions');

class pumpingStation {
  constructor(config={}) {

    this.emitter = new EventEmitter();  // Own EventEmitter
    this.configManager = new configManager(); 
    this.defaultConfig = this.configManager.getConfig('pumpingStation');
    this.configUtils = new configUtils(this.defaultConfig);
    this.config = this.configUtils.initConfig(config);
    this.interpolate = new interpolation();

    // Init after config is set
    this.logger = new logger(this.config.general.logging.enabled,this.config.general.logging.logLevel, this.config.general.name);

    // General properties
    this.measurements = new MeasurementContainer({
      autoConvert: true
    });

    // init basin object in pumping station
    this.basin = {};
    this.state = { direction:"", netDownstream:0, netUpstream:0, seconds:0}; // init state object of pumping station to see whats going on

    // Initialize basin-specific properties and calculate used parameters
    this.initBasinProperties();
    this.parent = {}; // object to hold parent information for when we follow flow directions.
    this.child = {}; // object to hold child information so we know on what to subscribe
    this.machines = {}; // object to hold child machine information
    this.childRegistrationUtils = new childRegistrationUtils(this); // Child registration utility

    this.logger.debug('pumpstation Initialized with all helpers');
  }

    /*-------------------               Register child events               -------------------*/
  registerChild(child, softwareType) {
    this.logger.debug('Setting up child event for softwaretype ' + softwareType);

    //define what to do with measurements
    if(softwareType === "measurement"){
          const position = child.config.functionality.positionVsParent;
          const distance = child.config.functionality.distanceVsParent || 0;
          const measurementType = child.config.asset.type;
          const key = `${measurementType}_${position}`;
          //rebuild to measurementype.variant no position and then switch based on values not strings or names.
          const eventName = `${measurementType}.measured.${position}`;

          this.logger.debug(`Setting up listener for ${eventName} from child ${child.config.general.name}`);
          // Register event listener for measurement updates
          child.measurements.emitter.on(eventName, (eventData) => {
          this.logger.debug(`🔄 ${position} ${measurementType} from ${eventData.childName}: ${eventData.value} ${eventData.unit}`);
      
          this.logger.debug(` Emitting... ${eventName} with data:`);
          // Store directly in parent's measurement container
          this.measurements.type(measurementType).variant("measured").position(position).value(eventData.value, eventData.timestamp, eventData.unit);
          
          // Call the appropriate handler
          this._callMeasurementHandler(measurementType, eventData.value, position, eventData);
      });
    }

    //define what to do when machines are connected
    if(softwareType == "machine"){
           // Check if the machine is already registered
           this.machines[child.config.general.id] === undefined ?  this.machines[child.config.general.id] = child : this.logger.warn(`Machine ${child.config.general.id} is already registered.`);
           
           //listen for machine pressure changes
           this.logger.debug(`Listening for flow changes from machine ${child.config.general.id}`);

           //for now lets focus on handling downstream predicted flow
          child.measurements.emitter.on("flow.predicted.downstream", (eventData) => {
                this.logger.debug(`Flow prediction update from ${child.config.general.id}: ${eventData.value} ${eventData.unit}`);
                this.measurements.type('flow').variant('predicted').position('atEquipment').value(eventData.value,eventData.timestamp,eventData.unit);
           });
      }

      // add one for group later
      if( softwareType == "machineGroup" ){

      }

  }

  //update prediction in outgoing downstream flow
  _updateDownstreamFlowPrediction(){

    //get downflow
    const downFlowExists = this.measurements.type("flow").variant("predicted").position("atEquipment").exists();
    if(!downFlowExists){return};

    const downFlow = this.measurements.type("flow").variant("predicted").position("atEquipment");
    const currDownFlow = downFlow.getLaggedValue(0, "m3/s"); // { value, timestamp, unit }
    const prevDownFlow = downFlow.getLaggedValue(1, "m3/s"); // { value, timestamp, unit }

    if (!currDownFlow || !prevDownFlow) return;

    this.logger.debug(`currDownflow = ${currDownFlow.value} , prevDownFlow = ${prevDownFlow.value}`);

    // calc difference in time 
    const deltaT = currDownFlow.timestamp - prevDownFlow.timestamp;
    const deltaSeconds = deltaT / 1000;

    if (deltaSeconds <= 0) {
      this.logger.warn(`Flow integration aborted; invalid Δt=${deltaSeconds}s.`);
      return;
    }

    const avgFlow = (currDownFlow.value + prevDownFlow.value) / 2;
    const volumeSubstracted = avgFlow * deltaSeconds;

    //substract seeing as this is downstream and is being pulled away from the pumpingstaion and keep track of status
    const currVolume = this.measurements.type('volume').variant('predicted').position('atEquipment').getCurrentValue('m3');
    const newVol = currVolume - volumeSubstracted;

    this.measurements.type('volume').variant('predicted').position('atEquipment').value(newVol).unit('m3');
    //convert to a predicted level
    const newLevel = this._calcLevelFromVolume(newVol);

    this.measurements.type('level').variant('predicted').position('atEquipment').value(newLevel).unit('m');

    this.logger.debug(`new predicted volume : ${newVol} new predicted level: ${newLevel} `);

  }

  //update prediction in incomming upstream flow
  _updateUpstreamFlowPrediction(){

  }
  //trigger shutdown when level is too low and trigger no start flag for childs ? 
  safetyVolCheck(){

  }


  //update measured temperature to adjust density of liquid
  updateMeasuredTemperature(){

  }

  //update measured flow and recalc 
  updateMeasuredFlow(){

  }

  //keep updating the volume / level when the flow is still active from a machine or machinegroup or incoming from another source
  tick(){
    //go through all the functions that require time based checks or updates
    this._updateDownstreamFlowPrediction();
  }
  

  _callMeasurementHandler(measurementType, value, position, context) {
  switch (measurementType) {
    case 'pressure':
      this.updateMeasuredPressure(value, position, context);
      break;
      
    case 'flow':
      this.updateMeasuredFlow(value, position, context);
      break;
      
    case 'temperature':
      this.updateMeasuredTemperature(value, position, context);
      break;

    case 'level':
      this.updateMeasuredLevel(value, position, context);
      break;
      
    default:
      this.logger.warn(`No handler for measurement type: ${measurementType}`);
      // Generic handler - just update position
      this.updatePosition();
      break;
  }
  }

  //  context handler for pressure updates
  updateMeasuredPressure(value, position, context = {}) {
   
    // init temp
    let kelvinTemp = null;

    //pressure updates come from pressure boxes inside the basin they get converted to a level and stored as level measured at position inlet or outlet
    this.logger.debug(`Pressure update: ${value} at ${position} from ${context.childName || 'child'} (${context.childId || 'unknown-id'})`);
    
    //  Store in parent's measurement container for the first time
    this.measurements.type("pressure").variant("measured").position(position).value(value, context.timestamp, context.unit);

    //convert pressure to level based on density of water and height of pressure sensor
    const mTemp = this.measurements.type("temperature").variant("measured").position("atEquipment").getCurrentValue('K'); //default to 20C if no temperature measurement

    //prefer measured temp but otherwise assume nominal temp for wastewater
    if(mTemp === null){
      this.logger.warn(`No temperature measurement available, defaulting to 15C for pressure to level conversion.`);
      this.measurements.type("temperature").variant("assumed").position("atEquipment").value(15, Date.now(), "C");
      kelvinTemp = this.measurements.type('temperature').variant('assumed').position('atEquipment').getCurrentValue('K');
      this.logger.debug(`Temperature is : ${kelvinTemp}`);
    } else {
      kelvinTemp = mTemp;
    }
    this.logger.debug(`Using temperature: ${kelvinTemp} K for calculations`);
    const density = coolprop.PropsSI('D','T',kelvinTemp,'P',101325,'Water'); //density in kg/m3 at temp and surface pressure
    const g = 9.80665;
    const pressure_Pa = this.measurements.type("pressure").variant("measured").position(position).getCurrentValue('Pa');
    const level = pressure_Pa / density * g;

    this.measurements.type("level").variant("predicted").position(position).value(level);
    //updatePredictedLevel(); ?? OLIFANT!

    //calculate how muc flow went in or out based on pressure difference
    this.logger.debug(`Using pressure: ${value} for calculations`);
    
  }

  updateMeasuredLevel(value,position, context = {}){
     //  Store in parent's measurement container for the first time
    this.measurements.type("level").variant("measured").position(position).value(value, context.timestamp, context.unit);

    //fetch level in meter 
    const level = this.measurements.type("level").variant("measured").position(position).getCurrentValue('m');
    //calc vol in m3
    const volume = this._calcVolumeFromLevel(level);
    this.logger.debug(`basin minvol : ${this.basin.minVol}, cur volume : ${volume} / ${this.basin.maxVolOverflow}`);

    const proc = this.interpolate.interpolate_lin_single_point(volume,this.basin.minVol,this.basin.maxVolOverflow,0,100);
    this.logger.debug(`PROC volume : ${proc}`);
    this.measurements.type("volume").variant("measured").position("atEquipment").value(volume).unit('m3');
    this.measurements.type("volume").variant("procent").position("atEquipment").value(proc);
    

    //calc the most important values back to determine state and net up or downstream flow
    this._calcNetFlow();
    
  }

  _calcNetFlow() {
    const { heightOverflow, heightOutlet, surfaceArea } = this.basin;

    const flowBased = this._calcNetFlowFromMeasurements({
      heightOverflow,
      heightOutlet,
      surfaceArea
    });

    const levelBased = this._calcNetFlowFromLevel({
      heightOverflow,
      heightOutlet,
      surfaceArea
    });

    if (flowBased && levelBased) {
      this.logger.debug(
        `Flow vs Level comparison | flow=${flowBased.netFlowRate.value.toFixed(3)} ` +
        `m3/s, level=${levelBased.netFlowRate.toFixed(3)} m3/s`
      );
    }

    const effective = flowBased || levelBased;
    if (effective) {
      this.state = effective.state;
      this.state.netFlowSource = flowBased ? (levelBased ? "flow+level" : "flow") : "level";
      this.logger.debug(`Net-flow state: ${JSON.stringify(this.state)}`);
    } else {
      this.logger.debug("Net-flow state: insufficient data");
    }

    return effective;
  }

  _calcNetFlowFromMeasurements({ heightOverflow, heightOutlet, surfaceArea }) {

    const flowDiff = this.measurements.type("flow").variant("measured").difference({ from: "downstream", to: "upstream", unit: "m3/s" });
    const level = this.measurements.type("level").variant("measured").position("atEquipment").getCurrentValue("m");
    const flowUpstream = this.measurements.type("flow").variant("measured").position("upstream").getCurrentValue("m3/s");
    const flowDownstream = this.measurements.type("flow").variant("measured").position("downstream").getCurrentValue("m3/s");

    if (flowDiff === null || level === null) {
      this.logger.warn(`no flowdiff ${flowDiff} or level ${level} found escaping`);
      return null;
    }

    const flowThreshold = 0.1; // m³/s
    const state = { direction: "stable", seconds: 0, netUpstream: flowUpstream ?? 0, netDownstream: flowDownstream ?? 0 };

    if (flowDiff > flowThreshold) {
      state.direction = "filling";
      const remainingHeight = Math.max(heightOverflow - level, 0);
      state.seconds = remainingHeight * surfaceArea / flowDiff;
    } else if (flowDiff < -flowThreshold) {
      state.direction = "draining";
      const remainingHeight = Math.max(level - heightOutlet, 0);
      state.seconds = remainingHeight * surfaceArea / Math.abs(flowDiff);
    }

    this.measurements.type("netFlowRate").variant("predicted").position("atEquipment").value(flowDiff).unit("m3/s");

    this.logger.debug(
      `Flow-based net flow | diff=${flowDiff.value.toFixed(3)} m3/s, level=${level.toFixed(3)} m`
    );

    return { source: "flow", netFlowRate: flowDiff, state };
  }

  _calcNetFlowFromLevel({ heightOverflow, heightOutlet, surfaceArea }) {
    const levelObj = this.measurements.type("level").variant("measured").position("atEquipment");
    const level = levelObj.getCurrentValue("m");
    const prevLevel = levelObj.getLaggedValue(2, "m"); // { value, timestamp, unit }
    const measurement = levelObj.get();
    const latestTimestamp = measurement?.getLatestTimestamp();

    if (level === null || !prevLevel || latestTimestamp == null) {
      this.logger.warn(`no flowdiff ${level}, previous level ${prevLevel}, latestTimestamp ${latestTimestamp} found escaping`);
      return null;
    }

    const deltaSeconds = (latestTimestamp - prevLevel.timestamp) / 1000;
    if (deltaSeconds <= 0) {
      this.logger.warn(`Level fallback: invalid Δt=${deltaSeconds} , LatestTimestamp : ${latestTimestamp}, PrevTimestamp : ${prevLevel.timestamp}`);
      return null;
    }

    const lvlDiff = level - prevLevel.value;
    const lvlRate = lvlDiff / deltaSeconds; // m/s
    const levelRateThreshold = 0.1 / surfaceArea; // same 0.1 m³/s threshold translated to height

    const state = { direction: "stable", seconds: 0, netUpstream: 0, netDownstream: 0 };

    if (lvlRate > levelRateThreshold) {
      state.direction = "filling";
      const remainingHeight = Math.max(heightOverflow - level, 0);
      state.seconds = remainingHeight / lvlRate;
    } else if (lvlRate < -levelRateThreshold) {
      state.direction = "draining";
      const remainingHeight = Math.max(level - heightOutlet, 0);
      state.seconds = remainingHeight / Math.abs(lvlRate);
    }

    const netFlowRate = lvlRate * surfaceArea; // m³/s inferred from level trend

    this.measurements.type("netFlowRate").variant("predicted").position("atEquipment").value(netFlowRate).unit("m3/s");

    this.logger.warn(
      `Level-based net flow | rate=${lvlRate.toExponential(3)} m/s, inferred=${netFlowRate.toFixed(3)} m3/s`
    );

    return { source: "level", netFlowRate, state };
  }

  initBasinProperties() {
    
    // Load and calc basic params
    const volEmptyBasin      = this.config.basin.volume;
    const heightBasin        = this.config.basin.height;
    const heightInlet        = this.config.basin.heightInlet;      
    const heightOutlet       = this.config.basin.heightOutlet;  
    const heightOverflow     = this.config.basin.heightOverflow;

    //calculated params
    const surfaceArea       = volEmptyBasin / heightBasin;
    const maxVol            = heightBasin * surfaceArea; // if Basin where to ever fill up completely this is the water volume
    const maxVolOverflow    = heightOverflow * surfaceArea ; // Max water volume before you start loosing water to overflow
    const minVol            = heightOutlet * surfaceArea;
    const minVolOut         = heightInlet * surfaceArea ; // this will indicate if its an open end or a closed end.

    this.basin.volEmptyBasin  = volEmptyBasin  ;
    this.basin.heightBasin    = heightBasin    ;
    this.basin.heightInlet    = heightInlet    ;
    this.basin.heightOutlet   = heightOutlet   ;
    this.basin.heightOverflow = heightOverflow ;
    this.basin.surfaceArea    = surfaceArea   ;
    this.basin.maxVol         = maxVol        ;
    this.basin.maxVolOverflow = maxVolOverflow;
    this.basin.minVol         = minVol        ;
    this.basin.minVolOut      = minVolOut     ;

    //init predicted min volume to min vol in order to have a starting point
    this.measurements.type("volume").variant("predicted").position("atEquipment").value(minVol).unit('m3');

    this.logger.debug(`
        Basin initialized | area=${surfaceArea.toFixed(2)} m², 
        max=${maxVol.toFixed(2)} m³, 
        overflow=${maxVolOverflow.toFixed(2)} m³`
    );


  }

_calcVolumeFromLevel(level) {
  const surfaceArea = this.basin.surfaceArea;
  return Math.max(level, 0) * surfaceArea;
}

_calcLevelFromVolume(vol){
  const surfaceArea = this.basin.surfaceArea;
  return Math.max(vol, 0) / surfaceArea;
}


  getOutput() {
    return {
      volume_m3: this.measurements.type("volume").variant("measured").position("atEquipment").getCurrentValue('m3') ,

    };
  }
}

module.exports = pumpingStation;

/* ------------------------------------------------------------------------- */
/* Example: pumping station + rotating machine + measurements (stand-alone)  */
/* ------------------------------------------------------------------------- */

const PumpingStation = require("./specificClass");
const RotatingMachine = require("../../rotatingMachine/src/specificClass");
const Measurement = require("../../measurement/src/specificClass");

/** Helpers ******************************************************************/
function createPumpingStationConfig(name) {
  return {
    general: {
      logging: { enabled: true, logLevel: "debug" },
      name,
      id: `${name}-${Date.now()}`,
      unit: "m3/h"
    },
    functionality: {
      softwareType: "pumpingStation",
      role: "stationcontroller"
    },
    basin: {
      volume: 43.75,
      height: 3.5,
      heightInlet: 0.3,
      heightOutlet: 0.2,
      heightOverflow: 3.0
    },
    hydraulics: {
      refHeight: "NAP",
      basinBottomRef: 0
    }
  };
}

function createLevelMeasurementConfig(name) {
  return {
    general: {
      logging: { enabled: true, logLevel: "debug" },
      name,
      id: `${name}-${Date.now()}`,
      unit: "m"
    },
    functionality: {
      softwareType: "measurement",
      role: "sensor",
      positionVsParent: "atEquipment"
    },
    asset: {
      category: "sensor",
      type: "level",
      model: "demo-level",
      supplier: "demoCo",
      unit: "m"
    },
    scaling: { enabled: false },
    smoothing: { smoothWindow: 5, smoothMethod: "none" }
  };
}

function createFlowMeasurementConfig(name, position) {
  return {
    general: {
      logging: { enabled: true, logLevel: "debug" },
      name,
      id: `${name}-${Date.now()}`,
      unit: "m3/s"
    },
    functionality: {
      softwareType: "measurement",
      role: "sensor",
      positionVsParent: position
    },
    asset: {
      category: "sensor",
      type: "flow",
      model: "demo-flow",
      supplier: "demoCo",
      unit: "m3/s"
    },
    scaling: { enabled: false },
    smoothing: { smoothWindow: 5, smoothMethod: "none" }
  };
}


function createMachineConfig(name) {

  curve = require('C:/Users/zn375/.node-red/public/fallbackData.json');
  return {
    
    general: {
        name: name,
        logging: {
            enabled: true,
            logLevel: "warn",
        }
    },
    asset: {
        supplier: "Hydrostal",
        type: "pump",
        category: "centrifugal",
        model: "hidrostal-H05K-S03R", // Ensure this field is present.
    }
  }
}

function createMachineStateConfig() {
  return {
    general: {
      logging: {
        enabled: true,
        logLevel: "debug",
      },
    },
    // Your custom config here (or leave empty for defaults)
    movement: {
      speed: 1,
    },
    time: {
      starting: 2,
      warmingup: 3,
      stopping: 2,
      coolingdown: 3,
    },
  }
}

// convenience for seeding measurements
function pushSample(measurement, type, value, unit) {
  const pos = measurement.config.functionality.positionVsParent;
  measurement.measurements
    .type(type)
    .variant("measured")
    .position(pos)
    .value(value, Date.now(), unit);
}

/** Demo *********************************************************************/
(async function demoStationWithPump() {
  const station = new PumpingStation(createPumpingStationConfig("PumpingStationDemo"));
  const pump = new RotatingMachine(createMachineConfig("Pump1"), createMachineStateConfig());

  const levelSensor = new Measurement(createLevelMeasurementConfig("WetWellLevel"));
  const upstreamFlow = new Measurement(createFlowMeasurementConfig("InfluentFlow", "upstream"));
  const downstreamFlow = new Measurement(createFlowMeasurementConfig("PumpDischargeFlow", "downstream"));


  // station uses the sensors
  /*
  station.childRegistrationUtils.registerChild(levelSensor, levelSensor.config.functionality.softwareType);
  station.childRegistrationUtils.registerChild(upstreamFlow, upstreamFlow.config.functionality.softwareType);
  station.childRegistrationUtils.registerChild(downstreamFlow, downstreamFlow.config.functionality.softwareType);
  */

  // pump owns the downstream flow sensor
  pump.childRegistrationUtils.registerChild(downstreamFlow, downstreamFlow.config.functionality.positionVsParent);
  station.childRegistrationUtils.registerChild(pump,"downstream");

  setInterval(() => station.tick(), 1000);

  // seed a starting level & flow
  /*
  pushSample(levelSensor, "level", 1.8, "m");
  pushSample(upstreamFlow, "flow", 0.35, "m3/s");
  pushSample(downstreamFlow, "flow", 0.20, "m3/s");
  */

  await new Promise(resolve => setTimeout(resolve, 20));

  // pump increases discharge flow
  /*
  pushSample(downstreamFlow, "flow", 0.28, "m3/s");
  pushSample(upstreamFlow, "flow", 0.40, "m3/s");
  pushSample(levelSensor, "level", 1.85, "m");
  */

await pump.handleInput("parent", "execSequence", "startup");
await pump.handleInput("parent", "execMovement", 50);
  console.log("Station state:", station.state);
  console.log("Station output:", station.getOutput());
  console.log("Pump state:", pump.state.getCurrentState());
})();


/*
//coolprop example
(async () => {
  const PropsSI = await coolprop.getPropsSI();

  // 👇 replace these with your real inputs
  const tC_input = 25;              // °C
  const pPa_input = 101325;         // Pa

  // Sanitize & convert
  const T = Number(tC_input) + 273.15;   // K
  const P = Number(pPa_input);           // Pa
  const fluid = 'Water';

  // Preconditions
  if (!Number.isFinite(T) || !Number.isFinite(P)) {
    throw new Error(`Bad inputs: T=${T} K, P=${P} Pa`);
  }
  if (T <= 0) throw new Error(`Temperature must be in Kelvin (>0). Got ${T}.`);
  if (P <= 0) throw new Error(`Pressure must be >0 Pa. Got ${P}.`);

  // Try T,P order
  let rho = PropsSI('D', 'T', T, 'P', P, fluid);
  // Fallback: P,T order (should be equivalent)
  if (!Number.isFinite(rho)) rho = PropsSI('D', 'P', P, 'T', T, fluid);

  console.log({ T, P, rho });

  if (!Number.isFinite(rho)) {
    console.error('Still Infinity. Extra checks:');
    console.error('typeof T:', typeof T, 'typeof P:', typeof P);
    console.error('Example known-good call:', PropsSI('D', 'T', 298.15, 'P', 101325, 'Water'));
  }
})();
*/