const { POSITIONS } = require('generalFunctions');
const { groupFlow, groupPower, groupNCog } = require('../groupOps/groupCurves');

// Aggregations across every machine in the group.
//
// calcAbsoluteTotals scans the full input-curve envelope (worst/best case
// over the pump's entire pressure range). calcDynamicTotals reads the
// current group operating point (after equalize). activeTotals only sums
// machines that are operationally active right now.
class TotalsCalculator {
    constructor(ctx = {}) {
        // ctx: { machines, unitPolicy, logger, operatingPoint, isMachineActive }
        // operatingPoint is a GroupOperatingPoint instance (for readChild).
        // isMachineActive is delegated back to the orchestrator so the
        // state-machine vocabulary lives in one place.
        this.ctx = ctx;
        this.dynamicTotals  = { flow: { min: Infinity, max: 0 }, power: { min: Infinity, max: 0 }, NCog: 0 };
        this.absoluteTotals = { flow: { min: Infinity, max: 0 }, power: { min: Infinity, max: 0 } };
    }

    get machines()         { return this.ctx.machines || {}; }
    get unitPolicy()       { return this.ctx.unitPolicy; }
    get logger()           { return this.ctx.logger; }
    get operatingPoint()   { return this.ctx.operatingPoint; }

    isMachineActive(id) {
        if (typeof this.ctx.isMachineActive === 'function') return this.ctx.isMachineActive(id);
        const s = this.machines[id]?.state?.getCurrentState?.();
        return s === 'operational' || s === 'accelerating' || s === 'decelerating';
    }

    calcAbsoluteTotals() {
        const out = { flow: { min: Infinity, max: 0 }, power: { min: Infinity, max: 0 } };

        Object.values(this.machines).forEach(machine => {
            const totals = { flow: { min: Infinity, max: 0 }, power: { min: Infinity, max: 0 } };
            Object.entries(machine.predictFlow.inputCurve).forEach(([pressure, xyCurve]) => {
                const minFlow  = Math.min(...xyCurve.y);
                const maxFlow  = Math.max(...xyCurve.y);
                const minPower = Math.min(...machine.predictPower.inputCurve[pressure].y);
                const maxPower = Math.max(...machine.predictPower.inputCurve[pressure].y);
                if (minFlow  < totals.flow.min)  totals.flow.min  = minFlow;
                if (minPower < totals.power.min) totals.power.min = minPower;
                if (maxFlow  > totals.flow.max)  totals.flow.max  = maxFlow;
                if (maxPower > totals.power.max) totals.power.max = maxPower;
            });
            if (totals.flow.min  < out.flow.min)  out.flow.min  = totals.flow.min;
            if (totals.power.min < out.power.min) out.power.min = totals.power.min;
            out.flow.max  += totals.flow.max;
            out.power.max += totals.power.max;
        });

        // Empty-group + sentinel reset: Infinity / -Infinity are math
        // artefacts of the reducer's initial values; downstream code
        // expects clean zeros.
        if (out.flow.min  === Infinity)  { this.logger?.warn?.('Flow min Infinity — zeroing.');  out.flow.min  = 0; }
        if (out.power.min === Infinity)  { this.logger?.warn?.('Power min Infinity — zeroing.'); out.power.min = 0; }
        if (out.flow.max  === -Infinity) { this.logger?.warn?.('Flow max -Infinity — zeroing.');  out.flow.max  = 0; }
        if (out.power.max === -Infinity) { this.logger?.warn?.('Power max -Infinity — zeroing.'); out.power.max = 0; }

        this.absoluteTotals = out;
        return out;
    }

    calcDynamicTotals() {
        const out = { flow: { min: Infinity, max: 0, act: 0 }, power: { min: Infinity, max: 0, act: 0 }, NCog: 0 };
        const fUnit = this.unitPolicy.canonical.flow;
        const pUnit = this.unitPolicy.canonical.power;

        Object.values(this.machines).forEach(machine => {
            if (!machine.hasCurve) {
                this.logger?.error?.(`Machine ${machine.config?.general?.id} has no valid curve — skipping.`);
                return;
            }
            const gpf = groupFlow(machine);
            const gpp = groupPower(machine);

            const minFlow  = gpf.currentFxyYMin;
            const maxFlow  = gpf.currentFxyYMax;
            const minPower = gpp.currentFxyYMin;
            const maxPower = gpp.currentFxyYMax;

            const actFlow  = this.operatingPoint?.readChild(machine, 'flow',  'predicted', POSITIONS.DOWNSTREAM,   fUnit) || 0;
            const actPower = this.operatingPoint?.readChild(machine, 'power', 'predicted', POSITIONS.AT_EQUIPMENT, pUnit) || 0;

            if (minFlow  < out.flow.min)  out.flow.min  = minFlow;
            if (minPower < out.power.min) out.power.min = minPower;
            out.flow.max   += maxFlow;
            out.power.max  += maxPower;
            out.flow.act   += actFlow;
            out.power.act  += actPower;
            out.NCog       += groupNCog(machine);
        });

        this.dynamicTotals = out;
        return out;
    }

    activeTotals() {
        const out = { flow: { min: 0, max: 0 }, power: { min: 0, max: 0 }, countActiveMachines: 0 };

        Object.entries(this.machines).forEach(([id, machine]) => {
            if (!this.isMachineActive(id)) return;
            const gpf = groupFlow(machine);
            const gpp = groupPower(machine);
            out.flow.min  += gpf.currentFxyYMin;
            out.flow.max  += gpf.currentFxyYMax;
            out.power.min += gpp.currentFxyYMin;
            out.power.max += gpp.currentFxyYMax;
            out.countActiveMachines += 1;
        });

        return out;
    }
}

module.exports = TotalsCalculator;