PricingService.java

package com.parking.service;

import com.parking.model.ParkingSpot;

/**
 * Smart pricing engine with dynamic rates based on spot type and duration.
 */
public class PricingService {

    // Base rates per hour (in INR)
    private static final double REGULAR_RATE      = 30.0;
    private static final double COMPACT_RATE      = 25.0;
    private static final double PREMIUM_RATE      = 60.0;
    private static final double EV_RATE           = 40.0;
    private static final double HANDICAPPED_RATE  = 15.0;

    // Free grace period (15 minutes)
    private static final long GRACE_PERIOD_MINUTES = 15;

    // Peak hour surcharge (8AM–10AM, 5PM–8PM) — 50% extra
    private static final double PEAK_SURCHARGE = 1.5;

    public double calculateCharge(ParkingSpot.SpotType spotType, long durationMinutes) {
        if (durationMinutes <= GRACE_PERIOD_MINUTES) {
            return 0.0; // Free within grace period
        }

        double baseRate = getBaseRate(spotType);
        double hours = Math.ceil((durationMinutes - GRACE_PERIOD_MINUTES) / 60.0);
        if (hours < 1) hours = 1;

        double charge = baseRate * hours;

        // Apply peak hour surcharge
        int currentHour = java.time.LocalTime.now().getHour();
        boolean isPeakHour = (currentHour >= 8 && currentHour <= 10) || (currentHour >= 17 && currentHour <= 20);
        if (isPeakHour) {
            charge *= PEAK_SURCHARGE;
        }

        // Daily cap: max 12 hours billing
        double maxDailyCharge = baseRate * 12;
        return Math.min(charge, maxDailyCharge);
    }

    private double getBaseRate(ParkingSpot.SpotType type) {
        switch (type) {
            case COMPACT:     return COMPACT_RATE;
            case PREMIUM:     return PREMIUM_RATE;
            case EV_CHARGING: return EV_RATE;
            case HANDICAPPED: return HANDICAPPED_RATE;
            default:          return REGULAR_RATE;
        }
    }

    public double getHourlyRate(ParkingSpot.SpotType type) {
        return getBaseRate(type);
    }

    public boolean isGracePeriod(long durationMinutes) {
        return durationMinutes <= GRACE_PERIOD_MINUTES;
    }
}