Trip Clipper

// In-memory cache: avoids duplicate OSRM calls for the same coordinate pair
const _routeCache = new Map();

export async function fetchRouteTime(lat1, lng1, lat2, lng2, mode = 'driving') {
    const cacheKey = `${lat1},${lng1}-${lat2},${lng2}-${mode}`;
    if (_routeCache.has(cacheKey)) return _routeCache.get(cacheKey);

    // OSRM demo only exposes a driving profile — walking time is estimated
    const url = `https://router.project-osrm.org/route/v1/driving/
                 ${lng1},${lat1};${lng2},${lat2}?overview=false`;
    const data  = await fetch(url).then(r => r.json());
    const route = data.routes[0];

    const driveResult = {
        durationMin: Math.round(route.duration / 60),
        distanceMi:  +(route.distance / 1609.34).toFixed(1),
        mode: 'driving',
    };
    _routeCache.set(driveCacheKey, driveResult);

    if (mode === 'walking') {
        // ~3 mph ≈ 20 min/mile — derived from the routed driving distance
        return { ...driveResult, durationMin: Math.round(driveResult.distanceMi * 20), mode: 'walking' };
    }

    return driveResult;
}

// Budget and proximity are computable from data — uniqueness and group appeal are not
const calculateAutoScores = (item) => {
    const price = parseFloat(item.price) || 0;
    const budgetScore =
        price === 0   ? 10 :
        price <= 20   ?  8 :
        price <= 50   ?  6 :
        price <= 100  ?  4 : 2;

    const dist = getDistance(hotel.lat, hotel.lng, item.lat, item.lng);
    const timeScore =
        dist <= 1.0  ? 10 :
        dist <= 3.0  ?  8 :
        dist <= 10.0 ?  6 :
        dist <= 30.0 ?  4 : 2;

    return { budgetScore, timeScore };
};

// Objective fields are auto-scored; subjective fields come from human ratings
const buildOption = (item) => ({
    scores: {
        budget:     budgetScore,              // computed from price
        time:       timeScore,                // computed from distance to hotel
        uniqueness: item.rating_uniqueness || 5,  // human-rated on Idea Board
        group:      item.rating_group      || 5,  // human-rated on Idea Board
    }
});

// Energy level set once at trip creation — configures every behavioral limit downstream
const THRESHOLDS = {
    chill:    { daily: 15, gap: 8,  maxActivities: 2, maxTransits: 1, dailyTimeMin:  30, gapTimeMin: 15 },
    balanced: { daily: 30, gap: 15, maxActivities: 4, maxTransits: 3, dailyTimeMin:  60, gapTimeMin: 30 },
    packed:   { daily: 60, gap: 25, maxActivities: 7, maxTransits: 5, dailyTimeMin: 120, gapTimeMin: 45 },
};

const ENERGY_CAPS = { chill: 2, balanced: 4, packed: 7 };

// DailySchedule — amber warnings fire when daily travel or gap thresholds are exceeded
const limits = THRESHOLDS[tripEnergy] || THRESHOLDS.balanced;

// CityItinerary — Good Enough Mode disables selection once the day is at capacity
const maxPerDay = ENERGY_CAPS[tripEnergy] || 4;