Time_scheduling.cpp

#include "metro.hpp"

// Returns true if, at the given local time, the metro is running.
// HMRL's published operating window is roughly 6:00 AM to 11:00 PM daily.
bool isMetroOpenNow(tm* ltm) {
    int hour = ltm->tm_hour;
    return (hour >= OPERATING_OPEN_HOUR && hour < OPERATING_CLOSE_HOUR);
}

// Builds a friendly "metro is closed, first train at X" message.
string nextTrainMessage(tm* ltm) {
    tm next = *ltm;
    if (ltm->tm_hour < OPERATING_OPEN_HOUR) {
        // Same day, just hasn't opened yet.
        next.tm_hour = OPERATING_OPEN_HOUR;
        next.tm_min = 0;
        next.tm_sec = 0;
    } else {
        // Past closing time tonight; first train is 6:00 AM tomorrow.
        next.tm_mday += 1;
        next.tm_hour = OPERATING_OPEN_HOUR;
        next.tm_min = 0;
        next.tm_sec = 0;
    }
    time_t t = mktime(&next);
    tm* fixed = localtime(&t);
    char buffer[80];
    strftime(buffer, sizeof(buffer), "%I:%M %p", fixed);
    return string(buffer);
}

// Peak windows: 7-10 AM and 5-8 PM, matching typical HMRL peak commute hours.
bool isPeakHour(tm* ltm) {
    int hour = ltm->tm_hour;
    bool morning = (hour >= PEAK_MORNING_START && hour < PEAK_MORNING_END);
    bool evening = (hour >= PEAK_EVENING_START && hour < PEAK_EVENING_END);
    return morning || evening;
}

int getHeadwayMins(tm* ltm) {
    return isPeakHour(ltm) ? PEAK_HEADWAY_MINS : OFFPEAK_HEADWAY_MINS;
}

// Flat platform-walk penalty applied once per line change in the path.
// Real interchanges (Ameerpet, MGBS, Parade Ground/JBS) all require a walk
// between platforms; we don't currently model differing walk distances per
// interchange, so this uses one flat value for all of them.
int getTransferDelayMins(vector<int>& path) {
    int transfers = countTransfers(path);
    return transfers * TRANSFER_WALK_MINS;
}

// Admin-triggered "Technical Snag" delay: if any segment of the path lies on
// a line currently flagged with a snag, add a flat delay. Applied once per
// distinct affected line touched by the path (so a journey crossing two
// snagged lines is delayed twice, not once).
int getLineSnagDelayMins(vector<int>& path) {
    bool touched[3] = {false, false, false};
    for (size_t i = 0; i < path.size(); i++) {
        int li = getLineIndex(path[i]);
        if (li >= 0) touched[li] = true;
    }
    int delay = 0;
    for (int i = 0; i < 3; i++) {
        if (touched[i] && line_snag[i]) delay += LINE_SNAG_DELAY_MINS;
    }
    return delay;
}