package edu.stevens.smartpark;

/** Dependency-free tests that fail the process when parking rules break. */
public final class ParkingLotTest {
    private ParkingLotTest() {
    }

    public static void main(String[] args) {
        testArrivalsAndDepartures();
        testFullAndEmptyBoundaries();
        testInvalidStartingValues();
        System.out.println("ParkingLot tests passed");
    }

    private static void testArrivalsAndDepartures() {
        ParkingLot lot = new ParkingLot("Babbio Garage", 120, 42);
        check(lot.getName().equals("Babbio Garage"), "name");
        check(lot.getCapacity() == 120, "capacity");
        check(lot.getOccupiedSpaces() == 78, "initial occupied spaces");
        lot.vehicleEnters();
        check(lot.getAvailableSpaces() == 41, "arrival decreases availability");
        lot.vehicleLeaves();
        check(lot.getAvailableSpaces() == 42, "departure restores availability");
    }

    private static void testFullAndEmptyBoundaries() {
        ParkingLot full = new ParkingLot("River Lot", 1, 0);
        check(full.isFull(), "zero available spaces means full");
        expectIllegalState(full::vehicleEnters);
        full.vehicleLeaves();
        check(full.getAvailableSpaces() == 1, "departure from full lot");
        expectIllegalState(full::vehicleLeaves);
        full.vehicleEnters();
        check(full.isFull(), "arrival fills the last space");
    }

    private static void testInvalidStartingValues() {
        expectIllegalArgument(() -> new ParkingLot("", 10, 5));
        expectIllegalArgument(() -> new ParkingLot("Lot", -1, 0));
        expectIllegalArgument(() -> new ParkingLot("Lot", 10, -1));
        expectIllegalArgument(() -> new ParkingLot("Lot", 10, 11));
    }

    private static void check(boolean condition, String description) {
        if (!condition) {
            throw new AssertionError("Failed: " + description);
        }
    }

    private static void expectIllegalState(Runnable action) {
        try {
            action.run();
        } catch (IllegalStateException expected) {
            return;
        }
        throw new AssertionError("Expected IllegalStateException");
    }

    private static void expectIllegalArgument(Runnable action) {
        try {
            action.run();
        } catch (IllegalArgumentException expected) {
            return;
        }
        throw new AssertionError("Expected IllegalArgumentException");
    }
}