1 files changed, 51 insertions, 51 deletions

diff --git a/Week14 Route 66/src/OO14route66/Model.java b/Week14 Route 66/src/OO14route66/Model.java
index f4e725f..ee9da42 100644
--- a/Week14 Route 66/src/OO14route66/Model.java
+++ b/Week14 Route 66/src/OO14route66/Model.java
@@ -1,10 +1,7 @@
 package OO14route66;
 
-import com.camilstaps.route66.Crossing;
 import java.util.ArrayList;
 import java.util.Observable;
-import java.util.logging.Level;
-import java.util.logging.Logger;
 import javax.swing.JFrame;
 
 /**
@@ -21,7 +18,12 @@ public class Model extends Observable
         NUMBEROFCARS = 5 * DIRECTIONS;   // total number of cars in system
         
     private final ArrayList<JFrame> views;
-    private final Crossing crossing = new Crossing(this, Direction.North);
+    //private final Crossing crossing = new Crossing(this, Direction.North);
+    
+    private Direction allowed;
+    private boolean crossingWaiting = false;
+    private long lastCrossingChange = 0;
+    private static final int MIN_CROSS_TIME = 1000;
 
     /**
      * Constructor: create all cars
@@ -75,62 +77,60 @@ public class Model extends Observable
     public synchronized boolean isSafeLocation(Car car, int requested_location) {
         Car that_car = cars[car.getNumber() < DIRECTIONS ? car.getNumber() + NUMBEROFCARS - DIRECTIONS : car.getNumber() - DIRECTIONS];
         
-        boolean ok;
-        
-        System.err.println("Car " + car.getNumber() + " requests safety.");
-        
-        do {
-            ok = !(that_car.getLocation() > requested_location &&
-                    that_car.getLocation() < requested_location + Car.CARLENGTH + Car.MINCARSPACE);
+        boolean ok = !(that_car.getLocation() > requested_location &&
+                that_car.getLocation() < requested_location + Car.CARLENGTH + Car.MINCARSPACE);
 
-//            if (!ok && that_car.getDriver().getWaitingToCross()) {
-//                crossing.doRequest();
-//            }
-            
-            if (car.isInFrontOfCrossing() && !crossing.isAllowed(car.getDirection())) {
-                System.err.println("Requesting switch for car " + car.getNumber());
-                ok = false;
-                //if (!car.getDriver().getWaitingToCross()) {
-                    //car.getDriver().setWaitingToCross(true);
-                    ok = crossing.doRequest();
-                    //car.getDriver().setWaitingToCross(!ok);
-                //}
-            }
-            
-            if (!ok) {
-                System.err.println("Car " + car.getNumber() + " waiting.");
-                try {
-                    wait();
-                } catch (InterruptedException ex) {
-                }
-                System.err.println("Car " + car.getNumber() + " acquired lock.");
+        if (car.isInFrontOfCrossing() && !isCrossingAllowed(car.getDirection())) {
+            ok = doCrossingRequest();
+        }
+
+        if (!ok) {
+            try {
+                wait();
+            } catch (InterruptedException ex) {
             }
-        } while (!ok);
-        
-        System.err.println("Car " + car.getNumber() + " has safe location.");
+        }
         
         return ok;
     }
     
-    public synchronized boolean isNoCarsOnCrossing() {
-        boolean ok = false;
-        while (!ok) {
-            ok = true;
-            for (Car car : cars) {
-                if (car.isOnCrossing()) {
-                    System.err.println("Car " + car.getNumber() + " is on crossing.");
-                    ok = false;
-                }
+    public synchronized boolean isCarsOnCrossing() {
+        for (Car car : cars) {
+            if (car.isOnCrossing()) {
+                return true;
             }
-            if (!ok) {
-                System.err.println("Checking crossing waiting");
-                try {
-                    wait();
-                } catch (InterruptedException ex) {
-                }
-                System.err.println("Checking crossing");
+        }
+        return false;
+    }
+    
+    public synchronized void doSwitchCrossing() {
+        crossingWaiting = true;
+        while (isCarsOnCrossing()) {
+            try {
+                wait();
+            } catch (InterruptedException ex) {
             }
         }
+        System.err.println("Switching");
+        if (allowed == Direction.East || allowed == Direction.West) {
+            allowed = Direction.North;
+        } else {
+            allowed = Direction.East;
+        }
+        System.err.println("Switched to " + allowed);
+        crossingWaiting = false;
+        lastCrossingChange = System.currentTimeMillis();
+    }
+    
+    public synchronized boolean isCrossingAllowed(Direction direction) {
+        return !crossingWaiting && (direction == allowed || Direction.opposite(direction) == allowed);
+    }
+    
+    public synchronized boolean doCrossingRequest() {
+        if (crossingWaiting || System.currentTimeMillis() - lastCrossingChange < MIN_CROSS_TIME) {
+            return false;
+        }
+        doSwitchCrossing();
         return true;
     }
 }