package UPSTruckSimple;

/*
 * UPSTruck.java
 * Class supports working with a delivery truck
 * Some simplifying Assumptions:
 * 1) All boxes are the same size ==> 1 
 * 2) All locations exist
 * 3) A truck always arrives at its destination - no running out of gas ...
 * Created on April 15, 2003, 10:57 PM
 * Author: Dr Michael Redmond
 */

/**
 *
 * @author  mike
 */
public class UPSTruckSimple {
    
    
    ////////////////////////////////////////////////////////////////////////
    // Instance Variables
    ////////////////////////////////////////////////////////////////////////
    /**
     * unique (hopefully) identifier for the truck
     */
    private String truckID = "1";
    /** 
     * how many boxes the truck can hold at one time
     */
    private int capacity = 100;
    /**
     * how many boxes the truck curreently holds
     */
    private int contains = 0;
    /**
     * city that the truck is currently in
     */
    private String currLoc = "Philadelphia";
    /**
     * total number of boxes delivered by the truck since the start of the game/ simulation
     */
    private int boxesDelivered = 0;
    
    
    ////////////////////////////////////////////////////////////////////////
    // Constructors
    ////////////////////////////////////////////////////////////////////////
    /** 
     * Creates a new instance of UPSTruck 
     * Uses all default info
     */
    public UPSTruckSimple() {
    }
    
    /** 
     * Creates a new instance of UPSTruck 
     * Given truck id and location
     * rest takes defaults
     */
    public UPSTruckSimple(String id, String startLoc) {
        truckID = id;
        currLoc = startLoc;
    }
    
    /** 
     * Creates a new instance of UPSTruck 
     * Given truck id and location and capacity of truck
     * rest takes defaults
     */
    public UPSTruckSimple(String id, String startLoc, int holds) {
        truckID = id;
        currLoc = startLoc;
        capacity = holds;
    }
    
    
    ////////////////////////////////////////////////////////////////////////
    // Inspectors
    ////////////////////////////////////////////////////////////////////////
    
    /**
     * report the unique (we hope) identifier of the truck 
     */
    public String getTruckID() {
        return truckID;
    }
    
    /**
     * report the capacity of the truck - in number of boxes
     */
    public int getCapacity() {
        return capacity;
    }
    
    /**
     * report the contents of the truck - in number of boxes
     */
    public int getContains() {
        return contains;
    }
    
    /**
     * Report the current location of the truck
     */
    public String getCurrLoc() {
        return currLoc;
    }
    
    /**
     * Report the number of boxes delivered since the start of the game / simulation
     */
    public int getBoxesDelivered() {
        return boxesDelivered;
    }
    
    ////////////////////////////////////////////////////////////////////////
    // Pseudo Inspectors (find out about object - but not direct lookup of instance variable)
    ////////////////////////////////////////////////////////////////////////
    
    /** 
     * Report whether the truck is full
     * should never get over capacity, but this method will report full if somehow it does
     */
    public boolean isFull() {
        boolean full = false;
        if (contains >= capacity ) {
            full = true;
        }
        return full;
    }
    
    ////////////////////////////////////////////////////////////////////////
    // Mutators
    ////////////////////////////////////////////////////////////////////////
    
    /**
     * Change the truck id to a new value
     * no validation done - all ids accepted
     */
    public void setTruckID(String id) {
        truckID = id;
    }
    
    /**
     * Change the truck capacity - should only be done at the beginning
     * made private to control things
     * if negative capacity requested returns false
     */
    private boolean setCapacity(int maxItems) {
        if (maxItems <= 0) {
            return false;
        }
        else {
            capacity = maxItems;
            return true;
        }
    }
    
    /**
     * Change the truck contents - should only be done at the beginning
     * made private to control things
     * if negative contents specified returns false
     * if overcapacity, returns false
     */
    private boolean setContains(int number) {
        if (number < 0) {
            return false;
        }
        else if (number > capacity) {
            return false;
        }
        else {
            contains = number;
            return true;
        }
    }
    
    /**
     * Change the truck location to a new place
     * no validation done - all locations accepted
     */
    public void setCurrLoc(String newLoc) {
        currLoc = newLoc;
    }
    
    /**
     * Change the truck's number of boxes delivered - should only be done at the beginning
     * made private to control things - later changes should be done through dropoff
     * if negative contents specified returns false
     */
    private boolean setBoxesDelivered(int boxes) {
        if (boxes < 0) {
            return false;
        }
        else {
            boxesDelivered = boxes;
            return true;
        }
    }
    
    
    ////////////////////////////////////////////////////////////////////////
    // Methods with significant functionality
    ////////////////////////////////////////////////////////////////////////
    
    /** 
     * pickup a number of boxes in the current location
     * returns false if hit capacity
     */
    public boolean pickup(int numItems) {
        // try to update contents and see if it works
        if (!setContains(numItems + contains)) {
            // would be overcapacity
            // Policy - reject request - otherwise caller wouldn't know how many 
            //    were picked up
            return false;
        }
        else {
            // went ok
            return true;
        }
            
    }
    
    /** 
     * pickup a number of boxes in the given location
     * returns false if hit capacity or if can't make it to the location
     */
    public boolean pickup(int numItems, String where) {
        boolean madeIt = driveTo(where);
        if (!madeIt) {
            // ran out of gas or something
            return false;
        }
        else {
            // call other pickup to get it done since now in correct place
            boolean pickedOk = pickup(numItems);
            return pickedOk;
        }
    }
    
    /** 
     * drop off a number of boxes in the current location
     * returns false if hit empty before dropping all off
     */
    public boolean dropoff(int numItems) {
        // try to update contains and see if it works
        //    could fail if numItems is negative or would go below empty
        if (!setContains(contains - numItems)) {
            // would be under zero
            // Policy - reject request - otherwise caller wouldn't know how many 
            //    were dropped off
            return false;
        }
        else {
            // went ok
            // update number delivered - set will work since ensure adding 
            setBoxesDelivered(getBoxesDelivered() + numItems);
            return true;
        } 
    }
    
    /** 
     * drop off a number of boxes in the given location
     * returns false if try to drop off more than we have or if can't make it to the location
     */
    public boolean dropoff(int numItems, String where) {
        boolean madeIt = driveTo(where);
        if (!madeIt) {
            // ran out of gas or something
            return false;
        }
        else {
            // call other dropoff to get it done since now in correct place
            boolean droppedOk = dropoff(numItems);
            return droppedOk;
        }
    }
    
    /**
     * go to given location
     */
    public boolean driveTo(String where) {
        boolean ok = true; // hackup up in shortened version - always ok
        if (ok) {
            // made it there
            setCurrLoc(where);
        }
        return ok;
    }
    
    
    ////////////////////////////////////////////////////////////////////////
    // Methods overriding Object's versions
    ////////////////////////////////////////////////////////////////////////
    
    
    /**
     * produce a display friendly reprentation of a truck
     */
    public String toString() {
        String res = "Truck: " + getTruckID();
        res += " Loc: " + getCurrLoc();
        res += " Contains: " + getContains() + " of " + getCapacity() + " possible";
        res += " Boxes Delivered: " + getBoxesDelivered();
        return res;
    }
    
    
    
    ////////////////////////////////////////////////////////////////////////
    // Test Driver
    ////////////////////////////////////////////////////////////////////////
    /**
     * @param args the command line arguments
     * A simple test driver
     */
    public static void main(String[] args) {
        // default truck
        UPSTruckSimple truck1 = new UPSTruckSimple();
        System.out.println("Truck1: " + truck1);
        truck1.pickup(5);
        System.out.println("Truck1: " + truck1);
        truck1.pickup(5,"Boston");
        System.out.println("Truck1: " + truck1);
        if (!truck1.pickup(5,"Boston")){
            System.out.println("pickup failed");
        }
        System.out.println("Truck1: " + truck1);
        if (!truck1.dropoff(17,"Chicago")){
            System.out.println("dropoff failed");
        }
        System.out.println("Truck1: " + truck1);
        System.exit(0);
    }
    
}