import java.util.Scanner;

/** ISPBilling makes bills based on ISPCharges
 *
 * @author Nancy Harris
 * @version V2 11/2013
 */
public class ISPBillingV2
{
   private static Scanner keyboard; 
	
   /** main creates the bill
    */
   public static void main(String[] args)
   {
      char pkg;
      double hours;
      double savings;
      ISPCharge charge;
      
      keyboard = new Scanner(System.in);
      printHeading();		
   	
      pkg = readPackage("Enter the package code (A, B, or C): ");
      hours = readHours("Enter the number of hours used: ");
   	
      charge = new ISPCharge (pkg, hours);
   	
      printBill(charge);
      
   }
	
   /** checkSavings will perform the output for calculating
     * the savings with other packages
     */
   public static void checkSavings(ISPCharge charge)
   {	
      double savings;
   	
      if (charge.saveWithB() || charge.saveWithC())
      {
         System.out.println();
      
         if (charge.saveWithB())
         {
            savings = charge.savingsWithB();
            System.out.printf("You could have saved $%,.2f with package B." + 
               	" Call 1-888-555-1234 for more information.\n", savings);
         }
         if (charge.saveWithC())
         {
            savings = charge.savingsWithC();
            System.out.printf("You could have saved $%,.2f with package C." + 
               	" Call 1-888-555-1234 for more information.\n", savings);
         }
      }
   }
	/** readPackage prompts the user and reads in the 
    *  package code. If a bad code is entered
    *  it returns a default.
    *
    *  @param prompt The prompt to use
    */
   public static char readPackage(String prompt)
   {
      String pkg;
   	
      System.out.print(prompt);
      pkg = keyboard.next();
            
      if(!(pkg.length() == 1 && pkg.toUpperCase().charAt(0) >= 'A' 
         && pkg.toUpperCase().charAt(0) <= 'C'))
      {
         System.out.printf("You entered %s. Using A\n", pkg);
         pkg = "A";
      }
   	
      return pkg.toUpperCase().charAt(0);
   }
	
   /** readHours reads in the hours defaulting if
    *  bad values are read in.
    *
    * @param prompt The prompt to use
    */
   public static double readHours(String prompt)
   {
      double hours;
   	
      System.out.print(prompt);
      if (keyboard.hasNextDouble())
      {
         hours = keyboard.nextDouble();
         if (hours < 0)
         {
            System.out.printf("You entered %f. Using 0\n", hours);
            hours = 0;
         }
      }
      else
      {
         System.out.printf("You entered %s. Using 0\n", keyboard.nextLine());
         hours = 0;
      }
      return hours;
   }
   
   /** printHours prints the additional hours
    *
    * @param charge The charge to print
    */
   public static void printAdditional(ISPCharge charge)
   {
      System.out.printf("Base Charge: $%.2f\n", charge.getBase());
      System.out.printf("Additional Hours: %.2f\n", charge.getAddtlHours());
   }
    
    /** printHeading prints the heading
    */
   public static void printHeading()
   {
      System.out.println("Dukes ISP Billing");
      System.out.println();
   }
    /** printBill prints this bill
     *
     * @param charge The ISPCharge for this bill
     */
   public static void printBill(ISPCharge charge)
   {
      System.out.println();
      System.out.println("Customer Bill");
      System.out.println();
      System.out.printf("Package: %s\n", charge.getPackage() );
      System.out.printf("Hours Used: %.2f\n\n", charge.getBaseHours() + charge.getAddtlHours());
      if(charge.needAddtlHours())
      {	
         printAdditional(charge);
      }
      System.out.println();
      System.out.printf("Total Charge: $%.2f\n", charge.calcCost());
      System.out.printf("Tax: $%.2f\n", charge.calcTax());
      System.out.println();
      System.out.printf("Pay this Amount: $%.2f\n", charge.calcCost() + charge.calcTax());
   	
      checkSavings(charge);
   }
}