//  Calendars.m  Copyright (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2013-07-12  Objective-C version of this file was created.
//  2013-07-12  Last modification.

//  This programs demonstrates
//    - the use of the ISODate class to print calendars
//    - deriving a subclass from a class

//  No NSString strings are in use in this program.
//  The program was made with C-style strings because
//  they can be printed easily with the printf() function.

#include  <stdio.h>
#import   <Foundation/Foundation.h>
#import   "class_isodate_oc.h"

@interface  EnglishCalendar : NSObject
{
   int  this_month ;
   int  this_year ;

   char**  names_of_months ;   // C-style array of strings
   char*   week_description ;  // C-style string
}

- (id) init_year:   (int) given_year
       and_month:   (int) given_month ;
       
- (void) print ;

@end

@implementation EnglishCalendar
       
- (id) init_year:   (int) given_year
       and_month:   (int) given_month
{
   self = [ super init ] ;
   
   if ( self )
   {
      static char*  english_names_of_months[]  =  

         { "January", "February", "March", "April",
           "May", "June", "July", "August",
           "September", "October", "November", "December" } ;

      static char   english_week_description[]  =

          " Week   Mon  Tue  Wed  Thu  Fri  Sat  Sun" ;

      this_month  =  given_month ;
      this_year   =  given_year  ;

      names_of_months   =  english_names_of_months ;

      week_description  =  english_week_description ;
   }
   
   return self ;
}


- (void) print
{
   ISODate* a_day_in_this_month = [ [ ISODate alloc ] init_year: this_year
                                                     and_month: this_month
                                                     and_day: 1 ] ;
   int day_of_week_index   =  0 ;

   int day_of_week_of_first_day  =
              [ a_day_in_this_month  index_for_day_of_week ] ;

   printf( "\n\n   %s   %d\n\n%s\n\n", names_of_months[ this_month - 1 ],
           this_year,   week_description ) ;
   printf( "%4d  ", [ a_day_in_this_month  get_week_number ] ) ;

   // The first week of a month is often an incomplete week, 
   // i.e., the first part of week belongs to the previous
   // month. In place of the days that belong to the previous
   // month we print just spaces.

   while ( day_of_week_index != day_of_week_of_first_day )
   {
      printf(  "     " ) ;
      day_of_week_index  ++ ;
   }

   while ( this_month  ==  [ a_day_in_this_month  month ] )
   {
      if ( day_of_week_index  >=  7 )
      {
         printf( "\n%4d  ", [ a_day_in_this_month  get_week_number ] ) ;

         day_of_week_index  =  0 ;
      }

      printf( "%5d", [ a_day_in_this_month day ] ) ;

      [ a_day_in_this_month increment ] ;
      day_of_week_index  ++  ;
   }

   printf( "\n" ) ;
}

@end // end of EnglishCalendar implementation

// Next, we'll specify a class named SpanishCalendar
// that inherits the class above. The new class differs from
// its superclass only so that it has a new kind of constructor.

@interface SpanishCalendar : EnglishCalendar

- (id) init_year:   (int) given_year
       and_month:   (int) given_month ;

@end


@implementation SpanishCalendar

- (id) init_year:   (int) given_year
       and_month:   (int) given_month
{
   self = [ super init_year: given_year
                  and_month: given_month ] ;
   
   if ( self )
   {
      static char*  spanish_names_of_months[]  =

      { "Enero", "Febrero", "Marzo", "Abril",
        "Mayo", "Junio", "Julio", "Agosto",
        "Septiembre", "Octubre", "Noviembre", "Deciembre" } ;

      static char   spanish_week_description[]  =

        "Semana  Lun  Mar  Mie  Jue  Vie  Sab  Dom" ;

      names_of_months   =  spanish_names_of_months ;
      week_description  =  spanish_week_description ;
   }
   
   return self ;
}

@end


int main( void )
{
   NSAutoreleasePool* autorelease_pool = [ [ NSAutoreleasePool alloc ] init ] ;
   
   EnglishCalendar*  an_english_calendar =
         [ [ EnglishCalendar alloc ] init_year: 2013
                                     and_month: 10 ] ;

   [ an_english_calendar  print ] ;

   SpanishCalendar*  a_spanish_calendar =
         [ [ SpanishCalendar alloc ] init_year: 2014
                                     and_month: 12 ] ;

   [ a_spanish_calendar  print ] ;

   [ autorelease_pool drain ] ;
}