#include <string.h>
#include "structures.h"
#include "AOPcalendar.h"
#include "t_list.c"
   
char *copy_string(char *st);
struct term *t_null();
struct term *t_cons(struct term *t, struct term *list);
struct term *t_object(struct term *l);
struct term *t_next(struct term *l);
int t_length(struct term *list);

term_ptr term_template(char *c);
term_ptr read_pipe(int pipe_id);
void write_pipe(int pipe_id,term_ptr term);
void userInsertAppointment(int year, int month, int day, dayAppP day_rec);
void userDeleteAppointment(int year, int month, int day, dayAppP day_rec);

void send_to_agent(term_ptr agent_term, term_ptr term);
dayAppP apiGetDateAppointments(int year, int month, int day, int *counter);
dayAppP apiGetAppointment(int year, int month, int day, int start);

extern term_ptr default_scheduler;

/*
============================================================
|                      convert_date()                      |
|----------------------------------------------------------|
| Params : 1) a  dayApp structure                          |

| Desc   : converts the structure to the corresponding term|
|                                                          |
| Returns: the term                                        |
|==========================================================|
*/
term_ptr convert_date(dayAppP day)
{
   int i;
   term_ptr temp;
   term_ptr message;
   if(day==NULL)
   {
      message=term_template("i");
      message->functor=0;
   }
   else
   {
      message=term_template("iissnn6");
      message->term_type=TUPLE;
      message->argument_array[0]->functor=day->start;
      message->argument_array[1]->functor=day->end;
      message->argument_array[2]->const_string=copy_string(day->title);
      message->argument_array[3]->const_string=copy_string(day->info);
      switch( day->status)
      {
      case MEETING:
      case BLOCKED:
      case PRIVATE:
         message->argument_array[4]->functor=day->status;
         break;
      default:
         message->argument_array[4]->functor=NEW;
         break;
      }
      free(message->argument_array[5]);
      message->argument_array[5]=t_null();
      for(i=day->participants_count-1;i>=0;i--)
      {
         temp=term_template("s");
         temp->const_string=copy_string(day->participants[i].alias);
         message->argument_array[5]=t_cons(temp,message->argument_array[5]);
      }
   }
   return message;  
}

void userInsertAppointment(int year,
                           int month,
                           int day,
                           dayAppP day_rec)
{
   term_ptr message=term_template("iiin4");
   message->functor=INSERT;
   message->argument_array[0]->functor=year;
   message->argument_array[1]->functor=month;
   message->argument_array[2]->functor=day;
   free(message->argument_array[3]);
   message->argument_array[3]=convert_date(day_rec);
   send_to_agent(default_scheduler,message);
   free_term(message);
}

void userScheduleAppointment(int year,
                             int month,
                             int day,
                             dayAppP day_rec)
{
   term_ptr message=term_template("iiin4");
   message->functor=SCHEDULE;
   message->argument_array[0]->functor=year;
   message->argument_array[1]->functor=month;
   message->argument_array[2]->functor=day;
   free(message->argument_array[3]);
   message->argument_array[3]=convert_date(day_rec);
   send_to_agent(default_scheduler,message);
   free_term(message);
}

void userDeleteAppointment(int year,
                           int month,
                           int day,
                           dayAppP day_rec)
{
   term_ptr message=term_template("iiin4");
   message->functor=DELETE;
   message->argument_array[0]->functor=year;
   message->argument_array[1]->functor=month;
   message->argument_array[2]->functor=day;
   free(message->argument_array[3]);
   message->argument_array[3]=convert_date(day_rec);
   send_to_agent(default_scheduler,message);
   free_term(message);
}


/*
============================================================
|                     unconvert_date()                     |
|----------------------------------------------------------|
| Params : 1)  a term representing a date structure        |

| Desc   : converts the term representation to struct representation
|                                                          |
| Returns: a struct                                        |
|==========================================================|
*/
dayAppP unconvert_date(term_ptr term)
{
   int i;
   term_ptr temp;
   char *name;
   dayAppP day=(dayAppP)malloc(sizeof(struct dayApp));
   term_ptr *arg=term->argument_array;
   day->start=arg[0]->functor;
   day->end=arg[1]->functor;
   strcpy(day->title,arg[2]->const_string);
   strcpy(day->info,arg[3]->const_string);
   day->status=arg[4]->functor;
   day->participants_count=t_length(arg[5]);
   if (day->participants_count>MAX_PARTICIPANTS)
   {
      printf("error: too many participants in meeting\n");
      return NULL;
   }
   else
   {
      temp=arg[5];
      for (i=0;i<day->participants_count;i++)
      {
         name=t_object(temp)->const_string;
         if (strlen(name)>=40)
         {
            printf("Error: name too long\n");
            return NULL;
         }
         else
         {
            strcpy(day->participants[i].alias,name);
            temp=t_next(temp);
         }
      }
   }
   return day;
}


/*
============================================================
|                   insert_appointment()                   |
|----------------------------------------------------------|
| Params : 1)a term representing an insert update          |
| Desc   : converts the term to the right data structure,
           and calls the relevant api function
|==========================================================|
*/
void insert_appointment(term_ptr term)
{
   term_ptr agent=term->argument_array[0];
   term_ptr *arg=term->argument_array[1]->argument_array;
   dayAppP day_rec;
   term_ptr reference=arg[0];
   int year=arg[1]->functor;
   int month=arg[2]->functor;
   int day=arg[3]->functor;
   day_rec=unconvert_date(arg[4]);
   apiInsertAppointment(year,month,day,day_rec);
   send_to_agent(agent,reference);
   free_term(term);
   free(day_rec);
}
/*
============================================================
|                   delete_appointment()                   |
|----------------------------------------------------------|
| Params : 1)a term representing a delete  update          |
| Desc   : converts the term to the right data structure,
           and calls the relevant api function
|==========================================================|
*/
void delete_appointment(term_ptr term)
{
   term_ptr agent=term->argument_array[0];
   term_ptr *arg=term->argument_array[1]->argument_array;
   dayAppP day_rec;
   term_ptr reference=arg[0];
   int year=arg[1]->functor;
   int month=arg[2]->functor;
   int day=arg[3]->functor;
   day_rec=unconvert_date(arg[4]);
   apiDeleteAppointment(year,month,day,day_rec);
   send_to_agent(agent,reference);
   free_term(term);
   free(day_rec);
}

/*
============================================================
|                   enquire_appointment()                  |
|----------------------------------------------------------|
| Params : 1)a term representing an enquiry to the database|
| Desc   : replies to the enquiry                          |
|                                                          |
|==========================================================|
*/
void enquire_appointment(term_ptr term)
{
   term_ptr message;
   term_ptr enquire_list(term_ptr,int,int,int);
   term_ptr enquire_start(term_ptr,int,int,int,int);
   term_ptr scheduler=term->argument_array[0];
   term_ptr *arg=term->argument_array[1]->argument_array;
   term_ptr ref=arg[0];
   int enquiry=arg[1]->functor;
   int year=arg[2]->functor;
   int month=arg[3]->functor;
   int day=arg[4]->functor;
   switch(enquiry)
   {
   case LIST:
      message=enquire_list(ref,year,month,day);
      break;
   case START:
   {
      int hour=arg[5]->functor;
      message=enquire_start(ref,year,month,day,hour);
   }
      break;
   }
   send_to_agent(scheduler,message);
   free_term(term);
   free_term(message);
}

term_ptr enquire_list(term_ptr ref,int year,int month,int day)
{
   term_ptr e_list=t_null();
   term_ptr message=term_template("nn2");
   int i,counter;
   dayAppP answer=apiGetDateAppointments(year,month,day,&counter);
   for(i=0;i<counter;i++)
   {
      e_list=t_cons(convert_date(&answer[i]),e_list);
   }
   free(answer);
   free(message->argument_array[0]);
   free(message->argument_array[1]);
   message->term_type=TUPLE;
   message->argument_array[0]=ref;
   message->argument_array[1]=e_list;
   return message;
}

term_ptr enquire_start(term_ptr ref,int year,int month,int day,int hour)
{
   term_ptr appointment;
   term_ptr message=term_template("nn2");
   int i,counter;
   dayAppP answer=apiGetAppointment(year,month,day,hour);
   appointment=convert_date(answer);
   free(answer);
   free(message->argument_array[0]);
   free(message->argument_array[1]);
   message->term_type=TUPLE;
   message->argument_array[0]=ref;
   message->argument_array[1]=appointment;
   return message;
}