Maximuscode

#include <stdio.h>  //Standard Input Output Header
#include <windows.h>
#include <stdlib.h>   //Standard Library Header
#include <string.h>  //String Header
#include <conio.h>
#include <ctype.h>  //Include header to handle character for validation purpose
#include <time.h>   //Time header for server time option.
/* ASCII Code Declaration */
#define ENTER 13
#define BKSP 8
#define ESC 27

/* System Function */
void testing();
void gotoxy(int x, int y);
int  escexit(char pkey);
int  goback_previousmenu(char pkey);
void cls();
void invalid_msg();
void error_msg();

/* Validation Function */
int  selection_limiter(int type, int upper_limit, int lower_limit);
char *data_entry(int type, int size_limit);
int  alpha_str_validation(char input[]);
int  num_str_validation(char input[]);

/* Login Function */
void usertype_file_verification();
void usertype_username_retrieval();
void usertype_password_retrieval();
int  login_validation();

/* Data Entry for Patient */
int  pat_numofline_get();
int  pat_id_get();
void pat_firstname_get();
void pat_lastname_get();
void pat_name_merge();
void pat_gender_get();
void pat_age_get();
void pat_ic_get();
void pat_contact_get();
int  patient_add();

/* Data Entry for Appointment */
int app_numofline_get();
int app_id_get();
void app_type_get();
void app_doctor_get();
void app_time_get();
void date_merger(int date[], int month[], int year[]);
int  appointment_add();

/* Data Modification & Display for Patient */
char *name_splitter(char input[]);
void patient_info_retrieval(int type);
void patient_info_print();
int  patient_view();
int  pat_line_locator(char input[]);
int  patient_modify();
int  patient_delete();

/* Data Modification & Display for Appointment*/
void appointment_info_retrieval(int type);
void appointment_info_print();
int  appointment_view();

/* Search Function */
char *search_name();
char *search_id();
int patient_search();
int appointment_search();
int appointment_delete();
/* Navigation Menu */
void usertype_nav();
int  actiontype_nav();
int  pat_rec_action_nav();
int app_rec_action_nav();
int  pat_doc_action_nav();
int app_doc_action_nav();

/* Selection Menu */
void usertype_selection();
void actiontype_selection();
int  pat_rec_action_selection();
int  app_rec_action_selection();
int  pat_doc_action_selection();
int  app_doc_action_selection();
void pat_search_selection();

/* Global Variable for Choice */
char usertype, actiontype, action, search_choice;

FILE *fp, *fp2;

COORD coord={0,0};

/* Structure for Login User */
struct user{
    char username[30];
    char password[30];
}user;

/* Structure for Patient */
struct patient{
    char id[10];
    char first_name[25];
    char last_name[25];
    char full_name[50];
    char gender;
    unsigned int age;
    char contact_no[11];
    char ic[12];
}pat;

/* Structure for Appointment */
struct appointment{
    char pat_id[10];
    char app_id[10];
    char name[50];
    char gender;
    char type;
    char doctor[50];
    char time[8];
    char date[10];

}app;

/* ------------------------------------------System Function------------------------------------------ */

void testing()
{
    printf("lalalalala");
}

int escexit(char pkey)
{
    char reconfirm='Y';

    if(pkey==ESC)
        {
            do{
                if(!(toupper(reconfirm)=='Y' || toupper(reconfirm)=='N'))
                    invalid_msg();

                printf("\a\n\nAre you sure you want to exit the program? (Y/N)\nAny unsaved data will be lost\n");

                reconfirm = getch();
            }while(!(toupper(reconfirm)=='Y' || toupper(reconfirm)=='N'));

            if(toupper(reconfirm)=='Y')
            {
                cls();
                printf("Thanks for using.\a");
                exit(0);
            }
            else if(toupper(reconfirm)=='N')
                {
                cls();
                return 1;
                }
        }
}

int goback_previousmenu(char pkey)
{
    int result;

    if(pkey==BKSP)
        result = 1;

    return result;
}

void cls()
{
    system("cls");
}

void invalid_msg()
{
    printf("\aInvalid Input\nPlease try again\n\n");
}

void error_msg()
{

    cls();
    printf("\aError! Please contact Maximus Ooi!");
    exit(1);
}

/* ------------------------------------------Validation Function------------------------------------------ */

int selection_limiter(int type, int upper_limit, int lower_limit)   //Allow users to interact with the system by pressing respective key, BACKSPACE and ESC without carriage return.
{
    int goback_check = 0;
    int exit_check = 0;

    char input = '1';

    do{
        input = getch();

        exit_check = escexit(input);        //Check whether input key is ESC

        if(exit_check==1)
            return 0;

        goback_check = goback_previousmenu(input);      //Check whether input is BACKSPACE

        if ((type==0 || type==3 || type==4) && goback_check==1)     //Special outcome for BACKSPACE in type 0, 3, 4
            {
            printf("\a");
            break;
            }

     }while(!(input>=lower_limit && input<=upper_limit));

    if(type!=0)             //Condition type, 0 for only BACKSPACE & ESC; 1 for user type; 2 for action type; 3 for action; 4 for search option
    {
        if(type==1)
            usertype = input;
        else if(type==2)
            actiontype = input;
        else if(type==3)
            action = input;
        else if(type==4)
            search_choice = input;
        else
            error_msg();
    }

     return goback_check;
}

char *data_entry(int type, int size_limit)  //Limit user input with ASCII codes, type 1 for unmasked, type 2 for masked
{
    char input[30], p=' ' ;
    int i=0;

    while(i<=size_limit)
    {
        input[i] = getch();
        p = input[i];

        if(i==size_limit)
        {
            if(p==ENTER)
                break;
            else if((p>=48 && p<=57)||(p>=65 && p<=90)||(p>=97 && p<=122))
                {
                i--;
                printf("\b \b");
                }
        }

        if(p!=13 && p!='\b' && !((p>=48 && p<=57)||(p>=65 && p<=90)||(p>=97 && p<=122)))
        {
            p='\0';
        }

        else if(p==ENTER)
        {
            p='\0';
            break;
        }

        else if(p==BKSP)
        {
            i--;
            if(i!=-1)
            {
                p='\0' ;
                printf("\b \b");
            }
            else
            {
                p='\0' ;
                i++;
            }
        }

        else
        {
            if(type==1)
                printf("%c", input[i]);
            else if(type==2)
                printf("*");
            else
                error_msg();
            i++ ;
        }
    }
    input[i] = '\0' ;

    return input;
}

int alpha_str_validation(char input[])
{
    int validation, i;

    for(i=0;i<(strlen(input));i++)
    {
        if(isalpha(input[i])||(isspace(input[i])))
            validation=1;
        else
        {
            validation=0;
            break;
        }
    }

    return validation;
}

int num_str_validation(char input[])
{
    int validation, i;

    for(i=0;i<(strlen(input));i++)
    {
        if(input[i]>=48 && input[i]<=57)
            validation=1;
        else
        {
            validation=0;
            break;
        }
    }

    return validation;
}

/* -----------------------------------------------Main---------------------------------------------------- */

int main()
 {
     int contcheck;
     system("COLOR 0B");

     printf("Welcome to Maximus Hospital.\n");
     system("pause");


     do{

        usertype_selection();
        contcheck=login_validation();
     }while(contcheck==1);
     usertype_nav();
 }

 /* ------------------------------------------Login Function------------------------------------------ */

void usertype_file_verification()
{
    switch(usertype)
    {
        case '1':
            fp = fopen("r_password.txt", "r+");
            break;
        case '2':
            fp = fopen("d_password.txt", "r+");
            break;
        case '3':
            fp = fopen("a_password.txt", "r+");
            break;
    }
}

void usertype_username_retrieval()
{
    if(fp!=NULL)
    {
        fscanf(fp, "%s %*s\n", user.username);
    }
    else
        error_msg();
}

void usertype_password_retrieval()
{
    if(fp!=NULL)
    {
        fscanf(fp, "%*s %s\n", user.password);
    }
}

int login_validation()
{
    char input_name[30], input_pass[30], action;

    int login, goback_check;

    do{
        usertype_file_verification();

        int checker=0;
        login =0;

        cls();

        printf("Username: ");
        fflush(stdin);
        strcpy(input_name, data_entry(1, sizeof(input_name)));
        printf("\nPassword: ");
        fflush(stdin);
        strcpy(input_pass, data_entry(2, sizeof(input_name)));

        while(!feof(fp))
        {
            usertype_username_retrieval();
            usertype_password_retrieval();
            if((strcmp(user.username, input_name)==0) && (strcmp(user.password, input_pass)==0))
            {
                checker=1;
                rewind(fp);
                break;
            }
        }

        if(checker==1)
            {
                fp2 = fopen("Login Log.txt", "a+");
                printf("\a\n\nLogin Successful!\n");
                time_t mytime;
                mytime = time(NULL);
                printf(ctime(&mytime));
                fprintf(fp2, "%s\t\t%s", user.username, ctime(&mytime));
                fclose(fp2);
                login=1;
            }
        else
                printf("\a\n\nLogin Failed");


            printf("\n\nPress any key to continue...\nPress BACKSPACE to go back to previous menu\nPress ESC to exit\n");
            goback_check = selection_limiter(0,127,0);

        if (goback_check==1)
            break;

        }while(login==0);

        fclose(fp);

        return goback_check;

}

/* ------------------------------------------Data Entry for Patient------------------------------------------ */

int pat_numofline_get()
{
    int i=1, checker=1;
    char ch;

    do{
        fp2=fopen("patients.txt", "r");

        if(fp2!=NULL)
        {
            while(!feof(fp2))
            {
                ch = fgetc(fp2);
                if (ch=='\n')
                    i++;
            }

            checker = 1;
        }

        else
            {
            fp=fopen("patients.txt", "w");
            fclose(fp);
            checker==0;
            }

        fclose(fp2);
    }while(checker==0);

    return i;
}

int pat_id_get()
{
 int i = pat_numofline_get();

 sprintf(pat.id, "PAT%04d", i);

 printf("Patient ID\t: %s", pat.id );

 return i;
}

void pat_firstname_get()
{
    int validation=0;

    do{
        fflush(stdin);
        printf("\nFirst Name\t: ");
        scanf("%[^\n]s", pat.first_name);
        validation = alpha_str_validation(pat.first_name);
    }while(validation==0);
}

void pat_lastname_get()
{
    int validation=0;

    do{
        fflush(stdin);
        printf("Last Name\t: ");
        scanf("%[^\n]s", pat.last_name);
        validation = alpha_str_validation(pat.last_name);
    }while(validation==0);
}

void pat_name_merge()   //Merge last name and first name together with delimiters
{
    int i;

    sprintf(pat.full_name, "%s$%s", pat.first_name, pat.last_name);

    for(i=0;i<strlen(pat.full_name);i++)
    {
        if (pat.full_name[i]==' ')
            pat.full_name[i]=95;
    }

}

void pat_gender_get()
{
    do{
        fflush(stdin);
        printf("Gender(M/F/O)\t: ");
        scanf("%c", &pat.gender);
    }while(!(toupper(pat.gender)=='M' || toupper(pat.gender)=='F' || toupper(pat.gender)=='O'));
}

void pat_age_get()
{
    int validation = 0;

    do{
        fflush(stdin);
        printf("Age\t\t: ");
        scanf("%d", &pat.age);
    }while(!(isdigit(pat.age)==0) || pat.age==0);
}

void pat_ic_get()
{
    int validation = 0;

    do{
        fflush(stdin);
        printf("IC No.\t\t: ");
        scanf("%s", pat.ic);
        validation = num_str_validation(pat.ic);
    }while(validation==0 || (strlen(pat.ic)!=12));
}

void pat_contact_get()
{
    int validation = 0;

    do{
        fflush(stdin);
        printf("Contact No.\t: ");
        scanf(" %s", pat.contact_no);
        validation = num_str_validation(pat.contact_no);
    }while(validation==0 || !(strlen(pat.contact_no)>=10 && strlen(pat.contact_no)<=11));
}

int patient_add()
{
    int goback_check = 0, i;

    do{
        cls();

        printf("Add Patient\n\n");

        i=pat_id_get();
        pat_firstname_get();
        pat_lastname_get();
        pat_gender_get();
        pat_age_get();
        pat_ic_get();
        pat_contact_get();

        pat_name_merge();


        if(i==1)
            fp = fopen("patients.txt", "w");
        else
            fp = fopen("patients.txt", "a+");

        fprintf(fp, "%s\t\t%s\t\t%c\t\t%d\t\t%s\t\t%s\n", pat.id, pat.full_name, pat.gender, pat.age, pat.ic, pat.contact_no);
        fclose(fp);

        printf("\n\nPress BACKSPACE to select another action\nPress ESC to exit");
        goback_check=selection_limiter(0, 0, 0);

    }while(goback_check==0);

    return goback_check;
}

/* ------------------------------------------Data Entry for Appointment------------------------------------------ */

int app_numofline_get()
{
    int i=1, checker=1;
    char ch;

    do{
        fp2=fopen("appointments.txt", "r");

        if(fp2!=NULL)
        {
            while(!feof(fp2))
            {
                ch = fgetc(fp2);
                if (ch=='\n')
                    i++;
            }

            checker = 1;
        }

        else
            {
            fp=fopen("appointments.txt", "w");
            fclose(fp);
            checker==0;
            }

        fclose(fp2);
    }while(checker==0);

    return i;
}

int app_id_get()
{
    int i = app_numofline_get();

    sprintf(app.app_id, "APP%04d", i);

    printf("\nAppointment ID\t: %s", app.app_id );

    return i;
}

void app_type_get()
{
    do{
        fflush(stdin);
        printf("\nType(N/S/H)\t: ");
        scanf("%c",&app.type);
    }while(!(toupper(app.type)=='N' || toupper(app.type)=='S' || toupper(app.type)=='H'));
}

void app_doctor_get()
{
    int validation=0;

    do{
        fflush(stdin);
        printf("Doctor\t\t: ");
        scanf("%[^\n]s", app.doctor);
        validation = alpha_str_validation(app.doctor);
    }while(validation==0);
}

void app_time_get()
{
    int validation = 0;

    do{
        fflush(stdin);
        printf("Time\t\t: ");
        scanf("%s", app.time);
        validation = num_str_validation(app.time);
    }while(validation==0 || (strlen(app.time)!=4));
}

void date_merger(int date, int month, int year)
{
    sprintf(app.date, "%d-%d-%d", date, month, year);
}

void app_date_get()
{
    int date, month, year;

        fflush(stdin);
        printf("Date\t\t: ");
        scanf("%d", &date);
        printf("Month\t\t: ");
        scanf("%d", &month);
        printf("Year\t\t: ");
        scanf("%d", &year);

    date_merger(date, month, year);
}

int appointment_add()
{
    int goback_check = 0, i, validation=0, date, month, year;
    char input_id[10], buffer[50];
    do{
        cls();
        fp=fopen("patients.txt", "r");
        if(fp!=NULL)
        {
            do
            {
                printf("Add Appointment\n\n");
                printf("Patient ID\t: ");
                fflush(stdin);
                strcpy(input_id, data_entry(1, 10));

                rewind(fp);

                while(!(feof(fp)))
                {
                    patient_info_retrieval(0);
                    if(strcmp(pat.id,input_id)==0)
                        {
                        validation=1;
                        break;
                        }
                }
            }while(validation==0);
        }
        else
            error_msg();

        fclose(fp);

        strcpy(app.pat_id,pat.id);
        strcpy(app.name, pat.full_name);
        app.gender=toupper(pat.gender);

        strcpy(buffer, name_splitter(app.name));

        printf("\n\nPatient ID\t: %s\nPatient Name\t: %s\nGender\t\t: %c\n", app.pat_id, buffer, app.gender);

        printf("\nAppointment Detail");
        i=app_id_get();
        app_type_get();
        app_doctor_get();
        app_date_get();
        app_time_get();

        date_merger(date, month, year);

        if(i==0)
            fp = fopen("appointments.txt", "w");
        else
            fp = fopen("appointments.txt", "a+");


        fprintf(fp, "%s\t\t%s\t\t%s\t\t%c\t\t%c\t\t%s\t\t%s\t\t%s\n", app.app_id, app.pat_id, app.name, app.gender, app.type, app.doctor, app.time, app.date);
        fclose(fp);

        printf("\n\nPress BACKSPACE to select another action\nPress ESC to exit");
        goback_check=selection_limiter(0, 0, 0);

    }while(goback_check==0);

    return goback_check;
}

int appointment_search()
{
    int goback_check;
    char keyword[10];

    cls();

    printf("Search Appointment\n\n");
    strcpy(keyword, search_id());

    fp=fopen("appointments.txt", "r");
    if(fp!=NULL)
    {
        while(!feof(fp))
        {
            appointment_info_retrieval(1);
            if(strcmp(app.app_id, keyword)==0)
            {
                appointment_info_print();
                break;
            }
        }
        fclose(fp);
    }
    else
    error_msg();


    do{
        printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
        goback_check = selection_limiter(0, 0 , 0);
    }while(goback_check==0);

    return goback_check;
}


/* ------------------------------------------Data Modification & Display for Patient------------------------------------------ */

char *name_splitter(char input[])       //Remove delimiters in name
{
    int i;
    char buffer[50];

    strcpy(buffer,input);
    for(i=0;i<strlen(buffer);i++)
    {
        if(buffer[i]==95 || buffer[i]==36)
            buffer[i]=' ';
    }

    return buffer;
}

void patient_info_retrieval(int type) //type determine whether delimiters are added or not
{
    char buffer[10];

    fscanf(fp, "%s %s %c %d %s %s\n", pat.id, pat.full_name, &pat.gender, &pat.age, pat.ic, pat.contact_no);
    if(type!=0)
    strcpy(pat.full_name, name_splitter(pat.full_name));
}

void patient_info_print()
{
    printf("\n\nPatient ID\t: %s\nName\t\t: %s\nGender\t\t: %c\nAge\t\t: %d\nIC No.\t\t: %s\nContact No.\t: %s\n\n", pat.id, pat.full_name, toupper(pat.gender), pat.age, pat.ic, pat.contact_no);
}

int patient_view()
{
    int goback_check;

    cls();

    printf("View Patients\n");

    fp=fopen("patients.txt", "r");
    if(fp!=NULL)
    {
       while(!feof(fp))
       {
           patient_info_retrieval(1);
           patient_info_print();
       }

       fclose(fp);

       do{
        printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
        goback_check = selection_limiter(0, 0 , 0);
       }while(goback_check==0);
    }
    else
        error_msg();

    return goback_check;

}

int pat_line_locator(char input[])
{
    int i, validation=0;

    rewind(fp);

    for(i=0;(!feof(fp));i++)
    {
        fscanf(fp, "%s %*s %*c %*d %*s %*s\n", pat.id);
        if(strcmp(pat.id, input)==0)
            {
            validation=1;
            break;
            }
    }
    if(validation==1)
        return i;
    else
        return -1;
}
int patient_modify()
{
    char modify_target[10];
    int target_line, goback_check;

    FILE *fp;
    fp = fopen("patients.txt", "r");

    do
    {
    cls();
    printf("Modify Patient\n\n");
    fflush(stdin);
    strcpy(modify_target, search_id());
    target_line = pat_line_locator(modify_target);
    }while(target_line<0);

        if(fp!=NULL)
        {
            char confirm;

            rewind(fp);

            if(target_line!=-1)
            {
                printf("\nConfirm Edit? (Y/N)");
                confirm = getchar();

                if(toupper(confirm)=='Y')
                {
                    char words[1024];
                    char *buffer;
                    char *ptr;
                    int  line_counter = 0;
                    int  checker = 0;

                    buffer=(char *)malloc(1024%sizeof(char));
                    memset(buffer,0, 1024*sizeof(char));
                    ptr=buffer;


                    while(fgets(words, 1024, fp) != NULL)
                    {
                        line_counter++;
                        if(line_counter != target_line)
                        {
                            strcpy(ptr, words);
                            ptr +=strlen(words);
                        }
                        else if(line_counter == target_line)
                             {
                                char new_line[1024], buffer2[20];

                                cls();
                                fflush(stdin);

                                printf("Modify Patient\n");
                                fscanf(fp, "%s" , pat.id);
                                pat_firstname_get();
                                pat_lastname_get();
                                pat_gender_get();
                                pat_age_get();
                                pat_ic_get();
                                pat_contact_get();

                                pat_name_merge();


                                sprintf(buffer2,"%c\t\t%d", pat.gender, pat.age);

                                strcpy(new_line,pat.id);
                                strcat(new_line,"\t\t");
                                strcat(new_line,pat.full_name);
                                strcat(new_line,"\t\t");
                                strcat(new_line,buffer2);
                                strcat(new_line,"\t\t");
                                strcat(new_line,pat.ic);
                                strcat(new_line,"\t\t");
                                strcat(new_line,pat.contact_no);
                                strcat(new_line,"\n");

                                strcpy(ptr, new_line);
                                ptr +=strlen(new_line);
                            }

                }
                fclose(fp);

                fp=fopen("patients.txt","w");
                fprintf(fp, "%s", buffer);
                fclose(fp);

                printf("\n\n\aModify is completed.");
            }
        }
    }
    else
        error_msg();
        do{
            printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
            goback_check = selection_limiter(0, 0 , 0);
        }while(goback_check==0);
}

int patient_delete()
{
    char modify_target[10];
    int target_line, goback_check;

    FILE *fp;
    fp = fopen("patients.txt", "r");

    do
    {
    cls();
    printf("Delete Patient\n\n");
    fflush(stdin);
    strcpy(modify_target, search_id());
    target_line = pat_line_locator(modify_target);
    }while(target_line<0);

        if(fp!=NULL)
        {
            char confirm;

            rewind(fp);

            if(target_line!=-1)
            {
                printf("\nConfirm Delete? (Y/N)");
                confirm = getchar();

                if(toupper(confirm)=='Y')
                {
                    char words[1024];
                    char *buffer;
                    char *ptr;
                    int  line_counter = 0;
                    int  checker = 0;

                    buffer=(char *)malloc(1024%sizeof(char));
                    memset(buffer,0, 1024*sizeof(char));
                    ptr=buffer;

                    while(fgets(words, 1024, fp) != NULL)
                    {

                        if(line_counter != (target_line))
                        {
                            strcpy(ptr, words);
                            ptr +=strlen(words);
                        }
                        line_counter ++;
                    }
                    fclose(fp);

                    fp=fopen("patients.txt","w");
                    fprintf(fp, "%s", buffer);
                    fclose(fp);

                    printf("\n\nDelete completed!\a\n");
                }
            }
        }
        else
            error_msg();

        do{
            printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
            goback_check = selection_limiter(0, 0 , 0);
        }while(goback_check==0);
}
/* ------------------------------------------------Data Modification & Display for Appointment---------------------------*/

void appointment_info_retrieval(int type)
{
    fscanf(fp, "%s %s %s %c %c %s %s %s\n", app.app_id, app.pat_id, app.name, &app.gender, &app.type, app.doctor, app.time, app.date);
    if(type!=0)
        strcpy(app.name, name_splitter(app.name));
}

void appointment_info_print()
{
    printf("\n\nAppointment ID\t: %s\nPatient ID\t: %s\nName\t\t: %s\nGender\t\t: %c\nType\t\t: %c\nDoctor\t\t: %s\nDate\t\t: %s\nTime(24hrs)\t: %s\n", app.app_id, app.pat_id, app.name, toupper(app.gender), toupper(app.type), app.doctor, app.time, app.date);
}

int appointment_view()
{
    int goback_check;

    cls();

    printf("View Appointments\n");

    fp=fopen("appointments.txt", "r");
    if(fp!=NULL)
    {
        while(!feof(fp))
        {
            fflush(stdin);
            appointment_info_retrieval(1);
            fflush(stdin);
            appointment_info_print();
        }

        fclose(fp);

       do{
        printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
        goback_check = selection_limiter(0, 0 , 0);
       }while(goback_check==0);
    }
    else
        error_msg();

    return goback_check;
}

int app_line_locator(char input[])
{
    int i, validation=0;

    rewind(fp);

    for(i=0;(!feof(fp));i++)
    {
        fscanf(fp, "%s %*s %*s %*c %*c %*s %*s %*s\n", app.app_id);
        if(strcmp(app.app_id, input)==0)
            {
            validation=1;
            break;
            }
    }
    if(validation==1)
        return i;
    else
        return -1;
}

int appointment_modify()
{
    char modify_target[10];
    int target_line, goback_check;

    FILE *fp;
    fp = fopen("appointments.txt", "r");

    do
    {
    cls();
    printf("Modify Appointment\n\n");
    fflush(stdin);
    strcpy(modify_target, search_id());
    target_line = app_line_locator(modify_target);
    }while(target_line<0);

        if(fp!=NULL)
        {
            char confirm;

            rewind(fp);

            if(target_line!=-1)
            {
                printf("\nConfirm Edit? (Y/N)");
                confirm = getchar();

                if(toupper(confirm)=='Y')
                {
                    char words[1024];
                    char *buffer;
                    char *ptr;
                    int  line_counter = 0;
                    int  checker = 0;

                    buffer=(char *)malloc(1024%sizeof(char));
                    memset(buffer,0, 1024*sizeof(char));
                    ptr=buffer;


                    while(fgets(words, 1024, fp) != NULL)
                    {
                        line_counter++;
                        if(line_counter != target_line)
                        {
                            strcpy(ptr, words);
                            ptr +=strlen(words);
                        }
                        else if(line_counter == target_line)
                             {
                                char new_line[1024], buffer2[20];

                                cls();
                                fflush(stdin);

                                printf("Modify Appointment\n");
                                fscanf(fp, "%s %s %s %c", app.app_id, app.pat_id, app.name, &app.gender);
                                app_type_get();
                                app_doctor_get();
                                app_date_get();
                                app_time_get();

                                sprintf(buffer2,"%c\t\t%d", app.gender, app.type);

                                strcpy(new_line,app.app_id);
                                strcat(new_line,"\t\t");
                                strcat(new_line,app.pat_id);
                                strcat(new_line,"\t\t");
                                strcat(new_line,buffer2);
                                strcat(new_line,"\t\t");
                                strcat(new_line,app.doctor);
                                strcat(new_line,"\t\t");
                                strcat(new_line,app.date);
                                strcat(new_line,"\t\t");
                                strcat(new_line,app.time);
                                strcat(new_line,"\n");

                                strcpy(ptr, new_line);
                                ptr +=strlen(new_line);
                            }

                }
                fclose(fp);

                fp=fopen("appointments.txt","w");
                fprintf(fp, "%s", buffer);
                fclose(fp);

                printf("\n\n\aModify is completed.");
            }
        }
    }
    else
        error_msg();
        do{
            printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
            goback_check = selection_limiter(0, 0 , 0);
        }while(goback_check==0);
}

int appointment_delete()
{
    char modify_target[10];
    int target_line, goback_check;

    FILE *fp;
    fp = fopen("appointments.txt", "r");

    do
    {
    cls();
    printf("Delete Patient\n\n");
    fflush(stdin);
    strcpy(modify_target, search_id());
    target_line = app_line_locator(modify_target);
    }while(target_line<0);

        if(fp!=NULL)
        {
            char confirm;

            rewind(fp);

            if(target_line!=-1)
            {
                printf("\nConfirm Delete? (Y/N)");
                confirm = getchar();

                if(toupper(confirm)=='Y')
                {
                    char words[1024];
                    char *buffer;
                    char *ptr;
                    int  line_counter = 0;
                    int  checker = 0;

                    buffer=(char *)malloc(1024%sizeof(char));
                    memset(buffer,0, 1024*sizeof(char));
                    ptr=buffer;

                    while(fgets(words, 1024, fp) != NULL)
                    {

                        if(line_counter != (target_line))
                        {
                            strcpy(ptr, words);
                            ptr +=strlen(words);
                        }
                        line_counter ++;
                    }
                    fclose(fp);

                    fp=fopen("appointments.txt","w");
                    fprintf(fp, "%s", buffer);
                    fclose(fp);

                    printf("\n\nDelete completed!\a\n");
                }
            }
        }
        else
            error_msg();

        do{
            printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
            goback_check = selection_limiter(0, 0 , 0);
        }while(goback_check==0);
}
/* ------------------------------------------Search Function------------------------------------------------ */

char *search_name()
{
    int validation=0;
    char input[30];

    do{
        fflush(stdin);
        printf("Search Name\t: ");
        scanf("%[^\n]s", input);
        validation = alpha_str_validation(input);
    }while(validation==0);

    return  input;
}

char *search_id()
{
    char input[10];

    fflush(stdin);
    printf("Search ID\t: ");
    strcpy(input,data_entry(1,10));

    return  input;
}

int patient_search()
{
        int goback_check;
        char keyword[30];

        pat_search_selection();

        if(search_choice=='0')
            return 1;

        cls();

        printf("Search Patient\n\n");
        switch(search_choice)
        {
        case '1':
            strcpy(keyword, search_name());
            break;
        case '2':
            strcpy(keyword, search_id());
            break;
        default:
            error_msg();
        }

        fp=fopen("patients.txt", "r");
        if(fp!=NULL)
        {
            while(!feof(fp))
            {
                patient_info_retrieval(1);
                if(strstr(pat.full_name, keyword)!=NULL)
                    patient_info_print();
                if(strcmp(pat.id, keyword)==0)
                {
                    patient_info_print();
                    break;
                }
            }
            fclose(fp);
        }

        else
            error_msg();


        do{
            printf("\nPress BACKSPACE to go to previous menu\nPress ESC to exit.");
            goback_check = selection_limiter(0, 0 , 0);
        }while(goback_check==0);

        return goback_check;
}

/* ------------------------------------------Navigation Menu------------------------------------------------ */

void usertype_nav()
 {
    int contcheck=0;

    do
    {
        cls();

        switch(usertype)
        {
            case '1':

                actiontype_selection();
                contcheck = actiontype_nav();                                //based on action type, call menu
                break;
            case '2':
                actiontype_selection();
                contcheck = actiontype_nav();
                break;
            case '3':
                testing();
                break;
        }
    }while(contcheck==1);
 }

int actiontype_nav()
 {
        int contcheck = 0;

        do{
            cls();

            switch(actiontype)
            {
                case '1':
                    if(usertype=='1')
                    {
                        contcheck = pat_rec_action_selection();
                        if(contcheck==1)
                            return contcheck;
                        else
                           {
                            contcheck = pat_rec_action_nav();
                            break;
                           }
                    }
                    else if(usertype=='2')
                    {
                        contcheck = pat_doc_action_selection();
                        if(contcheck==1)
                            return contcheck;
                        else
                            contcheck = pat_doc_action_nav();
                            break;
                    }
                case '2':
                    if(usertype=='1')
                    {
                        contcheck = app_rec_action_selection();
                        if(contcheck==1)
                            return contcheck;
                        else
                           {
                            contcheck = app_rec_action_nav();
                            break;
                           }
                    }
                    else if(usertype=='2')
                    {
                        contcheck = app_doc_action_selection();
                        if(contcheck==1)
                            return contcheck;
                        else
                            {
                            contcheck = app_doc_action_nav();
                            break;
                            }
                    }
            }
        }while(contcheck==1);
    }

int pat_rec_action_nav()
{
    int contcheck = 0;

        cls();

    switch(action)
    {
        case '1':
            contcheck = patient_add();
            if(contcheck==1)
                return contcheck;
        case '2':
            contcheck = patient_view();
            if(contcheck==1)
                return contcheck;
            break;
        case '3':
            contcheck = patient_search();
            if(contcheck==1)
                return contcheck;
            break;
        case '4':
            contcheck = patient_modify();
            if(contcheck==1)
                return contcheck;
            break;
        case '5':
            contcheck = patient_delete();
            if(contcheck==1)
                return contcheck;
            break;
        default:
            error_msg();
    }
}

int app_rec_action_nav()
{
    int contcheck = 0;

    cls();
    switch(action)
    {
        case '1':
            contcheck = appointment_add();
            if(contcheck==1)
                return contcheck;
        case '2':
            contcheck = appointment_view();
            if(contcheck==1)
                return contcheck;
            break;
        case '3':
            contcheck = appointment_search();
            if(contcheck==1)
                return contcheck;
            break;
        case '4':
            contcheck = appointment_modify();
            if(contcheck==1)
                return contcheck;
            break;
        case '5':
            contcheck = appointment_delete();
            if(contcheck==1)
                return contcheck;
            break;
        default:
            error_msg();
    }
}

int pat_doc_action_nav()
{
    int contcheck = 0;

        cls();

    switch(action)
    {
        case '1':
            contcheck = patient_view();
            if(contcheck==1)
                return contcheck;
        case '2':
            contcheck = patient_search();
            if(contcheck==1)
                return contcheck;
            break;
        default:
            error_msg();
    }
}

int app_doc_action_nav()
{
    int contcheck = 0;

        cls();

    switch(action)
    {
        case '1':
            contcheck = appointment_view();
            if(contcheck==1)
                return contcheck;
        case '2':
            contcheck = appointment_search();
            if(contcheck==1)
                return contcheck;
            break;
        default:
            error_msg();
    }
}

/* --------------------------------------------Selection Menu------------------------------------------------------ */

void usertype_selection()
 {
    do
    {
        cls();
        printf("1. Receptionist\n2. Doctor\n\nPress respective key to select a type...\nPress ESC to exit\n");
        selection_limiter(1, 50, 49);
    }while(!(usertype>=49 && usertype<=50));
 }

void actiontype_selection()
 {
    do
    {
        cls();
        printf("1. Patient Management\n2. Appointment Management\n\nPress respective key to select an option...\nPress ESC to logout\n");
        selection_limiter(2, 50, 49);
    }while(!(actiontype>=49 && actiontype<=50));
 }

int pat_rec_action_selection()
{
    int goback_check;

    do
    {
        cls();
        printf("1. Add Patient\n2. View Patient\n3. Search Patient\n4. Modify Patient\n5. Delete Patient\n\nPress respective key to select an action...\nPress BACKSPACE to go to previous menu\nPress ESC to exit\n");
        goback_check = selection_limiter(3, 53, 49);
        if(goback_check==1)
            break;
    }while(!(action>=49 && action<=53));

    return goback_check;
}

int app_rec_action_selection()
{
    int goback_check;

    do
    {
        cls();
        printf("1. Add Appointment\n2. View Appointment\n3. Search Appointment\n4. Modify Appointment\n5. Delete Appointment\n\nPress respective key to select action...\nPress BACKSPACE to go to previous menu\nPress ESC to exit\n");
        goback_check = selection_limiter(3, 53, 49);
        if(goback_check==1)
            break;
    }while(!(action>=49 && action<=53));

    return goback_check;
}

int pat_doc_action_selection()
{
    int goback_check;

    do
    {
        cls();
        printf("1. View Patient\n2. Search Patient\n\nPress respective key to select an action...\nPress BACKSPACE to go to previous menu\nPress ESC to exit\n");
        goback_check = selection_limiter(3, 53, 49);
        if(goback_check==1)
            break;
    }while(!(action>=49 && action<=50));

    return goback_check;
}

int app_doc_action_selection()
{
    int goback_check;

    do
    {
        cls();
        printf("1. Add Appointment\n2. View Appointment\n3. Search Appointment\n4. Modify Appointment\n5. Delete Appointment\n\nPress respective key to select action...\nPress BACKSPACE to go to previous menu\nPress ESC to exit\n");
        goback_check = selection_limiter(3, 53, 49);
        if(goback_check==1)
            break;
    }while(!(action>=49 && action<=53));

    return goback_check;
}

void pat_search_selection()
{
    int goback_check;

    do
    {
        cls();
        printf("Search Patient\n\n1. Search with name\n2. Search with patient ID\n\nPress respective key to select action\nPress BACKSPACE to go to previous menu\nPress ESC to exit\n");
        goback_check = selection_limiter(4, 50, 49);
        if(goback_check==1)
            {
                search_choice='0';
                return;
            }
    }while(!(search_choice>=49 && search_choice<=50));
}