#include<stdio.h>
#include<conio.h>
#include<string.h>
#include<stdlib.h>
#include<math.h>
#define Student struct Stud
void add(FILE * fp); //to add to list
void display(FILE * fp);//display whole list
void searchRecord(FILE *fp);//find a particular record
void command(char ch,int n);//printing a character ch n times
void title();//printing head line for each screen
struct Stud
{
    int class;
    char name[100];
    int id;
    char fname[100];
    char mname[100];
    char mobile[13];
    float sgpa[3];
    float cgpa;
};


int main()
{
    FILE * fp;

    int option;
    char another;

    if((fp=fopen("studentInfo.txt","rb++"))==NULL)
    {
        if((fp=fopen("studentInfo.txt","wb++"))==NULL)
        {
            printf("can't open file");
            return 0;
        }
    }
    title();
    printf("\n\t\tpress any key to continue");
    getch();

    while(1)
    {
        title();
        printf("\n\t");
        command('-',64);
        printf("\n\n\t\t\t1. ADD Student");
        printf("\n\n\t\t\t2. DISPLAY Student LIST");
        printf("\n\n\t\t\t3. Search Record");
        printf("\n\n\t\t\t0. EXIT");
        printf("\n\n\t\tEnter Your Option :--> ");
        scanf("%d",&option);
        switch(option)
        {
        case 0:
            return 1;
            break;
        case 1:
            add(fp);
            break;
        case 2:
            display(fp);
            break;
        case 3:
            searchRecord(fp);
            break;
        default:
            printf("\n\t\tYou Pressed wrong key");
            printf("\n\t\tProgram terminated");
            getch();
            exit(0);

        }
    }
    return 1;

}
//----printing character ch at n times ------

void command(char ch,int n)
{
    while(n--)
    {
        putchar(ch);
    }
}

//-----Printing Head Line of the program -----

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

    printf("\n\n\t");
    command('*',16);
    printf("[STUDENT] [INFORMATION] [SYSTEM]");
    command('*',16);
    printf("\n");
}


// ==========ADDING NEW RECORD==========================

void add(FILE * fp)
{
    title();

    char another='y';
    Student s;
    int i;
    float cgpa;

    fseek(fp,0,SEEK_END);
    while(another=='y'||another=='Y')
    {
        printf("\n\n\t\tEnter class number \t");
        scanf("%d",&s.class);

        printf("\n\n\t\tEnter id number \t");
        scanf("%d",&s.id);

        printf("\n\n\t\tEnter Full Name of Student\t");
        fflush(stdin);
        fgets(s.name,100,stdin);
        s.name[strlen(s.name)-1]='\0';

        printf("\n\n\t\tEnter Full Name of Student's Fathers's name\t");
        fflush(stdin);
        fgets(s.fname,100,stdin);
        s.fname[strlen(s.fname)-1]='\0';

        printf("\n\n\t\tEnter Full Name of Student's Mother's name\t");
        fflush(stdin);
        fgets(s.mname,100,stdin);
        s.mname[strlen(s.mname)-1]='\0';

        printf("\n\n\t\tEnter Student's Mobile number\t");
        fflush(stdin);
        fgets(s.mobile,13,stdin); //fgets takes an extra \n character as input
        s.mobile[strlen(s.mobile)-1]='\0';

        printf("\n\n\tEnter SGPA for 3 semesters\n\t");
        for(i=0,cgpa=0; i<3; i++)
        {
            scanf("%f",&s.sgpa[i]);
            cgpa+=s.sgpa[i];

        }

        cgpa/=3.0;
        s.cgpa=cgpa;

        fwrite(&s,sizeof(s),1,fp);

        printf("\n\n\t\tWant to enter another student info (Y/N)\t");
        fflush(stdin);
        another=getchar();
    }
}

//====================DISPLAY THE LIST =================
void display(FILE * fp)
{
    title();
    Student s;
    int i,siz=sizeof(s);

    rewind(fp);

    while((fread(&s,siz,1,fp))==1)
    {
        printf("\n\n\t\tCLASS : %d",s.class);
        printf("\n\n\t\tID : %d",s.id);
        printf("\n\t\tNAME : %s",s.name);
        printf("\n\n\t\tFather's Name : %s",s.fname);
        printf("\n\n\t\tMOther's Name : %s",s.mname);
        printf("\n\n\t\tMOBILE : %s",s.mobile);
        printf("\n\n\tSGPA: ");

        for(i=0; i<3; i++)
            printf("| %.2f |",s.sgpa[i]);
        printf("\n\n\t\tCGPA : %.2f\n\t",s.cgpa);
        command('-',65);
    }
    printf("\n\n\n\t");
    command('*',65);
    printf("\n\n\t");
    system("pause");
}

void searchRecord(FILE *fp)
{
    title();

    int tempId,flag,siz,i,tempclass;
    Student s;
    char another='y';

    siz=sizeof(s);

    while(another=='y'||another=='Y')
    {
        printf("\n\n\tEnter Class Number of a Student to search the record : ");
        scanf("%d",&tempclass);

        rewind(fp);

        while((fread(&s,siz,1,fp))==1)
        {
            if(s.class==tempclass)
            {
                printf("\n\n\tEnter ID Number of a Student to search the record : ");
                scanf("%d",&tempId);

                rewind(fp);
                while((fread(&s,siz,1,fp))==1)
                {
                   if(s.id==tempId)
                      {
                          flag=1;
                          break;
                      }
                }
                break;
            }
        }

        if(flag==1)
        {
            printf("\n\t\tNAME : %s",s.name);
            printf("\n\n\t\tFather's name : %s",s.fname);
            printf("\n\n\t\tMother's name : %s",s.mname);
            printf("\n\n\t\tMobile : %s",s.mobile);
            printf("\n\n\tSGPA: ");

            for(i=0; i<3; i++)
                printf("| %.2f |",s.sgpa[i]);
            printf("\n\n\t\tCGPA : %.2f\n\t",s.cgpa);
            command('-',65);

        }
        else
            printf("\n\n\t\t!!!! ERROR RECORD NOT FOUND !!!!");


        printf("\n\n\t\tWant to enter another search (Y/N)");
        fflush(stdin);
        another=getchar();
    }
}