#include <stdio.h>
#include <string.h>
#include <stdlib.h>

void writeNamesToFile(char []);
void writerollToFile(char []);
void saveDataToStructure();
void takeInputs();
void showAll();

FILE *fp;
int strucsize=0;
int x,i;



struct student
{
    char names[100];
    int roll;
    char dept;
    double cgpa;
} info[100];


int main()
{
    ///file theke data niye structure a save korbe...program er surutei ei kaj korbe
    saveDataToStructure();
    ///

    ///choice nibe j user ki korte chaay...eikhane search aro habi jabi add korba


    while(1)
    {
        printf("\n\n\nWhat do you want to do?\n");
        printf("1. Add Data");
        printf("\n2.Show Data");
        printf("\n3.Search info By roll\n");
        int choice;
        scanf("%d",&choice);

        if(choice==1)
        {
            fflush(stdin); ///gtoklker porblem taa....jeno gets ekta skip naa kore
            takeInputs();
            saveDataToStructure();///input niye toh file a rakhlam...oita abr structure a load kore rakhbo
        }
        else if(choice==2)
        {
            showAll();
        }
        else if(choice==3)
        {
            search();
        }
    }



}


///structure er sob element show korbe...bujhar e kotha
void showAll()
{
    int i=0;
    for(i=0; i<strucsize; i++)
    {
        printf("-----%d-----",i+1);
        printf("\nStudent name: %s",info[i].names);
        printf("Number: %d",info[i].roll);
        printf("\n\n");
    }
}


///input niye oita file a save korbe
void takeInputs()
{
    printf("Type exit to stop taking data\n");
    char names[100];
    char num[100];
    while(1)
    {
        printf("Enter names: ");
        gets(names);
        if(strcmp(names,"exit")==0)
            break;
        else
        {
            printf("Enter roll: ");
            gets(num);
            if(strcmp(names,"exit")==0) ///same check jodi exit likhe r input nibe na
            {
                break;
            }
            else
            {
                ///prottek taar sathe ekta newline add kore save korbo file a
                writeNamesToFile(strcat(names,"\n"));
                writerollToFile(strcat(num,"\n"));
            }
        }
    }
}

void writeNamesToFile(char str[])
{
    fp=fopen("names.txt","a+");
    fprintf(fp,str);
    fclose(fp);
}
void writerollToFile(char str[])
{
    fp=fopen("roll.txt","a+");
    fprintf(fp,str);
    fclose(fp);
}
void writedepttofiles(char str[])
{
    fp=fopen("dept.text","a+");
    fprintf(fp,str);
    fclose(fp);
}
void writeCGPAtofiles(char str[])
{
    fp=fopen("cgpa","a+");
    fprintf(fp,str);
    fclose(fp);
}

void saveDataToStructure()

{

    FILE *fproll,*fpnames,*fpdept,*fpcgpa;

    fproll=fopen("roll.txt","r+");
    fpnames=fopen("names.txt","r+");
    fpdept=fopen("dept.txt","r+");
    fpcgpa=fopen("cgpa","r+");

    strucsize=0;
    char ch;
    char numstr[10][100];
    int i=0,j=0;
    ///roll save
    while((ch=fgetc(fproll))!=EOF)
    {
        numstr[i][j]=ch;
        j++;
        if(ch=='\n')
        {
            info[i].roll=atoi(numstr[i]);
            i++;
            j=0;
            strucsize++;
        }
    }

    i=0;
    j=0;

    ///name save
    while((ch=fgetc(fpnames))!=EOF)
    {
        info[i].names[j]=ch;
        if(ch=='\n')
        {
            i++;
            j=0;
        }
    }
    i=0;
    j=0;
    /// dept save
      while((ch=fgetc(fpdept))!=EOF)
    {
        info[i].dept[j]=ch;
        j++;
        if(ch=='\n')
        {
            i++;
            j=0;
        }
    }
    ///cg save
    char cgstr[10][100];
    while((ch=fgetc(fpcgpa))!=EOF)
    {
        cgstr[i][j]=ch;
        j++;
        if(ch=='\n')
        {
            info[i].roll=atoi(cgstr[i]);
            i++;
            j=0;
            strucsize++;
        }
    }
    fclose(fproll);
    fclose(fpnames);
    fclose(fpdept);
    fclose(fpcgpa);
}

void search(char roll)
{
    printf("Enter roll to search: \n");
    scanf("%d",&x);
    for(i=0;i<strucsize;i++)
    {
        if(x==info[i].roll)
        {
            printf("%s\t %d\n%s\t%lf",info[i].names,info[i].roll,info[i].dept,info[i].cgpa);
        }
    }

}