#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <string.h>
#include <unistd.h>
#include <wait.h>
int *i_log, n,k=0;
FILE *f_log;
DIR *dir_log;
void backuper(char *s1,char *s2)
{
    DIR *d1,*d2,*dir_cp;
    struct dirent *dir;
    int i,bull,g=0;
    char *sum,*sum_cp;
    pid_t pid;
    d1=opendir(s1);
    if(d1==NULL)
    {
        printf("%s - unable to read directory\n",s1);
    }
    else
    {
        mkdir(s2,0777);
        d2=opendir(s2);
        sum=malloc(strlen(s1)+256*sizeof(char));
        sum_cp=malloc(strlen(s2)+256*sizeof(char));
        while((dir=readdir(d1))!=NULL)
        {
            strcpy(sum,s1);
            strcpy(sum_cp,s2);
            bull=1;
            if(dir->d_type==DT_DIR)
            {
                if((strcmp(dir->d_name,"..")!=0)&&(strcmp(dir->d_name,"."))!=0)
                {
                    strcat(sum,dir->d_name);
                    strcat(sum,"/");
                    strcat(sum_cp,dir->d_name);
                    strcat(sum_cp,"/");
                    if((dir_cp=opendir(sum_cp))==NULL)
                    {
                        mkdir(sum_cp,0777);
                    }
                    else
                    {
                        closedir(dir_cp);
                    }
                    backuper(sum,sum_cp);
                }
            }
            else
            {
                for(i=0;i<n;i++)
                {
                    if((dir->d_ino)==i_log[i])
                    {
                        bull=0;
                    }
                }
                if(bull)
                {
                    pid=fork();
                    if(pid==0)
                    {
                        strcat(sum,dir->d_name);
                        g=execl("/bin/cp","cp",sum,s2,NULL);
                        exit(0);
                    }
                    else
                    {
                        waitpid(pid,NULL,0);
                    }
                    fprintf(f_log,"%d\n",(int)dir->d_ino);
                    pid=fork();
                    if(pid==0)
                    {
                        strcat(sum_cp,dir->d_name);
                        execl("/bin/gzip","gzip","-f",sum_cp,NULL);
                        exit(0);
                    }
                    else
                    {
                        waitpid(pid,NULL,0);
                    }
                    k++;
                }
            }
        }
        closedir(d1);
        free(sum);
        free(sum_cp);
    }
}

int main(int argc, char *argv[])
{
    int R;
    char *c_log,*s1;
    DIR *d2;
    char *s2;
    d2=opendir(argv[2]);
    if(d2==NULL)
    {
        if(mkdir(argv[2],0777)!=0)
        {
            printf("Unable to write there!\n");
        }
    }
    R=strlen(argv[1]);
    if(argv[1][R]!='/')
    {
        s1=malloc(R*sizeof(char)+2);
        strcpy(s1,argv[1]);
        s1[R]='/';
        s1[R+1]=0;
    }
    else
    {
        s1=malloc(R*sizeof(char));
        strcpy(s1,argv[1]);
    }
    R=strlen(argv[2]);
    if(argv[2][R]!='/')
    {
        s2=malloc(R*sizeof(char)+6);
        strcpy(s2,argv[2]);
        s2[R]='/';
        s2[R+1]=0;
    }
    else
    {
        s2=malloc(R*sizeof(char)+4);
        strcpy(s2,argv[2]);
    }
    n=strlen(s2);
    c_log=malloc(sizeof(char)*(n+8));
    strcpy(c_log,s2);
    c_log[n]='l';
    c_log[n+1]='o';
    c_log[n+2]='g';
    c_log[n+3]='/';
    c_log[n+4]=0;
    if((dir_log=opendir(c_log))==NULL)
    {
        mkdir(c_log,0777);
    }
    else
    {
        closedir(dir_log);
    }
    c_log[n+4]='l';
    c_log[n+5]='o';
    c_log[n+6]='g';
    c_log[n+7]=0;
    n=0;
    if((f_log=fopen(c_log,"r"))!=NULL)
    {
        printf("found old log\n");
        while((fscanf(f_log,"%d",&R)!=EOF))
        {
            n++;
        }
        fclose(f_log);
        i_log=malloc(n*sizeof(int));
        n=0;
        f_log=fopen(c_log,"r");
        while((fscanf(f_log,"%d",&i_log[n]))!=EOF)
        {
            n++;
        }
        fclose(f_log);

    }
    f_log=fopen(c_log,"a");
    if(f_log==NULL)
    {
        printf("Unable to write in destination directory\n");
        exit(1);
    }
    R=strlen(s2);
    s2[R]='z';
    s2[R+1]='i';
    s2[R+2]='p';
    s2[R+3]='/';
    s2[R+4]=0;
    backuper(s1,s2);
    fclose(f_log);
    closedir(d2);
    printf("Copied and zipped elements - %d\n",k);
    return 0;
}