#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <unistd.h>
#include <dirent.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <string.h>
#include <ctype.h>

int counter = 0, fd, digits = 0, low = 0, up = 0, n;

int parse(char *ch, char *dirName) {
    char character = *ch;
    DIR *dir;

    if ((dir = opendir(dirName)) == NULL) {
        printf("Error at opendir().");
        exit(1);
    }

    struct dirent *d;
    struct stat st;
    char path[50], c;

    while ((d = readdir(dir))) {
        if ((strcmp(d->d_name, ".") == 0) || (strcmp(d->d_name, "..") == 0))
            continue;
        snprintf(path, 50, "%s/%s", dirName, d->d_name);
        printf("%s\n", path);
        if (lstat(path, &st) == -1) {
            printf("Error at lstat().");
            exit(2);
        }
        if (S_ISDIR(st.st_mode)) {
        parse(ch, path);
        }
        if (S_ISREG(st.st_mode)) {
            if((fd = open(path, O_RDONLY)) < 0) {
            printf("Error opening input file\n");
            exit(3);
            }
        while((n = read(fd, &c, sizeof(char))) > 0) {
        if(c == character)
            counter ++;
        if(isdigit(c))
            digits ++;
        if(islower(c))
            low ++;
        if(isupper(c))
            up ++;
        }
        close(fd);
        }
    }
    printf("Digits: %d\nLower: %d\nUpper: %d\nCharacter: %d\n", digits, low, up, counter);
    closedir(dir);
    return 0;
}

int main (int argc, char *argv[]) {
    if (argc != 3) {
        printf("Usage: Program <%s> char directory", argv[0]);
        exit(0);
    }
    parse(argv[1], argv[2]);
    return 0;
}