/*
 * Copyright 2016-2017 CHASE MARSH
 *
 */

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

//MACROS: CONSTANTS
#define MAX_SIZE 256

//global variables for number of directories, and sum.
int counter = 0;
long sum = 0;

void sortUtility(struct dirent *list, int size) { //this method is supposed to perform an insertion sort
    int i,j;
    struct dirent *temp;

    for(i = 1; i < size; i++) {
        j = i - 1;
        while (j >= 0 && strcasecmp(list[j+1].d_name, list[j].d_name) > 0) {
            temp = &list[j+1];
            list[j + 1] = list[j];
            list[j] = *temp;
            j--;
        }
    }

}

int getSize(char const *sizeToGet) {//this gets the size and prints the correct suffix of a directory
            struct stat sizes;

            stat(sizeToGet, &sizes);

            if(sizes.st_size < 1024) {
                printf("%u", sizes.st_size);
                printf("B\t");
                sum += sizes.st_size;
            }
            else if(sizes.st_size < (1024*1024)) {
                sizes.st_size = sizes.st_size / 1024;
                printf("%u", sizes.st_size);
                printf("K\t");
                sum += sizes.st_size;
            }
            else {
                printf("%u", sizes.st_size);
                printf("MB\t");
                sum += sizes.st_size;
            }
            return sizes.st_size;

}

void formatSize(long size) {//this method formats the suffic based on an integer provided
            if(size < 1024) {
                printf("%d", size);
                printf("B\t");

            }
            else if(size < (1024*1024)) {
                printf("%d", size/1024);
                printf("K\t");
            }
            else {
                printf("%d", size/(1024*1024));
                printf("MB\t");
            }

}

void listFiles(char const *directory) {//method to recursively list the directories within the current directory


    DIR *dir = opendir(directory);
    struct dirent *names;
    struct dirent *namelist[1024];
    char *cwd;

    if(dir == NULL) { //if there is nothing then just exit
        return;
    }

        while ((names = readdir(dir)) != NULL) {
            if(!(strcmp(names->d_name, ".") == 0)) { //take care of the "." and ".." directories
                if(!(strcmp(names->d_name, "..") == 0)) {
                    counter++;

                    if(names->d_type == DT_DIR) { //takes care of child directories

                        cwd = malloc(strlen(directory) + strlen(names->d_name) + 2); //allocate memory and add path
                        strcpy(cwd, directory);
                        strcat(cwd, "/");
                        strcat(cwd, names->d_name);

                        listFiles(cwd);//recursive call to the method

                        free(cwd);//free the memory used
                    }

                    namelist[counter] = names->d_name; //put all of the directory names into an array
                    sortUtility(names, counter);//call sort method

                    getSize(names->d_name); //print the sizes
                    printf(".%s/", directory);//print the path
                    printf("%s\n", names->d_name);//print the actual directory or file name

                }
            }
            counter++; //increase counter of number of directories
        }


        closedir(dir); //close the current working directory

}

//main entry point - starts in current working directory
int main() {
        char startDirectory[MAX_SIZE];

        getcwd(startDirectory, sizeof(startDirectory));
        listFiles(startDirectory);
        formatSize(sum); //calls the formatSize method on sum to get the suffix properly formatted
        printf(".");

        return 0;
}