#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <dirent.h>
#include <sys/utsname.h>
#include <sys/sysinfo.h>
#include <X11/Xlib.h>
#include <X11/Xatom.h>
#include <unistd.h>
#include <sys/statvfs.h>



#define BUF_SIZE 50
#define SUPPORTED_OS "xadurm"
#define ARCH_BASED "axmr"
#define DEBIAN_BASED "du"
#define OS_TABLE "a:Arch|x:Artix|r:Arco|m:Manjaro|u:Ubuntu|d:Debian"


void read_line(char x);
static int count_files(DIR *package_dir);

static char *get_sys(void);
static char *get_kernel(void);
static char *get_uptime(void);
static char *get_RAM(void);
static char *get_packages(void);
static char *get_term(void);



char sys;
Display *display;







int main(){

  printf("\n");
  printf(" %s\n", get_sys());
  printf(" %s\n", get_kernel());
  printf(" %s\n", get_uptime());
  printf(" %s\n", get_packages());
  printf(" \x1b[37m \x1b[0m  %s\n", get_term());
  printf(" %s\n", get_RAM());
  printf("\n");

  return EXIT_SUCCESS;
}








void read_line(char x) {
    int c;
    while (( c = getchar()) != x && c != EOF) {}
}




void truncate_spaces(char *str) {
  int src = 0, dst = 0, index, i = -1;
  
  while(*(str + dst) == ' ') dst++;

    while(*(str + dst) != '\0') {
        *(str + src) = *(str + dst);
        if(*(str + (dst++)) == ' ')
            while(*(str + dst) == ' ') dst++;

        src++;
    }

    *(str + src) = '\0';

    i = 0;
    while(str[i] != '\0'){
        if(str[i] != ' ' && str[i] != '\t' && str[i] != '\n'){
            index= i;
      }
        i++;
    }


    str[index + 1] = '\0';
}




static int count_files(DIR *package_dir) {

   struct dirent * entry;
   int file_count = 0;

   while ((entry = readdir(package_dir)) != NULL) {
      if (entry->d_type == DT_DIR) {
         file_count++;
      }
   }
   closedir(package_dir);

   return file_count;
}




static char *get_sys(void) {

   char *name = malloc(BUF_SIZE);
   FILE *f_sys_name = fopen("/etc/issue", "rt");
   char *os_name = malloc(BUF_SIZE);

    if( f_sys_name == NULL ){ 
      fprintf(stderr, "\nCan't get os name\n");
      exit(EXIT_FAILURE);
    }


   fscanf(f_sys_name, "%s %*s", name);
   fclose(f_sys_name);
   truncate_spaces(name);

  
   if( !(sys = *(strstr(OS_TABLE, name) - 2)) ){
       fprintf(stderr, "\nUnsupported OS\n");
       exit(EXIT_FAILURE);
   }

  snprintf(os_name, BUF_SIZE, "\x1b[37m \x1b[0m  %s", name);


   free(name);
   return os_name;
}






static char *get_kernel(void){

   char *kern_name = malloc(BUF_SIZE);

   struct utsname u_info;
   uname(&u_info); 

   snprintf(kern_name, BUF_SIZE, "\x1b[37m \x1b[0m  %s", u_info.release);

   return kern_name;
}




static char *get_uptime(void){
    
   char *uptime = malloc(BUF_SIZE);
   unsigned int sec;
   short hr, min;
   struct sysinfo sys_info;

   sysinfo(&sys_info);

   sec = sys_info.uptime;
   hr  = (sec/60/60%24);
   min = (sec/60%60);

   snprintf(uptime, BUF_SIZE, "\x1b[37m \x1b[0m  %hd h, %hd min", hr, min);
   return uptime;
}




static char *get_packages(void){

   int pkg_count = 0;
   char *package_count = malloc(BUF_SIZE);


       if( strchr(ARCH_BASED, sys) )
         pkg_count = count_files(opendir("/var/lib/pacman/local"));

       else if( strchr(DEBIAN_BASED, sys) )
         pkg_count = count_files(opendir("/usr/bin")) + count_files(opendir("/sbin")); // still not sure where to look 



       else{
         printf("\n\n\aUnable to find package list\n\n");
         exit(EXIT_FAILURE);
       }

   snprintf(package_count, BUF_SIZE, "\x1b[37m \x1b[0m  %d", pkg_count);

      
   return package_count;
}




static char *get_RAM(void){

   float used_m, total_m;

   int total, shared, memfree, buffers, cached, reclaimable;

   char *ram_info = malloc(BUF_SIZE * 3);
   FILE *RAM = fopen("/proc/meminfo", "rt");


   char *line = NULL;
   size_t len;


    while (getline(&line, &len, RAM) != -1) {
        sscanf(line, "MemTotal: %d", &total);
        sscanf(line, "Shmem: %d", &shared);
        sscanf(line, "MemFree: %d", &memfree);
        sscanf(line, "Buffers: %d", &buffers);
        sscanf(line, "Cached: %d", &cached);
        sscanf(line, "SReclaimable: %d", &reclaimable);
    }

   fclose(RAM);
   free(line);


    used_m  = (float)(total + shared - memfree - buffers - cached - reclaimable) / (1024*1024);
    total_m = (float)total / (1024*1024);


   snprintf(ram_info, BUF_SIZE * 3, "\x1b[37m \x1b[0m  %.2f / %.2f GB", used_m, total_m);


   return ram_info;
}




static char *get_term(void) {
    unsigned char *prop;
    char *terminal = malloc(BUF_SIZE);

    if (display != NULL) {

    unsigned long _,
                  window = RootWindow(display, XDefaultScreen(display));
        Atom a,
             active = XInternAtom(display, "_NET_ACTIVE_WINDOW", True),
             class = XInternAtom(display, "WM_CLASS", True);

#define GetProp(property) \
        XGetWindowProperty(display, window, property, 0, 64, 0, 0, &a, (int *)&_, &_, &_, &prop);

        GetProp(active);
        window = (prop[3] << 24) + (prop[2] << 16) + (prop[1] << 8) + prop[0];
        free(prop);
        if(!window) goto terminal_fallback;
        GetProp(class);

#undef GetProp

        snprintf(terminal, BUF_SIZE, "%s", prop);
        free(prop);
    }

    else {
terminal_fallback:
        strncpy(terminal, getenv("TERM"), BUF_SIZE);

        if (strcmp(terminal, "linux") == 0) {
            strncpy(terminal, ttyname(STDIN_FILENO), BUF_SIZE);
        }
    }

    return terminal;
}