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

#define MAX_LINE 64

/***
** Structure definition
***/
typedef struct _student {
  char* name;
  int id;
  struct _student* next;
} Student;

typedef struct _dorm {

  char* name;
  int dormNum;
  int numStudents;

  Student *studentList;
  struct _dorm* next;
} Dorm;

/***
** One global variable
***/
Dorm *dormListHead = NULL;

/***
** Function prototypes: We have three set of functions
** 1. Part I  : Functions you have to write
** 2. Part II : Functions that you can use for debugging
** 3. Part III: Functions that you dont have to touch
***/
/* Functions that you need to write */
void addDorm(char* name, int dormNum);
void addStudent(char* name, int id);
void graduate(int id);
void move(char* name, int id, int dormNum);

/* Function prototypes that you can use for debugging */
void printStudentList(Student* listHead);
void printDorms();

/* Other function prototypes that you dont have to touch */
void usage();
int readDormFile(char* dormFileName);
int readStudentFile(char* studentFileName);
void releaseMemory();

/* Main function */
int main(int argc, char* argv[]){

  if(argc != 3) {
    usage();
    return -1;
  }

  readDormFile(argv[1]);
  readStudentFile(argv[2]);

  printDorms();

  /* Release all the memory allocated */
  releaseMemory();
  return 0;
}

/**
** COMPLETE THE BELOW FUNCTIONS
**/
void addDorm(char* name, int dormNum){

  /** TODO:
  ** 1. Add a Dorm with 'name' (and 'dormNum') to the 'head' of the linked list pointed
  ** by 'dormListHead'
  ** 2. Set the 'numStudents' to zero
  **/
}

void addStudent(char* name, int id){

  /** TODO:
  ** 1. Add the student with 'name' (and 'id') to the least populated dorm
  ** 2. Add the student at the tail of the studentList of the Dorm.
  **/
}

void graduate(int id){
  /** TODO:
  ** 1. Find the dorm to which the student with 'name' and 'id' belongs
  ** 2. Remove that student from the studentList of the dorm
  **/
}

void move(char* name, int id, int dormNum){

  /** TODO:
  ** Move a student with 'name' and 'id' to the new dorm
  **/
}

/** 
**    UTILITY FUNCTIONS
** Do not modify below this line 
**/
void usage(){

  fprintf(stderr, "Usage: dorm <dormFile> <studentFile>\n");
}


int readDormFile(char* dormFileName){

  char line[MAX_LINE];
  char name[MAX_LINE];
  char* str;
  int id;
  FILE* f;

  if(dormFileName == NULL) {
    printf("Dorm file name is invalid\n");
    return -1;
  }

  f = fopen(dormFileName, "r");
  if(f == NULL) {
    printf("Dorm file (%s) is not present\n", dormFileName);
    return -1;
  }

  while(( str = fgets(line, MAX_LINE, f)) != NULL) {

    int len = strlen(line);
    if(len > 1 && line[len-1] == '\n') {
      line[len-1] = '\0';
      len = strlen(line);
      if(len > 0) {
        sscanf(line, "%d %s",&id, name);
        addDorm(name, id);
      }
    }
  }
  fclose(f);
  return 0;
}

int readStudentFile(char* studentFileName){

  char line[MAX_LINE];
  char name[MAX_LINE];
  char* str;
  int id;
  FILE* f;

  if(studentFileName == NULL) {
    printf("Student file name is invalid\n");
    return -1;
  }

  f = fopen(studentFileName, "r");
  if(f == NULL) {
    printf("Student file (%s) is not present\n", studentFileName);
    return -1;
  }

  while(( str = fgets(line, MAX_LINE, f)) != NULL) {

    int len = strlen(line);
    if(len > 1 && line[len-1] == '\n') {
      line[len-1] = '\0';
      len = strlen(line);
      if(len > 0) {
        sscanf(line, "%d %s",&id, name);
        addStudent(name, id);
      }
    }
  }
  fclose(f);
  return 0;
}


void printStudentList(Student* listHead) {

  Student* stu;
  int i=0;
  for(stu = listHead; stu != NULL; stu = stu->next) {
    printf("\tStudent [%d]: %s (%d)\n", i, stu->name, stu->id);
    i++;
  }
}

void printDorms() {

  Dorm* dorm;
  for(dorm = dormListHead; dorm != NULL; dorm = dorm->next) {

    printf("Dorm [%d]: %s (%d)\n", dorm->dormNum, dorm->name, dorm->numStudents);
    printStudentList(dorm->studentList);
    printf("---------------------------------------------------------------------\n");
  }
}

void releaseStudentList(Student* studentList) {
  Student * stu = studentList;
  Student * tmp = stu;

  while(stu){
    free(stu->name);
    tmp = stu->next;
    free(stu);
    stu=tmp;
  }
}

void releaseMemory() {

  Dorm * dorm = dormListHead;
  Dorm * tmp = dorm;
  while(dorm) {

    releaseStudentList(dorm->studentList);
    free(dorm->name);
    tmp = dorm->next;
    free(dorm);
    dorm=tmp;
  }

}