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

#define BUF_SIZE 256

typedef enum { Fileopen = 'o', Fileclose = 'c', Filesave = 's', Read = 'r',
Write = 'w', Copy = 'p', Search = 'f', Erase = 'e', NoL = 'n', Quit = 'q', Help = 'h'} Menu; // NoL = show the number of lines

void fileclose(FILE **fp, FILE **tp) {
  if (*fp != NULL) {
    if (*tp != NULL) {
      printf("current file was not saved");
    }
    fclose(*fp);
  }
}


void fileopen(FILE **fp, FILE **tp) {
  char fn[BUF_SIZE];
  int i = 0;

  if (*fp != NULL) {
    fileclose(fp, tp);
  }

  scanf("%s", fn);
  fflush(stdin);

  if (fn[0] != '\0') {
    if ((*fp = fopen(fn, "r+")) == NULL) {
      do {
        printf("No such file, create file?[y/n]");   i = getchar();  fflush(stdin);
        if (i == 'y') {
          *fp = fopen(fn, "w+");
        }
      } while (i != 'y' && i != 'n');
    }
    if (*fp != NULL) {
      *tp = fopen("temp.dat", "w+");
    }
    if (i == 0) {
      while ((i = fgetc(*fp)) != EOF)
        fputc(i, *tp);
      fclose(*fp);  fopen(fn, "r+");
      fclose(*tp);  fopen("temp.dat", "r+");
    }
  }
}


void search(FILE **tp) {
  char buffer[BUF_SIZE];
  char se[BUF_SIZE];
  int i;
  int l = 1;
  int len;

  scanf("%s", se);
  len = strlen(se);
  fflush(stdin);
  while ( (fgets(buffer, BUF_SIZE, *tp)) != NULL ) {
    for (i = 0; buffer[i] != '\n'; i++) {
      if (strncmp(se, buffer + i, len) == 0)
        printf("l%4d :%s", l, buffer);
    }
    l++;
  }
  fclose(*tp);
  *tp = fopen("temp.dat", "r+");
}

void quit(FILE **fp, FILE **tp) {
  if (*fp != NULL)
    fileclose(fp, tp);
  fclose(*tp);
  if (remove("temp.dat") == 1)
    puts("cannot delete temp.dat");
}
      


Menu selectmenu(void) {
  int ch;

  ch = getchar();
  fflush(stdin);
  return (Menu)ch;
}

int main(void)
{
  Menu menu;
  FILE *fp = NULL;
  FILE *tp = NULL;

  do {
    menu = selectmenu();
    switch (menu) {
      case Fileopen  : fileopen(&fp, &tp);   break;
      case Fileclose : fileclose(&fp, &tp);   break;
      case Filesave  :    break;
      case Read      :    break;
      case Write     :    break;
      case Copy      :    break;
      case Search    : search(&tp);   break;
      case Erase     :    break;
      case NoL       :    break;
      case Quit      : quit(&fp, &tp);   break;
      case Help      :    break;

      default        : printf("no such command\n");   break;
    }
  } while (menu != Quit);

  return 0;
}