/*  fileIODemo1.c

    - uses prototypes
    - declares arrays
    - passes arrays to functions
    - loads array from a TEXT file
    - uses command line args to specify input file
    - uses fscanf

    - TO COMPILE:  gcc -o prog  fileIODemo1.c
    - TO EXECUTE:  ./prog text-file
*/

/******
** Exercise 1: What happens if the file is opened in "w" "w+" "r+" "a" "a+"
** modes? Caution: Backup the dictionary file before trying.
**
** Exercise 2: Can you write the loadDictionary program without passing the
** wordCount?
**
** Exercise 3: NOTE: TIME CONSUMING and addition to lab 2
**  Modify your lab2 calendar such that it inputs an additional event file.
**  Each line in this event file is of the format:
**    <year:int> <month:int> <date:int> <event:string>
**
**  The calendar will display the date, day and event in output file (say,
**  outEvent.txt)
**  Each line in the output will be of the format:
**    <date>/<month>/<year>: <day> : <event>
*****/

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

#define MAX_WORDS   100
#define MAX_WORD_LEN  30

void loadDictionary(char *fileName, char dictionary[][MAX_WORD_LEN], int *wordCount);
void printDictionary(char dictionary[][MAX_WORD_LEN], int wordCount);


int main(int argc, char *argv[])
{
    char dictionary[MAX_WORDS][MAX_WORD_LEN];
    int wordCount=0;

    loadDictionary(argv[1], dictionary, &wordCount); /* pass ADDR of wordCount to modify */

    printf("\n%d words read from %s\n", wordCount, argv[1]);

    printDictionary(dictionary, wordCount); /* pass wordCount's value here */

    return 0;
}


void loadDictionary(char *fileName, char dictionary[][MAX_WORD_LEN], int *wordCount)
{
    FILE *inFile;
    char wordBuffer[MAX_WORD_LEN]; /* fscanf into this buffer - then strcpy to table */

    if ((inFile = fopen(fileName, "r")) == NULL) {

      fprintf(stderr,"ERROR - Cannot open input file %s.  Program exiting!\n", fileName);
      exit(EXIT_FAILURE);
    }

    /* the loading loop will terminate if EOF is reached - OR - if the table fills up */

    while ((fscanf(inFile, "%s", wordBuffer) > 0) && (*wordCount < MAX_WORDS)) {

      strcpy(dictionary[*wordCount], wordBuffer);
      (*wordCount)++;
      printf("%3d: %s\n", *wordCount, wordBuffer); /* "%3d" right justifies output value 3 places */
    }

    fclose(inFile);
}


void printDictionary(char dictionary[][MAX_WORD_LEN], int wordCount)
{
    int i; /* declare vars at TOP of block, not interspersed with code */

    printf("\n");
    for (i = 0; i < wordCount; ++i)
      printf("%s ", dictionary[i]);
    printf("\n");
}