// This program takes in two command line arguments, the first command
// line argument is one of either "word" or "number" and then the second 
// argument is the word or number to compare. The user is then asked for a 
// input based on whether they are comparing numbers or words. The two will then
// be compared. For words, we will count the number of letters that they 
// have in common. And for numbers we will either match them or not. 

// Sasha Vassar Week 5, Lecture 10

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

#define MAX_LENGTH 100

int char_match(char word1_char, char word2[MAX_LENGTH]);
int word_match(char word1[MAX_LENGTH], char word2[MAX_LENGTH]);

int main(int argc, char *argv[]){
    
    //Check if there are two arguments, if there are less - than you 
    //exit the program
    //./compare words happy
    if (argc != 3) {
        printf("You have not entered enough command line arguments. ");
        printf("Please enter a word or a number to compare! \n");
        return 1;
    } 
    // string '\0'
    // fgets NULL
    // getchar EOF
    
    // final element of argv will always be: argv[argc - 1]
    // If the first command line argument is a word, then compare the two words
    // for matches
    if(strcmp(argv[1], "words") == 0) {
        // Take in a string as input
        printf("Please type in a word to compare: ");
        char word_to_compare[MAX_LENGTH];
        fgets(word_to_compare, MAX_LENGTH, stdin);
        
        //char array[] = "hello"
        // {'h', 'e', 'l', 'l', 'o', '\0'}
        
        // check for a \n at the end of the input and remove it
        //'b''o''o''\0''\n'
        int last_letter = strlen(word_to_compare) - 1; //last letter = 4
        if (word_to_compare[last_letter] == '\n') { //word_to_compare[4] = '\n'?
            word_to_compare[last_letter] = '\0'; // word_to_compare[4] = '\n
        } 
        
        int match_counter = word_match(word_to_compare, argv[argc - 1]);
        printf("The number of letters that matched is %d.\n", match_counter); 
        
    // If the first command line argument is a number, then compare two numbers    
    } 
    /*else if () {
        int number = ;
        int comparison;
        printf("Please type in a number to compare: ");
        scanf("%d", &comparison);
        if (number == comparison) {
            printf("The numbers match\n");
        } else {
            printf("The numbers did not match\n");
        }
    
    }*/
    return 0;
}

// checks if character from first word is in second word, character
// by character, return the last index of character, or -1 if the character
// is not found 

int char_match(char word1_char, char word2[MAX_LENGTH]) {

    printf("Checking %c in word %s\n", word1_char, word2);
    int i = 0;
    int found_letter = -1; 
    while (word2[i] != '\0') {
        if (word2[i] == word1_char) {
            found_letter = i; 
        }
        i++;
    } 
    return found_letter;
}

// Checks for how many letters in word1 appear in word2
// Returns the number of letters that match

// Technology\0 Sucks
// T Sucks 
// e Sucks
// c Sucks
// (char word[], char word[])
int word_match(char word1[MAX_LENGTH], char word2[MAX_LENGTH]) {
    int matches = 0;
    int i = 0;
    while (word1[i] != '\0') {
        if ((char_match(word1[i], word2)) >= 0) {
            matches++;
        }   
        i++;
    }    
    return matches;
}