/*
 * main.cpp
 *
 *  Created on: Oct 18, 2010
 *      Author: mike
 *      for use in Yale course CPSC 427a, Fall 2010
 */

/* Triangle word puzzle
 * Copyright 1995 by Michael J. Fischer

 * Solves challenge #85, "Pyramid", in "The IQ Challenge",
 * Philip J. Carter and Ken H. Russell, Barnes & Noble Books, 1993,
 * ISBN 1-56619-164-5

 * usage:  triangle [dictionary]
 *
 * Uses specified dictionary, or /usr/dict/words if no dictionay
 * specified.  Looks for words containing only the letters in
 * allowed_chars.  Tries to find a triangle of allowed words so that
 * each word is an anagram of the next shorter word plus one new
 * allowed letter.

 * Method: Reads in dictionary file.  Throws out disallowed words.
 * Builds a table of WordLists, where each WordList is a chain of
 * WordEntry objects for words of a given length.  Each WordEntry
 * contains a profile consisting of the letters of the word in sorted
 * order.  This enables two words to be quickly compared to see if one
 * is an anagram of a subword of the other.  A second pass over the
 * dictionary discards each word that is not an anagram of some next
 * shorter word plus a new letter.  It also sets a parent pointer in
 * each word to the shorter word from which it is derived.  A final
 * pass prints the triangle for each word of length triangle_max.
 */

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include "word.hpp"
#include "wordlist.hpp"
#include "dict.hpp"
#include "triangle.hpp"

/* constants */

#define DICTIONARY_FILE "/usr/share/dict/words"

static void usage(const char* prog) {
    cout << "usage: " << prog << " [dictionary [filter [min_size [max_size]]]]"
            << endl;
}

// --------------------------------------------------------------
int main(int argc, char *argv[]) {
    const char *prog;
    const char *dictname;
    int c;

    banner();

    /* check args */
    prog = argv[0];
    dictname = (argc <= 1) ? DICTIONARY_FILE : argv[1];
    Word::allowed_chars = (argc <= 2) ? "abcdefghijklmnopqrstuvwxyz" : argv[2];
    Word::triangle_min = (argc <= 3) ? MINLEN : strtol(argv[3], NULL, 0);
    Word::triangle_max = (argc <= 4) ? MAXLEN : strtol(argv[4], NULL, 0);
    if (argc > 5) {
        usage(prog);
        return 1;
    }
    if (Word::triangle_min > Word::triangle_max) {
        cout << "min_size " << Word::triangle_min
                << " should be at most max_size " << Word::triangle_max
                << endl;
        usage(prog);
        return 2;
    }
    if (Word::triangle_max > MAXLEN) {
        cout << "Can't handle triangles larger than " << MAXLEN << endl;
        usage(prog);
        return 2;
    }

    cout << "Finding size " << Word::triangle_max << " triangles\n";
    cout << " using dictionary " << dictname << "\n";
    cout << " with filter \"" << Word::allowed_chars << "\"\n" << endl;

    /* initialize character type table */
    for (c = 0; c < 256; c++)
        Word::allowed_set[c] = false;
    for (unsigned int k = 0; k < strlen(Word::allowed_chars); k++) {
        c = Word::allowed_chars[k];
        Word::allowed_set[c] = true;
    }

    /* read and store dictionary */
    Dictionary dict;
    dict.readDict(dictname);

    /* build triangle */
    cout << "Building triangle data structure" << endl;
    Triangle tri;
    tri.build(dict);

    /* print out triangles found */
    cout << "Some triangles" << endl;
    tri.print(cout);

    bye();
}