/* #define NDEBUG */
#include "Rabin_fingerprint.hpp"
#include "general_library.hpp"

#include <iostream>
#include <stdint.h>
#include <math.h>
#include <string>
#include <fstream>

void print_match (size_t index, size_t length, std::string &T) {
    std::cout << "Match found at index " << index << " with the text \"";
    for (size_t i = 0; i < length; i++)
        std::cout << T[index + i];
    std::cout << "\"" << std::endl;
}

int main() {
    /* std::ifstream ifs("../books/the_complete_works_of_william_shakespeare.txt"); */
    std::ifstream ifs("../books/genji_monogatari_english.txt");
    std::string T( (std::istreambuf_iterator<char>(ifs) ),
                    (std::istreambuf_iterator<char>() ) );

    /* std::string T = "Hello, this is my test string averylongword is a necessary word to exceed the 32 bit window."; */
    // Test without the modulo polynomial - and two matches
    std::string P = "word";
    // Test with the modulo polynomial
    /* std::string P = "averylongword"; */

    std::cout << "Searching for pattern:" << std::endl;
    std::cout << "    " << P << std::endl;
    /* std::cout << "in text:" << std::endl; */
    /* std::cout << "    " << T << std::endl; */
    std::cout << std::endl;

    /* uint32_t polynomial = pow(2, 30) + pow(2, 2) + 1; // x^31 + x^3 + 1 */
    uint32_t polynomial = get_random_irreducible_polynomial_in_Z2(31);
    /* uint32_t polynomial = 0b11010011100100000111101011110111; */
    // Test without the modulo polynomial
    size_t window_size_in_bits = P.length()*8;

    // Hash the pattern
    Rabin_fingerprint fP(polynomial, window_size_in_bits);
    for (char c : P)
        fP.push_char(c);

    // Hash the text
    Rabin_fingerprint fT(polynomial, window_size_in_bits);
    for (size_t i = 0; i < P.length(); i++)
        fT.push_char(T[i]);
    if (fT.get_fingerprint() == fP.get_fingerprint())
        print_match(0, P.length(), T);

    for (size_t i = P.length(); i < T.length(); i++) {
        fT.slide_char(T[i], T[i-P.length()]);
        if (fT.get_fingerprint() == fP.get_fingerprint())
            print_match(i-P.length()+1, P.length(), T);
    }

    std::cout << std::endl;
    std::cout << "Done!" << std::endl;

    return EXIT_SUCCESS;
}