"""
Ce module contient des fonctions utilisataires
"""
from HMM import HMM


def normalize_probabilities(prob_fr: float, prob_en: float, prob_it: float, searched: float) -> float:
    sum = prob_fr + prob_en + prob_it
    return searched / sum


def forward_detection(hmm_fr: HMM, hmm_en: HMM, hmm_it: HMM, O: str):
    """
    Prints the language detected with forward method
    :param hmm_fr: lambda_fr
    :param hmm_en: lambda_en
    :param hmm_it: lambda_it
    :param O: mot à détecter
    :return:
    """
    res_fr = hmm_fr.forward(O)
    res_en = hmm_en.forward(O)
    res_it = hmm_it.forward(O)

    proba_fr = normalize_probabilities(res_fr, res_en, res_it, res_fr)
    proba_en = normalize_probabilities(res_fr, res_en, res_it, res_en)
    proba_it = normalize_probabilities(res_fr, res_en, res_it, res_it)

    print(f'FR={proba_fr}, EN={proba_en}, IT={proba_it}')

    probas = [proba_fr, proba_en, proba_it]

    max_prob = proba_fr
    language_index = 0
    for index in 1..len(probas):
        if max_prob < probas[index]:
            max_prob = probas[index]
            language_index = index

    if language_index == 0:
        print('Français')
    elif language_index == 1:
        print('Anglais')
    else:
        print('Italien')


def backward_detection(hmm_fr: HMM, hmm_en: HMM, hmm_it: HMM, O: str):
    """
    Prints the language detected with backward method
    :param hmm_fr: lambda_fr
    :param hmm_en: lambda_en
    :param hmm_it: lambda_it
    :param O: mot à détecter
    :return:
    """
    res_fr = hmm_fr.backward(O)
    res_en = hmm_en.backward(O)
    res_it = hmm_it.backward(O)

    proba_fr = normalize_probabilities(res_fr, res_en, res_it, res_fr)
    proba_en = normalize_probabilities(res_fr, res_en, res_it, res_en)
    proba_it = normalize_probabilities(res_fr, res_en, res_it, res_it)

    print(f'FR={proba_fr}, EN={proba_en}, IT={proba_it}')

    probas = [proba_fr, proba_en, proba_it]

    max_prob = proba_fr
    language_index = 0
    for index in 1..len(probas):
        if max_prob < probas[index]:
            max_prob = probas[index]
            language_index = index

    if language_index == 0:
        print('Français')
    elif language_index == 1:
        print('Anglais')
    else:
        print('Italien')