/**
 * 
 * @param {Array<Answer>} answerData 
 * @returns 
 */
function answerQuestion(answerData){
    const question = document.querySelector(".question:not(.hidden)");
    if (!question) {
        return;
    }

    const questionTextDom = question.querySelector(".questionText .mattext");
    if (!questionTextDom) return;
    const questionText = questionTextDom.textContent.trim();

    const answersDom = question.querySelector("ul.coreContent");
    if (!answersDom) return;
    const answers = answersDom.children;

    for (let answer of  Array.from(answers)) {
        const input = answer.querySelector("input");
        if (!input) continue;
        input.checked = false;
    }

    const correctAnswers = findAnswers(answerData, questionText, answers);
    if (correctAnswers.length === 0) {
        return;
    }

    for (const answer of correctAnswers) {
        const input = answer.querySelector("input");
        if (!input) continue;
        input.checked = true;
    }
}

/**
 * 
 * @param {Array<Answer>} answerData 
 * @param {string} questionText 
 * @returns 
 */
function findAnswers(answerData, questionText, answers) {
    if (answerData === null) {
        return [];
    }

    const correctAnswers = [];
    for (let entry of answerData) {
        if (matchAnswer(questionText.trim(), entry.question.trim())) {
            for (let availableAnswer of answers) {
                for (let possibleAnswer of entry.answers) {
                    if (matchAnswer(availableAnswer.textContent.trim(), possibleAnswer)) {
                        correctAnswers.push(availableAnswer);
                    }
                }
            }
        }
    }

    return correctAnswers;
}

function matchAnswer(textA, textB) {
    const replaceRegex = /[^\w]/gi;
    textA = textA.replace(replaceRegex, "");
    textB = textB.replace(replaceRegex, "");
    return (textA === textB);
}

window.answerQuestion = answerQuestion;