script.js

/* ==================================================
   CBC MASTER
   Main Application JavaScript
   ================================================== */


/* ==================================================
   CONFIGURATION
================================================== */

const HISTORY_KEY = "cbc_history";


/* ==================================================
   CUSTOM POPUP
================================================== */

/*
 * CBC MASTER custom notification popup.
 *
 * This replaces native alert() dialogs so the browser
 * does not display:
 *
 * "jose-ctr.github.io says"
 *
 * The popup elements are looked up when the function
 * is called, making this safe even if the HTML appears
 * before or after this script.
 */

function showPopup(message) {

  const popup =
    document.getElementById("myPopup");

  const popupText =
    document.getElementById("popupText");

  if (!popup || !popupText) {

    console.warn(
      "CBC MASTER popup elements were not found."
    );

    return;

  }

  popupText.textContent =
    String(message ?? "");

  popup.style.display = "flex";

  popup.setAttribute(
    "aria-hidden",
    "false"
  );

  document.body.classList.add(
    "popup-open"
  );

  const okButton =
    document.getElementById(
      "popupOkBtn"
    );

  if (okButton) {

    setTimeout(function () {

      okButton.focus();

    }, 50);

  }

}


function closePopup() {

  const popup =
    document.getElementById("myPopup");

  if (!popup) {

    return;

  }

  popup.style.display = "none";

  popup.setAttribute(
    "aria-hidden",
    "true"
  );

  document.body.classList.remove(
    "popup-open"
  );

}


const popupOkBtn =
  document.getElementById(
    "popupOkBtn"
  );


if (popupOkBtn) {

  popupOkBtn.addEventListener(
    "click",
    closePopup
  );

}


const popupOverlay =
  document.getElementById(
    "myPopup"
  );


if (popupOverlay) {

  popupOverlay.addEventListener(
    "click",
    function (event) {

      if (
        event.target === popupOverlay
      ) {

        closePopup();

      }

    }
  );

}


document.addEventListener(
  "keydown",
  function (event) {

    if (
      event.key === "Escape"
    ) {

      closePopup();

    }

  }
);


/* ==================================================
   DOM ELEMENTS
================================================== */

const menuBtn =
  document.getElementById("menuBtn");

const closeMenuBtn =
  document.getElementById("closeMenuBtn");

const sidebar =
  document.getElementById("sidebar");

const overlay =
  document.getElementById("overlay");

const startBtn =
  document.getElementById("startBtn");

const nextBtn =
  document.getElementById("nextBtn");

const studentInput =
  document.getElementById("student");

const gradeSelect =
  document.getElementById("grade");

const quizBox =
  document.getElementById("quizBox");

const quizQuestion =
  document.getElementById("quizQuestion");

const answerInput =
  document.getElementById("answerInput");

const resultBox =
  document.getElementById("result");

const historyBox =
  document.getElementById("historyBox");

const leaderboardBox =
  document.getElementById("leaderboardBox");

const notesPage =
  document.getElementById("notesPage");

const projectsPage =
  document.getElementById("projectsPage");

const clearHistoryBtn =
  document.getElementById("clearHistoryBtn");

const installBtn =
  document.getElementById("installBtn");


/* ==================================================
   QUESTION BANK
================================================== */

const questionBank = {

  MATH: [

    {
      q: "What is 5 + 7?",
      a: "12"
    },

    {
      q: "What is 9 × 3?",
      a: "27"
    },

    {
      q: "What is 48 ÷ 6?",
      a: "8"
    },

    {
      q: "What is 100 − 45?",
      a: "55"
    },

    {
      q: "What is 12 × 4?",
      a: "48"
    },

    {
      q: "What is 81 ÷ 9?",
      a: "9"
    },

    {
      q: "What is 25 + 36?",
      a: "61"
    },

    {
      q: "What is 90 − 27?",
      a: "63"
    },

    {
      q: "What is 7 × 8?",
      a: "56"
    },

    {
      q: "What is 144 ÷ 12?",
      a: "12"
    }

  ],


  ENGLISH: [

    {
      q: "What is the opposite of 'hot'?",
      a: "cold"
    },

    {
      q: "What is the plural of 'child'?",
      a: "children"
    },

    {
      q: "What is a noun?",
      a: "name"
    },

    {
      q: "What is the opposite of 'big'?",
      a: "small"
    },

    {
      q: "Complete: The sun ___ brightly.",
      a: "shines"
    },

    {
      q: "What is the past tense of 'go'?",
      a: "went"
    },

    {
      q: "What is the plural of 'book'?",
      a: "books"
    },

    {
      q: "What is the opposite of 'early'?",
      a: "late"
    },

    {
      q: "What is the past tense of 'eat'?",
      a: "ate"
    },

    {
      q: "What is the opposite of 'happy'?",
      a: "sad"
    }

  ],


  SCIENCE: [

    {
      q: "What planet do we live on?",
      a: "earth"
    },

    {
      q: "What gas do humans breathe in?",
      a: "oxygen"
    },

    {
      q: "What do plants need to make food?",
      a: "sunlight"
    },

    {
      q: "How many legs does a spider have?",
      a: "8"
    },

    {
      q: "What organ pumps blood around the body?",
      a: "heart"
    },

    {
      q: "What is H2O commonly called?",
      a: "water"
    },

    {
      q: "Which sense organ helps us see?",
      a: "eye"
    },

    {
      q: "What force pulls objects toward Earth?",
      a: "gravity"
    },

    {
      q: "What do humans use to breathe?",
      a: "lungs"
    },

    {
      q: "What is the natural satellite of Earth?",
      a: "moon"
    }

  ],


  SOCIAL: [

    {
      q: "What is the capital city of Kenya?",
      a: "nairobi"
    },

    {
      q: "What is the currency of Kenya?",
      a: "kenyan shilling"
    },

    {
      q: "How many counties are in Kenya?",
      a: "47"
    },

    {
      q: "What is the national language of Kenya?",
      a: "swahili"
    },

    {
      q: "What is the largest lake in Kenya?",
      a: "lake victoria"
    },

    {
      q: "What is the Kenyan national flag's main color at the top?",
      a: "black"
    },

    {
      q: "Which ocean borders Kenya?",
      a: "indian ocean"
    },

    {
      q: "What is Kenya's national animal?",
      a: "lion"
    },

    {
      q: "What is the name of Kenya's parliament?",
      a: "parliament"
    },

    {
      q: "What continent is Kenya in?",
      a: "africa"
    }

  ]

};


/* ==================================================
   QUIZ STATE
================================================== */

let currentQuestions = [];

let currentQuestionIndex = 0;

let currentScore = 0;

let currentStudent = "";

let currentGrade = "";

let answerLocked = false;


/* ==================================================
   PWA INSTALL STATE
================================================== */

let deferredInstallPrompt = null;


/* ==================================================
   UTILITY
================================================== */

function escapeHTML(value) {

  return String(value ?? "")
    .replace(/&/g, "&")
    .replace(/</g, "&lt;")
    .replace(/>/g, "&gt;")
    .replace(/"/g, "&quot;")
    .replace(/'/g, "&#039;");

}


function normalizeAnswer(value) {

  return String(value ?? "")
    .trim()
    .toLowerCase()
    .replace(/\s+/g, " ");

}


/* ==================================================
   SIDEBAR
================================================== */

function openSidebar() {

  if (sidebar) {

    sidebar.classList.add("open");

  }

  if (overlay) {

    overlay.classList.add("show");

  }

  document.body.classList.add(
    "menu-open"
  );

  if (menuBtn) {

    menuBtn.setAttribute(
      "aria-expanded",
      "true"
    );

  }

}


function closeSidebar() {

  if (sidebar) {

    sidebar.classList.remove("open");

  }

  if (overlay) {

    overlay.classList.remove("show");

  }

  document.body.classList.remove(
    "menu-open"
  );

  if (menuBtn) {

    menuBtn.setAttribute(
      "aria-expanded",
      "false"
    );

  }

}


if (menuBtn) {

  menuBtn.addEventListener(
    "click",
    openSidebar
  );

}


if (closeMenuBtn) {

  closeMenuBtn.addEventListener(
    "click",
    closeSidebar
  );

}


if (overlay) {

  overlay.addEventListener(
    "click",
    closeSidebar
  );

}


document.addEventListener(
  "keydown",
  function (event) {

    if (event.key === "Escape") {

      closeSidebar();

    }

  }
);


/* ==================================================
   PAGE NAVIGATION
================================================== */

function hideAllExtraPages() {

  if (notesPage) {

    notesPage.style.display = "none";

  }

  if (projectsPage) {

    projectsPage.style.display = "none";

  }

}


function showMainContent() {

  hideAllExtraPages();

  const mainContent =
    document.getElementById(
      "mainContent"
    );

  if (mainContent) {

    mainContent.style.display = "";

  }

}


function showNotes() {

  hideAllExtraPages();

  if (notesPage) {

    notesPage.style.display = "block";

    notesPage.scrollIntoView({
      behavior: "smooth",
      block: "start"
    });

  }

}


function showProjects() {

  hideAllExtraPages();

  if (projectsPage) {

    projectsPage.style.display = "block";

    projectsPage.scrollIntoView({
      behavior: "smooth",
      block: "start"
    });

  }

}


/* ==================================================
   NOTES
================================================== */

const notesBtn =
  document.getElementById(
    "notesBtn"
  );

const notesMainBtn =
  document.getElementById(
    "notesMainBtn"
  );


if (notesBtn) {

  notesBtn.addEventListener(
    "click",
    function () {

      closeSidebar();

      showNotes();

    }
  );

}


if (notesMainBtn) {

  notesMainBtn.addEventListener(
    "click",
    showNotes
  );

}


/* ==================================================
   PROJECTS
================================================== */

const projectsBtn =
  document.getElementById(
    "projectsBtn"
  );

const projectsMainBtn =
  document.getElementById(
    "projectsMainBtn"
  );


if (projectsBtn) {

  projectsBtn.addEventListener(
    "click",
    function () {

      closeSidebar();

      showProjects();

    }
  );

}


if (projectsMainBtn) {

  projectsMainBtn.addEventListener(
    "click",
    showProjects
  );

}


/* ==================================================
   HISTORY
================================================== */

function getHistory() {

  try {

    const stored =
      localStorage.getItem(
        HISTORY_KEY
      );

    if (!stored) {

      return [];

    }

    const parsed =
      JSON.parse(stored);

    return Array.isArray(parsed)
      ? parsed
      : [];

  } catch (error) {

    console.error(
      "Unable to read CBC history:",
      error
    );

    return [];

  }

}


function saveHistory(record) {

  const history =
    getHistory();

  history.unshift(record);

  const limitedHistory =
    history.slice(0, 50);

  try {

    localStorage.setItem(
      HISTORY_KEY,
      JSON.stringify(
        limitedHistory
      )
    );

  } catch (error) {

    console.error(
      "Unable to save CBC history:",
      error
    );

  }

}


function renderHistory() {

  if (!historyBox) {

    return;

  }

  const history =
    getHistory();

  if (history.length === 0) {

    historyBox.innerHTML = `
      <p>
        No quiz history yet.
      </p>
    `;

    return;

  }

  historyBox.innerHTML =
    history
      .map(function (item) {

        return `
          <div class="history-item">

            <strong>
              ${escapeHTML(
                item.student || "Student"
              )}
            </strong>

            <div>
              Grade:
              ${escapeHTML(
                item.grade || "-"
              )}
            </div>

            <div>
              Score:
              ${escapeHTML(
                item.score ?? 0
              )}/${escapeHTML(
                item.total ?? 0
              )}
            </div>

            <small>
              ${escapeHTML(
                item.date || ""
              )}
            </small>

          </div>
        `;

      })
      .join("");

}


/* ==================================================
   CLEAR HISTORY
================================================== */

function clearHistory() {

  const history =
    getHistory();

  if (history.length === 0) {

    showPopup(
      "There is no quiz history to clear."
    );

    return;

  }

  const confirmed =
    window.confirm(
      "Clear all CBC MASTER quiz history?\n\nThis cannot be undone."
    );

  if (!confirmed) {

    return;

  }

  try {

    localStorage.removeItem(
      HISTORY_KEY
    );

  } catch (error) {

    console.error(
      "Unable to clear CBC history:",
      error
    );

  }

  renderHistory();

  renderLeaderboard();

  showPopup(
    "Quiz history cleared."
  );

}


if (clearHistoryBtn) {

  clearHistoryBtn.addEventListener(
    "click",
    clearHistory
  );

}


/* ==================================================
   LEADERBOARD
================================================== */

function renderLeaderboard() {

  if (!leaderboardBox) {

    return;

  }

  const history =
    getHistory();

  if (history.length === 0) {

    leaderboardBox.innerHTML = `
      <p>
        No scores available yet.
      </p>
    `;

    return;

  }

  const sorted =
    [...history]
      .sort(function (a, b) {

        const scoreA =
          Number(a.score || 0);

        const scoreB =
          Number(b.score || 0);

        const totalA =
          Number(a.total || 0);

        const totalB =
          Number(b.total || 0);

        const percentageA =
          totalA > 0
            ? scoreA / totalA
            : 0;

        const percentageB =
          totalB > 0
            ? scoreB / totalB
            : 0;

        return (
          percentageB -
          percentageA
        );

      })
      .slice(0, 10);

  leaderboardBox.innerHTML =
    sorted
      .map(function (item, index) {

        return `
          <div class="leaderboard-item">

            <strong>
              ${index + 1}.
              ${escapeHTML(
                item.student ||
                "Student"
              )}
            </strong>

            <span>
              ${escapeHTML(
                item.score ?? 0
              )}/${escapeHTML(
                item.total ?? 0
              )}
            </span>

          </div>
        `;

      })
      .join("");

}


/* ==================================================
   HISTORY BUTTON
================================================== */

function showHistory() {

  closeSidebar();

  showMainContent();

  if (historyBox) {

    historyBox.scrollIntoView({
      behavior: "smooth",
      block: "start"
    });

  }

}


const historyBtn =
  document.getElementById(
    "historyBtn"
  );


if (historyBtn) {

  historyBtn.addEventListener(
    "click",
    showHistory
  );

}


/* ==================================================
   LEADERBOARD BUTTON
================================================== */

function showLeaderboard() {

  closeSidebar();

  showMainContent();

  if (leaderboardBox) {

    leaderboardBox.scrollIntoView({
      behavior: "smooth",
      block: "start"
    });

  }

}


const leaderboardBtn =
  document.getElementById(
    "leaderboardBtn"
  );


if (leaderboardBtn) {

  leaderboardBtn.addEventListener(
    "click",
    showLeaderboard
  );

}


/* ==================================================
   QUIZ QUESTION PREPARATION
================================================== */

function buildQuizQuestions() {

  const allQuestions = [];

  Object.keys(questionBank)
    .forEach(function (subject) {

      questionBank[subject]
        .forEach(function (question) {

          allQuestions.push({

            subject: subject,

            q: question.q,

            a: question.a

          });

        });

    });


  /* Fisher-Yates shuffle */

  for (
    let i = allQuestions.length - 1;
    i > 0;
    i--
  ) {

    const randomIndex =
      Math.floor(
        Math.random() * (i + 1)
      );

    [
      allQuestions[i],
      allQuestions[randomIndex]
    ] = [
      allQuestions[randomIndex],
      allQuestions[i]
    ];

  }


  return allQuestions.slice(
    0,
    Math.min(10, allQuestions.length)
  );

}


/* ==================================================
   QUIZ
================================================== */

function startQuiz() {

  currentStudent =
    studentInput
      ? studentInput.value.trim()
      : "";

  currentGrade =
    gradeSelect
      ? gradeSelect.value
      : "";


  if (!currentStudent) {

    showPopup(
      "Please enter the student's name."
    );

    if (studentInput) {

      studentInput.focus();

    }

    return;

  }


  if (!currentGrade) {

    showPopup(
      "Please select a grade."
    );

    if (gradeSelect) {

      gradeSelect.focus();

    }

    return;

  }


  currentQuestions =
    buildQuizQuestions();


  if (
    currentQuestions.length === 0
  ) {

    showPopup(
      "No quiz questions are available."
    );

    return;

  }


  currentQuestionIndex = 0;

  currentScore = 0;

  answerLocked = false;


  showMainContent();


  if (quizBox) {

    quizBox.style.display = "block";

  }


  if (resultBox) {

    resultBox.innerHTML = "";

  }


  if (answerInput) {

    answerInput.style.display = "";

    answerInput.disabled = false;

  }


  if (nextBtn) {

    nextBtn.style.display = "";

    nextBtn.disabled = false;

  }


  displayQuestion();


  if (quizBox) {

    quizBox.scrollIntoView({
      behavior: "smooth",
      block: "start"
    });

  }

}


/* ==================================================
   DISPLAY QUESTION
================================================== */

function displayQuestion() {

  if (
    !currentQuestions ||
    currentQuestions.length === 0
  ) {

    return;

  }


  const question =
    currentQuestions[
      currentQuestionIndex
    ];


  if (!question) {

    return;

  }


  answerLocked = false;


  if (quizQuestion) {

    quizQuestion.innerHTML = `
      <div>
        <strong>
          Question
          ${currentQuestionIndex + 1}
          of
          ${currentQuestions.length}
        </strong>
      </div>

      <div
        style="
          margin-top:10px;
        "
      >
        ${escapeHTML(question.q)}
      </div>
    `;

  }


  if (answerInput) {

    answerInput.value = "";

    answerInput.disabled = false;

    setTimeout(function () {

      answerInput.focus();

    }, 50);

  }


  if (nextBtn) {

    nextBtn.disabled = false;

    nextBtn.textContent =
      currentQuestionIndex ===
      currentQuestions.length - 1
        ? "Finish Quiz"
        : "Next Question";

  }

}


/* ==================================================
   CHECK ANSWER
================================================== */

function checkAnswer() {

  if (answerLocked) {

    return;

  }


  if (
    !currentQuestions ||
    currentQuestions.length === 0
  ) {

    return;

  }


  const question =
    currentQuestions[
      currentQuestionIndex
    ];


  if (!question) {

    return;

  }


  const userAnswer =
    normalizeAnswer(
      answerInput
        ? answerInput.value
        : ""
    );


  const correctAnswer =
    normalizeAnswer(
      question.a
    );


  if (!userAnswer) {

    showPopup(
      "Please enter an answer."
    );

    if (answerInput) {

      answerInput.focus();

    }

    return;

  }


  answerLocked = true;


  if (answerInput) {

    answerInput.disabled = true;

  }


  if (nextBtn) {

    nextBtn.disabled = true;

  }


  if (
    userAnswer ===
    correctAnswer
  ) {

    currentScore++;

    if (resultBox) {

      resultBox.innerHTML = `
        <div class="correct">
          ✓ Correct!
        </div>
      `;

    }

  } else {

    if (resultBox) {

      resultBox.innerHTML = `
        <div class="incorrect">
          ✗ Incorrect.
          Correct answer:
          <strong>
            ${escapeHTML(question.a)}
          </strong>
        </div>
      `;

    }

  }


  window.setTimeout(
    function () {

      if (
        currentQuestionIndex <
        currentQuestions.length - 1
      ) {

        currentQuestionIndex++;

        if (resultBox) {

          resultBox.innerHTML = "";

        }

        displayQuestion();

      } else {

        finishQuiz();

      }

    },
    600
  );

}


/* ==================================================
   NEXT BUTTON
================================================== */

if (nextBtn) {

  nextBtn.addEventListener(
    "click",
    checkAnswer
  );

}


/* ==================================================
   FINISH QUIZ
================================================== */

function finishQuiz() {

  const total =
    currentQuestions.length;


  const percentage =
    total > 0
      ? Math.round(
          (
            currentScore /
            total
          ) * 100
        )
      : 0;


  const record = {

    student:
      currentStudent,

    grade:
      currentGrade,

    score:
      currentScore,

    total:
      total,

    percentage:
      percentage,

    date:
      new Date().toLocaleString()

  };


  saveHistory(record);

  renderHistory();

  renderLeaderboard();


  if (quizQuestion) {

    quizQuestion.innerHTML = `
      <div class="quiz-complete">

        <h2>
          Quiz Complete
        </h2>

        <p>
          ${escapeHTML(currentStudent)}
        </p>

        <h3>
          Score:
          ${currentScore}/${total}
        </h3>

        <p>
          ${percentage}%
        </p>

      </div>
    `;

  }


  if (answerInput) {

    answerInput.style.display = "none";

    answerInput.disabled = true;

  }


  if (nextBtn) {

    nextBtn.style.display = "none";

  }


  if (resultBox) {

    resultBox.innerHTML = `
      <button
        type="button"
        class="action-btn"
        id="tryAgainBtn"
      >
        🔄 Try Another Quiz
      </button>
    `;


    const tryAgainBtn =
      document.getElementById(
        "tryAgainBtn"
      );


    if (tryAgainBtn) {

      tryAgainBtn.addEventListener(
        "click",
        startQuiz
      );

    }

  }

}


/* ==================================================
   START QUIZ BUTTON
================================================== */

if (startBtn) {

  startBtn.addEventListener(
    "click",
    startQuiz
  );

}


/* ==================================================
   RATE
================================================== */

function rateApp() {

  closeSidebar();

  showPopup(
    "Thank you for using CBC MASTER!"
  );

}


const rateBtn =
  document.getElementById(
    "rateBtn"
  );


if (rateBtn) {

  rateBtn.addEventListener(
    "click",
    rateApp
  );

}


/* ==================================================
   SHARE
================================================== */

function shareApp() {

  const shareData = {

    title:
      "CBC MASTER",

    text:
      "CBC MASTER — Teach smarter. Save time. Go digital.",

    url:
      window.location.href

  };


  if (
    navigator.share
  ) {

    navigator.share(
      shareData
    ).catch(function (error) {

      console.log(
        "Share cancelled:",
        error
      );

    });

  } else {

    showPopup(
      "Share this link:\n\n" +
      window.location.href
    );

  }

}


const shareBtn =
  document.getElementById(
    "shareBtn"
  );


if (shareBtn) {

  shareBtn.addEventListener(
    "click",
    shareApp
  );

}


/* ==================================================
   PWA INSTALL
================================================== */

window.addEventListener(
  "beforeinstallprompt",
  function (event) {

    /*
     * Prevent the browser from showing
     * its automatic mini-infobar.
     *
     * We will trigger installation from
     * the CBC MASTER install button.
     */

    event.preventDefault();

    deferredInstallPrompt =
      event;

    if (installBtn) {

      installBtn.disabled = false;

      installBtn.textContent =
        "📲 INSTALL CBC MASTER";

      installBtn.setAttribute(
        "aria-label",
        "Install CBC MASTER"
      );

    }

    console.log(
      "CBC MASTER PWA install prompt available."
    );

  }
);


/* ==================================================
   CHECK WHETHER APP IS INSTALLED
================================================== */

function isInstalledApp() {

  return (
    window.matchMedia(
      "(display-mode: standalone)"
    ).matches ||
    window.navigator.standalone === true
  );

}


/* ==================================================
   PWA INSTALL BUTTON
================================================== */

async function installCBCMaster() {

  closeSidebar();


  /* Already installed */

  if (isInstalledApp()) {

    if (installBtn) {

      installBtn.textContent =
        "✅ CBC MASTER INSTALLED";

      installBtn.disabled = true;

    }

    showPopup(
      "CBC MASTER is already installed on this device."
    );

    return;

  }


  /* Native browser installation prompt */

  if (deferredInstallPrompt) {

    try {

      deferredInstallPrompt.prompt();

      const choice =
        await deferredInstallPrompt.userChoice;

      console.log(
        "CBC MASTER install result:",
        choice.outcome
      );


      if (
        choice.outcome === "accepted"
      ) {

        if (installBtn) {

          installBtn.textContent =
            "✅ Installing CBC MASTER...";

          installBtn.disabled = true;

        }

      } else {

        if (installBtn) {

          installBtn.textContent =
            "📲 INSTALL CBC MASTER";

          installBtn.disabled = false;

        }

      }

    } catch (error) {

      console.error(
        "CBC MASTER installation prompt failed:",
        error
      );

    }


    /*
     * The browser installation prompt
     * can only be used once.
     */

    deferredInstallPrompt = null;

    return;

  }


  /*
   * The browser has not provided a native
   * installation prompt.
   *
   * Give the user the normal Android
   * browser installation instructions.
   */

  showPopup(
    "To install CBC MASTER:\n\n" +
    "1. Open your browser menu ⋮\n" +
    "2. Choose 'Install app' or 'Add to Home screen'\n" +
    "3. Confirm the installation."
  );

}


if (installBtn) {

  installBtn.addEventListener(
    "click",
    installCBCMaster
  );

}


/* ==================================================
   APP INSTALLED EVENT
================================================== */

window.addEventListener(
  "appinstalled",
  function () {

    console.log(
      "CBC MASTER was installed successfully."
    );

    deferredInstallPrompt = null;

    if (installBtn) {

      installBtn.textContent =
        "✅ CBC MASTER INSTALLED";

      installBtn.disabled = true;

    }

  }
);


/* ==================================================
   INITIAL INSTALL BUTTON STATE
================================================== */

if (installBtn) {

  if (isInstalledApp()) {

    installBtn.textContent =
      "✅ CBC MASTER INSTALLED";

    installBtn.disabled = true;

  } else {

    installBtn.textContent =
      "📲 INSTALL CBC MASTER";

    installBtn.disabled = false;

  }

}


/* ==================================================
   HISTORY / LEADERBOARD INITIALIZATION
================================================== */

renderHistory();

renderLeaderboard();


/* ==================================================
   LAST VISIT
================================================== */

try {

  localStorage.setItem(
    "cbc_last_visit",
    new Date().toISOString()
  );

} catch (error) {

  console.log(
    "Local storage unavailable:",
    error
  );

}


/* ==================================================
   SERVICE WORKER
================================================== */

if (
  "serviceWorker" in navigator
) {

  window.addEventListener(
    "load",
    function () {

      navigator.serviceWorker
        .register("./sw.js")
        .then(function (registration) {

          console.log(
            "CBC MASTER Service Worker registered:",
            registration.scope
          );

        })
        .catch(function (error) {

          console.error(
            "CBC MASTER Service Worker registration failed:",
            error
          );

        });

    }
  );

}


/* ==================================================
   FINAL STATUS
================================================== */

console.log(
  "CBC MASTER loaded successfully."
);