/* ============================================================
   🔗 أزرار مشاركة لينكات الدروس + إغلاق الصفحة بعد واتساب
   ============================================================ */
(function() {

  // ===== 1) أزرار المشاركة جنب كل درس =====
  function addShareButtons() {
    const home = document.getElementById("homeScreen");
    if (!home || !home.classList.contains("active")) return;
    const list = document.getElementById("lessonsList");
    if (!list) return;
    if (list.querySelector(".share-link-btn")) return;

    list.querySelectorAll(".lesson-item").forEach(link => {
      if (link.querySelector(".share-link-btn")) return;
      const href = link.getAttribute("href") || "";
      const match = href.match(/stage=([^&]+)&lesson=([^&]+)/);
      if (!match) return;

      const fullURL = location.origin + location.pathname + "?stage=" + match[1] + "&lesson=" + match[2];

      const btn = document.createElement("button");
      btn.className = "share-link-btn";
      btn.innerHTML = "📤";
      btn.title = "انسخ لينك الدرس";
      btn.onclick = (e) => {
        e.preventDefault();
        e.stopPropagation();
        if (navigator.clipboard) {
          navigator.clipboard.writeText(fullURL).then(() => {
            btn.innerHTML = "✅";
            setTimeout(() => { btn.innerHTML = "📤"; }, 1500);
          });
        } else {
          const ta = document.createElement("textarea");
          ta.value = fullURL;
          document.body.appendChild(ta);
          ta.select();
          document.execCommand("copy");
          document.body.removeChild(ta);
          btn.innerHTML = "✅";
          setTimeout(() => { btn.innerHTML = "📤"; }, 1500);
        }
      };
      link.insertBefore(btn, link.firstChild);
    });
  }

  // راقب ظهور الصفحة الرئيسية
  new MutationObserver(() => {
    const home = document.getElementById("homeScreen");
    if (home && home.classList.contains("active")) {
      setTimeout(addShareButtons, 200);
    }
  }).observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ["class"] });

  document.addEventListener("DOMContentLoaded", () => setTimeout(addShareButtons, 500));

  // ===== 2) إغلاق الصفحة بعد إرسال الواتساب =====
  document.addEventListener("click", function(e) {
    const btn = e.target.closest("#whatsappBtn");
    if (!btn) return;
    setTimeout(() => {
      const result = document.getElementById("resultScreen");
      if (!result) return;
      result.innerHTML = `
        <div class="card" style="text-align:center;padding:50px 24px">
          <div style="font-size:72px;margin-bottom:16px">✅</div>
          <h1 style="color:#059669;margin-bottom:12px">تم إرسال نتيجتك</h1>
          <p style="color:#7c7a99;font-size:1.05rem;margin-bottom:8px">
            شكراً لك على إتمام الامتحان بنجاح 🌟
          </p>
          <p style="color:#7c7a99;font-size:1.05rem;margin-bottom:24px">
            لا يمكن إعادة الامتحان مرة أخرى.
          </p>
          <div style="background:#ecfdf5;border:2px solid #10b981;padding:14px;border-radius:12px;color:#065f46;font-weight:700;font-size:.95rem">
            📱 يمكنك إغلاق هذه الصفحة الآن
          </div>
        </div>
      `;
      window.history.pushState(null, "", window.location.href);
      window.onpopstate = function() {
        window.history.pushState(null, "", window.location.href);
      };
      setTimeout(() => { try { window.close(); } catch(e) {} }, 3000);
    }, 500);
  }, true);

  // ===== 3) كود Admin Panel =====
  const STORAGE_KEY = "admin_edits_v1";
  let adminState = { stage: null, unit: null, lesson: null, edits: {}, deleted: {}, added: {} };

  try {
    const saved = JSON.parse(localStorage.getItem(STORAGE_KEY) || "{}");
    adminState = { ...adminState, ...saved };
  } catch (e) {}

  function saveEdits() {
    try { localStorage.setItem(STORAGE_KEY, JSON.stringify(adminState)); } catch (e) {}
  }

  const $id = id => document.getElementById(id);

  function openAdmin() {
    document.querySelectorAll(".screen").forEach(s => s.classList.remove("active"));
    $id("adminScreen").classList.add("active");
    window.scrollTo({ top: 0 });
    initAdminFilters();
  }

  function closeAdmin() {
    document.querySelectorAll(".screen").forEach(s => s.classList.remove("active"));
    $id("homeScreen").classList.add("active");
    window.scrollTo({ top: 0 });
  }

  function initAdminFilters() {
    const stageSel = $id("adminStage");
    if (!stageSel || typeof CURRICULUM === "undefined") return;
    stageSel.innerHTML = "";
    Object.keys(CURRICULUM).forEach(key => {
      const opt = document.createElement("option");
      opt.value = key;
      opt.textContent = CURRICULUM[key].name;
      stageSel.appendChild(opt);
    });
    if (!adminState.stage || !CURRICULUM[adminState.stage]) adminState.stage = Object.keys(CURRICULUM)[0];
    stageSel.value = adminState.stage;
    stageSel.onchange = () => {
      adminState.stage = stageSel.value;
      adminState.unit = null; adminState.lesson = null;
      fillUnits();
    };
    fillUnits();
  }

  function fillUnits() {
    const unitSel = $id("adminUnit");
    if (!unitSel) return;
    const stage = CURRICULUM[adminState.stage];
    if (!stage) return;
    unitSel.innerHTML = "";
    stage.units.forEach((u, i) => {
      const opt = document.createElement("option");
      opt.value = i; opt.textContent = u.name;
      unitSel.appendChild(opt);
    });
    if (adminState.unit === null || adminState.unit >= stage.units.length) adminState.unit = 0;
    unitSel.value = adminState.unit;
    unitSel.onchange = () => {
      adminState.unit = parseInt(unitSel.value);
      adminState.lesson = null;
      fillLessons();
    };
    fillLessons();
  }

  function fillLessons() {
    const lessonSel = $id("adminLesson");
    if (!lessonSel) return;
    const stage = CURRICULUM[adminState.stage];
    const unit = stage.units[adminState.unit];
    if (!unit) return;
    lessonSel.innerHTML = "";
    unit.lessons.forEach((l, i) => {
      const opt = document.createElement("option");
      opt.value = i; opt.textContent = l.name;
      lessonSel.appendChild(opt);
    });
    if (adminState.lesson === null || adminState.lesson >= unit.lessons.length) adminState.lesson = 0;
    lessonSel.value = adminState.lesson;
    lessonSel.onchange = () => {
      adminState.lesson = parseInt(lessonSel.value);
      renderAdminQuestions();
    };
    renderAdminQuestions();
  }

  function getLessonQuestions() {
    const stage = CURRICULUM[adminState.stage];
    const unit = stage.units[adminState.unit];
    const lesson = unit.lessons[adminState.lesson];
    const key = adminState.stage + "_" + unit.id + "_" + lesson.id;
    let questions = lesson.questions.map((q, i) => ({
      ...q, originalIndex: i,
      isEdited: !!adminState.edits[key + "_" + i],
      isDeleted: !!adminState.deleted[key + "_" + i]
    }));
    const added = adminState.added[key] || [];
    added.forEach((q, i) => {
      questions.push({ ...q, originalIndex: "new_" + i, isEdited: false, isDeleted: false, isNew: true });
    });
    return { questions, key, lesson };
  }

  function renderAdminQuestions() {
    const list = $id("adminQuestionsList");
    if (!list) return;
    const { questions, key } = getLessonQuestions();
    $id("adminQCount").textContent = questions.filter(q => !q.isDeleted).length;
    let editCount = 0;
    Object.keys(adminState.edits).forEach(k => { if (k.startsWith(key + "_")) editCount++; });
    $id("adminEditCount").textContent = editCount;

    if (!questions.length) {
      list.innerHTML = '<div style="text-align:center;color:#7c7a99;padding:30px">لا توجد أسئلة. اضغط "إضافة سؤال".</div>';
      return;
    }

    list.innerHTML = "";
    const letters = ["A","B","C","D"];
    questions.forEach((q, displayIdx) => {
      const item = document.createElement("div");
      item.className = "admin-q-item";
      if (q.isEdited) item.classList.add("edited");
      if (q.isDeleted) item.classList.add("deleted");

      let optionsHtml = "";
      q.options.forEach((opt, oi) => {
        const cls = oi === q.correct ? "admin-q-opt correct" : "admin-q-opt";
        optionsHtml += '<div class="' + cls + '">' + letters[oi] + '. ' + opt + (oi === q.correct ? " ✓" : "") + '</div>';
      });

      let actions = "";
      if (q.isDeleted) {
        actions = '<button class="btn-edit" onclick="window.__adminRestore(\'' + q.originalIndex + '\')">♻️ استرجاع</button>';
      } else {
        actions = '<button class="btn-edit" onclick="window.__adminEdit(\'' + q.originalIndex + '\', ' + displayIdx + ')">✏️ تعديل</button>' +
                  '<button class="btn-del" onclick="window.__adminDelete(\'' + q.originalIndex + '\')">🗑️ حذف</button>';
      }

      const badge = q.isNew ? '<span style="color:#10b981;font-size:.75rem">جديد</span>' : '';
      const editedBadge = q.isEdited ? '<span style="color:#f59e0b;font-size:.75rem">مُعدّل</span>' : '';

      item.innerHTML = '<div class="admin-q-head"><span>السؤال ' + (displayIdx + 1) + ' ' + badge + ' ' + editedBadge + '</span></div>' +
        '<div class="admin-q-stem">' + q.text + '</div>' +
        '<div class="admin-q-options">' + optionsHtml + '</div>' +
        '<div class="admin-q-actions">' + actions + '</div>';
      list.appendChild(item);
    });
  }

  let currentEdit = null;

  function openEditModal(question, originalIndex) {
    currentEdit = { question, originalIndex };
    $id("editTitle").textContent = originalIndex === "new" ? "➕ إضافة سؤال جديد" : "✏️ تعديل السؤال";
    $id("editQuestionText").value = question ? question.text : "";
    for (let i = 0; i < 4; i++) {
      $id("editOpt" + i).value = question && question.options[i] ? question.options[i] : "";
    }
    const correct = question ? question.correct : 0;
    document.getElementById("opt" + correct + "radio").checked = true;
    $id("editDelete").style.display = originalIndex === "new" ? "none" : "block";
    $id("editModal").classList.remove("hidden");
    updatePreview();
  }

  function closeEditModal() {
    $id("editModal").classList.add("hidden");
    currentEdit = null;
  }

  function updatePreview() {
    const p = $id("editPreview");
    if (!p) return;
    p.innerHTML = $id("editQuestionText").value;
    if (window.MathJax && window.MathJax.typesetPromise) {
      window.MathJax.typesetPromise([p]).catch(()=>{});
    }
  }

  function saveEdit() {
    if (!currentEdit) return;
    const text = $id("editQuestionText").value.trim();
    if (!text) { alert("اكتب نص السؤال"); return; }
    const options = [];
    for (let i = 0; i < 4; i++) {
      const val = $id("editOpt" + i).value.trim();
      if (!val) { alert("املأ كل الاختيارات"); return; }
      options.push(val);
    }
    const correct = parseInt(document.querySelector('input[name="correctOpt"]:checked')?.value || 0);
    const newQ = { text, options, correct };
    const { key } = getLessonQuestions();

    if (currentEdit.originalIndex === "new") {
      if (!adminState.added[key]) adminState.added[key] = [];
      adminState.added[key].push(newQ);
    } else if (typeof currentEdit.originalIndex === "string" && currentEdit.originalIndex.startsWith("new_")) {
      const idx = parseInt(currentEdit.originalIndex.replace("new_", ""));
      if (adminState.added[key] && adminState.added[key][idx]) adminState.added[key][idx] = newQ;
    } else {
      adminState.edits[key + "_" + currentEdit.originalIndex] = newQ;
    }
    saveEdits();
    closeEditModal();
    renderAdminQuestions();
  }

  function deleteQuestion(originalIndex) {
    if (!confirm("حذف هذا السؤال؟")) return;
    const { key } = getLessonQuestions();
    adminState.deleted[key + "_" + originalIndex] = true;
    saveEdits();
    renderAdminQuestions();
  }

  function restoreQuestion(originalIndex) {
    const { key } = getLessonQuestions();
    delete adminState.deleted[key + "_" + originalIndex];
    saveEdits();
    renderAdminQuestions();
  }

  function exportAppJs() {
    const modified = JSON.parse(JSON.stringify(CURRICULUM));
    Object.keys(adminState.deleted).forEach(k => {
      const parts = k.split("_");
      const stage = parts[0], unitId = parts[1], lessonId = parts[2], idx = parseInt(parts[3]);
      if (isNaN(idx)) return;
      const s = modified[stage]; if (!s) return;
      s.units.forEach(u => {
        if (String(u.id) !== String(unitId)) return;
        u.lessons.forEach(l => {
          if (String(l.id) !== String(lessonId)) return;
          if (l.questions[idx]) l.questions[idx] = { __DEL: true };
        });
      });
    });
    Object.keys(adminState.edits).forEach(k => {
      const parts = k.split("_");
      const stage = parts[0], unitId = parts[1], lessonId = parts[2], idx = parseInt(parts[3]);
      if (isNaN(idx)) return;
      const e = adminState.edits[k];
      const s = modified[stage]; if (!s) return;
      s.units.forEach(u => {
        if (String(u.id) !== String(unitId)) return;
        u.lessons.forEach(l => {
          if (String(l.id) !== String(lessonId)) return;
          if (l.questions[idx]) l.questions[idx] = { text: e.text, options: e.options, correct: e.correct };
        });
      });
    });
    Object.keys(adminState.added).forEach(k => {
      const parts = k.split("_");
      const stage = parts[0], unitId = parts[1], lessonId = parts[2];
      const s = modified[stage]; if (!s) return;
      s.units.forEach(u => {
        if (String(u.id) !== String(unitId)) return;
        u.lessons.forEach(l => {
          if (String(l.id) !== String(lessonId)) return;
          adminState.added[k].forEach(q => {
            l.questions.push({ text: q.text, options: q.options, correct: q.correct });
          });
        });
      });
    });
    Object.keys(modified).forEach(stage => {
      modified[stage].units.forEach(u => {
        u.lessons.forEach(l => {
          l.questions = l.questions.filter(q => !q.__DEL);
        });
      });
    });

    let js = "/* app.js - نسخة معدلة " + new Date().toLocaleString("ar-EG") + " */\n\n";
    js += "const MY_WHATSAPP = \"" + (typeof MY_WHATSAPP !== "undefined" ? MY_WHATSAPP : "201110415311") + "\";\n";
    js += "const LESSON_DURATION = 15*60;\nconst UNIT_DURATION = 60*60;\nconst UNIT_EXAM_COUNT = 30;\n\n";
    js += "const Q = (text, options, correct) => ({ text, options, correct });\n\n";
    js += "const CURRICULUM = " + JSON.stringify(modified, null, 2) + ";\n";

    const blob = new Blob([js], { type: "text/javascript" });
    const url = URL.createObjectURL(blob);
    const a = document.createElement("a");
    a.href = url; a.download = "app.js";
    document.body.appendChild(a); a.click(); document.body.removeChild(a);
    URL.revokeObjectURL(url);
    alert("✅ تم تنزيل app.js الجديد");
  }

  const KEYS = [
    {t:"∠",l:"∠"},{t:"⊥",l:"⊥"},{t:"∥",l:"∥"},{t:"△",l:"△"},
    {t:"□",l:"□"},{t:"○",l:"○"},{t:"⊙",l:"⊙"},{t:"°",l:"°"},
    {t:"π",l:"π"},{t:"θ",l:"θ"},{t:"α",l:"α"},{t:"β",l:"β"},
    {t:"$x^2$",l:"x²"},{t:"$x^3$",l:"x³"},{t:"$\\frac{a}{b}$",l:"a/b"},{t:"$\\sqrt{x}$",l:"√x"},
    {t:"$\\sqrt[3]{x}$",l:"∛x"},{t:"$\\times$",l:"×"},{t:"$\\div$",l:"÷"},{t:"$\\pm$",l:"±"},
    {t:"$\\neq$",l:"≠"},{t:"$\\leq$",l:"≤"},{t:"$\\geq$",l:"≥"},{t:"$\\infty$",l:"∞"},
    {t:"$\\rightarrow$",l:"→"},{t:"$\\leftarrow$",l:"←"},{t:"$\\Rightarrow$",l:"⇒"},{t:"$\\pi$",l:"π"},
    {t:"$a^2+b^2=c^2$",l:"فيثاغورس"},{t:"$\\triangle$",l:"△"},{t:"$\\angle$",l:"∠"},{t:"$90°$",l:"90°"}
  ];

  function initKeyboard() {
    const kb = $id("mathKeyboard");
    if (!kb) return;
    kb.innerHTML = "";
    KEYS.forEach(k => {
      const btn = document.createElement("button");
      btn.type = "button";
      btn.textContent = k.l;
      btn.title = k.t;
      btn.onclick = () => insertAtCursor(k.t);
      kb.appendChild(btn);
    });
  }

  function insertAtCursor(text) {
    const target = document.activeElement;
    if (target && (target.tagName === "TEXTAREA" || target.tagName === "INPUT")) {
      const s = target.selectionStart || 0;
      const e = target.selectionEnd || 0;
      const v = target.value;
      target.value = v.slice(0, s) + text + v.slice(e);
      target.selectionStart = target.selectionEnd = s + text.length;
      target.focus();
    } else {
      const ta = $id("editQuestionText");
      if (ta) { ta.value += text; ta.focus(); }
    }
    updatePreview();
  }

  window.__adminEdit = function(orig, disp) {
    const { questions } = getLessonQuestions();
    openEditModal(questions[disp], orig);
  };
  window.__adminDelete = deleteQuestion;
  window.__adminRestore = restoreQuestion;

  document.addEventListener("DOMContentLoaded", () => {
    const openBtn = $id("openAdmin");
    const backBtn = $id("backFromAdmin");
    const addBtn = $id("addQuestionBtn");
    const saveBtn = $id("saveAllBtn");
    const exportBtn = $id("exportBtn");
    const resetBtn = $id("resetBtn");
    const editClose = $id("editClose");
    const editCancel = $id("editCancel");
    const editSave = $id("editSave");
    const editDelete = $id("editDelete");
    const editQText = $id("editQuestionText");
    const modal = $id("editModal");

    if (openBtn) openBtn.onclick = openAdmin;
    if (backBtn) backBtn.onclick = closeAdmin;
    if (addBtn) addBtn.onclick = () => openEditModal(null, "new");
    if (saveBtn) saveBtn.onclick = () => { saveEdits(); alert("✅ تم الحفظ في المتصفح"); };
    if (exportBtn) exportBtn.onclick = () => { if (confirm("تنزيل app.js الجديد؟")) exportAppJs(); };
    if (resetBtn) resetBtn.onclick = () => {
      if (!confirm("حذف كل التعديلات؟")) return;
      adminState.edits = {}; adminState.deleted = {}; adminState.added = {};
      saveEdits(); renderAdminQuestions();
    };
    if (editClose) editClose.onclick = closeEditModal;
    if (editCancel) editCancel.onclick = closeEditModal;
    if (editSave) editSave.onclick = saveEdit;
    if (editDelete) editDelete.onclick = () => {
      if (currentEdit && currentEdit.originalIndex !== "new") {
        deleteQuestion(currentEdit.originalIndex);
        closeEditModal();
      }
    };
    if (editQText) editQText.addEventListener("input", updatePreview);
    if (modal) modal.addEventListener("click", e => { if (e.target === modal) closeEditModal(); });

    initKeyboard();
  });

  console.log("✅ Admin Panel + Share + Close loaded");

})();