content.js

'use strict';
/**
 * TelegramGuard Content Script (UTF-8)
 * Active ONLY on web.telegram.org. Tracks time and messages background.js.
 */

// Centralize state tracking to match background service worker precisely
let isBlocked = false;

// CSS Injection for full-screen blocking UI
const style = document.createElement('style');
style.textContent = `
  #tg-guard-blocker-overlay {
    position: fixed; top: 0; left: 0; width: 100vw; height: 100vh;
    background: radial-gradient(circle at center, #0a1428 0%, #050a14 100%);
    z-index: 2147483647; display: flex; align-items: center; justify-content: center;
    color: white; font-family: 'Segoe UI', Roboto, sans-serif; text-align: center;
  }
  .blocker-card {
    background: rgba(255, 255, 255, 0.03);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 24px; padding: 40px; max-width: 400px;
    box-shadow: 0 20px 50px rgba(0,0,0,0.5), 0 0 20px rgba(16, 185, 129, 0.15);
  }
  .btn-premium {
    background: linear-gradient(135deg, #10b981 0%, #047857 100%); color: white;
    border: 1px solid rgba(255, 255, 255, 0.1); padding: 12px 30px;
    border-radius: 14px; font-weight: 700; cursor: pointer; transition: 0.3s;
    font-size: 1rem; margin-top: 25px;
    text-shadow: 0 1px 2px rgba(0,0,0,0.3);
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.2);
  }
  .btn-premium:hover { transform: translateY(-2px); box-shadow: 0 0 25px rgba(16, 185, 129, 0.5); }
  .icon-lock { font-size: 4rem; margin-bottom: 20px; display: block; filter: drop-shadow(0 0 10px #fbbf24); }
  .modal-title { font-size: 2rem; color: #fbbf24; margin: 0 0 10px; font-weight: 800; }
  .modal-subtitle { opacity: 0.7; font-size: 0.95rem; margin: 0 0 15px; }
  .no-scroll { overflow: hidden !important; }
`;
document.head.appendChild(style);


// Main Blocking and Extension Enforcement Loop
async function enforceLimits() {
  const data = await chrome.storage.local.get(['usageToday', 'dailyLimit', 'isActive', 'extendUsed']);
  
  if (!data.isActive) {
    removeBlocker();
    return;
  }

  // Decimal math comparison (minutes decimal)
  const isDailyOver = (data.usageToday || 0) >= (data.dailyLimit || 30);
  
  if (isDailyOver) {
    showBlocker("Limit Reached", `Used your ${data.dailyLimit} min today.`, !data.extendUsed);
  } else {
    removeBlocker();
  }
}

function showBlocker(title, sub, allowExtend) {
  if (isBlocked) return;
  isBlocked = true;

  const overlay = document.createElement('div');
  overlay.id = 'tg-guard-blocker-overlay';
  overlay.innerHTML = `
    <div class="blocker-card">
      <span class="icon-lock">⌛</span> <h2 class="modal-title">${title}</h2>
      <p class="modal-subtitle">${sub}</p>
      ${allowExtend ? '<button class="btn-premium" id="extend-btn">Extend 5 Minutes</button>' : '<p style="color: #fbbf24; font-weight: 600;">Daily limit strictly enforced.</p>'}
    </div>
  `;
  document.body.appendChild(overlay);
  document.body.classList.add('no-scroll'); // Premium UX: stop scrolling the background page

  if (allowExtend) {
    document.getElementById('extend-btn').onclick = async () => {
        const d = await chrome.storage.local.get(['dailyLimit']);
        const newLimit = (d.dailyLimit || 30) + 5;
        await chrome.storage.local.set({ dailyLimit: newLimit, extendUsed: true });
        location.reload(); // Refresh the page to clear blockers immediately
    };
  }
}

function removeBlocker() {
    const existingOverlay = document.getElementById('tg-guard-blocker-overlay');
    if(existingOverlay) {
        existingOverlay.remove();
        document.body.classList.remove('no-scroll');
        isBlocked = false;
    }
}


// Real-Time Time Tracking Loop
// Important: Check visibility to ensure we only track active time.
if (location.href.includes('web.telegram.org')) {
  setInterval(async () => {
    if (document.visibilityState === 'visible') {
      // 1. Send centralized ticking message
      try {
        await chrome.runtime.sendMessage({ type: "TICK" });
      } catch(e) { /* ignore messaging errors when popup closes */ }
      
      // 2. Run blocking check loop
      enforceLimits();
    }
  }, 1000);
}