/**
 * landing.js — Pixel-Perfect inspired interactions for Nexus Autoparts
 *
 * Features:
 * - Animated canvas grid background (grid lines, stars at intersections, glowing tiles)
 * - Scroll-reveal via IntersectionObserver
 * - Counter animation on stat cards
 * - Typewriter effect
 * - Infinite brand marquee loader
 * - Theme toggle with icon swap
 */
(function () {
  'use strict';

  // ═══════════════════════════════════════════════════════════════════════════
  // THEME TOGGLE
  // ═══════════════════════════════════════════════════════════════════════════

  var themeIcon = document.getElementById('themeIcon');

  function updateThemeIcon() {
    var theme = document.documentElement.getAttribute('data-theme');
    if (themeIcon) themeIcon.innerHTML = theme === 'industrial' ? '☾' : '☀';
  }

  window.toggleTheme = function () {
    var html = document.documentElement;
    var current = html.getAttribute('data-theme');
    var next = current === 'industrial' ? 'modern' : 'industrial';
    html.setAttribute('data-theme', next);
    localStorage.setItem('nexus-theme', next);
    updateThemeIcon();
    // Canvas will pick up new CSS vars on next frame
  };

  updateThemeIcon();

  // ═══════════════════════════════════════════════════════════════════════════
  // CANVAS ANIMATED GRID
  // ═══════════════════════════════════════════════════════════════════════════

  var canvas = document.getElementById('heroCanvas');
  if (canvas) {
    var ctx = canvas.getContext('2d');
    var CELL = 80;
    var MAX_GLOWS = 6;
    var glows = [];
    var frame = 0;

    function resizeCanvas() {
      var hero = canvas.parentElement;
      canvas.width = hero.offsetWidth;
      canvas.height = hero.offsetHeight;
    }

    function getColor(varName) {
      return getComputedStyle(document.documentElement).getPropertyValue(varName).trim();
    }

    function drawStar(x, y, outer, inner, color) {
      ctx.beginPath();
      for (var i = 0; i < 4; i++) {
        var angle = (Math.PI / 2) * i;
        ctx.lineTo(x + Math.cos(angle) * outer, y + Math.sin(angle) * outer);
        ctx.lineTo(x + Math.cos(angle + Math.PI / 4) * inner, y + Math.sin(angle + Math.PI / 4) * inner);
      }
      ctx.closePath();
      ctx.fillStyle = color;
      ctx.fill();
    }

    function spawnGlow() {
      var cols = Math.floor(canvas.width / CELL);
      var rows = Math.floor(canvas.height / CELL);
      glows.push({
        col: Math.floor(Math.random() * cols),
        row: Math.floor(Math.random() * rows),
        life: 0,
        maxLife: 90 + Math.random() * 60, // 1.5-2.5s at 60fps
      });
    }

    function animateGrid() {
      frame++;
      ctx.clearRect(0, 0, canvas.width, canvas.height);

      var gridColor = getColor('--canvas-grid-color') || 'rgba(255,255,255,0.06)';
      var starColor = getColor('--canvas-star-color') || 'rgba(245,166,35,0.3)';
      var glowColor = getColor('--canvas-glow-color') || 'rgba(245,166,35,0.08)';

      var cols = Math.floor(canvas.width / CELL) + 1;
      var rows = Math.floor(canvas.height / CELL) + 1;

      // Draw grid lines
      ctx.strokeStyle = gridColor;
      ctx.lineWidth = 1;
      for (var c = 0; c <= cols; c++) {
        var x = c * CELL;
        ctx.beginPath();
        ctx.moveTo(x, 0);
        ctx.lineTo(x, canvas.height);
        ctx.stroke();
      }
      for (var r = 0; r <= rows; r++) {
        var y = r * CELL;
        ctx.beginPath();
        ctx.moveTo(0, y);
        ctx.lineTo(canvas.width, y);
        ctx.stroke();
      }

      // Draw stars at intersections (every other one for performance)
      for (c = 0; c <= cols; c += 2) {
        for (r = 0; r <= rows; r += 2) {
          drawStar(c * CELL, r * CELL, 6, 3, starColor);
        }
      }

      // Spawn glowing tiles
      if (glows.length < MAX_GLOWS && Math.random() < 0.03) {
        spawnGlow();
      }

      // Draw glowing tiles
      for (var i = glows.length - 1; i >= 0; i--) {
        var g = glows[i];
        g.life++;
        var progress = g.life / g.maxLife;
        var opacity = progress < 0.5 ? progress * 2 : (1 - progress) * 2;

        ctx.fillStyle = glowColor;
        ctx.globalAlpha = opacity;
        ctx.fillRect(g.col * CELL + 1, g.row * CELL + 1, CELL - 2, CELL - 2);

        // Subtle shadow glow
        ctx.shadowColor = glowColor;
        ctx.shadowBlur = 20;
        ctx.fillRect(g.col * CELL + 1, g.row * CELL + 1, CELL - 2, CELL - 2);
        ctx.shadowBlur = 0;

        ctx.globalAlpha = 1;

        if (g.life >= g.maxLife) glows.splice(i, 1);
      }

      requestAnimationFrame(animateGrid);
    }

    resizeCanvas();
    animateGrid();

    var resizeTimeout;
    window.addEventListener('resize', function () {
      clearTimeout(resizeTimeout);
      resizeTimeout = setTimeout(resizeCanvas, 150);
    });
  }

  // ═══════════════════════════════════════════════════════════════════════════
  // SCROLL REVEAL — IntersectionObserver
  // ═══════════════════════════════════════════════════════════════════════════

  var revealEls = document.querySelectorAll('.nx-reveal, .nx-reveal-scale');
  if ('IntersectionObserver' in window) {
    var observer = new IntersectionObserver(function (entries) {
      entries.forEach(function (entry) {
        if (entry.isIntersecting) {
          entry.target.classList.add('is-visible');
          observer.unobserve(entry.target);
        }
      });
    }, { threshold: 0.15, rootMargin: '0px 0px -40px 0px' });

    revealEls.forEach(function (el) {
      observer.observe(el);
    });
  } else {
    // Fallback: show all immediately
    revealEls.forEach(function (el) { el.classList.add('is-visible'); });
  }

  // ═══════════════════════════════════════════════════════════════════════════
  // COUNTER ANIMATION — Stat cards
  // ═══════════════════════════════════════════════════════════════════════════

  function animateCounter(el, target, format, suffix, duration) {
    var start = 0;
    var startTime = null;

    function step(timestamp) {
      if (!startTime) startTime = timestamp;
      var progress = Math.min((timestamp - startTime) / duration, 1);
      // Ease out cubic
      var eased = 1 - Math.pow(1 - progress, 3);
      var current = Math.floor(eased * target);

      if (format.indexOf('M') !== -1) {
        // e.g. "1.5M" or "15.8M"
        var decimals = target >= 10e6 ? 1 : 1;
        el.textContent = (current / 1e6).toFixed(decimals) + 'M' + suffix;
      } else if (format.indexOf('K') !== -1) {
        // e.g. "85K" or "304K"
        el.textContent = Math.floor(current / 1e3) + 'K' + suffix;
      } else {
        el.textContent = current + suffix;
      }

      if (progress < 1) requestAnimationFrame(step);
    }
    requestAnimationFrame(step);
  }

  // Trigger counters when stats become visible
  var statCards = document.querySelectorAll('.stat-card');
  if (statCards.length && 'IntersectionObserver' in window) {
    var statsObserver = new IntersectionObserver(function (entries) {
      entries.forEach(function (entry) {
        if (entry.isIntersecting) {
          var numEl = entry.target.querySelector('.number');
          if (numEl && !numEl._animated) {
            numEl._animated = true;
            var target = parseInt(numEl.getAttribute('data-target'), 10) || 0;
            var suffix = numEl.getAttribute('data-suffix') || '';
            var format = numEl.getAttribute('data-format') || 'num';
            animateCounter(numEl, target, format, suffix, 2000);
          }
          statsObserver.unobserve(entry.target);
        }
      });
    }, { threshold: 0.5 });

    statCards.forEach(function (card) { statsObserver.observe(card); });
  }

  // ═══════════════════════════════════════════════════════════════════════════
  // TYPEWRITER EFFECT
  // ═══════════════════════════════════════════════════════════════════════════

  var typewriterEl = document.getElementById('typewriterText');
  if (typewriterEl) {
    var phrases = [
      'POS + Inventario + CFDI 4.0 + Contabilidad',
      'Catalogo TecDoc: 1.5M+ partes, 304K aftermarket',
      '15.8M cross-references OEM ↔ aftermarket',
      'Chatbot IA con voz, foto y diagnostico',
      'WhatsApp Business integrado',
      'Busca por VIN, placas o numero de parte',
      'Marketplace B2B: bodegas ↔ talleres',
      'PWA + Android + modo kiosko + offline',
    ];
    var phraseIdx = 0;
    var charIdx = 0;
    var isDeleting = false;
    var typingSpeed = 50;

    function typeStep() {
      var current = phrases[phraseIdx];
      if (!isDeleting) {
        typewriterEl.textContent = current.substring(0, charIdx + 1);
        charIdx++;
        if (charIdx >= current.length) {
          isDeleting = true;
          setTimeout(typeStep, 2000); // Pause before deleting
          return;
        }
        setTimeout(typeStep, typingSpeed);
      } else {
        typewriterEl.textContent = current.substring(0, charIdx);
        charIdx--;
        if (charIdx < 0) {
          isDeleting = false;
          charIdx = 0;
          phraseIdx = (phraseIdx + 1) % phrases.length;
          setTimeout(typeStep, 400);
          return;
        }
        setTimeout(typeStep, 30);
      }
    }

    // Start after hero reveals
    setTimeout(typeStep, 1200);
  }

  // ═══════════════════════════════════════════════════════════════════════════
  // BRAND MARQUEE — Load from API + duplicate for seamless loop
  // ═══════════════════════════════════════════════════════════════════════════

  var marqueeContainer = document.getElementById('brandsMarquee');

  function buildMarquee(brands) {
    var html = '';
    brands.forEach(function (b) {
      html += '<a href="/catalog?brand=' + b.id_brand + '" class="brand-tag">' + escHtml(b.name_brand) + '</a>';
    });
    // Duplicate for seamless loop
    marqueeContainer.innerHTML = html + html;
  }

  function escHtml(s) {
    var d = document.createElement('div');
    d.textContent = s || '';
    return d.innerHTML;
  }

  // Fallback brands in case API fails
  var fallbackBrands = [
    'Toyota', 'Nissan', 'Ford', 'Volkswagen', 'Honda', 'Chevrolet',
    'Hyundai', 'Kia', 'Mazda', 'BMW', 'Mercedes-Benz', 'Audi',
    'Renault', 'Jeep', 'Dodge', 'Ram', 'Subaru', 'Mitsubishi',
    'Suzuki', 'Peugeot', 'Volvo', 'Fiat', 'Chrysler', 'Acura',
    'Infiniti', 'Lexus', 'Lincoln', 'Buick', 'GMC', 'Cadillac',
    'Porsche', 'Mini', 'Seat', 'Alfa Romeo', 'Land Rover', 'Jaguar'
  ];

  fetch('/api/catalog/brands')
    .then(function (r) { return r.json(); })
    .then(function (brands) {
      if (brands && brands.length > 0) {
        buildMarquee(brands);
      } else {
        buildMarquee(fallbackBrands.map(function (n, i) { return { id_brand: i, name_brand: n }; }));
      }
    })
    .catch(function () {
      buildMarquee(fallbackBrands.map(function (n, i) { return { id_brand: i, name_brand: n }; }));
    });

  // ── Live hero stats from API ──
  // The landing has 4 stat cards with data-format tags that identify them.
  // The counter animation runs on whatever data-target is set at observe
  // time, so we update all 4 targets BEFORE the IntersectionObserver fires.
  fetch('/api/catalog/stats')
    .then(function (r) { return r.json(); })
    .then(function (d) {
      // Maps data-format (the card's identifier) → the JSON key to pull.
      var statMap = [
        { format: '1.5M',  key: 'parts' },              // OEM parts
        { format: '304K',  key: 'aftermarket_parts' },  // Aftermarket
        { format: '15.8M', key: 'cross_references' },   // Cross-refs
        { format: 'num',   key: 'brands' },             // Brand count
      ];
      statMap.forEach(function (s) {
        var el = document.querySelector('[data-format="' + s.format + '"]');
        var value = d[s.key];
        if (el && typeof value === 'number' && value > 0) {
          el.setAttribute('data-target', value);
          // If the animation already ran (cached, instant DOM), snap to the
          // real value so users see the live number instead of the stale
          // hardcoded default.
          if (el._animated) {
            if (s.format.indexOf('M') !== -1) {
              el.textContent = (value / 1e6).toFixed(1) + 'M+';
            } else if (s.format.indexOf('K') !== -1) {
              el.textContent = Math.floor(value / 1e3) + 'K+';
            } else {
              el.textContent = String(value);
            }
          }
        }
      });
    })
    .catch(function () { /* fallback: hardcoded data-target values stay */ });

  // ═══════════════════════════════════════════════════════════════════════════
  // SMOOTH SCROLL for nav links
  // ═══════════════════════════════════════════════════════════════════════════

  document.querySelectorAll('.header-nav a[href^="#"]').forEach(function (a) {
    a.addEventListener('click', function (e) {
      e.preventDefault();
      var target = document.querySelector(a.getAttribute('href'));
      if (target) {
        target.scrollIntoView({ behavior: 'smooth', block: 'start' });
      }
    });
  });

  // ═══════════════════════════════════════════════════════════════════════════
  // HEADER — Solid on scroll
  // ═══════════════════════════════════════════════════════════════════════════

  var header = document.querySelector('.site-header');
  if (header) {
    window.addEventListener('scroll', function () {
      if (window.scrollY > 80) {
        header.style.background = 'var(--glass-bg-strong)';
      } else {
        header.style.background = 'var(--glass-bg)';
      }
    }, { passive: true });
  }

})();