(() => {
  "use strict";

  const modeEl = document.getElementById("qr-mode");
  const modeTextWrap = document.getElementById("mode-text");
  const modeWifiWrap = document.getElementById("mode-wifi");
  const textEl = document.getElementById("qr-text");
  const wifiSsidEl = document.getElementById("wifi-ssid");
  const wifiEncryptionEl = document.getElementById("wifi-encryption");
  const wifiPasswordEl = document.getElementById("wifi-password");
  const wifiPasswordField = document.getElementById("wifi-password-field");
  const wifiHiddenEl = document.getElementById("wifi-hidden");
  const cellSizeEl = document.getElementById("qr-cell-size");
  const correctionEl = document.getElementById("qr-correction");
  const fgColorEl = document.getElementById("qr-fg-color");
  const bgColorEl = document.getElementById("qr-bg-color");
  const logoInputEl = document.getElementById("qr-logo-input");
  const logoClearBtn = document.getElementById("qr-logo-clear");
  const generateBtn = document.getElementById("generate-btn");
  const downloadBtn = document.getElementById("download-btn");
  const canvas = document.getElementById("qr-canvas");
  const statusEl = document.getElementById("qr-status");
  const ctx = canvas.getContext("2d");

  let logoImage = null;

  function readLogoFile(file) {
    if (!file) return;
    const reader = new FileReader();
    reader.onload = () => {
      const img = new Image();
      img.onload = () => {
        logoImage = img;
        render();
      };
      img.src = reader.result;
    };
    reader.readAsDataURL(file);
  }

  logoInputEl.addEventListener("change", (e) => {
    readLogoFile(e.target.files[0]);
  });

  logoClearBtn.addEventListener("click", () => {
    logoImage = null;
    logoInputEl.value = "";
    render();
  });

  function escapeWifiField(value) {
    return String(value).replace(/([\\;,":])/g, "\\$1");
  }

  function buildWifiPayload() {
    const ssid = wifiSsidEl.value;
    const encryption = wifiEncryptionEl.value;
    const password = wifiPasswordEl.value;
    const hidden = wifiHiddenEl.checked;

    if (!ssid) return "";

    let payload = `WIFI:T:${encryption};S:${escapeWifiField(ssid)};`;
    if (encryption !== "nopass" && password) {
      payload += `P:${escapeWifiField(password)};`;
    }
    payload += `H:${hidden ? "true" : "false"};;`;
    return payload;
  }

  function updateModeVisibility() {
    const isWifi = modeEl.value === "wifi";
    modeTextWrap.style.display = isWifi ? "none" : "block";
    modeWifiWrap.style.display = isWifi ? "block" : "none";
    wifiPasswordField.style.display = wifiEncryptionEl.value === "nopass" ? "none" : "block";
  }

  modeEl.addEventListener("change", () => {
    updateModeVisibility();
    render();
  });

  wifiEncryptionEl.addEventListener("change", updateModeVisibility);

  [wifiSsidEl, wifiEncryptionEl, wifiPasswordEl, wifiHiddenEl].forEach((el) => {
    el.addEventListener("input", render);
    el.addEventListener("change", render);
  });

  function render() {
    const isWifi = modeEl.value === "wifi";
    const text = isWifi ? buildWifiPayload() : textEl.value;
    statusEl.classList.remove("error");

    if (!text) {
      ctx.clearRect(0, 0, canvas.width, canvas.height);
      canvas.width = 280;
      canvas.height = 280;
      statusEl.textContent = isWifi
        ? "Renseignez au moins le nom du réseau (SSID) pour générer le QR code."
        : "Saisissez un texte ou une URL pour générer le QR code.";
      return;
    }

    const cellSize = parseInt(cellSizeEl.value, 10) || 8;
    const requestedLevel = correctionEl.value;
    const level = logoImage ? "H" : requestedLevel;
    const fgColor = fgColorEl.value || "#000000";
    const bgColor = bgColorEl.value || "#ffffff";
    const margin = 4; // modules

    try {
      const qr = qrcode(0, level);
      qr.addData(text);
      qr.make();

      const moduleCount = qr.getModuleCount();
      const size = (moduleCount + margin * 2) * cellSize;
      canvas.width = size;
      canvas.height = size;

      ctx.imageSmoothingEnabled = false;
      ctx.fillStyle = bgColor;
      ctx.fillRect(0, 0, size, size);

      ctx.fillStyle = fgColor;
      for (let row = 0; row < moduleCount; row++) {
        for (let col = 0; col < moduleCount; col++) {
          if (qr.isDark(row, col)) {
            ctx.fillRect((col + margin) * cellSize, (row + margin) * cellSize, cellSize, cellSize);
          }
        }
      }

      if (logoImage) {
        const logoSize = size * 0.22;
        const pad = logoSize * 0.14;
        const x = (size - logoSize) / 2;
        const y = (size - logoSize) / 2;

        ctx.fillStyle = bgColor;
        ctx.fillRect(x - pad, y - pad, logoSize + pad * 2, logoSize + pad * 2);

        ctx.imageSmoothingEnabled = true;
        ctx.drawImage(logoImage, x, y, logoSize, logoSize);
      }

      statusEl.textContent = logoImage
        ? `QR code généré (correction ${level}, forcée par le logo).`
        : `QR code généré (correction ${level}).`;
    } catch (err) {
      statusEl.textContent = "Erreur : " + (err.message || "contenu trop long pour être encodé.");
      statusEl.classList.add("error");
    }
  }

  function downloadPng() {
    canvas.toBlob((blob) => {
      if (!blob) return;
      const url = URL.createObjectURL(blob);
      const a = document.createElement("a");
      a.href = url;
      a.download = "qrcode.png";
      document.body.appendChild(a);
      a.click();
      document.body.removeChild(a);
      URL.revokeObjectURL(url);
    }, "image/png");
  }

  [textEl, cellSizeEl, correctionEl, fgColorEl, bgColorEl].forEach((el) => {
    el.addEventListener("input", render);
  });

  generateBtn.addEventListener("click", render);
  downloadBtn.addEventListener("click", downloadPng);

  updateModeVisibility();
  render();
})();