const fields = {
  text: document.getElementById("mobileText"),
  tape: document.getElementById("mobileTape"),
  margin: document.getElementById("mobileMargin"),
  font: document.getElementById("mobileFont"),
  copies: document.getElementById("mobileCopies"),
  align: document.getElementById("mobileAlign"),
  bold: document.getElementById("mobileBold"),
  frame: document.getElementById("mobileFrame"),
  preview: document.getElementById("mobilePreview"),
  message: document.getElementById("mobileMessage"),
};

function estimateTextLengthMm(text, fontSize, margin, frame) {
  const lines = String(text || " ").split("\n");
  const longest = lines.reduce((max, line) => Math.max(max, line.length), 0);
  const textWidth = Math.max(8, longest * fontSize * 0.62);
  return Math.min(300, Math.max(20, Math.ceil(textWidth + margin * 2 + (frame ? 4 : 0))));
}

function setMessage(text, type = "") {
  fields.message.textContent = text;
  fields.message.className = `message ${type}`;
}

function mobileDesign() {
  const tapeWidth = Number(fields.tape.value);
  const margin = Number(fields.margin.value);
  const text = fields.text.value.trim() || " ";
  const fontSize = Number(fields.font.value);
  const length = estimateTextLengthMm(text, fontSize, margin, fields.frame.checked);
  const objects = [];
  if (fields.frame.checked) {
    objects.push({
      id: "frame",
      type: "shape",
      x: margin,
      y: margin,
      w: Math.max(2, length - margin * 2),
      h: Math.max(2, tapeWidth - margin * 2),
      lineMm: 0.25,
      fill: false,
    });
  }
  objects.push({
    id: "text",
    type: "text",
    x: margin + (fields.frame.checked ? 1 : 0),
    y: margin,
    w: Math.max(2, length - margin * 2 - (fields.frame.checked ? 2 : 0)),
    h: Math.max(2, tapeWidth - margin * 2),
    text,
    fontSizeMm: fontSize,
    bold: fields.bold.checked,
    align: fields.align.value,
    valign: "middle",
  });
  return {
    tapeWidthMm: tapeWidth,
    lengthMm: length,
    autoLength: true,
    marginMm: margin,
    orientation: "landscape",
    cutMode: "auto",
    halfcut: "off",
    objects,
  };
}

async function send(url) {
  setMessage("Rendere Etikett...");
  const response = await fetch(url, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({ design: mobileDesign(), copies: Number(fields.copies.value) || 1 }),
  });
  const payload = await response.json();
  if (!payload.ok) {
    setMessage(payload.error || "Fehler", "error");
    return;
  }
  fields.preview.src = `${payload.image}?t=${Date.now()}`;
  setMessage(payload.message || "Vorschau erstellt.", "success");
}

document.getElementById("mobilePreviewBtn").addEventListener("click", () => send("/api/preview"));
document.getElementById("mobilePrintBtn").addEventListener("click", () => send("/api/print"));
document.getElementById("mobileDetect").addEventListener("click", async () => {
  setMessage("Erkenne Band...");
  const response = await fetch("/api/tape-info");
  const payload = await response.json();
  if (!payload.ok) {
    setMessage(payload.error || "Band konnte nicht erkannt werden.", "error");
    return;
  }
  fields.tape.value = String(payload.width);
  setMessage(`Band erkannt: ${payload.width} mm`, "success");
});

["text", "font", "margin", "frame", "bold", "align", "tape"].forEach((name) => {
  fields[name].addEventListener("input", () => {
    mobileDesign();
  });
});

mobileDesign();