/** Live-UI: Verbindungsbanner, Poller, gemeinsame Zustands-Labels. */

const RUN_STATES = {
  completed: "fertig",
  cancelled: "abgebrochen",
  error: "Fehler",
  in_progress: "druckt",
  printing: "druckt",
  paused: "pausiert",
  interrupted: "unterbrochen",
  standby: "bereit",
  heating: "heizt",
  complete: "fertig",
  offline: "offline",
  waiting: "wartet",
  running: "läuft",
};

let connBannerOk = true;
let connBannerTimer = 0;

function setConnectionBanner(ok, text) {
  let el = document.getElementById("conn-banner");
  if (!el) {
    el = document.createElement("div");
    el.id = "conn-banner";
    el.className = "conn-banner";
    el.setAttribute("role", "status");
    el.hidden = true;
    document.body.prepend(el);
  }
  clearTimeout(connBannerTimer);
  if (ok) {
    const wasBad = !connBannerOk;
    connBannerOk = true;
    if (wasBad && text) {
      el.textContent = text;
      el.className = "conn-banner ok";
      el.hidden = false;
      connBannerTimer = setTimeout(() => {
        el.hidden = true;
        el.textContent = "";
      }, 2800);
      return;
    }
    el.hidden = true;
    el.textContent = "";
    el.className = "conn-banner";
    return;
  }
  connBannerOk = false;
  el.textContent = text || "Keine Verbindung zum Server.";
  el.className = "conn-banner bad";
  el.hidden = false;
}

/**
 * @param {() => void | Promise<void>} fn
 * @param {number} intervalMs
 * @returns {{ start: () => void, stop: () => void }}
 */
function createPoller(fn, intervalMs) {
  const base = Math.max(1000, Number(intervalMs) || 5000);
  const maxMs = 60000;
  let timer = 0;
  let busy = false;
  let delay = base;
  let fails = 0;
  let running = false;

  function schedule() {
    if (!running) return;
    clearTimeout(timer);
    timer = setTimeout(tick, delay);
  }

  async function tick() {
    if (!running || document.hidden || busy) {
      schedule();
      return;
    }
    busy = true;
    try {
      await fn();
      delay = base;
      fails = 0;
      if (!connBannerOk) setConnectionBanner(true, "Wieder verbunden.");
      else setConnectionBanner(true, "");
    } catch (error) {
      fails += 1;
      delay = Math.min(maxMs, Math.max(base, delay * 2));
      if (fails >= 2) {
        setConnectionBanner(false, (error && error.message) || "Daten konnten nicht geladen werden.");
      }
    } finally {
      busy = false;
      schedule();
    }
  }

  function onVis() {
    if (!document.hidden && running) tick();
  }

  return {
    start() {
      if (running) return;
      running = true;
      document.addEventListener("visibilitychange", onVis);
      tick();
    },
    stop() {
      running = false;
      document.removeEventListener("visibilitychange", onVis);
      clearTimeout(timer);
      timer = 0;
    },
  };
}

const VERDICT_REASON_LABELS = {
  haftung: "Haftung",
  warping: "Warping",
  spaghetti: "Spaghetti",
  layer_shift: "Layer-Shift",
  verstopfung: "Verstopfung",
  farbe: "Farbe",
  sonstiges: "Sonstiges",
};

/**
 * Dialog vor „Platte geräumt“: Urteil, optional Grund und Stückzahlen.
 * @returns {Promise<object|null>} Payload für /abraeumen oder null bei Abbruch
 */
function promptAbraeumen(hostLabel) {
  return new Promise((resolve) => {
    const existing = document.getElementById("abraeumen-dlg");
    if (existing) existing.remove();
    const dlg = document.createElement("dialog");
    dlg.id = "abraeumen-dlg";
    dlg.className = "abraeumen-dlg";
    const reasons = Object.entries(VERDICT_REASON_LABELS)
      .map(([k, label]) => `<option value="${k}">${label}</option>`)
      .join("");
    dlg.innerHTML = `
      <form method="dialog" class="abraeumen-form">
        <h2>Platte geräumt</h2>
        <p class="tiny">${escapeHtml(hostLabel || "Drucker")}</p>
        <div class="field"><label for="ab-verdict">Urteil</label>
          <select id="ab-verdict" name="verdict">
            <option value="gut">gut</option>
            <option value="ausschuss">Ausschuss</option>
          </select>
        </div>
        <div class="field" id="ab-reason-wrap" hidden>
          <label for="ab-reason">Grund</label>
          <select id="ab-reason">${reasons}</select>
        </div>
        <div class="grid-2" id="ab-pieces" hidden>
          <div class="field"><label for="ab-ok">Stück gut</label><input id="ab-ok" type="number" min="0" step="1" value="0"></div>
          <div class="field"><label for="ab-bad">Stück schlecht</label><input id="ab-bad" type="number" min="0" step="1" value="1"></div>
        </div>
        <div class="actions">
          <button type="submit" value="ok" class="btn-primary">Quittieren</button>
          <button type="button" class="ghost" id="ab-cancel">Abbrechen</button>
        </div>
      </form>`;
    document.body.appendChild(dlg);
    const verdict = dlg.querySelector("#ab-verdict");
    const reasonWrap = dlg.querySelector("#ab-reason-wrap");
    const pieces = dlg.querySelector("#ab-pieces");
    function sync() {
      const scrap = verdict.value === "ausschuss";
      reasonWrap.hidden = !scrap;
      pieces.hidden = !scrap;
    }
    verdict.addEventListener("change", sync);
    sync();
    dlg.querySelector("#ab-cancel").addEventListener("click", () => {
      dlg.close();
      dlg.remove();
      resolve(null);
    });
    dlg.addEventListener("close", () => {
      if (dlg.returnValue !== "ok") {
        dlg.remove();
        resolve(null);
        return;
      }
      const payload = {
        confirm: true,
        verdict: verdict.value,
        verdict_reason: verdict.value === "ausschuss" ? dlg.querySelector("#ab-reason").value : "",
        pieces_ok: Number(dlg.querySelector("#ab-ok").value) || 0,
        pieces_bad: Number(dlg.querySelector("#ab-bad").value) || 0,
      };
      dlg.remove();
      resolve(payload);
    });
    dlg.showModal();
  });
}

window.RUN_STATES = RUN_STATES;
window.setConnectionBanner = setConnectionBanner;
window.createPoller = createPoller;
window.promptAbraeumen = promptAbraeumen;
window.VERDICT_REASON_LABELS = VERDICT_REASON_LABELS;