(() => {
  const POLL_INTERVAL_MS = 750;
  let activeCancelUrl = null;

  function translate(key, fallback) {
    return window.__I18N_DATA?.[key] || fallback;
  }

  function format(template, values) {
    return Object.entries(values).reduce(
      (text, [key, value]) => text.replace(`{${key}}`, String(value)),
      template
    );
  }

  function stageLabel(stage) {
    const labels = {
      queued: ["search.progress_stage_queued", "En attente du serveur…"],
      preparing_graph: ["search.progress_stage_preparing", "Préparation du graphe…"],
      searching_descendants: ["search.progress_stage_descendants", "Recherche des descendants…"],
      searching_ancestors: ["search.progress_stage_ancestors", "Recherche des ascendants…"],
      building_result: ["search.progress_stage_result", "Construction du résultat…"],
      building_nodes: ["search.progress_stage_nodes", "Analyse des nœuds du résultat…"],
      building_relationships: ["search.progress_stage_relationships", "Chargement des relations…"],
      formatting_result: ["search.progress_stage_formatting", "Mise en forme du résultat…"],
      building_highlights: ["search.progress_stage_highlights", "Calcul des modèles importants…"],
      completed: ["search.progress_stage_completed", "Recherche terminée."],
      failed: ["search.progress_stage_failed", "La recherche a échoué."],
      cancelled: ["search.progress_stage_cancelled", "Recherche annulée."],
    };
    const [key, fallback] = labels[stage] || labels.queued;
    return translate(key, fallback);
  }

  function findProgressPanel(form) {
    return form.parentElement.querySelector(".search-progress");
  }

  function setSubmitting(form, submitting) {
    form.dataset.submitting = submitting ? "true" : "false";
    const submitButton = form.querySelector('button[type="submit"]');
    if (submitButton) submitButton.disabled = submitting;
  }

  function showError(form, progress, message) {
    const stage = progress.querySelector(".search-progress-stage");
    const status = progress.querySelector(".search-progress-status");
    const bar = progress.querySelector(".search-progress-bar");
    stage.textContent = translate(
      "search.progress_stage_failed",
      "La recherche a échoué."
    );
    status.textContent = message || translate(
      "search.progress_connection_error",
      "Impossible d’obtenir la progression depuis le serveur."
    );
    bar.style.width = "0%";
    progress.classList.remove("alert-info");
    progress.classList.add("alert-danger");
    setSubmitting(form, false);
  }

  function showCancelled(form, progress) {
    const stage = progress.querySelector(".search-progress-stage");
    const status = progress.querySelector(".search-progress-status");
    const note = progress.querySelector(".search-progress-note");
    const bar = progress.querySelector(".search-progress-bar");
    stage.textContent = stageLabel("cancelled");
    status.textContent = "";
    note.textContent = "";
    bar.style.width = "0%";
    progress.classList.remove("alert-info", "alert-danger");
    progress.classList.add("alert-secondary");
    setSubmitting(form, false);
  }

  function cancelActiveSearch() {
    if (!activeCancelUrl) return;
    const cancelUrl = activeCancelUrl;
    activeCancelUrl = null;
    if (
      navigator.sendBeacon
      && navigator.sendBeacon(
        cancelUrl,
        new Blob([], { type: "text/plain" })
      )
    ) {
      return;
    }
    fetch(cancelUrl, {
      method: "POST",
      credentials: "same-origin",
      keepalive: true,
    }).catch(() => {});
  }

  function renderStatus(progress, job) {
    const title = progress.querySelector(".search-progress-title");
    const stage = progress.querySelector(".search-progress-stage");
    const status = progress.querySelector(".search-progress-status");
    const note = progress.querySelector(".search-progress-note");
    const bar = progress.querySelector(".search-progress-bar");

    stage.textContent = stageLabel(job.stage);

    if (job.status === "queued" || job.stage === "queued") {
      title.textContent = translate(
        "search.progress_queue_title",
        "Recherche en file d’attente"
      );
      progress.classList.remove("alert-info", "alert-danger", "alert-secondary");
      progress.classList.add("alert-warning");

      const queueDetails = [];
      if (job.queue_position && job.queued_jobs) {
        queueDetails.push(
          format(
            translate(
              "search.progress_queue_position",
              "Position dans la file : {position}/{total}"
            ),
            {
              position: job.queue_position,
              total: job.queued_jobs,
            }
          )
        );
        const jobsAhead = job.queue_position - 1;
        if (jobsAhead === 0) {
          queueDetails.push(
            translate(
              "search.progress_queue_next",
              "Votre recherche est la prochaine."
            )
          );
        } else {
          queueDetails.push(
            format(
              translate(
                jobsAhead === 1
                  ? "search.progress_queue_ahead_one"
                  : "search.progress_queue_ahead_many",
                jobsAhead === 1
                  ? "1 recherche devant la vôtre"
                  : "{count} recherches devant la vôtre"
              ),
              { count: jobsAhead }
            )
          );
        }
      }
      if (job.running_jobs) {
        queueDetails.push(
          format(
            translate(
              job.running_jobs === 1
                ? "search.progress_queue_running_one"
                : "search.progress_queue_running_many",
              job.running_jobs === 1
                ? "1 recherche en cours"
                : "{count} recherches en cours"
            ),
            { count: job.running_jobs }
          )
        );
      }
      status.textContent = queueDetails.join(" · ");
      note.textContent = translate(
        "search.progress_queue_note",
        "La recherche démarrera automatiquement dès qu’une capacité sera disponible."
      );
      bar.style.width = "0%";
      bar.removeAttribute("aria-valuenow");
      return;
    }

    title.textContent = translate(
      "search.progress_title",
      "Recherche en cours…"
    );
    progress.classList.remove("alert-warning", "alert-danger", "alert-secondary");
    progress.classList.add("alert-info");

    const details = [
      format(
        translate("search.progress_elapsed", "Temps écoulé : {seconds} s"),
        { seconds: job.elapsed_seconds }
      ),
    ];

    if (job.completed_items !== null && job.total_items) {
      details.push(
        format(
          translate(
            "search.progress_items",
            "Éléments traités par le serveur : {completed}/{total}"
          ),
          {
            completed: job.completed_items,
            total: job.total_items,
          }
        )
      );
    }

    if (job.progress_percent !== null) {
      details.push(
        format(
          translate(
            "search.progress_server_percent",
            "Progression indiquée par le serveur : {percent} %"
          ),
          { percent: job.progress_percent }
        )
      );
      bar.style.width = `${job.progress_percent}%`;
      bar.setAttribute("aria-valuenow", String(job.progress_percent));
    } else {
      bar.style.width = "0%";
      bar.removeAttribute("aria-valuenow");
    }

    if (job.remaining_seconds !== null) {
      details.push(
        format(
          translate(
            "search.progress_remaining_step",
            "Temps restant estimé pour cette étape : {seconds} s"
          ),
          { seconds: job.remaining_seconds }
        )
      );
    }

    status.textContent = details.join(" · ");
    note.textContent = translate(
      "search.progress_server_note",
      "La progression repose sur les opérations réellement terminées par le serveur."
    );
  }

  async function readJson(response) {
    const body = await response.json().catch(() => ({}));
    if (!response.ok) {
      throw new Error(body.error || `${response.status} ${response.statusText}`);
    }
    return body;
  }

  async function pollJob(form, progress, statusUrl) {
    try {
      const job = await readJson(await fetch(statusUrl, {
        credentials: "same-origin",
        cache: "no-store",
      }));
      renderStatus(progress, job);

      if (job.status === "cancelled") {
        activeCancelUrl = null;
        showCancelled(form, progress);
        return;
      }
      if (job.result_url) {
        activeCancelUrl = null;
        window.location.assign(job.result_url);
        return;
      }
      window.setTimeout(() => pollJob(form, progress, statusUrl), POLL_INTERVAL_MS);
    } catch (error) {
      cancelActiveSearch();
      showError(form, progress, error.message);
    }
  }

  async function startSearch(form, progress) {
    const formData = new FormData(form);
    const endpoint = form.dataset.searchJobUrl || "/api/search-jobs";

    progress.classList.remove("d-none", "alert-danger");
    progress.classList.add("alert-info");
    progress.querySelector(".search-progress-title").textContent = translate(
      "search.progress_title",
      "Recherche en cours…"
    );
    renderStatus(progress, {
      stage: "queued",
      elapsed_seconds: 0,
      progress_percent: null,
      remaining_seconds: null,
      queue_position: null,
      queued_jobs: null,
      running_jobs: null,
      completed_items: null,
      total_items: null,
    });
    setSubmitting(form, true);

    try {
      const job = await readJson(await fetch(endpoint, {
        method: "POST",
        body: formData,
        credentials: "same-origin",
        headers: { Accept: "application/json" },
      }));
      activeCancelUrl = job.cancel_url;
      pollJob(form, progress, job.status_url);
    } catch (error) {
      showError(form, progress, error.message);
    }
  }

  document.addEventListener("DOMContentLoaded", () => {
    document.querySelectorAll("form[data-search-progress]").forEach((form) => {
      form.addEventListener("submit", (event) => {
        event.preventDefault();
        if (form.dataset.submitting === "true" || !form.reportValidity()) return;
        const progress = findProgressPanel(form);
        if (progress) startSearch(form, progress);
      });
    });
  });

  window.addEventListener("pagehide", cancelActiveSearch);
})();