document.addEventListener("DOMContentLoaded", () => {
  const dataElement = document.getElementById("equipment-data");
  let equipmentByScenario = {};

  if (dataElement) {
    try {
      const parsed = JSON.parse(dataElement.textContent || "{}");
      if (parsed && typeof parsed === "object") {
        if (parsed.equipment && typeof parsed.equipment === "object") {
          equipmentByScenario = parsed.equipment;
        }
      }
    } catch (error) {
      console.error("Unable to parse equipment data", error);
    }
  }

  const filterSelect = document.getElementById("equipment-scenario-filter");
  const tableWrapper = document.getElementById("equipment-table-wrapper");
  const tableBody = document.getElementById("equipment-table-body");
  const emptyState = document.getElementById("equipment-empty");
  const form = document.getElementById("equipment-form");
  const feedbackEl = document.getElementById("equipment-feedback");

  const showFeedback = (message, type = "success") => {
    if (!feedbackEl) {
      return;
    }
    feedbackEl.textContent = message;
    feedbackEl.classList.remove("hidden", "success", "error");
    feedbackEl.classList.add(type);
  };

  const hideFeedback = () => {
    if (!feedbackEl) {
      return;
    }
    feedbackEl.classList.add("hidden");
    feedbackEl.textContent = "";
  };

  const renderEquipmentRows = (scenarioId) => {
    if (!tableBody || !tableWrapper || !emptyState) {
      return;
    }

    const key = String(scenarioId);
    const records = equipmentByScenario[key] || [];

    tableBody.innerHTML = "";

    if (!records.length) {
      emptyState.textContent = "No equipment recorded for this scenario yet.";
      emptyState.classList.remove("hidden");
      tableWrapper.classList.add("hidden");
      return;
    }

    emptyState.classList.add("hidden");
    tableWrapper.classList.remove("hidden");

    records.forEach((record) => {
      const row = document.createElement("tr");
      row.innerHTML = `
        <td>${record.name || "—"}</td>
        <td>${record.description || "—"}</td>
      `;
      tableBody.appendChild(row);
    });
  };

  if (filterSelect) {
    filterSelect.addEventListener("change", (event) => {
      const value = event.target.value;
      if (!value) {
        if (emptyState && tableWrapper && tableBody) {
          emptyState.textContent =
            "Choose a scenario to review the equipment list.";
          emptyState.classList.remove("hidden");
          tableWrapper.classList.add("hidden");
          tableBody.innerHTML = "";
        }
        return;
      }
      renderEquipmentRows(value);
    });
  }

  const submitEquipment = async (event) => {
    event.preventDefault();
    hideFeedback();

    if (!form) {
      return;
    }

    const formData = new FormData(form);
    const scenarioId = formData.get("scenario_id");
    const payload = {
      scenario_id: scenarioId ? Number(scenarioId) : null,
      name: formData.get("name"),
      description: formData.get("description") || null,
    };

    try {
      const response = await fetch("/api/equipment/", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify(payload),
      });

      if (!response.ok) {
        const errorDetail = await response.json().catch(() => ({}));
        throw new Error(
          errorDetail.detail || "Unable to add equipment record."
        );
      }

      const result = await response.json();
      const mapKey = String(result.scenario_id);

      if (!Array.isArray(equipmentByScenario[mapKey])) {
        equipmentByScenario[mapKey] = [];
      }
      equipmentByScenario[mapKey].push(result);

      form.reset();
      showFeedback("Equipment saved.", "success");

      if (filterSelect && filterSelect.value === String(result.scenario_id)) {
        renderEquipmentRows(filterSelect.value);
      }
    } catch (error) {
      showFeedback(error.message || "An unexpected error occurred.", "error");
    }
  };

  if (form) {
    form.addEventListener("submit", submitEquipment);
  }

  if (filterSelect && filterSelect.value) {
    renderEquipmentRows(filterSelect.value);
  }
});