const ATTRACTIONS = [
  "Family River Cruise",
  "Sky Carousel",
  "Falcon Coaster",
  "Desert Drop",
  "Oasis Rapids",
  "Wave Lagoon",
  "Qiddiya Dining Court",
  "Sunset Plaza Show"
];

const NODE_POSITIONS = {
  "HUB": { x: 150, y: 110 },
  "ZONE_FAMILY_N": { x: 70, y: 55 },
  "ZONE_FAMILY_S": { x: 70, y: 165 },
  "ZONE_THRILL": { x: 230, y: 65 },
  "ZONE_WATER": { x: 235, y: 165 },
  "ZONE_DINING": { x: 150, y: 195 }
};

const mustDoSelect = document.getElementById("must-do-select");
const mustDoChips = document.getElementById("must-do-chips");
const intensityRange = document.getElementById("intensity-range");
const walkingRange = document.getElementById("walking-range");
const intensityLabel = document.getElementById("intensity-label");
const walkingLabel = document.getElementById("walking-label");
const planBtn = document.getElementById("plan-btn");
const planSpinner = document.getElementById("plan-spinner");
const errorBanner = document.getElementById("error-banner");
const metricWait = document.getElementById("metric-wait");
const metricWalk = document.getElementById("metric-walk");
const metricEnjoy = document.getElementById("metric-enjoyment");
const barWait = document.getElementById("bar-wait");
const barWalk = document.getElementById("bar-walk");
const barEnjoy = document.getElementById("bar-enjoy");
const timeline = document.getElementById("timeline");

// Populate multi-select if not already in HTML (e.g. when JS runs first)
if (mustDoSelect && mustDoSelect.options.length <= 1) {
  ATTRACTIONS.forEach(function(name) {
    const opt = document.createElement("option");
    opt.value = name;
    opt.textContent = name;
    mustDoSelect.appendChild(opt);
  });
}

const selectedMustDo = new Set();

mustDoSelect.addEventListener("change", () => {
  const value = mustDoSelect.value;
  if (value && !selectedMustDo.has(value)) {
    selectedMustDo.add(value);
    renderChips();
  }
  mustDoSelect.value = "";
});

function renderChips() {
  mustDoChips.innerHTML = "";
  if (selectedMustDo.size === 0) {
    return;
  }
  Array.from(selectedMustDo).forEach(name => {
    const chip = document.createElement("div");
    chip.className = "chip";
    chip.textContent = name;
    const btn = document.createElement("button");
    btn.type = "button";
    btn.textContent = "×";
    btn.onclick = () => {
      selectedMustDo.delete(name);
      renderChips();
    };
    chip.appendChild(btn);
    mustDoChips.appendChild(chip);
  });
}

intensityRange.addEventListener("input", () => {
  intensityLabel.textContent = intensityRange.value;
});
walkingRange.addEventListener("input", () => {
  walkingLabel.textContent = walkingRange.value;
});

function setLoading(isLoading) {
  planBtn.disabled = isLoading;
  planSpinner.style.display = isLoading ? "inline-block" : "none";
}

function clearResults() {
  metricWait.textContent = "–";
  metricWalk.textContent = "–";
  metricEnjoy.textContent = "–";
  barWait.style.width = "0%";
  barWalk.style.width = "0%";
  barEnjoy.style.width = "0%";
  timeline.innerHTML = '<div class="empty-state">Your step‑by‑step plan will appear here after you click <strong>Plan My Day</strong>.</div>';
  const layer = document.getElementById("route-layer");
  if (layer) layer.innerHTML = "";
  const wrap = document.getElementById("system-response-wrap");
  if (wrap) wrap.style.display = "none";
}

function setError(message) {
  if (message) {
    errorBanner.textContent = message;
    errorBanner.style.display = "block";
  } else {
    errorBanner.style.display = "none";
  }
}

function renderMetrics(plan) {
  if (!plan) return;
  metricWait.textContent = plan.total_wait_minutes + " min";
  metricWalk.textContent = plan.total_walking_m + " m";
  metricEnjoy.textContent = plan.enjoyment_score.toFixed(1) + " / 10";

  const waitPct = Math.min(100, (plan.total_wait_minutes / 240) * 100);
  const walkPct = Math.min(100, (plan.total_walking_m / 6000) * 100);
  const enjoyPct = Math.min(100, (plan.enjoyment_score / 10) * 100);
  barWait.style.width = waitPct + "%";
  barWalk.style.width = walkPct + "%";
  barEnjoy.style.width = enjoyPct + "%";
}

function renderTimeline(stops) {
  timeline.innerHTML = "";
  if (!stops || stops.length === 0) {
    const empty = document.createElement("div");
    empty.className = "empty-state";
    empty.textContent = "No stops were generated for this window. Try expanding your time range or relaxing constraints.";
    timeline.appendChild(empty);
    return;
  }
  const hasSuggested = stops.some(function(s) { return s.is_suggested; });
  if (hasSuggested) {
    const note = document.createElement("div");
    note.className = "suggested-note";
    note.textContent = "Attractions marked \u201cSuggestion\u201d were added by the system to improve your day (e.g. to boost enjoyment). You only requested the others.";
    timeline.appendChild(note);
  }
  stops.forEach((stop, idx) => {
    const card = document.createElement("div");
    card.className = "stop-card";

    const step = document.createElement("div");
    step.className = "stop-step";
    const circle = document.createElement("div");
    circle.className = "stop-step-circle";
    circle.textContent = idx + 1;
    step.appendChild(circle);
    if (idx < stops.length - 1) {
      const line = document.createElement("div");
      line.className = "stop-step-line";
      step.appendChild(line);
    }

    const main = document.createElement("div");
    main.className = "stop-main";

    const title = document.createElement("div");
    title.className = "stop-title";
    title.appendChild(document.createTextNode(stop.attraction_name));
    if (stop.is_suggested) {
      const badge = document.createElement("span");
      badge.className = "suggested-badge";
      badge.textContent = "Suggestion";
      title.appendChild(badge);
    }
    main.appendChild(title);

    const time = document.createElement("div");
    time.className = "stop-time";
    time.textContent = stop.start_time + " – " + stop.end_time;
    main.appendChild(time);

    const meta = document.createElement("div");
    meta.className = "stop-meta";
    const waitPill = document.createElement("span");
    waitPill.className = "pill";
    waitPill.textContent = "Wait ~ " + stop.estimated_wait_minutes + " min";
    const walkPill = document.createElement("span");
    walkPill.className = "pill";
    walkPill.textContent = "Walk ~ " + stop.walking_distance_m + " m";
    meta.appendChild(waitPill);
    meta.appendChild(walkPill);
    main.appendChild(meta);

    card.appendChild(step);
    card.appendChild(main);
    timeline.appendChild(card);
  });
}

function renderRoute(stops) {
  const layer = document.getElementById("route-layer");
  if (!layer) return;
  layer.innerHTML = "";
  if (!stops || stops.length === 0) return;
  const points = [{ x: 150, y: 110 }];
  stops.forEach(s => {
    const n = NODE_POSITIONS[s.node_id];
    if (n) points.push(n);
  });
  if (points.length >= 2) {
    const d = points.map((p, i) => (i ? "L" : "M") + " " + p.x + " " + p.y).join(" ");
    const path = document.createElementNS("http://www.w3.org/2000/svg", "path");
    path.setAttribute("d", d);
    path.setAttribute("fill", "none");
    path.setAttribute("stroke", "#66a0ff");
    path.setAttribute("stroke-width", "3");
    path.setAttribute("stroke-linecap", "round");
    path.setAttribute("stroke-linejoin", "round");
    path.setAttribute("stroke-dasharray", "5 6");
    layer.appendChild(path);
  }
  stops.forEach((stop, idx) => {
    const n = NODE_POSITIONS[stop.node_id];
    if (!n) return;
    const g = document.createElementNS("http://www.w3.org/2000/svg", "g");
    const c = document.createElementNS("http://www.w3.org/2000/svg", "circle");
    c.setAttribute("cx", n.x);
    c.setAttribute("cy", n.y);
    c.setAttribute("r", "8");
    c.setAttribute("fill", "#ffb347");
    c.setAttribute("stroke", "#1b1630");
    c.setAttribute("stroke-width", "2");
    const t = document.createElementNS("http://www.w3.org/2000/svg", "text");
    t.setAttribute("x", n.x);
    t.setAttribute("y", n.y - 11);
    t.setAttribute("fill", "#fff5e6");
    t.setAttribute("font-size", "9");
    t.setAttribute("text-anchor", "middle");
    t.setAttribute("font-weight", "600");
    t.textContent = idx + 1;
    g.appendChild(c);
    g.appendChild(t);
    layer.appendChild(g);
  });
}

async function handlePlanClick() {
  setError("");
  clearResults();
  setLoading(true);
  try {
    const body = {
      visit_date: document.getElementById("visit-date").value.trim(),
      start_time: document.getElementById("start-time").value.trim(),
      end_time: document.getElementById("end-time").value.trim(),
      must_do_attractions: Array.from(selectedMustDo),
      intensity_preference: parseInt(intensityRange.value, 10),
      walking_tolerance: parseInt(walkingRange.value, 10),
    };
    const resp = await fetch("/api/v1/plan", {
      method: "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify(body),
    });
    if (!resp.ok) {
      const data = await resp.json().catch(() => ({}));
      throw new Error(data.detail || "Planning failed");
    }
    const data = await resp.json();
    const plan = data.plan || data;
    const system = data.system || null;
    renderMetrics(plan);
    renderTimeline(plan.stops || []);
    renderRoute(plan.stops || []);
    const wrap = document.getElementById("system-response-wrap");
    const bodyEl = document.getElementById("system-response-body");
    const jsonEl = document.getElementById("system-response-json");
    const toggle = document.getElementById("system-response-toggle");
    if (wrap && jsonEl) {
      wrap.style.display = "block";
      jsonEl.textContent = JSON.stringify(system || { plan: plan }, null, 2);
      if (bodyEl) bodyEl.classList.remove("open");
      if (toggle) {
        toggle.onclick = function() {
          if (bodyEl) bodyEl.classList.toggle("open");
          toggle.setAttribute("aria-expanded", bodyEl && bodyEl.classList.contains("open"));
        };
      }
    }
  } catch (err) {
    setError(err.message || "Something went wrong while planning your day.");
  } finally {
    setLoading(false);
  }
}

planBtn.addEventListener("click", handlePlanClick);