// ------------------------------
// MAP SETUP
// ------------------------------
var streets = L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
  attribution: '© OpenStreetMap contributors'
});

var satellite = L.tileLayer('https://server.arcgisonline.com/ArcGIS/rest/services/' +
  'World_Imagery/MapServer/tile/{z}/{y}/{x}', {
  attribution: 'Tiles © Esri'
});

var map = L.map('map', {
  center: [40.7608, -111.8910],
  zoom: 13,
  layers: [streets]
});

var baseMaps = { "Streets": streets, "Satellite": satellite };
L.control.layers(baseMaps).addTo(map);

const MJR_LINES = ["701", "703", "704", "720", "750"];
const LRT_LINES = ["701", "703", "704", "720"];
const FRONTRUNNER = ["750"];
const API_URL = "http://localhost:7653/api/v0/";

// ------------------------------
// ROUTE STYLES
// ------------------------------
const ROUTE_STYLES = {
  "701": { color: "#0074D9", train: "🔵", stop: "🔹" },
  "704": { color: "#2ECC40", train: "🟢", stop: "🟩" },
  "703": { color: "#FF4136", train: "🔴", stop: "🔺" },
  "750": { color: "#B10DC9", train: "🟣", stop: "🔮" },
  "720": { color: "#000000", train: "⚪", stop: "🔷" }
};

// ------------------------------
// ICON BUILDER
// ------------------------------
function buildIcon(emoji, bearing) {
  const rotate = bearing ? `transform: rotate(${bearing}deg); transform-origin: center;` : '';
  const svg = `
  <svg xmlns="http://www.w3.org/2000/svg" width="32" height="32">
    <text x="50%" y="50%" text-anchor="middle"
          dominant-baseline="central" font-size="26"
          font-family="Apple Color Emoji, Segoe UI Emoji, NotoColorEmoji, sans-serif"
          >
      ${emoji}
    </text>
  </svg>`;

  return L.divIcon({
    html: svg,
    className: "emoji-icon",
    iconSize: [32, 32],
    iconAnchor: [16, 16],
    popupAnchor: [0, -16]
  });
}

// ------------------------------
// MARKER HELPER
// ------------------------------
function addMarker(lat, lon, content, icon) {
  if (!isNaN(lat) && !isNaN(lon)) {
    const marker = L.marker([lat, lon], { icon });
    if (content) marker.bindPopup(content);
    return marker;
  }
  console.warn("Invalid coordinates:", lat, lon);
}

// ------------------------------
// ROUTE LINES
// ------------------------------
function drawPolyLine(polylinePoints, color) {
  L.polyline(polylinePoints, { color, weight: 4, opacity: 0.8 }).addTo(map);
}

function drawLine(route) {
  fetch(API_URL + "routepaths/" + route)
    .then(res => res.json())
    .then(data => {
      const points = data.data;
      if (!points || points.length === 0) return;
      const color = ROUTE_STYLES[route].color;

      let polylinePoints = [];
      let currentShape = points[0].shape_id;

      points.forEach(p => {
        if (p.shape_id === currentShape) {
          polylinePoints.push([p.lat, p.lng]);
        } else {
          drawPolyLine(polylinePoints, color);
          polylinePoints = [[p.lat, p.lng]];
          currentShape = p.shape_id;
        }
      });

      if (polylinePoints.length > 0) drawPolyLine(polylinePoints, color);
    })
    .catch(err => console.error("Error drawing line:", err));
}

function drawLines() {
  MJR_LINES.forEach(drawLine);
}

// ------------------------------
// STOPS
// ------------------------------
let stopMarkers = {};
function getStopsByRoute(route) {
  if (stopMarkers[route]) return;
  stopMarkers[route] = [];
  const stopIcon = buildIcon(ROUTE_STYLES[route].stop);

  fetch(API_URL + "stops/" + route)
    .then(res => res.json())
    .then(data => {
      data.data.forEach(s => {
        const lat = parseFloat(s.location.latitude);
        const lon = parseFloat(s.location.longitude);
        const marker = addMarker(
          lat, lon,
          `${s.stop_name}<br>${s.stop_desc}`,
          stopIcon
        ).addTo(map);
        stopMarkers[route].push(marker);
      });
    })
    .catch(err => console.error("Error fetching stops:", err));
}

// ------------------------------
// VEHICLES
// ------------------------------
let trainMarkers = {};
let filterType = "all";

const filterSelect = document.getElementById("filterSelect");
if (filterSelect) {
  filterSelect.addEventListener("change", (e) => {
    filterType = e.target.value;
  });
}

function refreshVehicles() {
  fetch(API_URL + "vehicles")
    .then(res => res.json())
    .then(data => {
      let vehicles = data.data;

      // Apply filter
      if (filterType === "lrt") {
        vehicles = vehicles.filter(v => LRT_LINES.includes(v.routeNum) || FRONTRUNNER.includes(v.routeNum));
      }

      vehicles = vehicles.filter(v => MJR_LINES.includes(v.routeNum));

      // Remove vehicles no longer active
      Object.keys(trainMarkers).forEach(id => {
        if (!vehicles.find(v => v.vehicleId == id)) {
          map.removeLayer(trainMarkers[id]);
          delete trainMarkers[id];
        }
      });

      vehicles.forEach(v => {
        const { vehicleId, routeNum, routeName, speed, bearing } = v;
        const lat = v.location.latitude;
        const lon = v.location.longitude;
        const icon = buildIcon(ROUTE_STYLES[routeNum].train, bearing);

        if (!trainMarkers[vehicleId]) {
          const marker = L.marker([lat, lon], { icon })
            .bindPopup(`${routeName}<br>Vehicle ${vehicleId}<br>Speed: ${(speed*2.23694).toFixed(1)} mph`)
            .addTo(map);
          marker.vehicleData = v;
          trainMarkers[vehicleId] = marker;
        } else {
          if (trainMarkers[vehicleId].slideTo) {
            trainMarkers[vehicleId].slideTo([lat, lon], { duration: 1000 });
          } else {
            trainMarkers[vehicleId].setLatLng([lat, lon]);
          }
          trainMarkers[vehicleId].setIcon(icon);
          trainMarkers[vehicleId].vehicleData = v;
        }
      });
    })
    .catch(err => console.error("Error refreshing vehicles:", err));
}

// ------------------------------
// USER LOCATION & TRAIN DETECTION
// ------------------------------
let userMarker, accuracyCircle;
const ON_BOARD_RADIUS = 50; // meters

if (navigator.geolocation) {
  navigator.geolocation.getCurrentPosition(
    (position) => {
      const lat = position.coords.latitude;
      const lon = position.coords.longitude;

      userMarker = L.circleMarker([lat, lon], {
        radius: 8,
        fillColor: "#007AFF",
        color: "#fff",
        weight: 2,
        opacity: 1,
        fillOpacity: 0.9
      }).addTo(map);
      userMarker.bindPopup("You are here").openPopup();

      accuracyCircle = L.circle([lat, lon], {
        radius: position.coords.accuracy,
        color: "#007AFF",
        fillColor: "#007AFF",
        fillOpacity: 0.2
      }).addTo(map);

      map.setView([lat, lon], 13);
    },
    (err) => console.warn("Geolocation error:", err.message),
    { enableHighAccuracy: true, timeout: 500, maximumAge: 0 }
  );

  navigator.geolocation.watchPosition(
    (position) => {
      const userLat = position.coords.latitude;
      const userLon = position.coords.longitude;

      if (userMarker) userMarker.setLatLng([userLat, userLon]);
      if (accuracyCircle) accuracyCircle.setLatLng([userLat, userLon]).setRadius(position.coords.accuracy);

      // Detect if user is on a train
      const vehicles = Object.values(trainMarkers).map(m => m.vehicleData);
      let closest = null, minDistance = Infinity;

      vehicles.forEach(v => {
        const distance = map.distance([userLat, userLon], [v.location.latitude, v.location.longitude]);
        if (distance < minDistance) {
          minDistance = distance;
          closest = v;
        }
      });

      if (closest && minDistance <= ON_BOARD_RADIUS) {
        console.log(`User is on vehicle ${closest.vehicleId} (${closest.routeNum})`);
      }
    },
    (err) => console.warn("Geolocation watch error:", err.message),
    { enableHighAccuracy: true, maximumAge: 0 }
  );
} else {
  console.warn("Geolocation not supported by this browser.");
}

// ------------------------------
// INITIAL LOAD
// ------------------------------
drawLines();
MJR_LINES.forEach(r => getStopsByRoute(r));
refreshVehicles();
setInterval(refreshVehicles, 1000);