import * as THREE from "three";

import { BGP_CONFIG, CONFIG, PATHS } from "./constants.js";
import { latLonToVector3 } from "./utils.js";

const bgpGroup = new THREE.Group();
const bgpOverlayGroup = new THREE.Group();
const collectorMarkers = [];
const anomalyMarkers = [];
const anomalyCountByCollector = new Map();

let showBGP = true;
let totalAnomalyCount = 0;
let textureCache = null;
let activeEventOverlay = null;
const relativeTimeFormatter = new Intl.RelativeTimeFormat("zh-CN", {
  numeric: "auto",
});

function getMarkerTexture() {
  if (textureCache) return textureCache;

  const canvas = document.createElement("canvas");
  canvas.width = 128;
  canvas.height = 128;

  const context = canvas.getContext("2d");
  if (!context) {
    textureCache = new THREE.Texture(canvas);
    return textureCache;
  }

  const gradient = context.createRadialGradient(64, 64, 8, 64, 64, 56);
  gradient.addColorStop(0, "rgba(255,255,255,1)");
  gradient.addColorStop(0.24, "rgba(255,255,255,0.92)");
  gradient.addColorStop(0.58, "rgba(255,255,255,0.35)");
  gradient.addColorStop(1, "rgba(255,255,255,0)");

  context.fillStyle = gradient;
  context.beginPath();
  context.arc(64, 64, 56, 0, Math.PI * 2);
  context.fill();

  textureCache = new THREE.CanvasTexture(canvas);
  return textureCache;
}

function normalizeSeverity(severity) {
  const value = String(severity || "").trim().toLowerCase();

  if (value === "critical") return "critical";
  if (value === "high" || value === "major") return "high";
  if (value === "medium" || value === "moderate" || value === "warning") {
    return "medium";
  }
  if (value === "low" || value === "info" || value === "informational") {
    return "low";
  }

  return "medium";
}

function getSeverityColor(severity) {
  return BGP_CONFIG.severityColors[normalizeSeverity(severity)];
}

function getSeverityScale(severity) {
  return BGP_CONFIG.severityScales[normalizeSeverity(severity)];
}

function formatLocalDateTime(value) {
  if (!value) return "-";

  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return String(value);

  return `${date.getFullYear()}/${String(date.getMonth() + 1).padStart(2, "0")}/${String(date.getDate()).padStart(2, "0")} ${String(date.getHours()).padStart(2, "0")}:${String(date.getMinutes()).padStart(2, "0")}:${String(date.getSeconds()).padStart(2, "0")}`;
}

function toDate(value) {
  if (!value) return null;
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return null;
  return date;
}

function formatRelativeTime(value) {
  const date = toDate(value);
  if (!date) return null;

  const diffMs = date.getTime() - Date.now();
  const absMs = Math.abs(diffMs);

  if (absMs < 60 * 1000) {
    return relativeTimeFormatter.format(Math.round(diffMs / 1000), "second");
  }
  if (absMs < 60 * 60 * 1000) {
    return relativeTimeFormatter.format(Math.round(diffMs / (60 * 1000)), "minute");
  }
  if (absMs < 24 * 60 * 60 * 1000) {
    return relativeTimeFormatter.format(Math.round(diffMs / (60 * 60 * 1000)), "hour");
  }
  return relativeTimeFormatter.format(
    Math.round(diffMs / (24 * 60 * 60 * 1000)),
    "day",
  );
}

export function formatBGPSeverityLabel(severity) {
  const normalized = normalizeSeverity(severity);
  switch (normalized) {
    case "critical":
      return "严重";
    case "high":
      return "高";
    case "medium":
      return "中";
    case "low":
      return "低";
    default:
      return "中";
  }
}

export function formatBGPAnomalyTypeLabel(type) {
  const value = String(type || "").trim().toLowerCase();
  if (!value) return "-";

  if (value.includes("hijack")) return "前缀劫持";
  if (value.includes("leak")) return "路由泄露";
  if (value.includes("withdraw")) return "大规模撤销";
  if (value.includes("subprefix") || value.includes("more_specific")) {
    return "更具体前缀异常";
  }
  if (value.includes("path")) return "路径突变";
  if (value.includes("flap")) return "路由抖动";

  return String(type);
}

export function formatBGPStatusLabel(status) {
  const value = String(status || "").trim().toLowerCase();
  if (!value) return "-";
  if (value === "active") return "活跃";
  if (value === "resolved") return "已恢复";
  if (value === "suppressed") return "已抑制";
  return String(status);
}

export function formatBGPCollectorStatus(status) {
  const value = String(status || "").trim().toLowerCase();
  if (!value) return "在线";
  if (value === "online") return "在线";
  if (value === "offline") return "离线";
  return String(status);
}

export function formatBGPConfidence(value) {
  if (value === null || value === undefined || value === "") return "-";
  const number = Number(value);
  if (!Number.isFinite(number)) return String(value);
  if (number >= 0 && number <= 1) {
    return `${Math.round(number * 100)}%`;
  }
  return `${Math.round(number)}%`;
}

export function formatBGPLocation(city, country) {
  const cityText = city || "";
  const countryText = country || "";
  if (cityText && countryText) return `${cityText}, ${countryText}`;
  return cityText || countryText || "-";
}

export function formatBGPRouteChange(originAsn, newOriginAsn) {
  const from = originAsn ?? "-";
  const to = newOriginAsn ?? "-";

  if ((from === "-" || from === "" || from === null) && (to === "-" || to === "" || to === null)) {
    return "-";
  }
  if (to === "-" || to === "" || to === null) {
    return `AS${from}`;
  }
  return `AS${from} -> AS${to}`;
}

export function formatBGPObservedTime(value) {
  const absolute = formatLocalDateTime(value);
  const relative = formatRelativeTime(value);
  if (!relative || absolute === "-") return absolute;
  return `${relative} (${absolute})`;
}

export function formatBGPASPath(asPath) {
  if (!Array.isArray(asPath) || asPath.length === 0) return "-";
  return asPath.map((asn) => `AS${asn}`).join(" -> ");
}

export function formatBGPObservedBy(collectors) {
  if (!Array.isArray(collectors) || collectors.length === 0) return "-";
  const preview = collectors.slice(0, 3).join(", ");
  if (collectors.length <= 3) {
    return `${collectors.length}个观测站 (${preview})`;
  }
  return `${collectors.length}个观测站 (${preview} 等)`;
}

export function formatBGPImpactedScope(regions) {
  if (!Array.isArray(regions) || regions.length === 0) return "-";
  const labels = regions
    .map((region) => {
      const city = region?.city || "";
      const country = region?.country || "";
      return city && country ? `${city}, ${country}` : city || country || "";
    })
    .filter(Boolean);

  if (labels.length === 0) return "-";
  if (labels.length <= 3) return labels.join(" / ");
  return `${labels.slice(0, 3).join(" / ")} 等${labels.length}地`;
}

function buildCollectorFeatureData(feature) {
  const coordinates = feature?.geometry?.coordinates || [];
  const [longitude, latitude] = coordinates;
  if (
    typeof latitude !== "number" ||
    typeof longitude !== "number" ||
    Number.isNaN(latitude) ||
    Number.isNaN(longitude)
  ) {
    return null;
  }

  const properties = feature?.properties || {};
  return {
    latitude,
    longitude,
    collector: properties.collector || "-",
    city: properties.city || "-",
    country: properties.country || "-",
    status: properties.status || "online",
  };
}

function spreadCollectorPositions(markers) {
  const groups = new Map();

  markers.forEach((marker) => {
    const key = `${marker.latitude.toFixed(4)}|${marker.longitude.toFixed(4)}`;
    if (!groups.has(key)) {
      groups.set(key, []);
    }
    groups.get(key).push(marker);
  });

  groups.forEach((group) => {
    if (group.length <= 1) return;

    const radius = 0.9;
    group.forEach((marker, index) => {
      const angle = (Math.PI * 2 * index) / group.length;
      marker.displayLatitude =
        marker.latitude + Math.sin(angle) * radius * 0.18;
      marker.displayLongitude =
        marker.longitude + Math.cos(angle) * radius * 0.18;
      marker.isSpread = true;
      marker.groupSize = group.length;
    });
  });

  markers.forEach((marker) => {
    if (marker.displayLatitude === undefined) {
      marker.displayLatitude = marker.latitude;
      marker.displayLongitude = marker.longitude;
      marker.isSpread = false;
      marker.groupSize = 1;
    }
  });

  return markers;
}

function buildAnomalyFeatureData(feature) {
  const coordinates = feature?.geometry?.coordinates || [];
  const [longitude, latitude] = coordinates;
  if (
    typeof latitude !== "number" ||
    typeof longitude !== "number" ||
    Number.isNaN(latitude) ||
    Number.isNaN(longitude)
  ) {
    return null;
  }

  const properties = feature?.properties || {};
  const severity = normalizeSeverity(properties.severity);
  const createdAt = properties.created_at || null;

  return {
    latitude,
    longitude,
    rawSeverity: properties.severity || severity,
    severity,
    collector: properties.collector || "-",
    city: properties.city || "-",
    country: properties.country || "-",
    source: properties.source || "-",
    anomaly_type: properties.anomaly_type || "-",
    status: properties.status || "-",
    prefix: properties.prefix || "-",
    origin_asn: properties.origin_asn ?? "-",
    new_origin_asn: properties.new_origin_asn ?? "-",
    as_path: Array.isArray(properties.as_path) ? properties.as_path : [],
    collectors: Array.isArray(properties.collectors) ? properties.collectors : [],
    collector_count: properties.collector_count ?? 1,
    impacted_regions: Array.isArray(properties.impacted_regions)
      ? properties.impacted_regions
      : [],
    confidence: properties.confidence ?? "-",
    summary: properties.summary || "-",
    created_at: formatLocalDateTime(createdAt),
    created_at_raw: createdAt,
    id:
      properties.id ||
      `${properties.collector || "unknown"}-${latitude}-${longitude}`,
  };
}

function clearMarkerArray(markers) {
  while (markers.length > 0) {
    const marker = markers.pop();
    marker.material?.dispose();
    bgpGroup.remove(marker);
  }
}

function clearGroup(group) {
  while (group.children.length > 0) {
    const child = group.children[group.children.length - 1];
    group.remove(child);
    if (child.geometry) child.geometry.dispose();
    if (child.material) child.material.dispose();
  }
}

function createSpriteMaterial({ color, opacity }) {
  return new THREE.SpriteMaterial({
    map: getMarkerTexture(),
    color,
    transparent: true,
    opacity,
    depthWrite: false,
    depthTest: true,
    blending: THREE.AdditiveBlending,
  });
}

function createOverlaySprite({ color, opacity, scale }) {
  const sprite = new THREE.Sprite(createSpriteMaterial({ color, opacity }));
  sprite.scale.setScalar(scale);
  return sprite;
}

function createArcLine(start, end, color) {
  const midpoint = start
    .clone()
    .add(end)
    .multiplyScalar(0.5)
    .normalize()
    .multiplyScalar(CONFIG.earthRadius + BGP_CONFIG.eventHubAltitudeOffset * 0.8);

  const curve = new THREE.QuadraticBezierCurve3(start, midpoint, end);
  const points = curve.getPoints(32);
  const geometry = new THREE.BufferGeometry().setFromPoints(points);
  const material = new THREE.LineBasicMaterial({
    color,
    transparent: true,
    opacity: 0.82,
    depthWrite: false,
    blending: THREE.AdditiveBlending,
  });

  return new THREE.Line(geometry, material);
}

function createCollectorMarker(markerData) {
  const sprite = new THREE.Sprite(
    createSpriteMaterial({
      color: BGP_CONFIG.collectorColor,
      opacity: BGP_CONFIG.opacity.collector,
    }),
  );

  const position = latLonToVector3(
    markerData.displayLatitude,
    markerData.displayLongitude,
    CONFIG.earthRadius + BGP_CONFIG.collectorAltitudeOffset,
  );

  sprite.position.copy(position);
  sprite.scale.setScalar(BGP_CONFIG.collectorScale);
  sprite.renderOrder = 3;
  sprite.visible = showBGP;
  sprite.userData = {
    type: "bgp_collector",
    state: "normal",
    baseScale: BGP_CONFIG.collectorScale,
    pulseOffset: Math.random() * Math.PI * 2,
    anomaly_count: 0,
    ...markerData,
  };

  collectorMarkers.push(sprite);
  bgpGroup.add(sprite);
}

function createAnomalyMarker(markerData) {
  const sprite = new THREE.Sprite(
    createSpriteMaterial({
      color: getSeverityColor(markerData.severity),
      opacity: BGP_CONFIG.opacity.normal,
    }),
  );

  const position = latLonToVector3(
    markerData.latitude,
    markerData.longitude,
    CONFIG.earthRadius + BGP_CONFIG.altitudeOffset,
  );

  const baseScale = BGP_CONFIG.baseScale * getSeverityScale(markerData.severity);
  sprite.position.copy(position);
  sprite.scale.setScalar(baseScale);
  sprite.renderOrder = 5;
  sprite.visible = showBGP;
  sprite.userData = {
    type: "bgp",
    state: "normal",
    baseScale,
    pulseOffset: Math.random() * Math.PI * 2,
    ...markerData,
  };

  anomalyMarkers.push(sprite);
  bgpGroup.add(sprite);
}

function dedupeAnomalies(features) {
  const latestByCollector = new Map();

  features.forEach((feature) => {
    const data = buildAnomalyFeatureData(feature);
    if (!data) return;

    anomalyCountByCollector.set(
      data.collector,
      (anomalyCountByCollector.get(data.collector) || 0) + 1,
    );

    const dedupeKey = `${data.collector}|${data.latitude.toFixed(4)}|${data.longitude.toFixed(4)}`;
    const previous = latestByCollector.get(dedupeKey);
    const currentTime = data.created_at_raw
      ? new Date(data.created_at_raw).getTime()
      : 0;
    const previousTime = previous?.created_at_raw
      ? new Date(previous.created_at_raw).getTime()
      : 0;

    if (!previous || currentTime >= previousTime) {
      latestByCollector.set(dedupeKey, data);
    }
  });

  return Array.from(latestByCollector.values())
    .sort((a, b) => {
      const timeA = a.created_at_raw ? new Date(a.created_at_raw).getTime() : 0;
      const timeB = b.created_at_raw ? new Date(b.created_at_raw).getTime() : 0;
      return timeB - timeA;
    })
    .slice(0, BGP_CONFIG.maxRenderedMarkers);
}

function applyCollectorCounts() {
  collectorMarkers.forEach((marker) => {
    marker.userData.anomaly_count =
      anomalyCountByCollector.get(marker.userData.collector) || 0;
  });
}

export async function loadBGPAnomalies(scene, earth) {
  clearBGPData(earth);

  const [collectorsResponse, anomaliesResponse] = await Promise.all([
    fetch(PATHS.bgpCollectorsApi),
    fetch(`${PATHS.bgpApi}?limit=${BGP_CONFIG.defaultFetchLimit}`),
  ]);

  if (!collectorsResponse.ok) {
    throw new Error(`BGP collectors HTTP ${collectorsResponse.status}`);
  }
  if (!anomaliesResponse.ok) {
    throw new Error(`BGP anomalies HTTP ${anomaliesResponse.status}`);
  }

  const collectorsPayload = await collectorsResponse.json();
  const anomaliesPayload = await anomaliesResponse.json();
  const collectorFeatures = Array.isArray(collectorsPayload?.features)
    ? collectorsPayload.features
    : [];
  const anomalyFeatures = Array.isArray(anomaliesPayload?.features)
    ? anomaliesPayload.features
    : [];

  totalAnomalyCount = anomaliesPayload?.count ?? anomalyFeatures.length;
  anomalyCountByCollector.clear();

  spreadCollectorPositions(
    collectorFeatures
    .map(buildCollectorFeatureData)
    .filter(Boolean),
  ).forEach(createCollectorMarker);

  dedupeAnomalies(anomalyFeatures).forEach(createAnomalyMarker);
  applyCollectorCounts();

  if (!bgpGroup.parent) {
    earth.add(bgpGroup);
  }
  if (!bgpOverlayGroup.parent) {
    earth.add(bgpOverlayGroup);
  }

  bgpGroup.visible = showBGP;
  bgpOverlayGroup.visible = showBGP;

  if (scene && !scene.children.includes(earth)) {
    scene.add(earth);
  }

  return {
    totalCount: totalAnomalyCount,
    renderedCount: anomalyMarkers.length,
    collectorCount: collectorMarkers.length,
  };
}

export function updateBGPVisualState(lockedObjectType, lockedObject) {
  const now = performance.now();
  const hasLockedLayer = Boolean(
    lockedObject && ["cable", "satellite", "bgp", "bgp_collector"].includes(lockedObjectType),
  );

  collectorMarkers.forEach((marker) => {
    const isLocked =
      (lockedObjectType === "bgp_collector" || lockedObjectType === "bgp") &&
      lockedObject?.userData?.collector === marker.userData.collector;
    const isHovered =
      marker.userData.state === "hover" || marker.userData.state === "linked";
    const pulse =
      0.5 +
      0.5 *
        Math.sin(
          now * BGP_CONFIG.collectorPulseSpeed + marker.userData.pulseOffset,
        );

    let scale = marker.userData.baseScale;
    let opacity = BGP_CONFIG.opacity.collector;

    if (isLocked) {
      scale *= 1.1 + 0.14 * pulse;
      opacity = BGP_CONFIG.opacity.collectorHover;
    } else if (isHovered) {
      scale *= 1.08;
      opacity = BGP_CONFIG.opacity.collectorHover;
    } else if (hasLockedLayer) {
      scale *= BGP_CONFIG.dimmedScale;
      opacity = BGP_CONFIG.opacity.dimmed;
    } else {
      scale *= 1 + 0.05 * pulse;
    }

    marker.scale.setScalar(scale);
    marker.material.opacity = opacity;
    marker.visible = showBGP;
  });

  anomalyMarkers.forEach((marker) => {
    const isLocked = lockedObjectType === "bgp" && lockedObject === marker;
    const isLinkedCollectorLocked =
      lockedObjectType === "bgp_collector" &&
      lockedObject?.userData?.collector === marker.userData.collector;
    const isOtherLocked = hasLockedLayer && !isLocked && !isLinkedCollectorLocked;
    const isHovered = marker.userData.state === "hover";
    const pulse =
      0.5 +
      0.5 * Math.sin(now * BGP_CONFIG.pulseSpeed + marker.userData.pulseOffset);

    let scale = marker.userData.baseScale;
    let opacity = BGP_CONFIG.opacity.normal;

    if (isLocked || isLinkedCollectorLocked) {
      scale *= 1 + BGP_CONFIG.lockedPulseAmplitude * pulse;
      opacity =
        BGP_CONFIG.opacity.lockedMin +
        (BGP_CONFIG.opacity.lockedMax - BGP_CONFIG.opacity.lockedMin) * pulse;
    } else if (isHovered) {
      scale *= BGP_CONFIG.hoverScale;
      opacity = BGP_CONFIG.opacity.hover;
    } else if (isOtherLocked) {
      scale *= BGP_CONFIG.dimmedScale;
      opacity = BGP_CONFIG.opacity.dimmed;
    } else {
      scale *= 1 + BGP_CONFIG.normalPulseAmplitude * pulse;
      opacity = BGP_CONFIG.opacity.normal;
    }

    marker.scale.setScalar(scale);
    marker.material.opacity = opacity;
    marker.visible = showBGP;
  });
}

export function setBGPMarkerState(marker, state = "normal") {
  if (!marker?.userData) return;
  if (marker.userData.type !== "bgp" && marker.userData.type !== "bgp_collector") {
    return;
  }
  marker.userData.state = state;
}

export function clearBGPSelection() {
  collectorMarkers.forEach((marker) => {
    marker.userData.state = "normal";
  });
  anomalyMarkers.forEach((marker) => {
    marker.userData.state = "normal";
  });
  clearBGPEventOverlay();
}

export function clearBGPData(earth) {
  clearMarkerArray(collectorMarkers);
  clearMarkerArray(anomalyMarkers);
  clearBGPEventOverlay();
  anomalyCountByCollector.clear();
  totalAnomalyCount = 0;

  if (earth && bgpGroup.parent === earth) {
    earth.remove(bgpGroup);
  }
  if (earth && bgpOverlayGroup.parent === earth) {
    earth.remove(bgpOverlayGroup);
  }
}

export function toggleBGP(show) {
  showBGP = Boolean(show);
  bgpGroup.visible = showBGP;
  bgpOverlayGroup.visible = showBGP;
  collectorMarkers.forEach((marker) => {
    marker.visible = showBGP;
  });
  anomalyMarkers.forEach((marker) => {
    marker.visible = showBGP;
  });
}

export function getShowBGP() {
  return showBGP;
}

export function getBGPMarkers() {
  return [...anomalyMarkers, ...collectorMarkers];
}

export function getBGPAnomalyMarkers() {
  return anomalyMarkers;
}

export function getBGPCollectorMarkers() {
  return collectorMarkers;
}

export function getBGPCount() {
  return totalAnomalyCount;
}

export function showBGPEventOverlay(marker, earth) {
  if (!marker?.userData || marker.userData.type !== "bgp" || !earth) return;

  clearBGPEventOverlay();

  const impactedRegions =
    Array.isArray(marker.userData.impacted_regions) &&
    marker.userData.impacted_regions.length > 0
      ? marker.userData.impacted_regions
      : [
          {
            collector: marker.userData.collector,
            city: marker.userData.city,
            country: marker.userData.country,
            latitude: marker.userData.latitude,
            longitude: marker.userData.longitude,
          },
        ];

  const validRegions = impactedRegions.filter(
    (region) =>
      typeof region?.latitude === "number" &&
      typeof region?.longitude === "number",
  );
  if (validRegions.length === 0) return;

  const averageLatitude =
    validRegions.reduce((sum, region) => sum + region.latitude, 0) /
    validRegions.length;
  const averageLongitude =
    validRegions.reduce((sum, region) => sum + region.longitude, 0) /
    validRegions.length;

  const hubPosition = latLonToVector3(
    averageLatitude,
    averageLongitude,
    CONFIG.earthRadius + BGP_CONFIG.eventHubAltitudeOffset,
  );
  const hub = createOverlaySprite({
    color: BGP_CONFIG.eventHubColor,
    opacity: 0.95,
    scale: BGP_CONFIG.eventHubScale,
  });
  hub.position.copy(hubPosition);
  hub.renderOrder = 6;
  bgpOverlayGroup.add(hub);

  const overlayItems = [hub];

  validRegions.forEach((region) => {
    const regionPosition = latLonToVector3(
      region.latitude,
      region.longitude,
      CONFIG.earthRadius + BGP_CONFIG.collectorAltitudeOffset + 0.3,
    );

    const link = createArcLine(regionPosition, hubPosition, BGP_CONFIG.linkColor);
    link.renderOrder = 4;
    bgpOverlayGroup.add(link);
    overlayItems.push(link);

    const halo = createOverlaySprite({
      color: BGP_CONFIG.regionColor,
      opacity: 0.24,
      scale: BGP_CONFIG.regionScale,
    });
    halo.position.copy(
      latLonToVector3(
        region.latitude,
        region.longitude,
        CONFIG.earthRadius + BGP_CONFIG.collectorAltitudeOffset - 0.1,
      ),
    );
    halo.renderOrder = 2;
    bgpOverlayGroup.add(halo);
    overlayItems.push(halo);
  });

  activeEventOverlay = overlayItems;
  bgpOverlayGroup.visible = showBGP;
}

export function clearBGPEventOverlay() {
  activeEventOverlay = null;
  clearGroup(bgpOverlayGroup);
}

export function getBGPLegendItems() {
  return [
    { color: "#6db7ff", label: "观测站" },
    { color: "#8af5ff", label: "事件连线 / 枢纽" },
    { color: "#2dd4bf", label: "影响区域" },
    { color: "#ff4d4f", label: "严重异常" },
    { color: "#ff9f43", label: "高危异常" },
    { color: "#ffd166", label: "中危异常" },
    { color: "#4dabf7", label: "低危异常" },
  ];
}