import * as Cesium from 'cesium';
import { describeInstallationFeedback } from '../../data/installationFeedback.js';
import {
  LAYER_ID,
  DISTANCE_PREFILTER_MARGIN_M,
  ANCHOR_REFRESH_M,
} from './policy.js';
import { formatNumber, t, tn } from '../../i18n/index.js';

// installationFeedback.js is shared with the HUD (src/loadingFeedback.js) and
// hands back msg()-marked English plus values; getStats translates them here.
function localizeInstallationFeedback(feedback) {
  if (feedback.text !== undefined) {
    const values = {};
    if (feedback.reason !== undefined) values.reason = t(feedback.reason);
    if (feedback.seconds !== undefined) values.seconds = feedback.seconds;
    return t(feedback.text, values);
  }
  const { count, km } = feedback;
  if (km) {
    const kmText = formatNumber(km);
    return count === 0
      ? t('No mapped sites within {km} km of the contact', { km: kmText })
      : tn(
          count,
          '{count} mapped site within {km} km of the contact',
          '{count} mapped sites within {km} km of the contact',
          { km: kmText },
        );
  }
  return count === 0
    ? t('No mapped sites in view')
    : tn(count, '{count} mapped site in view', '{count} mapped sites in view');
}

export function createControls({ state: layerState, services, parts, source }) {
  const methods = {
    id: LAYER_ID,

    name: 'Mapped Installations',

    icon: '⌖',

    source: 'OpenStreetMap + optional Google Maps Places',

    updateInterval: 0,

    statsRefreshInterval: 1000,

    visitNamedMarkers(visitor) {
      parts.namedMarkers.visit(visitor);
    },

    /** Request a one-shot Google Maps Places search around the current map view. */
    searchNearby() {
      layerState.googleSearchRequested = true;
      return parts.ingestion.loadInstallations();
    },

    /**
     * Load sites around a Contacts subject instead of the camera viewport.
     *
     * A follow or Cockpit camera moves every frame, so `moveEnd` never fires and
     * its view rectangle often reaches the horizon; a subject window is the
     * only area that answers "what is near this contact". The window moves
     * only after the subject travels ANCHOR_REFRESH_M, and cached tiles make
     * that cheap. Passing null returns the layer to viewport loading.
     * @param {Cesium.Cartesian3|{latitude:number, longitude:number}|null} position
     *   Subject position.
     * @returns {boolean} Whether a new load was scheduled.
     */
    setContextAnchor(position) {
      let next = null;
      if (position) {
        if (
          Number.isFinite(position.latitude) &&
          Number.isFinite(position.longitude)
        )
          next = { latitude: position.latitude, longitude: position.longitude };
        else {
          const carto = Cesium.Cartographic.fromCartesian(position);
          if (carto)
            next = {
              latitude: Cesium.Math.toDegrees(carto.latitude),
              longitude: Cesium.Math.toDegrees(carto.longitude),
            };
        }
      }
      // Keep the live centre even when the coarse fetch anchor has not moved.
      layerState.contextPosition = next
        ? Cesium.Cartesian3.fromDegrees(next.longitude, next.latitude)
        : null;
      const previous = layerState.contextAnchor;
      if (!next) {
        if (!previous) return false;
        layerState.contextAnchor = null;
        parts.viewport.scheduleLoad();
        return true;
      }
      if (
        previous &&
        parts.model.approximateSurfaceDistanceM(
          Cesium.Math.toRadians(previous.latitude),
          Cesium.Math.toRadians(previous.longitude),
          next.latitude,
          next.longitude,
        ) < ANCHOR_REFRESH_M
      )
        return false;
      layerState.contextAnchor = next;
      parts.viewport.scheduleLoad();
      return true;
    },

    getNearby(center, rangeM, maxCount = 50) {
      if (!center) return [];
      const range = Number.isFinite(rangeM) ? rangeM : Infinity;
      const centerCartographic = Cesium.Cartographic.fromCartesian(center);
      if (!centerCartographic) return [];
      const nearby = [];
      const approximateLimit = Number.isFinite(range)
        ? range * 1.03 + DISTANCE_PREFILTER_MARGIN_M
        : Infinity;
      for (const record of layerState.records) {
        if (record.kind !== 'installation') continue;
        if (
          parts.model.approximateSurfaceDistanceM(
            centerCartographic.latitude,
            centerCartographic.longitude,
            record.latitude,
            record.longitude,
          ) > approximateLimit
        )
          continue;
        // The awareness disk is projected onto the ground. Confirm candidates
        // with an exact ellipsoidal surface distance and reusable scratch state.
        layerState.distanceEndpointScratch.longitude = Cesium.Math.toRadians(
          record.longitude,
        );
        layerState.distanceEndpointScratch.latitude = Cesium.Math.toRadians(
          record.latitude,
        );
        layerState.distanceEndpointScratch.height = 0;
        layerState.distanceGeodesicScratch.setEndPoints(
          centerCartographic,
          layerState.distanceEndpointScratch,
        );
        const distanceM = layerState.distanceGeodesicScratch.surfaceDistance;
        if (!Number.isFinite(distanceM) || distanceM > range) continue;
        nearby.push({
          ...record,
          position: Cesium.Cartesian3.fromDegrees(
            record.longitude,
            record.latitude,
            parts.rendering.installationSurfaceHeightM(record),
          ),
          distanceM,
        });
      }
      nearby.sort((a, b) => a.distanceM - b.distanceM);
      return nearby.slice(
        0,
        Number.isFinite(maxCount) ? Math.max(1, Math.floor(maxCount)) : 50,
      );
    },

    /**
     * Select and frame a mapped installation from another contextual UI.
     * @param {string} id Source-backed installation id.
     * @returns {boolean} True when an available installation was focused.
     */
    focusById(id) {
      const record = layerState.recordById.get(String(id));
      if (!record || !layerState.viewer) return false;
      // No camera flight without a real selection: a flight plus a stale subject
      // reads as success to Context navigation and strands NEXT on this item.
      if (!parts.selection.selectRecord(record.id)) return false;
      layerState.viewer.camera.flyToBoundingSphere(
        new Cesium.BoundingSphere(
          Cesium.Cartesian3.fromDegrees(
            record.longitude,
            record.latitude,
            parts.rendering.installationSurfaceHeightM(record),
          ),
          18000,
        ),
        { duration: 1.4 },
      );
      return true;
    },

    /**
     * Snapshot loaded mapped installations as plain JSON-safe records for the analyst
     * query engine. On demand only (once per spoken query); [] while the
     * layer is off.
     * @param {number} [maxCount=Infinity] Most records to return.
     * @returns {Array<Object>} {id, name, class, kind, lat, lon}.
     */
    getAnalystRecords(maxCount = Infinity) {
      if (!layerState.enabled) return [];
      const result = [];
      for (const record of layerState.records || []) {
        if (result.length >= maxCount) break;
        if (
          !Number.isFinite(record.latitude) ||
          !Number.isFinite(record.longitude)
        )
          continue;
        result.push({
          id: record.name || record.id,
          name: record.name || null,
          class: record.class || null,
          kind: record.kind || null,
          lat: record.latitude,
          lon: record.longitude,
        });
      }
      return result;
    },

    getStats() {
      const namedMarkers = parts.namedMarkers?.stats();
      const subjectWindow =
        layerState.coverage?.kind === 'subject' &&
        layerState.contextPosition &&
        Number.isFinite(layerState.coverage.radiusM);
      const mappedCount = subjectWindow
        ? methods.getNearby(
            layerState.contextPosition,
            layerState.coverage.radiusM,
            layerState.records.length || 1,
          ).length
        : layerState.wide && namedMarkers
          ? namedMarkers.pointsOnScreen
          : layerState.records.filter(
              (record) => record.kind === 'installation',
            ).length;
      return {
        count:
          subjectWindow || layerState.wide
            ? mappedCount
            : layerState.records.length,
        namedInView: layerState.namedInView || 0,
        wide: Boolean(layerState.wide),
        ...namedMarkers,
        lastUpdate: layerState.lastUpdate,
        stale: layerState.stale,
        saturated: layerState.saturated,
        error: layerState.error,
        status: layerState.status,
        loading: layerState.loading,
        retryAt: layerState.retryAt,
        retrying: layerState.loading && Boolean(layerState.failureReason),
        failureReason: layerState.failureReason,
        statusMessage: localizeInstallationFeedback(
          describeInstallationFeedback({
            ...layerState,
            count: layerState.lastUpdate ? mappedCount : undefined,
            retrying: layerState.loading && Boolean(layerState.failureReason),
          }),
        ),
        loadingLabel: layerState.loading
          ? t('loading mapped installation context')
          : '',
        coverage: layerState.coverage,
        coverageLabel:
          layerState.coverage?.kind === 'subject'
            ? `WITHIN ${Math.round(layerState.coverage.radiusM / 1000)} KM`
            : 'CURRENT VIEWPORT ONLY',
      };
    },
  };

  return { methods };
}