// Master of Vega — the star map.
//
// Layer order (each one a SEPARATE root container, because a Phaser Container
// renders its children in insertion order and ignores their depth — putting
// these in one container and setting .depth would silently do nothing):
//
//   nebula -> parallax starfield -> territory field -> starlanes
//   -> range darkness -> stars -> fleets -> labels
//
// Everything from `territory` down lives inside `this.root`, which is the one
// object that gets scaled and moved for pan and zoom. The nebula and the
// parallax layers are screen-space and move at their own rates.

import * as Phaser from 'phaser';
import { GAME_HEIGHT, GAME_WIDTH } from '../../config.js';
import { Tooltip } from '../../ui/Tooltip.js';
import { makeNebula } from './VegaNebula.js';
import { PARSEC_PX, parsecs, mulberry32 } from './VegaGalaxyGen.js';
import {
  coloniesAt, empireColonies, fleetEta, habitableForEmpire,
} from './VegaLogic.js';
import { starFrame } from './VegaArt.js';
import { buildZoomLadder, DEFAULT_ZOOM_INDEX } from './VegaZoom.js';
import { describeStarTooltip } from './VegaTooltips.js';
import { ORBIT } from './VegaScreens.js';

const FONT = '"Julius Sans One"';

// Per-empire colony roster block drawn up-left of a colonized star. Sizing
// is tuned to clear both the star's own ownership ring and the in-transit
// fleet marker/comet trail, which already occupies the same upper-left
// quadrant at (star.x - 26, star.y - 22).
const COLONY_INFO_GAP_X = 112;
const COLONY_INFO_GAP_Y = 36;
const COLONY_INFO_BAR_H = 12;
const COLONY_INFO_BAR_TEXT_GAP = 8;
const COLONY_INFO_GROUP_GAP = 20;
const COLONY_INFO_MIN_BAR_W = 80;
const COLONY_INFO_TEXT_SIZE = 26;

// The range and territory fields are painted into low-resolution
// RenderTextures and scaled up. A huge galaxy is 5400px wide — past the safe
// single-texture size — and the upscale blur is exactly the soft edge both
// effects want anyway, so the low resolution is a feature, not a compromise.
const FIELD_DIV = 6;

function ensureSoftDisc(scene, key, size) {
  if (scene.textures.exists(key)) return key;
  const tex = scene.textures.createCanvas(key, size, size);
  const ctx = tex.getContext();
  const g = ctx.createRadialGradient(size / 2, size / 2, size * 0.04, size / 2, size / 2, size / 2);
  g.addColorStop(0, 'rgba(255,255,255,1)');
  g.addColorStop(0.55, 'rgba(255,255,255,0.85)');
  g.addColorStop(1, 'rgba(255,255,255,0)');
  ctx.fillStyle = g;
  ctx.fillRect(0, 0, size, size);
  tex.refresh();
  return key;
}

export default class VegaStarMap {
  constructor(scene, rules, state, artKeys, callbacks = {}) {
    this.scene = scene;
    this.rules = rules;
    this.state = state;
    this.art = artKeys;
    this.cb = callbacks;
    this.viewerIdx = state.humanIndex;

    this.zooms = buildZoomLadder(state.galaxy.width, state.galaxy.height);
    this.zoomIndex = Math.min(DEFAULT_ZOOM_INDEX, this.zooms.length - 1);
    this.zoom = this.zooms[this.zoomIndex];
    this.selectedStar = -1;
    this.selectedFleet = null;
    this.routePreview = null;
    this.hoverStar = -1;
    this.rangeDirty = true;
    this.territoryDirty = true;
    this.time = 0;

    const galaxy = state.galaxy;
    this.worldW = galaxy.width;
    this.worldH = galaxy.height;

    ensureSoftDisc(scene, 'vega-soft-disc', 256);

    this.tooltip = new Tooltip(scene, { depth: 70 });

    // --- screen-space backdrop
    this.bgLayer = scene.add.container(0, 0).setDepth(0);
    this.nebula = makeNebula(scene, this.bgLayer, {
      seed: galaxy.seed, shapeId: galaxy.shapeId, density: 1,
    });

    this.starfield = scene.add.container(0, 0).setDepth(1);
    this.parallax = [];
    this.buildParallax(galaxy.seed);

    // --- world-space
    this.root = scene.add.container(0, 0).setDepth(2);

    this.fieldW = Math.max(2, Math.ceil(this.worldW / FIELD_DIV));
    this.fieldH = Math.max(2, Math.ceil(this.worldH / FIELD_DIV));

    this.territoryRT = scene.add.renderTexture(0, 0, this.fieldW, this.fieldH)
      .setOrigin(0, 0).setScale(FIELD_DIV).setAlpha(0.5)
      .setBlendMode(Phaser.BlendModes.ADD);
    this.root.add(this.territoryRT);

    this.laneGfx = scene.add.graphics();
    this.root.add(this.laneGfx);

    this.rangeRT = scene.add.renderTexture(0, 0, this.fieldW, this.fieldH)
      .setOrigin(0, 0).setScale(FIELD_DIV);
    this.root.add(this.rangeRT);

    // Sits behind starLayer (insertion order) so every star sprite paints
    // over the connecting lines this layer draws to its own center.
    this.colonyInfoLayer = scene.add.container(0, 0);
    this.root.add(this.colonyInfoLayer);

    this.starLayer = scene.add.container(0, 0);
    this.root.add(this.starLayer);
    // The selection reticle sits above the stars and below the fleet markers,
    // so a fleet parked over its own star is never hidden by its own highlight.
    this.selGfx = scene.add.graphics();
    this.root.add(this.selGfx);
    this.routeGfx = scene.add.graphics();
    this.root.add(this.routeGfx);
    this.fleetLayer = scene.add.container(0, 0);
    this.root.add(this.fleetLayer);
    this.labelLayer = scene.add.container(0, 0);
    this.root.add(this.labelLayer);

    this.buildStars();
    this.drawLanes();
    this.refresh();
    this.centerOn(state.galaxy.homeIdx[Math.max(0, this.viewerIdx)] ?? 0);

    this.bindInput();
  }

  // Semantic zoom is keyed to the LADDER INDEX, not an absolute scale. The same
  // scale means different things in different galaxies now that the ladder is
  // built per galaxy — 0.74 is fully zoomed out on a small map and mid-range on
  // a huge one — so an absolute threshold would put the two in different modes
  // while showing the same amount of sky.
  get isFarZoom() { return this.zoomIndex === 0 && this.zooms.length > 1; }
  get isNearZoom() { return this.zoomIndex >= this.zooms.length - 2; }

  // ------------------------------------------------------------------ setup

  buildParallax(seed) {
    const rnd = mulberry32(seed * 7919 + 13);
    // Four layers at different rates. The nearest layer is sparse and bright,
    // the far ones dense and dim, which is what sells depth on a pan.
    const layers = [
      { count: 260, rate: 0.08, size: 1.0, alpha: 0.35 },
      { count: 180, rate: 0.16, size: 1.4, alpha: 0.5 },
      { count: 110, rate: 0.28, size: 1.9, alpha: 0.7 },
      { count: 45, rate: 0.44, size: 2.6, alpha: 0.9 },
    ];
    for (const spec of layers) {
      const g = this.scene.add.graphics();
      const stars = [];
      for (let i = 0; i < spec.count; i += 1) {
        const x = rnd() * GAME_WIDTH * 1.6 - GAME_WIDTH * 0.3;
        const y = rnd() * GAME_HEIGHT * 1.6 - GAME_HEIGHT * 0.3;
        const tone = 0.65 + rnd() * 0.35;
        stars.push({ x, y, tone });
      }
      for (const s of stars) {
        const c = Math.round(255 * s.tone);
        g.fillStyle((c << 16) | (c << 8) | 255, spec.alpha);
        g.fillCircle(s.x, s.y, spec.size);
      }
      this.starfield.add(g);
      this.parallax.push({ g, rate: spec.rate, baseX: 0, baseY: 0 });
    }
  }

  buildStars() {
    const { rules, state, scene } = this;
    this.starSprites = [];
    for (const star of state.galaxy.stars) {
      const cls = rules.starClasses[star.classId];
      const container = scene.add.container(star.x, star.y);

      const frame = Math.max(0, starFrame(rules, star.classId));
      const body = scene.add.image(0, 0, this.art.stars, frame);
      const scale = (cls.radius * 5.5) / 192;
      body.setScale(scale);
      body.setBlendMode(cls.special === 'blackhole' ? Phaser.BlendModes.NORMAL : Phaser.BlendModes.ADD);
      container.add(body);

      // Binary companion and pulsar beam are animated in update().
      let companion = null;
      if (cls.special === 'binary') {
        companion = scene.add.image(0, 0, this.art.stars, frame);
        companion.setScale(scale * 0.55).setBlendMode(Phaser.BlendModes.ADD);
        container.add(companion);
      }

      // Ownership ring, drawn only when the system is settled.
      const ring = scene.add.graphics();
      container.add(ring);

      // Generous hit area — these are small targets at low zoom.
      const hit = scene.add.circle(0, 0, 30, 0xffffff, 0.001).setInteractive({ useHandCursor: true });
      hit.on('pointerover', () => { this.hoverStar = star.idx; this.cb.onStarHover?.(star.idx); });
      hit.on('pointerout', () => { if (this.hoverStar === star.idx) this.hoverStar = -1; this.cb.onStarHover?.(-1); });
      hit.on('pointerup', (p) => { if (!this.dragged) this.cb.onStarClick?.(star.idx, p); });
      this.tooltip.attachTo(hit, () => {
        const viewer = this.viewerIdx >= 0 ? this.state.empires[this.viewerIdx] : null;
        return describeStarTooltip(this.rules, this.state, viewer, star.idx);
      });
      container.add(hit);

      this.starLayer.add(container);
      this.starSprites.push({ star, container, body, companion, ring, cls, phase: star.companionAngle });
    }
  }

  drawLanes() {
    const g = this.laneGfx;
    g.clear();
    for (const lane of this.state.galaxy.lanes) {
      const a = this.state.galaxy.stars[lane.a];
      const b = this.state.galaxy.stars[lane.b];
      // Long lanes fade out — they are geometrically real but visually noise.
      const alpha = Math.max(0.05, 0.3 - lane.parsecs * 0.012);
      g.lineStyle(1.5, 0x4b6fa8, alpha);
      g.lineBetween(a.x, a.y, b.x, b.y);
    }
  }

  // ------------------------------------------------------------- the fields

  // "Explored as light": the galaxy is covered in darkness, and each star the
  // player has actually explored (colonised, or had a fleet visit) gets a soft
  // patch erased around it. Deliberately NOT fuel range — reachability is left
  // for the player to work out by trial and error rather than telegraphed on
  // the map.
  // A scratch image reused for every stamp. RenderTexture.erase()/draw() honour
  // a game object's scale and tint, but NOT a bare texture key's — a key is
  // always stamped at its native 256px. Everything here needs a radius that
  // varies, so it all goes through this one object.
  stamp(scale, tint = null, alpha = 1) {
    if (!this._stamp) {
      this._stamp = this.scene.make.image({ key: 'vega-soft-disc', add: false }).setOrigin(0.5, 0.5);
    }
    this._stamp.setScale(scale).setAlpha(alpha);
    if (tint === null) this._stamp.clearTint();
    else this._stamp.setTint(tint);
    return this._stamp;
  }

  redrawRange() {
    this.rangeDirty = false;
    const rt = this.rangeRT;
    rt.clear();
    if (this.viewerIdx < 0) return; // observer mode sees the whole galaxy
    rt.fill(0x04050b, 0.8);

    const emp = this.state.empires[this.viewerIdx];
    if (!emp) return;
    // One soft disc per explored star — sized to clear just that star's own
    // neighbourhood, not to bridge gaps into a "sphere of influence" the way
    // the old fuel-range version did (that would re-imply territory the
    // player hasn't actually scouted).
    const radius = PARSEC_PX * 1.1;
    const img = this.stamp((radius * 2) / 256 / FIELD_DIV);
    for (const star of this.state.galaxy.stars) {
      if (!emp.explored[star.idx]) continue;
      rt.erase(img, star.x / FIELD_DIV, star.y / FIELD_DIV);
    }
  }

  // Soft empire colour fields instead of hard borders.
  redrawTerritory() {
    this.territoryDirty = false;
    const rt = this.territoryRT;
    rt.clear();
    const viewer = this.viewerIdx >= 0 ? this.state.empires[this.viewerIdx] : null;
    for (const colony of this.state.colonies) {
      const emp = this.state.empires[colony.empireIdx];
      if (!emp) continue;
      if (viewer && !viewer.explored[colony.starIdx]) continue;
      const star = this.state.galaxy.stars[colony.starIdx];
      // Bigger colonies project further, so a homeworld anchors a region and an
      // outpost only tints its own system.
      const spread = Phaser.Math.Clamp(0.7 + colony.pop / 90, 0.7, 2.4);
      const radius = PARSEC_PX * 1.8 * spread;
      const img = this.stamp((radius * 2) / 256 / FIELD_DIV,
        Phaser.Display.Color.HexStringToColor(emp.color).color, 0.85);
      rt.draw(img, star.x / FIELD_DIV, star.y / FIELD_DIV);
    }
  }

  // -------------------------------------------------------------- rendering

  refresh() {
    this.redrawRange();
    this.redrawTerritory();
    this.refreshStars();
    this.refreshColonyInfo();
    this.refreshFleets();
    this.refreshLabels();
  }

  refreshStars() {
    const { state, rules } = this;
    const viewer = this.viewerIdx >= 0 ? state.empires[this.viewerIdx] : null;
    for (const s of this.starSprites) {
      const explored = !viewer || viewer.explored[s.star.idx];
      // Unexplored stars stay visible (dimmed) at every zoom level so there is
      // always something to hover/click for the UNEXPLORED tooltip and a scout
      // target — only their name, ring and system contents are hidden.
      s.container.setVisible(true);
      s.body.setAlpha(explored ? 1 : 0.25);

      const cols = coloniesAt(state, s.star.idx);
      s.ring.clear();
      if (!cols.length || !explored) continue;
      const owner = state.empires[cols[0].empireIdx];
      const colour = Phaser.Display.Color.HexStringToColor(owner.color).color;
      s.ring.lineStyle(2.5, colour, 0.95);
      s.ring.strokeCircle(0, 0, s.cls.radius * 2.2 + 8);
      if (cols.some((c) => c.capital)) {
        s.ring.lineStyle(1.5, colour, 0.6);
        s.ring.strokeCircle(0, 0, s.cls.radius * 2.2 + 14);
      }
    }
  }

  /**
   * Per-empire colony roster stacked up-left of a colonized star: a thick
   * owner-colored bar over a "name (pop. N)" list, one group per empire that
   * holds a colony at the star, each with its own line running to the star's
   * center. Only shown at the closest zoom tier — same density tier as the
   * "N worlds · M habitable" subtext — to keep the mid/far zoom map legible.
   */
  refreshColonyInfo() {
    this.colonyInfoLayer.removeAll(true);
    if (this.isFarZoom || !this.isNearZoom) return;
    const { state } = this;
    const viewer = this.viewerIdx >= 0 ? state.empires[this.viewerIdx] : null;
    const textSize = Math.round(COLONY_INFO_TEXT_SIZE / Math.max(0.7, this.zoom));

    for (const s of this.starSprites) {
      if (viewer && !viewer.explored[s.star.idx]) continue;
      const cols = coloniesAt(state, s.star.idx);
      if (!cols.length) continue;

      const groups = [];
      for (const emp of state.empires) {
        const own = cols.filter((c) => c.empireIdx === emp.idx).sort((a, b) => a.orbit - b.orbit);
        if (!own.length) continue;
        const text = this.scene.add.text(0, 0, own.map((c) => (
          `${s.star.name} ${ORBIT[c.orbit] ?? c.orbit + 1} (pop. ${c.pop.toFixed(1)})`
        )).join('\n'), {
          fontFamily: FONT, fontSize: `${textSize}px`, color: '#f0f4fa', lineSpacing: 2,
        }).setOrigin(1, 0);
        groups.push({ emp, text });
      }
      if (!groups.length) continue;

      const barWidth = Math.max(COLONY_INFO_MIN_BAR_W, ...groups.map((g) => g.text.width));
      const blockRightX = s.star.x - COLONY_INFO_GAP_X;
      const totalHeight = groups.reduce((h, g) => (
        h + COLONY_INFO_BAR_H + COLONY_INFO_BAR_TEXT_GAP + g.text.height
      ), 0) + COLONY_INFO_GROUP_GAP * (groups.length - 1);
      let y = s.star.y - COLONY_INFO_GAP_Y - totalHeight;

      const lines = this.scene.add.graphics();
      this.colonyInfoLayer.add(lines);
      for (const g of groups) {
        const colour = Phaser.Display.Color.HexStringToColor(g.emp.color).color;
        const bar = this.scene.add.rectangle(
          blockRightX - barWidth / 2, y + COLONY_INFO_BAR_H / 2, barWidth, COLONY_INFO_BAR_H, colour,
        ).setStrokeStyle(2, 0x000000, 0.85);
        this.colonyInfoLayer.add(bar);
        lines.lineStyle(3, colour, 0.7);
        lines.lineBetween(blockRightX, y + COLONY_INFO_BAR_H / 2, s.star.x, s.star.y);

        g.text.setPosition(blockRightX, y + COLONY_INFO_BAR_H + COLONY_INFO_BAR_TEXT_GAP);
        this.colonyInfoLayer.add(g.text);

        y += COLONY_INFO_BAR_H + COLONY_INFO_BAR_TEXT_GAP + g.text.height + COLONY_INFO_GROUP_GAP;
      }
    }
  }

  refreshFleets() {
    this.fleetLayer.removeAll(true);
    const { state, rules } = this;
    const viewer = this.viewerIdx >= 0 ? state.empires[this.viewerIdx] : null;
    this.fleetMarkers = [];

    for (const fleet of state.fleets) {
      const emp = state.empires[fleet.empireIdx];
      if (!emp) continue;
      const own = fleet.empireIdx === this.viewerIdx;
      let x;
      let y;
      if (fleet.starIdx >= 0) {
        const star = state.galaxy.stars[fleet.starIdx];
        if (viewer && !own && !viewer.explored[fleet.starIdx]) continue;
        x = star.x + 26;
        y = star.y - 22;
      } else {
        const a = state.galaxy.stars[fleet.fromStar];
        const b = state.galaxy.stars[fleet.toStar];
        if (!a || !b) continue;
        if (viewer && !own && !viewer.explored[fleet.toStar]) continue;
        const t = fleet.total > 0 ? Phaser.Math.Clamp(fleet.progress / fleet.total, 0, 1) : 0;
        // Offset up-left of the lane so a fleet just leaving its origin star
        // doesn't sit directly on top of it and block the star's own click target.
        x = a.x + (b.x - a.x) * t - 26;
        y = a.y + (b.y - a.y) * t - 22;
      }

      const colour = Phaser.Display.Color.HexStringToColor(emp.color).color;
      const c = this.scene.add.container(x, y);

      // Fleets in transit render as a comet: a bright head with a trail back
      // along the lane, plus tick marks for the turns still to run.
      if (fleet.starIdx < 0) {
        const a = state.galaxy.stars[fleet.fromStar];
        const b = state.galaxy.stars[fleet.toStar];
        const ang = Math.atan2(b.y - a.y, b.x - a.x);
        const trail = this.scene.add.graphics();
        for (let i = 1; i <= 8; i += 1) {
          trail.fillStyle(colour, 0.42 * (1 - i / 9));
          trail.fillCircle(-Math.cos(ang) * i * 7, -Math.sin(ang) * i * 7, 5 - i * 0.45);
        }
        c.add(trail);
        if (own) {
          const eta = fleetEta(rules, state, fleet);
          const label = this.scene.add.text(0, -20, `${Number.isFinite(eta) ? eta : '—'}`, {
            fontFamily: FONT, fontSize: '15px', color: '#cfe3ff',
          }).setOrigin(0.5);
          c.add(label);
        }
      }

      const head = this.scene.add.graphics();
      head.fillStyle(colour, 1);
      head.fillCircle(0, 0, 6);
      head.lineStyle(1.5, 0xffffff, 0.75);
      head.strokeCircle(0, 0, 6);
      c.add(head);

      const hit = this.scene.add.circle(0, 0, 16, 0xffffff, 0.001).setInteractive({ useHandCursor: true });
      hit.on('pointerup', () => { if (!this.dragged) this.cb.onFleetClick?.(fleet); });
      hit.on('pointerover', () => this.cb.onFleetHover?.(fleet));
      hit.on('pointerout', () => this.cb.onFleetHover?.(null));
      c.add(hit);

      this.fleetLayer.add(c);
      this.fleetMarkers.push({ fleet, container: c });
    }
  }

  refreshLabels() {
    this.labelLayer.removeAll(true);
    const { state } = this;
    const viewer = this.viewerIdx >= 0 ? state.empires[this.viewerIdx] : null;
    // At the widest zoom the map shows empire names over their territory
    // instead of a fog of unreadable star labels.
    if (this.isFarZoom) {
      for (const emp of state.empires) {
        if (!emp.alive) continue;
        const cols = empireColonies(state, emp.idx);
        if (!cols.length) continue;
        if (viewer && emp.idx !== viewer.idx && !viewer.contacted[emp.idx]) continue;
        const cx = cols.reduce((t, c) => t + state.galaxy.stars[c.starIdx].x, 0) / cols.length;
        const cy = cols.reduce((t, c) => t + state.galaxy.stars[c.starIdx].y, 0) / cols.length;
        const t = this.scene.add.text(cx, cy, emp.name.toUpperCase(), {
          fontFamily: FONT, fontSize: `${Math.round(46 / this.zoom)}px`, color: emp.color,
        }).setOrigin(0.5).setAlpha(0.55);
        this.labelLayer.add(t);
      }
      return;
    }

    for (const s of this.starSprites) {
      if (viewer && !viewer.explored[s.star.idx]) continue;
      const cols = coloniesAt(state, s.star.idx);
      const owner = cols.length ? state.empires[cols[0].empireIdx] : null;
      const label = this.scene.add.text(s.star.x, s.star.y + s.cls.radius * 2.2 + 14, s.star.name, {
        fontFamily: FONT, fontSize: `${Math.round(17 / Math.max(0.7, this.zoom))}px`,
        color: owner ? owner.color : '#9fb3cc',
      }).setOrigin(0.5, 0);
      this.labelLayer.add(label);

      // Closest zoom adds the system's contents.
      if (this.isNearZoom) {
        // "Habitable" here means settleable at the viewer's CURRENT
        // planetology, not just the planet type's static ceiling — a Radiated
        // world is colonizable in principle but still shows as 0/1 until tech
        // catches up, matching what the system view's colonize button says.
        const habitable = viewer
          ? s.star.planets.filter((p, orbit) => habitableForEmpire(this.rules, state, viewer.idx, s.star.idx, orbit)).length
          : s.star.planets.filter((p) => this.rules.planetTypes[p.typeId].colonizable).length;
        if (s.star.planets.length) {
          const sub = this.scene.add.text(
            s.star.x, s.star.y + s.cls.radius * 2.2 + 32,
            `${s.star.planets.length} worlds · ${habitable} habitable`,
            { fontFamily: FONT, fontSize: '13px', color: '#6f8199' },
          ).setOrigin(0.5, 0);
          this.labelLayer.add(sub);
        }
      }
    }
  }

  // ---------------------------------------------------------- selection

  /** Ring the system the command panel is currently talking about. -1 clears. */
  setSelectedStar(idx) {
    this.selectedStar = idx ?? -1;
    this.selectedFleet = null;
    this.clearRoutePreview();
    this.drawSelection();
  }

  /**
   * Ring a specific fleet marker instead of the star it happens to be at.
   * A fleet that is already underway (or has a standing order) gets the same
   * flowing route drawn to its live destination — tracked by reference so it
   * keeps pace with the fleet as it moves, not a snapshot of where it was.
   */
  setSelectedFleet(fleet) {
    this.selectedFleet = fleet ?? null;
    this.selectedStar = -1;
    if (fleet && fleet.toStar >= 0) {
      this.routePreview = { fleet };
    } else {
      this.routePreview = null;
    }
    this.routeGfx.clear();
    this.drawSelection();
    if (this.routePreview) this.drawRoutePreview();
  }

  /** Flowing dashes from `fromIdx` to `toIdx` — the route a pending order will fly. */
  setRoutePreview(fromIdx, toIdx) {
    if (fromIdx == null || toIdx == null || fromIdx < 0 || toIdx < 0) {
      this.clearRoutePreview();
      return;
    }
    this.routePreview = { from: fromIdx, to: toIdx };
    this.drawRoutePreview();
  }

  clearRoutePreview() {
    this.routePreview = null;
    this.routeGfx.clear();
  }

  /** Resolve the preview's start/end points — either a fixed star pair (a
   * pending click-to-order) or a live fleet reference (an underway fleet
   * tracked to its destination as it flies). */
  resolveRouteEndpoints() {
    const rp = this.routePreview;
    if (!rp) return null;
    if (rp.fleet) {
      const f = rp.fleet;
      if (!this.state.fleets.includes(f) || f.toStar < 0) return null;
      const dest = this.state.galaxy.stars[f.toStar];
      if (!dest) return null;
      let ax;
      let ay;
      if (f.starIdx >= 0) {
        const star = this.state.galaxy.stars[f.starIdx];
        if (!star) return null;
        // Match the fleet marker's own offset from the star it sits at.
        ax = star.x + 26;
        ay = star.y - 22;
      } else {
        const from = this.state.galaxy.stars[f.fromStar];
        if (!from) return null;
        const t = f.total > 0 ? Phaser.Math.Clamp(f.progress / f.total, 0, 1) : 0;
        ax = from.x + (dest.x - from.x) * t - 26;
        ay = from.y + (dest.y - from.y) * t - 22;
      }
      return {
        ax, ay, bx: dest.x, by: dest.y,
      };
    }
    const from = this.state.galaxy.stars[rp.from];
    const to = this.state.galaxy.stars[rp.to];
    if (!from || !to) return null;
    return {
      ax: from.x, ay: from.y, bx: to.x, by: to.y,
    };
  }

  drawRoutePreview() {
    const g = this.routeGfx;
    g.clear();
    const pts = this.resolveRouteEndpoints();
    if (!pts) return;
    const a = { x: pts.ax, y: pts.ay };
    const b = { x: pts.bx, y: pts.by };
    const dx = b.x - a.x;
    const dy = b.y - a.y;
    const len = Math.hypot(dx, dy);
    if (len < 1) return;
    const ux = dx / len;
    const uy = dy / len;

    // Marching dashes: a fixed dash/gap pattern whose phase slides toward the
    // destination, reading as a current flowing along the route rather than a
    // static line — the "ship will fly this way" cue the ring around the
    // target star used to give less directly.
    const dash = 22;
    const gap = 16;
    const period = dash + gap;
    const speed = 90;
    // d advances with time (not -phase) so the dashes drift from `a` toward
    // `b` — matching the ship's actual direction of travel, not the reverse.
    const phase = ((this.time / 1000) * speed) % period;
    g.lineStyle(3, 0x9fd8ff, 0.85);
    for (let d = phase - period; d < len; d += period) {
      const s = Math.max(d, 0);
      const e = Math.min(d + dash, len);
      if (e <= s) continue;
      g.beginPath();
      g.moveTo(a.x + ux * s, a.y + uy * s);
      g.lineTo(a.x + ux * e, a.y + uy * e);
      g.strokePath();
    }

    // Arrowhead planted on the destination star, pointing along the route.
    const ang = Math.atan2(dy, dx);
    const ah = 11;
    const tip = { x: b.x - ux * 6, y: b.y - uy * 6 };
    g.fillStyle(0x9fd8ff, 0.9);
    g.beginPath();
    g.moveTo(tip.x, tip.y);
    g.lineTo(tip.x - Math.cos(ang - 2.6) * ah, tip.y - Math.sin(ang - 2.6) * ah);
    g.lineTo(tip.x - Math.cos(ang + 2.6) * ah, tip.y - Math.sin(ang + 2.6) * ah);
    g.closePath();
    g.fillPath();
  }

  drawSelection() {
    const g = this.selGfx;
    g.clear();
    let cx;
    let cy;
    let r;
    if (this.selectedFleet) {
      const marker = this.fleetMarkers?.find((m) => m.fleet === this.selectedFleet);
      if (!marker) return;
      cx = marker.container.x;
      cy = marker.container.y;
      r = 20;
    } else {
      const s = this.starSprites?.[this.selectedStar];
      if (!s) return;
      cx = s.star.x;
      cy = s.star.y;
      r = s.cls.radius * 2.2 + 20;
    }
    // Four arcs rather than a circle: a broken reticle stays legible on top of
    // an ownership ring, which a second full circle would not.
    const spin = (this.time / 1000) * 0.5;
    g.lineStyle(2, 0x9fd8ff, 0.95);
    for (let i = 0; i < 4; i += 1) {
      const a = spin + (i * Math.PI) / 2;
      g.beginPath();
      g.arc(cx, cy, r, a, a + 0.7);
      g.strokePath();
    }
  }

  // ------------------------------------------------------------- animation

  update(_time, delta) {
    this.time += delta;
    const t = this.time / 1000;

    if (this.selectedStar >= 0 || this.selectedFleet) this.drawSelection();
    if (this.routePreview) this.drawRoutePreview();

    for (const s of this.starSprites) {
      if (s.cls.special === 'pulsar') {
        s.body.setRotation(t * 1.4);
      } else if (s.cls.special === 'binary' && s.companion) {
        const a = s.phase + t * 0.7;
        const r = s.cls.radius * 1.9;
        s.companion.setPosition(Math.cos(a) * r, Math.sin(a) * r * 0.55);
        s.body.setPosition(-Math.cos(a) * r * 0.35, -Math.sin(a) * r * 0.2);
      } else if (s.cls.special === 'blackhole') {
        s.body.setRotation(-t * 0.35);
      } else {
        // A slow breath so the map is never completely static.
        s.body.setAlpha(0.88 + Math.sin(t * 1.2 + s.star.idx) * 0.12);
      }
    }

    // Parallax follows the camera, each layer at its own rate.
    for (const layer of this.parallax) {
      layer.g.setPosition(this.root.x * layer.rate, this.root.y * layer.rate);
    }
  }

  // ---------------------------------------------------------------- camera

  // Keep the viewport inside the galaxy. The old version allowed 160px of slack
  // on every side, which let the player drag empty space into view even at a
  // zoom that covered the screen — the same complaint as zooming out too far,
  // just reached a different way.
  clampPan() {
    const w = this.worldW * this.zoom;
    const h = this.worldH * this.zoom;
    // At the bottom of the ladder w/h equal the viewport, so both bounds
    // collapse to a single value and the map sits locked and centred.
    this.root.x = w >= GAME_WIDTH
      ? Phaser.Math.Clamp(this.root.x, GAME_WIDTH - w, 0)
      : (GAME_WIDTH - w) / 2;
    this.root.y = h >= GAME_HEIGHT
      ? Phaser.Math.Clamp(this.root.y, GAME_HEIGHT - h, 0)
      : (GAME_HEIGHT - h) / 2;
  }

  applyZoom(newIndex, focusX = GAME_WIDTH / 2, focusY = GAME_HEIGHT / 2) {
    const idx = Phaser.Math.Clamp(newIndex, 0, this.zooms.length - 1);
    if (idx === this.zoomIndex) return;
    const old = this.zoom;
    const next = this.zooms[idx];
    // Keep whatever is under the cursor under the cursor.
    const worldX = (focusX - this.root.x) / old;
    const worldY = (focusY - this.root.y) / old;
    this.zoomIndex = idx;
    this.zoom = next;
    this.root.setScale(next);
    this.root.x = focusX - worldX * next;
    this.root.y = focusY - worldY * next;
    this.clampPan();
    this.refreshLabels();
    this.refreshStars();
    this.refreshColonyInfo();
    this.cb.onZoom?.(next);
  }

  centerOn(starIdx) {
    const star = this.state.galaxy.stars[starIdx];
    if (!star) return;
    this.root.setScale(this.zoom);
    this.root.x = GAME_WIDTH / 2 - star.x * this.zoom;
    this.root.y = GAME_HEIGHT / 2 - star.y * this.zoom;
    this.clampPan();
  }

  panToStar(starIdx, duration = 420) {
    const star = this.state.galaxy.stars[starIdx];
    if (!star) return;
    const targetX = GAME_WIDTH / 2 - star.x * this.zoom;
    const targetY = GAME_HEIGHT / 2 - star.y * this.zoom;
    this.scene.tweens.add({
      targets: this.root,
      x: targetX,
      y: targetY,
      duration,
      ease: 'Sine.easeInOut',
      onComplete: () => this.clampPan(),
    });
  }

  bindInput() {
    const scene = this.scene;
    this.dragged = false;
    let dragging = false;
    let startX = 0;
    let startY = 0;
    let originX = 0;
    let originY = 0;

    scene.input.on('pointerdown', (p) => {
      // A drag that starts on the command panel scrolls nothing — otherwise
      // dialling a ship count would pan the galaxy out from under the panel.
      if (this.cb.blockPointer?.(p)) return;
      dragging = true;
      this.dragged = false;
      startX = p.x; startY = p.y;
      originX = this.root.x; originY = this.root.y;
    });
    scene.input.on('pointermove', (p) => {
      if (!dragging) return;
      const dx = p.x - startX;
      const dy = p.y - startY;
      // An 8px threshold so a slightly shaky click still selects a star.
      if (Math.abs(dx) > 8 || Math.abs(dy) > 8) this.dragged = true;
      if (!this.dragged) return;
      this.root.x = originX + dx;
      this.root.y = originY + dy;
      this.clampPan();
    });
    // Phaser emits the game objects' own pointerup handlers first and then this
    // one, with everything under the cursor in `objs` — so an empty list is a
    // genuine click on the void, which is how the panel gets dismissed.
    scene.input.on('pointerup', (p, objs) => {
      dragging = false;
      if (!this.dragged && (!objs || objs.length === 0) && !this.cb.blockPointer?.(p)) {
        this.cb.onEmptyClick?.(p);
      }
    });
    scene.input.on('wheel', (p, _objs, _dx, dy) => {
      if (this.cb.blockWheel?.(p) || this.cb.blockPointer?.(p)) return;
      this.applyZoom(this.zoomIndex + (dy > 0 ? -1 : 1), p.x, p.y);
    });
  }

  setViewer(idx) { this.viewerIdx = idx; this.rangeDirty = true; this.refresh(); }

  destroy() {
    this.tooltip.destroy();
    this.nebula?.destroy();
    this.bgLayer.destroy();
    this.starfield.destroy();
    this.root.destroy();
  }
}