import { Container, Graphics, Text } from 'pixi.js';
import { hazardColor, makeViewTransform } from './app.js';
import { playerClouds } from '../sim/clouds.js';
import { playerSystem } from '../sim/player.js';
import { otherEnd } from '../sim/galaxy.js';

export class GalaxyView {
  // onSelectSystem(systemId) -> UI intel panel
  constructor(renderer, world, { onSelectSystem, onJump }) {
    this.renderer = renderer;
    this.world = world;
    this.onSelectSystem = onSelectSystem;
    this.onJump = onJump;
    this.container = new Container();
    this.labelContainer = new Container();
    renderer.world.addChild(this.container);
    renderer.labels.addChild(this.labelContainer);

    this.staticG = new Graphics();
    this.cloudG = new Graphics();
    this.dynamicG = new Graphics();
    this.container.addChild(this.staticG, this.cloudG, this.dynamicG);
    this.hitNodes = new Container();
    this.container.addChild(this.hitNodes);
    this.buildStatic();
  }

  buildStatic() {
    const { galaxy } = this.world;
    const v = makeViewTransform(this.renderer.app);
    this.v = v;
    const g = this.staticG;
    g.clear();
    for (const lane of galaxy.lanes) {
      const a = galaxy.systems[lane.a], b = galaxy.systems[lane.b];
      g.moveTo(v.x(a.x), v.y(a.y)).lineTo(v.x(b.x), v.y(b.y))
        .stroke({ width: 2, color: hazardColor(lane.hazard), alpha: 0.55 });
    }
    for (const s of galaxy.systems) {
      g.circle(v.x(s.x), v.y(s.y), 7).fill({ color: 0xcfeeff });
    }
    this.labelContainer.removeChildren();
    this.hitNodes.removeChildren();
    for (const s of galaxy.systems) {
      const label = new Text({ text: s.name, style: { fill: '#7fa8c9', fontSize: 11, fontFamily: 'system-ui' } });
      label.position.set(v.x(s.x) + 10, v.y(s.y) - 6);
      this.labelContainer.addChild(label);

      const hit = new Graphics().circle(0, 0, 16).fill({ color: 0xffffff, alpha: 0.001 });
      hit.position.set(v.x(s.x), v.y(s.y));
      hit.eventMode = 'static';
      hit.cursor = 'pointer';
      hit.on('pointertap', () => this.handleSystemTap(s.id));
      this.hitNodes.addChild(hit);
    }
  }

  handleSystemTap(systemId) {
    this.onSelectSystem(systemId);
  }

  lanePoint(lane, fromSys, f) {
    const { galaxy } = this.world;
    const a = galaxy.systems[fromSys];
    const b = galaxy.systems[otherEnd(lane, fromSys)];
    return { x: this.v.x(a.x + (b.x - a.x) * f), y: this.v.y(a.y + (b.y - a.y) * f) };
  }

  update() {
    const sim = this.world;
    const v = this.v;
    const cur = playerSystem(sim);
    // Mid-lane the player observes nothing; don't exclude any visible band.
    const obsSys = sim.player.loc.kind === 'lane' ? null : cur;

    // Probability clouds: glowing strokes along lane segments, alpha ~ weight.
    const cg = this.cloudG;
    cg.clear();
    for (const cloud of playerClouds(sim, obsSys)) {
      for (const seg of cloud.segs) {
        const lane = sim.galaxy.lanes[seg.laneId];
        const p0 = this.lanePoint(lane, seg.fromSys, seg.f0);
        const p1 = this.lanePoint(lane, seg.fromSys, seg.f1);
        const alpha = Math.min(0.85, 0.18 + seg.w * 0.9);
        cg.moveTo(p0.x, p0.y).lineTo(p1.x, p1.y)
          .stroke({ width: 7, color: 0xffa94d, alpha });
      }
    }

    // Player marker: bright cyan triangle at current position.
    const dg = this.dynamicG;
    dg.clear();
    const pos = this.playerXY();
    if (pos) {
      dg.poly([pos.x, pos.y - 8, pos.x + 6, pos.y + 6, pos.x - 6, pos.y + 6]).fill({ color: 0x4dffd2 });
    }
    // Halo on the player's current system.
    if (cur != null) {
      const s = sim.galaxy.systems[cur];
      dg.circle(v.x(s.x), v.y(s.y), 12).stroke({ width: 2, color: 0x4dffd2, alpha: 0.8 });
    }
  }

  playerXY() {
    const sim = this.world;
    const loc = sim.player.loc;
    const v = this.v;
    if (loc.kind === 'lane') {
      const lane = sim.galaxy.lanes[loc.laneId];
      const f = Math.min(1, (sim.t - loc.departT) / (loc.arriveT - loc.departT));
      return this.lanePoint(lane, loc.fromSys, f);
    }
    const sysId = playerSystem(sim);
    if (sysId == null) return null;
    const s = sim.galaxy.systems[sysId];
    return { x: v.x(s.x), y: v.y(s.y) };
  }

  setVisible(on) {
    this.container.visible = on;
    this.labelContainer.visible = on;
  }
}