import * as THREE from 'three';
import { FlightModel } from './flight-model.js';
import { Terrain } from './terrain.js';
import { Airport } from './airport.js';
import { Aircraft } from './aircraft.js';
import { HUD } from './hud.js';
import { UI } from './ui.js';
import { RetroEffect } from './retro.js';
import { Sound } from './sound.js';

const GW = 320;
const GH = 200;

class Game {
  constructor() {
    this.state = 'LOADING';
    this.clock = new THREE.Clock();
    this.cockpitView = false;
    this.fixedDelta = 1 / 60;
    this.accumulator = 0;

    this.initRenderer();
    this.initScene();
    this.initCamera();
    this.initInput();
    this.initComponents();
    this.initUI();

    // Start loading sequence
    this.startLoading();

    // Begin render loop
    this.animate();
  }

  initRenderer() {
    this.renderer = new THREE.WebGLRenderer({
      canvas: document.getElementById('game-canvas'),
      antialias: false,
      powerPreference: 'low-power',
    });
    this.renderer.setSize(GW, GH, false);
    this.renderer.setPixelRatio(1);
  }

  initScene() {
    this.scene = new THREE.Scene();
    this.scene.background = new THREE.Color(0x4466AA);
    this.scene.fog = new THREE.Fog(0x4466AA, 600, 2000);

    // Hemisphere light (sky/ground)
    const hemi = new THREE.HemisphereLight(0x8888CC, 0x444422, 0.6);
    this.scene.add(hemi);

    // Directional light (sun)
    const sun = new THREE.DirectionalLight(0xFFFFDD, 1.2);
    sun.position.set(200, 120, 100);
    this.scene.add(sun);

    // Ambient
    this.scene.add(new THREE.AmbientLight(0x404050, 0.3));

    // Low-poly clouds
    this.buildClouds();
  }

  buildClouds() {
    const cloudMat = new THREE.MeshLambertMaterial({
      color: 0xDDDDDD,
      flatShading: true,
      transparent: true,
      opacity: 0.85,
    });
    const cloudPositions = [
      { x: 300, z: 200, y: 180 },
      { x: -400, z: -100, y: 220 },
      { x: 500, z: -300, y: 160 },
      { x: -200, z: 400, y: 200 },
      { x: 100, z: -500, y: 190 },
      { x: -600, z: 300, y: 170 },
      { x: 400, z: 500, y: 210 },
      { x: -300, z: -400, y: 185 },
      { x: 700, z: 100, y: 195 },
      { x: -500, z: -200, y: 175 },
    ];

    cloudPositions.forEach(({ x, y, z }) => {
      const cloud = new THREE.Group();
      const numPuffs = 3 + Math.floor(Math.random() * 4);
      for (let i = 0; i < numPuffs; i++) {
        const size = 10 + Math.random() * 20;
        const puff = new THREE.Mesh(
          new THREE.SphereGeometry(size, 5, 4),
          cloudMat
        );
        puff.position.set(
          (Math.random() - 0.5) * 30,
          (Math.random() - 0.5) * 5,
          (Math.random() - 0.5) * 20
        );
        puff.scale.y = 0.4;
        cloud.add(puff);
      }
      cloud.position.set(x, y, z);
      this.scene.add(cloud);
    });
  }

  initCamera() {
    this.camera = new THREE.PerspectiveCamera(75, GW / GH, 0.5, 3000);
    this.camera.position.set(0, 15, 20);
  }

  initInput() {
    this.keys = {};
    window.addEventListener('keydown', (e) => {
      this.keys[e.code] = true;
      this.handleKeydown(e.code);
    });
    window.addEventListener('keyup', (e) => {
      this.keys[e.code] = false;
    });
  }

  initComponents() {
    this.terrain = new Terrain(2000, 100);
    this.airport = new Airport();
    this.aircraft = new Aircraft();
    this.flightModel = new FlightModel();
    this.hud = new HUD();
    this.retro = new RetroEffect(this.renderer, GW, GH);
    this.sound = new Sound();
  }

  initUI() {
    this.ui = new UI();
    this.ui.onNewFlight = () => this.startFlight();
    this.ui.onResume = () => this.resumeFlight();
    this.ui.onMainMenu = () => this.returnToMenu();
    this.ui.onQuit = () => this.quitGame();
  }

  handleKeydown(code) {
    // Init audio on first keypress
    this.sound.init();

    if (this.ui.menuActive) {
      if (this.ui.handleMenuInput(code)) return;
    }

    if (this.ui.controlsActive) {
      if (this.ui.handleControlsInput()) return;
    }

    if (this.ui.pauseMenu.style.display !== 'none') {
      if (this.ui.handlePauseInput(code)) return;
    }

    if (this.state === 'FLYING' && code === 'Escape') {
      this.pauseFlight();
      this.sound.beep(400, 60);
    }

    if (this.state === 'FLYING' && code === 'KeyC') {
      this.cockpitView = !this.cockpitView;
    }
  }

  getFlightInput() {
    return {
      throttleUp: !!this.keys['KeyW'],
      throttleDown: !!this.keys['KeyS'],
      pitch: this.keys['ArrowUp'] ? 1 : this.keys['ArrowDown'] ? -1 : 0,
      roll: this.keys['ArrowLeft'] ? 1 : this.keys['ArrowRight'] ? -1 : 0,
      yaw: this.keys['KeyQ'] ? -1 : this.keys['KeyE'] ? 1 : 0,
    };
  }

  async startLoading() {
    await this.ui.showLoading(async (step) => {
      if (step === 0) {
        // Generate terrain
        const terrainMesh = this.terrain.createMesh();
        this.scene.add(terrainMesh);
        const water = this.terrain.createWater();
        this.scene.add(water);
      } else if (step === 1) {
        // Build airport
        this.airport.build();
        this.scene.add(this.airport.getGroup());
      } else if (step === 2) {
        // Place aircraft
        const aircraftGroup = this.aircraft.getGroup();
        // Position on runway
        const terrainH = this.terrain.getHeightAt(0, 50);
        this.flightModel.position.set(0, terrainH + 2, 50);
        this.flightModel.orientation.y = Math.PI; // Face down runway (south)
        aircraftGroup.position.copy(this.flightModel.position);
        aircraftGroup.rotation.copy(this.flightModel.orientation);
        this.scene.add(aircraftGroup);
      }
    });
    this.state = 'MENU';
  }

  startFlight() {
    this.ui.hideMainMenu();
    this.state = 'FLYING';
    this.hud.show();
    this.sound.takeoffSound();
  }

  pauseFlight() {
    this.state = 'PAUSED';
    this.ui.showPauseMenu();
  }

  resumeFlight() {
    this.state = 'FLYING';
    this.ui.hidePauseMenu();
  }

  returnToMenu() {
    this.state = 'MENU';
    this.ui.hidePauseMenu();
    this.ui.showMainMenu();
    this.hud.hide();
  }

  quitGame() {
    this.state = 'QUIT';
    this.ui.showQuitScreen();
    this.hud.hide();
  }

  updateCamera() {
    const acPos = this.flightModel.position;
    const acRot = this.flightModel.orientation;

    if (this.cockpitView) {
      const forward = new THREE.Vector3(0, 0, -1).applyEuler(acRot);
      const up = new THREE.Vector3(0, 1, 0).applyEuler(acRot);
      this.camera.position.copy(acPos)
        .add(forward.clone().multiplyScalar(3))
        .add(up.clone().multiplyScalar(1.5));
      this.camera.lookAt(acPos.clone().add(forward.clone().multiplyScalar(20)));
    } else {
      // Chase camera
      const forward = new THREE.Vector3(0, 0, -1).applyEuler(acRot);
      const up = new THREE.Vector3(0, 1, 0).applyEuler(acRot);
      const desiredPos = acPos.clone()
        .add(forward.multiplyScalar(-20))
        .add(up.multiplyScalar(10));

      this.camera.position.lerp(desiredPos, 0.06);

      const lookTarget = acPos.clone().add(up.multiplyScalar(2));
      this.camera.lookAt(lookTarget);
    }
  }

  animate() {
    requestAnimationFrame(() => this.animate());

    const deltaRaw = this.clock.getDelta();
    const delta = Math.min(deltaRaw, 0.1);
    const elapsed = this.clock.getElapsedTime();

    if (this.state === 'FLYING') {
      this.accumulator += delta;
      while (this.accumulator >= this.fixedDelta) {
        const input = this.getFlightInput();
        this.flightModel.update(
          this.fixedDelta,
          input,
          (x, z) => this.terrain.getHeightAt(x, z)
        );

        // Sync aircraft mesh
        const acGroup = this.aircraft.getGroup();
        acGroup.position.copy(this.flightModel.position);
        acGroup.rotation.copy(this.flightModel.orientation);

        // Propeller
        this.aircraft.updatePropeller(this.flightModel.thrust, this.fixedDelta);

        // Landing gear
        this.aircraft.retractGear(this.flightModel.onGround);

        this.accumulator -= this.fixedDelta;
      }

      this.updateCamera();
      this.hud.draw(this.flightModel);
      this.sound.update(this.flightModel.thrust);
    }

    // Update retro effect
    this.retro.update(elapsed);

    // Render with retro post-processing
    this.retro.render(this.scene, this.camera);
  }
}

new Game();