import React from 'react';
import type { Object3D } from 'three';
import {
  planetaryGearState,
} from '../../../animations/mechanics';
import type { MachineAnimationModule } from '../../../animations/types';
import {
  BoltCircle,
  MachinePart,
  Shaft,
  ToothedGear,
} from './primitives';
import {
  EngineeringBaseplate,
  PartLabels,
  getPartVisualProps,
} from './proceduralSceneHelpers';
import type {
  ProceduralMachineDefinition,
  ProceduralMachineModule,
  ProceduralMachineSceneProps,
} from './types';

const PLANET_COUNT = 3;
const ORBIT_RADIUS = 1.08;

const definition: ProceduralMachineDefinition = {
  id: 'planetary-gearbox',
  slug: 'planetary-gearbox',
  title: 'Planetary Gearbox',
  subtitle: 'Coaxial reduction with sun, planets, ring, and carrier',
  category: 'Gearboxes & Drives',
  difficulty: 'Intermediate',
  summary: 'A compact epicyclic gear train showing sun input, fixed ring gear, planet orbit, and reduced carrier output.',
  description:
    'Planetary gearboxes pack high reduction ratios into a coaxial assembly. In this demonstration the sun gear is the input, the ring gear is fixed to the housing, and the planet carrier becomes the reduced-speed output shaft.',
  keywords: ['gearbox', 'planetary', 'epicyclic', 'gear ratio', 'reduction'],
  complexity: 7,
  dateAdded: '2025-02-04',
  typicalRpm: 'Input 500–6,000 RPM',
  facts: [
    {
      label: 'Demo ratio',
      value: '4:1 reduction',
      detail: 'With 24 sun teeth and 72 ring teeth, the carrier speed is sun/(sun+ring) = 0.25× input.',
    },
    {
      label: 'Architecture',
      value: 'Coaxial input/output',
      detail: 'The input and output shafts share the same centerline, valuable for compact transmissions.',
    },
    {
      label: 'Load sharing',
      value: 'Three planets',
      detail: 'Multiple planets distribute tooth load and increase torque density.',
    },
    {
      label: 'Common uses',
      value: 'Automatics, robotics, turbines',
      detail: 'Epicyclic stages are common in automatic transmissions, wheel hubs, and servo reducers.',
    },
  ],
  parts: [
    {
      id: 'sun-gear',
      name: 'Sun gear',
      description: 'Central input gear meshing with every planet gear.',
      material: 'Case-hardened steel',
      labelPosition: [0, 0.2, 0.78],
      engineeringNote: 'The sun gear often carries high speed and moderate torque.',
    },
    {
      id: 'ring-gear',
      name: 'Ring gear',
      description: 'Internally toothed outer gear fixed in this reduction configuration.',
      material: 'Nitrided alloy steel',
      labelPosition: [-1.88, 1.12, 0.6],
      engineeringNote: 'Holding the ring stationary creates carrier speed reduction.',
      defaultOpacity: 0.74,
    },
    {
      id: 'planet-carrier',
      name: 'Planet carrier',
      description: 'Rotating frame that supports planet pins and provides the reduced output.',
      material: 'Forged steel carrier',
      labelPosition: [1.6, 1.08, 0.72],
    },
    {
      id: 'planet-gear-a',
      name: 'Planet gear A',
      description: 'One of three identical gears rolling between the sun and ring.',
      labelPosition: [1.28, 0.28, 0.72],
    },
    {
      id: 'planet-gear-b',
      name: 'Planet gear B',
      description: 'Second planet gear sharing torque with the other planets.',
      labelPosition: [-1.02, 1.18, 0.72],
    },
    {
      id: 'planet-gear-c',
      name: 'Planet gear C',
      description: 'Third planet gear completing the balanced carrier set.',
      labelPosition: [-0.9, -0.98, 0.72],
    },
    {
      id: 'input-shaft',
      name: 'Input shaft',
      description: 'Shaft connected to the sun gear.',
      material: 'Splined steel shaft',
      labelPosition: [0, -1.7, 0.58],
    },
    {
      id: 'output-shaft',
      name: 'Output shaft',
      description: 'Coaxial output connected to the planet carrier.',
      material: 'Splined steel shaft',
      labelPosition: [1.85, -0.82, 0.58],
    },
    {
      id: 'housing',
      name: 'Housing',
      description: 'Stationary case that holds the ring gear and bearings.',
      material: 'Cast aluminium',
      labelPosition: [-2.05, -1.12, 0.55],
      defaultOpacity: 0.36,
    },
  ],
  cameraPresets: [
    { id: 'iso', label: 'Isometric', position: [3.8, 2.8, 4.4], target: [0, 0, 0], fov: 40 },
    { id: 'front', label: 'Gear mesh', position: [0, 0, 5.4], target: [0, 0, 0], fov: 36 },
    { id: 'side', label: 'Coaxial shafts', position: [4.6, 1.2, 2.2], target: [0, 0, 0], fov: 42 },
  ],
  tour: {
    id: 'tour-planetary-gearbox',
    machineId: 'planetary-gearbox',
    title: 'See how an epicyclic reducer works',
    description: 'Follow torque from the sun gear through rolling planets to the slower carrier output.',
    steps: [
      {
        id: 'sun-input',
        title: 'Sun gear input',
        body: 'The central sun gear is driven directly by the input shaft.',
        durationSeconds: 4,
        partIds: ['sun-gear', 'input-shaft'],
        camera: { position: [0.6, 1.4, 4.6], target: [0, 0, 0], duration: 1.1 },
        rpm: 420,
      },
      {
        id: 'planet-load-sharing',
        title: 'Planets share tooth load',
        body: 'Three planets roll between the sun and the fixed ring, splitting transmitted torque.',
        durationSeconds: 5,
        partIds: ['planet-gear-a', 'planet-gear-b', 'planet-gear-c'],
        camera: { position: [2.9, 2.4, 4.1], target: [0, 0, 0], duration: 1.1 },
        rpm: 360,
      },
      {
        id: 'ring-fixed',
        title: 'Fixed ring creates reduction',
        body: 'Because the ring cannot rotate, the planet carrier orbits much slower than the sun input.',
        durationSeconds: 5,
        partIds: ['ring-gear', 'housing', 'planet-carrier'],
        camera: { position: [-3.2, 2.1, 3.9], target: [0, 0, 0], duration: 1.1 },
        rpm: 360,
      },
      {
        id: 'carrier-output',
        title: 'Carrier is the output',
        body: 'The carrier output turns at one quarter of the input speed in this tooth-count example.',
        durationSeconds: 4,
        partIds: ['planet-carrier', 'output-shaft'],
        camera: { position: [4.2, 1.3, 2.2], target: [0.2, 0, 0], duration: 1.1 },
        rpm: 420,
      },
    ],
  },
  relatedMachineIds: ['differential-gear', 'geneva-drive', 'ball-bearing'],
};

function partProps(
  partId: string,
  props: ProceduralMachineSceneProps,
  explodeDirection: [number, number, number] = [0, 0, 0],
) {
  return {
    partId,
    registerPart: props.registerPart,
    explodeDirection,
    explodedDistance: props.explodedDistance ?? 0,
    onSelectPart: props.onSelectPart,
    onHoverPart: props.onHoverPart,
    ...getPartVisualProps(partId, props),
  };
}

function setPlanetPose(object: Object3D | undefined, angle: number, spin: number): void {
  if (!object) return;
  object.position.set(Math.cos(angle) * ORBIT_RADIUS, Math.sin(angle) * ORBIT_RADIUS, 0);
  object.rotation.z = spin;
}

export const planetaryGearboxAnimation: MachineAnimationModule = {
  id: 'planetary-gearbox-fixed-ring',
  machineId: 'planetary-gearbox',
  label: 'Fixed-ring planetary reduction',
  version: '1.0.0',
  defaultRpm: 360,
  minRpm: 30,
  maxRpm: 1800,
  cycleRevolutions: 1,
  cycleSteps: 18,
  loop: true,
  supportsReverse: true,
  reducedMotionStrategy: 'slow',
  update(context) {
    const state = planetaryGearState(context.shaftAngle, 24, 72, 24);
    const sun = context.getPart('sun-gear');
    const carrier = context.getPart('planet-carrier');
    const input = context.getPart('input-shaft');
    const output = context.getPart('output-shaft');

    if (sun) sun.rotation.z = -state.sunAngle;
    if (carrier) carrier.rotation.z = -state.carrierAngle;
    if (input) input.rotation.z = -state.sunAngle;
    if (output) output.rotation.z = -state.carrierAngle;

    for (let index = 0; index < PLANET_COUNT; index += 1) {
      const baseAngle = (index / PLANET_COUNT) * Math.PI * 2;
      setPlanetPose(
        context.getPart(`planet-gear-${String.fromCharCode(97 + index)}`),
        baseAngle + state.planetOrbitAngle,
        state.planetSpinAngle - baseAngle,
      );
    }

    context.setPhaseLabel(`Fixed-ring reduction — carrier output ${state.outputRatio.toFixed(2)}× input speed`);
    context.clearHighlights();

    if (context.cycleProgress < 0.25) context.highlightParts(['sun-gear', 'input-shaft'], 0.75);
    else if (context.cycleProgress < 0.6) context.highlightParts(['planet-gear-a', 'planet-gear-b', 'planet-gear-c'], 0.75);
    else context.highlightParts(['planet-carrier', 'output-shaft'], 0.75);
  },
};

function PlanetGear({
  id,
  props,
  index,
}: {
  id: string;
  props: ProceduralMachineSceneProps;
  index: number;
}): JSX.Element {
  const angle = (index / PLANET_COUNT) * Math.PI * 2;
  return (
    <MachinePart
      {...partProps(id, props, [Math.cos(angle) * 0.42, Math.sin(angle) * 0.42, 0.16])}
      position={[Math.cos(angle) * ORBIT_RADIUS, Math.sin(angle) * ORBIT_RADIUS, 0]}
    >
      <ToothedGear radius={0.34} teeth={24} thickness={0.22} color="#8794a7" accentColor="#c8d1dc" />
    </MachinePart>
  );
}

export function PlanetaryGearboxScene(props: ProceduralMachineSceneProps): JSX.Element {
  return (
    <group>
      <EngineeringBaseplate width={4.9} depth={3.5} />

      <MachinePart {...partProps('housing', props, [-0.35, -0.2, -0.08])} opacity={props.partState?.housing?.opacity ?? 0.32}>
        <mesh position={[0, 0, -0.16]} receiveShadow>
          <torusGeometry args={[1.82, 0.16, 24, 128]} />
          <meshStandardMaterial color="#223044" transparent opacity={0.34} metalness={0.32} roughness={0.52} />
        </mesh>
      </MachinePart>

      <MachinePart {...partProps('ring-gear', props, [-0.32, 0.14, 0.08])}>
        <mesh>
          <torusGeometry args={[1.55, 0.13, 24, 128]} />
          <meshStandardMaterial color="#516173" metalness={0.76} roughness={0.3} />
        </mesh>
        {Array.from({ length: 72 }, (_, index) => {
          const angle = (index / 72) * Math.PI * 2;
          return (
            <mesh key={index} position={[Math.cos(angle) * 1.38, Math.sin(angle) * 1.38, 0]} rotation={[0, 0, angle]}>
              <boxGeometry args={[0.09, 0.035, 0.2]} />
              <meshStandardMaterial color="#9aa7b8" metalness={0.78} roughness={0.28} />
            </mesh>
          );
        })}
      </MachinePart>

      <MachinePart {...partProps('sun-gear', props, [0, 0, 0.22])}>
        <ToothedGear radius={0.38} teeth={24} thickness={0.28} color="#ffb04c" accentColor="#ffd08b" />
      </MachinePart>

      <PlanetGear id="planet-gear-a" props={props} index={0} />
      <PlanetGear id="planet-gear-b" props={props} index={1} />
      <PlanetGear id="planet-gear-c" props={props} index={2} />

      <MachinePart {...partProps('planet-carrier', props, [0.28, 0.18, 0.24])}>
        <mesh position={[0, 0, 0.18]}>
          <torusGeometry args={[ORBIT_RADIUS, 0.035, 12, 96]} />
          <meshStandardMaterial color="#4c8dff" metalness={0.74} roughness={0.28} />
        </mesh>
        <BoltCircle radius={ORBIT_RADIUS} count={3} boltRadius={0.07} color="#88b3ff" />
        {Array.from({ length: PLANET_COUNT }, (_, index) => {
          const angle = (index / PLANET_COUNT) * Math.PI * 2;
          return (
            <mesh key={index} position={[Math.cos(angle) * ORBIT_RADIUS * 0.52, Math.sin(angle) * ORBIT_RADIUS * 0.52, 0.18]} rotation={[0, 0, angle]}>
              <boxGeometry args={[ORBIT_RADIUS, 0.035, 0.045]} />
              <meshStandardMaterial color="#4c8dff" metalness={0.74} roughness={0.28} />
            </mesh>
          );
        })}
      </MachinePart>

      <MachinePart {...partProps('input-shaft', props, [0, -0.42, 0.12])} position={[0, 0, -0.62]}>
        <Shaft length={1.2} radius={0.095} axis="z" color="#d0d6df" />
      </MachinePart>

      <MachinePart {...partProps('output-shaft', props, [0.48, -0.22, 0.18])} position={[0, 0, 0.72]}>
        <Shaft length={1.35} radius={0.12} axis="z" color="#8bb4ff" />
      </MachinePart>

      <PartLabels parts={definition.parts} visible={props.labelsVisible} />
    </group>
  );
}

export const planetaryGearbox: ProceduralMachineModule = {
  definition,
  animationModule: planetaryGearboxAnimation,
  Scene: PlanetaryGearboxScene,
};