import { Group, MeshStandardMaterial } from 'three';

import type { LoadedMachineAsset, MachineMetadata, ViewerPart } from '../../types/viewer';
import {
  createBoxPartMesh,
  createCylinderBetween,
  createCylinderPartMesh,
  createPartGroup,
  createPbrMaterial,
  createPhysicalGlassMaterial,
  createSpherePartMesh,
  createTorusPartMesh,
  disposeObjectTree
} from './geometry';

const PARTS: ViewerPart[] = [
  {
    id: 'engine-block',
    name: 'Engine Block',
    description:
      'The cast block carries the cylinder bore, coolant jacket, crankcase loads, and the bolted interfaces for the head and oil sump.',
    material: 'Cast iron alloy',
    explodeDirection: [-0.55, 0.05, -0.35],
    annotationPosition: [-1.2, 1.15, 0.86],
    specs: {
      'Primary load': 'Combustion pressure and crank bearing reaction',
      'Typical material': 'Cast iron or aluminium alloy',
      'Design note': 'Cutaway side exposes the liner and piston travel'
    }
  },
  {
    id: 'cylinder-head',
    name: 'Cylinder Head',
    description:
      'The head seals the combustion chamber and houses the poppet valves, ports, spark plug, and cam-bearing structure.',
    material: 'Aluminium alloy',
    explodeDirection: [0, 0.78, 0],
    annotationPosition: [0.7, 2.72, 0.74],
    specs: {
      'Thermal role': 'Transfers combustion heat into coolant passages',
      'Valve layout': 'Single intake and exhaust pair in this teaching model'
    }
  },
  {
    id: 'piston',
    name: 'Piston',
    description:
      'The piston converts expanding combustion gas pressure into linear force while the rings seal the cylinder wall.',
    material: 'Forged aluminium',
    explodeDirection: [0.22, 0.42, 0.16],
    annotationPosition: [0.38, 1.55, 0.2],
    specs: {
      Motion: 'Reciprocating',
      'Ring pack': 'Compression and oil-control rings',
      'Peak acceleration': 'Thousands of g in high-speed engines'
    }
  },
  {
    id: 'connecting-rod',
    name: 'Connecting Rod',
    description:
      'The connecting rod transmits piston force to the crank throw while accommodating angularity through wrist-pin and big-end bearings.',
    material: 'Forged steel',
    explodeDirection: [0.52, 0.18, 0],
    annotationPosition: [0.58, 0.77, 0.08],
    specs: {
      Loading: 'Alternating tension and compression',
      'Critical region': 'Big-end cap and bolt stretch'
    }
  },
  {
    id: 'crankshaft',
    name: 'Crankshaft',
    description:
      'The crankshaft offsets the crank pin from the main journals, converting reciprocating rod force into smooth rotary output.',
    material: 'Nitrided steel',
    explodeDirection: [0, -0.25, 0.64],
    annotationPosition: [0.1, 0.05, 0.78],
    specs: {
      Motion: 'Continuous rotation',
      'Balance feature': 'Counterweights reduce shaking force',
      'Bearing type': 'Plain hydrodynamic journals'
    }
  },
  {
    id: 'camshaft',
    name: 'Camshaft',
    description:
      'Eccentric cam lobes drive the valve train at half crankshaft speed in a four-stroke cycle.',
    material: 'Chilled cast iron',
    explodeDirection: [-0.35, 0.46, -0.35],
    annotationPosition: [-0.72, 2.52, -0.68],
    specs: {
      'Speed ratio': '0.5 × crankshaft RPM',
      Function: 'Valve lift timing and duration'
    }
  },
  {
    id: 'intake-valve',
    name: 'Intake Valve',
    description:
      'The intake valve opens during the intake stroke to admit fresh air-fuel mixture from the intake port into the cylinder.',
    material: 'Stainless valve steel',
    explodeDirection: [-0.45, 0.25, 0.42],
    annotationPosition: [-0.45, 2.2, 0.42],
    specs: {
      Event: 'Opens before top dead centre, closes after bottom dead centre',
      Cooling: 'Cooled by incoming charge and seat contact'
    }
  },
  {
    id: 'exhaust-valve',
    name: 'Exhaust Valve',
    description:
      'The exhaust valve opens near the end of the power stroke so burned gas can exit through the exhaust port.',
    material: 'High-temperature valve steel',
    explodeDirection: [0.45, 0.25, 0.42],
    annotationPosition: [0.48, 2.17, 0.42],
    specs: {
      Event: 'Opens before bottom dead centre on power stroke',
      'Temperature exposure': 'Often above 700 °C at the valve head'
    }
  },
  {
    id: 'spark-plug',
    name: 'Spark Plug',
    description:
      'The spark plug initiates combustion with a timed electrical discharge across the electrode gap.',
    material: 'Ceramic insulator and nickel alloy electrode',
    explodeDirection: [0, 0.78, 0.18],
    annotationPosition: [0, 3.05, 0.18],
    specs: {
      Timing: 'Advanced before top dead centre',
      'Gap range': 'Typically 0.6–1.1 mm'
    }
  },
  {
    id: 'intake-manifold',
    name: 'Intake Manifold',
    description:
      'The intake manifold guides the air-fuel charge toward the intake port with low pressure loss and controlled runner volume.',
    material: 'Cast aluminium',
    explodeDirection: [-0.85, 0.2, 0.12],
    annotationPosition: [-1.55, 2.13, 0.06],
    specs: {
      Purpose: 'Distributes charge to cylinders',
      'Design trade-off': 'Runner length tunes torque band'
    }
  },
  {
    id: 'exhaust-manifold',
    name: 'Exhaust Manifold',
    description:
      'The exhaust manifold collects hot exhaust gas and routes it away from the cylinder head.',
    material: 'Cast iron / stainless steel',
    explodeDirection: [0.85, 0.16, 0.1],
    annotationPosition: [1.55, 2.03, 0.04],
    specs: {
      Purpose: 'Collects high-temperature exhaust pulses',
      'Design trade-off': 'Flow loss versus packaging and durability'
    }
  },
  {
    id: 'flywheel',
    name: 'Flywheel',
    description:
      'The flywheel stores rotational kinetic energy, smoothing torque pulses between combustion events.',
    material: 'Steel',
    explodeDirection: [0.9, -0.1, 0],
    annotationPosition: [1.92, 0.18, 0],
    specs: {
      Function: 'Inertia storage and clutch interface',
      Effect: 'Reduces cyclic speed variation'
    }
  },
  {
    id: 'timing-chain',
    name: 'Timing Chain',
    description:
      'The timing chain synchronizes the camshaft with the crankshaft so the valves open at the correct crank angles.',
    material: 'Hardened steel links',
    explodeDirection: [-0.82, 0.05, -0.4],
    annotationPosition: [-1.58, 1.35, -0.62],
    specs: {
      Ratio: '2:1 crank-to-cam',
      Requirement: 'Maintains phase accuracy under load and heat'
    }
  }
];

export const FOUR_STROKE_ENGINE_METADATA: MachineMetadata = {
  id: 'four-stroke-petrol-engine',
  slug: 'four-stroke-petrol-engine',
  title: 'Four Stroke Petrol Engine',
  subtitle: 'Cutaway single-cylinder teaching model',
  category: 'Engines',
  difficulty: 'Beginner',
  description:
    'A premium interactive cutaway of a spark-ignition four-stroke engine, exposing the intake, compression, combustion, and exhaust mechanisms through selectable engineered components.',
  keywords: ['engine', 'petrol', 'gasoline', 'piston', 'crankshaft', 'valves', 'four stroke'],
  facts: [
    {
      label: 'Cycle',
      value: '720° crank rotation',
      detail: 'A complete intake-compression-power-exhaust cycle requires two crankshaft revolutions.'
    },
    {
      label: 'Typical RPM',
      value: '800–6,500 rpm',
      detail: 'Passenger-car spark ignition engines idle below 1,000 rpm and commonly operate below 6,500 rpm.'
    },
    {
      label: 'Invented',
      value: '1876',
      detail: 'Nikolaus Otto demonstrated the practical four-stroke internal combustion engine.'
    },
    {
      label: 'Applications',
      value: 'Cars, motorcycles, generators',
      detail: 'The architecture is common wherever compact power density and throttle response matter.'
    }
  ],
  parts: PARTS,
  relatedMachineIds: ['two-stroke-engine', 'diesel-engine', 'v8-engine', 'turbocharger'],
  approximateBounds: {
    center: [0, 1.15, 0],
    radius: 3.6,
    min: [-2.1, -0.65, -1.25],
    max: [2.25, 3.25, 1.25]
  }
};

export function createFourStrokeEngineAsset(): LoadedMachineAsset {
  const root = new Group();
  root.name = 'FourStrokePetrolEngine_ProceduralCutaway';
  root.userData.assetKind = 'procedural';
  root.userData.machineId = FOUR_STROKE_ENGINE_METADATA.id;

  const castIron = createPbrMaterial('castIron');
  const aluminium = createPbrMaterial('aluminium');
  const brushedSteel = createPbrMaterial('brushedSteel');
  const polishedSteel = createPbrMaterial('polishedSteel');
  const darkSteel = createPbrMaterial('darkSteel');
  const brass = createPbrMaterial('brass');
  const rubber = createPbrMaterial('rubber');
  const ceramic = createPbrMaterial('ceramic');
  const copper = createPbrMaterial('copper');
  const warm = createPbrMaterial('warmHighlight');
  const intakeBlue = createPbrMaterial('fluidBlue');
  const exhaustOrange = createPbrMaterial('exhaustOrange');
  const glass = createPhysicalGlassMaterial('#8fd4ff', 0.22);
  const black = createPbrMaterial('matteBlack');

  addEngineBlock(root, castIron, glass);
  addCylinderHead(root, aluminium, darkSteel);
  addPiston(root, aluminium, darkSteel);
  addConnectingRod(root, polishedSteel, brass);
  addCrankshaft(root, brushedSteel, darkSteel);
  addCamshaft(root, darkSteel, polishedSteel);
  addValve(root, 'intake-valve', polishedSteel, intakeBlue, -0.38);
  addValve(root, 'exhaust-valve', polishedSteel, exhaustOrange, 0.38);
  addSparkPlug(root, ceramic, polishedSteel, copper);
  addIntakeManifold(root, aluminium, intakeBlue);
  addExhaustManifold(root, darkSteel, exhaustOrange);
  addFlywheel(root, brushedSteel, black);
  addTimingChain(root, brushedSteel, warm);

  root.traverse((object) => {
    object.frustumCulled = true;
  });

  return {
    root,
    metadata: FOUR_STROKE_ENGINE_METADATA,
    parts: PARTS,
    source: {
      kind: 'procedural',
      generatedAt: new Date(0).toISOString()
    },
    dispose: () => disposeObjectTree(root)
  };
}

function getPart(id: string): ViewerPart {
  const part = PARTS.find((entry) => entry.id === id);
  if (!part) {
    throw new Error(`Unknown four-stroke engine part: ${id}`);
  }

  return part;
}

function addEngineBlock(root: Group, castIron: MeshStandardMaterial, glass: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('engine-block'));

  createBoxPartMesh(group, 'Cutaway crankcase casting', [1.72, 1.85, 1.28], castIron, {
    position: [0, 0.88, 0]
  });
  createBoxPartMesh(group, 'Open cylinder wall section', [1.08, 1.58, 0.16], glass, {
    position: [0, 1.34, 0.62]
  });
  createCylinderPartMesh(group, 'Cylinder liner', 0.46, 0.46, 1.68, glass, {
    position: [0, 1.42, 0],
    radialSegments: 72
  });
  createBoxPartMesh(group, 'Oil sump flange', [1.94, 0.32, 1.42], castIron, {
    position: [0, -0.18, 0]
  });
  createBoxPartMesh(group, 'Main bearing bridge', [0.42, 0.34, 1.42], castIron, {
    position: [-0.52, 0.2, 0]
  });
  createBoxPartMesh(group, 'Main bearing bridge rear', [0.42, 0.34, 1.42], castIron, {
    position: [0.52, 0.2, 0]
  });

  root.add(group);
}

function addCylinderHead(root: Group, aluminium: MeshStandardMaterial, darkSteel: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('cylinder-head'));

  createBoxPartMesh(group, 'Combustion chamber roof', [1.82, 0.58, 1.2], aluminium, {
    position: [0, 2.12, 0]
  });
  createBoxPartMesh(group, 'Valve cover', [1.62, 0.34, 1.0], darkSteel, {
    position: [0, 2.62, 0]
  });
  createCylinderPartMesh(group, 'Left cam bearing cap', 0.14, 0.14, 1.55, aluminium, {
    position: [-0.56, 2.6, -0.35],
    rotation: [Math.PI / 2, 0, 0],
    radialSegments: 32
  });
  createCylinderPartMesh(group, 'Right cam bearing cap', 0.14, 0.14, 1.55, aluminium, {
    position: [0.56, 2.6, -0.35],
    rotation: [Math.PI / 2, 0, 0],
    radialSegments: 32
  });
  createBoxPartMesh(group, 'Head gasket plane', [1.9, 0.055, 1.22], darkSteel, {
    position: [0, 1.78, 0]
  });

  root.add(group);
}

function addPiston(root: Group, aluminium: MeshStandardMaterial, darkSteel: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('piston'));

  createCylinderPartMesh(group, 'Piston crown', 0.42, 0.42, 0.38, aluminium, {
    position: [0, 1.38, 0],
    radialSegments: 72
  });
  createCylinderPartMesh(group, 'Compression ring upper', 0.425, 0.425, 0.025, darkSteel, {
    position: [0, 1.55, 0],
    radialSegments: 72
  });
  createCylinderPartMesh(group, 'Compression ring lower', 0.425, 0.425, 0.025, darkSteel, {
    position: [0, 1.43, 0],
    radialSegments: 72
  });
  createCylinderPartMesh(group, 'Wrist pin', 0.075, 0.075, 0.98, darkSteel, {
    position: [0, 1.24, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 32
  });

  root.add(group);
}

function addConnectingRod(root: Group, steel: MeshStandardMaterial, brass: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('connecting-rod'));

  createCylinderBetween(group, 'Rod beam', [0, 1.18, 0], [0.22, 0.36, 0], 0.075, steel, 32);
  createCylinderPartMesh(group, 'Small-end bushing', 0.17, 0.17, 0.16, brass, {
    position: [0, 1.18, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 40
  });
  createCylinderPartMesh(group, 'Big-end bearing', 0.25, 0.25, 0.2, brass, {
    position: [0.22, 0.36, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createBoxPartMesh(group, 'Big-end cap split line', [0.48, 0.035, 0.22], steel, {
    position: [0.22, 0.2, 0]
  });

  root.add(group);
}

function addCrankshaft(root: Group, steel: MeshStandardMaterial, darkSteel: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('crankshaft'));

  createCylinderPartMesh(group, 'Main crank journal', 0.13, 0.13, 2.38, steel, {
    position: [0, 0.18, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createCylinderPartMesh(group, 'Offset crank pin', 0.12, 0.12, 0.62, steel, {
    position: [0.22, 0.36, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createBoxPartMesh(group, 'Forward crank web', [0.16, 0.52, 0.36], darkSteel, {
    position: [-0.18, 0.27, 0]
  });
  createBoxPartMesh(group, 'Rear crank web', [0.16, 0.52, 0.36], darkSteel, {
    position: [0.62, 0.27, 0]
  });
  createCylinderPartMesh(group, 'Counterweight left', 0.36, 0.28, 0.15, darkSteel, {
    position: [-0.72, 0.1, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createCylinderPartMesh(group, 'Counterweight right', 0.36, 0.28, 0.15, darkSteel, {
    position: [0.94, 0.1, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });

  root.add(group);
}

function addCamshaft(root: Group, darkSteel: MeshStandardMaterial, polished: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('camshaft'));

  createCylinderPartMesh(group, 'Camshaft core', 0.095, 0.095, 1.64, darkSteel, {
    position: [0, 2.55, -0.38],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 40
  });
  createCylinderPartMesh(group, 'Intake cam lobe', 0.19, 0.11, 0.18, polished, {
    position: [-0.35, 2.55, -0.38],
    rotation: [0.35, 0, Math.PI / 2],
    radialSegments: 36
  });
  createCylinderPartMesh(group, 'Exhaust cam lobe', 0.19, 0.11, 0.18, polished, {
    position: [0.35, 2.55, -0.38],
    rotation: [-0.35, 0, Math.PI / 2],
    radialSegments: 36
  });
  createCylinderPartMesh(group, 'Cam sprocket', 0.38, 0.38, 0.1, darkSteel, {
    position: [-0.92, 2.55, -0.38],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });

  root.add(group);
}

function addValve(
  root: Group,
  partId: 'intake-valve' | 'exhaust-valve',
  steel: MeshStandardMaterial,
  flowMaterial: MeshStandardMaterial,
  x: number
): void {
  const group = createPartGroup(getPart(partId));

  createCylinderPartMesh(group, `${partId} stem`, 0.035, 0.035, 0.78, steel, {
    position: [x, 2.12, 0.18],
    rotation: [0.18 * Math.sign(x), 0, 0],
    radialSegments: 24
  });
  createCylinderPartMesh(group, `${partId} valve head`, 0.18, 0.12, 0.1, steel, {
    position: [x, 1.73, 0.23],
    rotation: [Math.PI, 0, 0],
    radialSegments: 36
  });
  createSpherePartMesh(group, `${partId} port gas highlight`, 0.13, flowMaterial, {
    position: [x * 1.22, 1.93, 0.52],
    scale: [1.6, 0.55, 0.55]
  });

  root.add(group);
}

function addSparkPlug(
  root: Group,
  ceramic: MeshStandardMaterial,
  steel: MeshStandardMaterial,
  copper: MeshStandardMaterial
): void {
  const group = createPartGroup(getPart('spark-plug'));

  createCylinderPartMesh(group, 'Ceramic insulator', 0.075, 0.095, 0.58, ceramic, {
    position: [0, 2.78, 0.12],
    rotation: [0.18, 0, 0],
    radialSegments: 32
  });
  createCylinderPartMesh(group, 'Threaded shell', 0.09, 0.09, 0.18, steel, {
    position: [0, 2.48, 0.18],
    rotation: [0.18, 0, 0],
    radialSegments: 32
  });
  createCylinderPartMesh(group, 'Central electrode', 0.022, 0.022, 0.26, copper, {
    position: [0, 2.34, 0.22],
    rotation: [0.18, 0, 0],
    radialSegments: 16
  });

  root.add(group);
}

function addIntakeManifold(
  root: Group,
  aluminium: MeshStandardMaterial,
  flowMaterial: MeshStandardMaterial
): void {
  const group = createPartGroup(getPart('intake-manifold'));

  createCylinderPartMesh(group, 'Intake runner', 0.18, 0.24, 1.36, aluminium, {
    position: [-1.06, 2.08, 0.08],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 40
  });
  createCylinderPartMesh(group, 'Throttle body', 0.29, 0.29, 0.32, aluminium, {
    position: [-1.82, 2.08, 0.08],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createSpherePartMesh(group, 'Intake charge plume', 0.18, flowMaterial, {
    position: [-0.72, 2.02, 0.28],
    scale: [1.9, 0.5, 0.5]
  });

  root.add(group);
}

function addExhaustManifold(
  root: Group,
  steel: MeshStandardMaterial,
  flowMaterial: MeshStandardMaterial
): void {
  const group = createPartGroup(getPart('exhaust-manifold'));

  createCylinderPartMesh(group, 'Exhaust runner', 0.19, 0.26, 1.42, steel, {
    position: [1.08, 1.96, 0.08],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 40
  });
  createCylinderPartMesh(group, 'Collector outlet', 0.3, 0.3, 0.38, steel, {
    position: [1.88, 1.96, 0.08],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createSpherePartMesh(group, 'Exhaust pulse glow', 0.2, flowMaterial, {
    position: [0.76, 1.91, 0.28],
    scale: [1.8, 0.48, 0.48]
  });

  root.add(group);
}

function addFlywheel(root: Group, steel: MeshStandardMaterial, black: MeshStandardMaterial): void {
  const group = createPartGroup(getPart('flywheel'));

  createCylinderPartMesh(group, 'Flywheel rim', 0.72, 0.72, 0.2, steel, {
    position: [1.48, 0.18, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 72
  });
  createCylinderPartMesh(group, 'Flywheel hub', 0.24, 0.24, 0.27, black, {
    position: [1.48, 0.18, 0],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createTorusPartMesh(group, 'Ring gear teeth band', 0.73, 0.028, black, {
    position: [1.48, 0.18, 0],
    rotation: [0, Math.PI / 2, 0],
    radialSegments: 20,
    tubularSegments: 96
  });

  root.add(group);
}

function addTimingChain(
  root: Group,
  steel: MeshStandardMaterial,
  highlight: MeshStandardMaterial
): void {
  const group = createPartGroup(getPart('timing-chain'));

  createTorusPartMesh(group, 'Timing chain loop upper', 0.55, 0.035, steel, {
    position: [-1.03, 1.42, -0.48],
    rotation: [Math.PI / 2, 0, 0],
    scale: [0.58, 1.62, 1]
  });
  createCylinderPartMesh(group, 'Crank sprocket', 0.28, 0.28, 0.1, steel, {
    position: [-0.95, 0.18, -0.48],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 48
  });
  createCylinderPartMesh(group, 'Highlighted timing mark', 0.055, 0.055, 0.08, highlight, {
    position: [-0.95, 0.44, -0.48],
    rotation: [0, 0, Math.PI / 2],
    radialSegments: 18
  });

  root.add(group);
}