epam/miew

import selectors from './selectors'
import { Box3, Sphere, Vector3 } from 'three'

/**
 * Basic biological unit class.
 *
 * @exports BiologicalUnit
 * @constructor
 */
class BiologicalUnit {
  constructor(complex) {
    this._complex = complex
    this._selector = selectors.keyword('All')()
    this._boundaries = {
      boundingBox: new Box3(),
      boundingSphere: new Sphere()
    }
  }

  computeBoundaries() {
    const atoms = this._complex._atoms
    const n = atoms.length
    const selector = this._selector

    const { boundingBox } = this._boundaries
    boundingBox.makeEmpty()
    if (n === 1) {
      boundingBox.expandByPoint(atoms[0].position)
      const bbc = new Vector3()
      boundingBox.getCenter(bbc)
      const s = 2 * atoms[0].element.radius
      boundingBox.setFromCenterAndSize(bbc, new Vector3(s, s, s))
    } else {
      for (let i = 0; i < n; ++i) {
        if (selector.includesAtom(atoms[i])) {
          boundingBox.expandByPoint(atoms[i].position)
        }
      }
    }

    // Build bounding sphere
    let radiusSquared = 0.0
    const center = new Vector3()
    boundingBox.getCenter(center)
    if (n === 1) {
      this._boundaries.boundingSphere.set(center, atoms[0].element.radius)
    } else {
      for (let i = 0; i < n; ++i) {
        if (!selector.includesAtom(atoms[i])) {
          continue
        }
        const pos = atoms[i].position
        const lengthSquared = center.distanceToSquared(pos)
        if (radiusSquared < lengthSquared) {
          radiusSquared = lengthSquared
        }
      }
      this._boundaries.boundingSphere.set(center, Math.sqrt(radiusSquared))
    }
  }

  getTransforms() {
    return []
  }

  getSelector() {
    return this._selector
  }

  getBoundaries() {
    return this._boundaries
  }

  finalize() {}
}

export default BiologicalUnit