import * as THREE from '../../node_modules/three/src/Three';
import { color } from '../utils/shared'

const lineMaterial = new THREE.LineBasicMaterial({
  linewidth: 2,
  color: color.dimension,
})


const pointMaterial = new THREE.PointsMaterial({
  color: color.dimension,
  size: 4,
})


export async function drawDimension() {
  let pts = await this.awaitPts({ point: 2 })

  if (pts == null) return;

  const line = new THREE.LineSegments(
    new THREE.BufferGeometry().setAttribute('position',
      new THREE.Float32BufferAttribute(3 * 8, 3)
    ),
    lineMaterial.clone()
  );

  const point = new THREE.Points(
    new THREE.BufferGeometry().setAttribute('position',
      new THREE.Float32BufferAttribute(3, 3)
    ),
    pointMaterial.clone()
  )

  line.userData.nids = pts.map(e => e.name)



  let dist = 0
  for (let i = 0; i < 3; i++) {
    dist += (pts[0].geometry.attributes.position.array[i] - pts[1].geometry.attributes.position.array[i]) ** 2
  }
  dist = Math.sqrt(dist)

  this.obj3d.children[1].add(line).add(point)

  const onMove = this._onMoveDimension(point, line)



  point.label = document.createElement('div');
  point.label.textContent = dist.toFixed(3);
  point.label.contentEditable = true;
  this.labelContainer.append(point.label)



  let onEnd, onKey;
  let add = await new Promise((res) => {
    onEnd = (e) => res(true)
    onKey = (e) => e.key == 'Escape' && res(false)

    this.canvas.addEventListener('pointermove', onMove)
    this.canvas.addEventListener('pointerdown', onEnd)
    window.addEventListener('keydown', onKey)
  })

  this.canvas.removeEventListener('pointermove', onMove)
  this.canvas.removeEventListener('pointerdown', onEnd)
  window.removeEventListener('keydown', onKey)
  point.geometry.computeBoundingSphere()
  line.geometry.computeBoundingSphere()
  if (add) {
    this.constraints.set(++this.c_id, //???
      [
        'pt_pt_distance', dist,
        [pts[0].name, pts[1].name, -1, -1]
      ]
    )
    pts[0].userData.constraints.push(this.c_id)
    pts[1].userData.constraints.push(this.c_id)

    this.updateOtherBuffers()

    line.name = this.c_id
    line.userData.type = 'dimension'
    point.name = this.c_id
    point.userData.type = 'dimension'



    point.label.addEventListener('focus', this.updateDim(this.c_id))



  } else {

    this.obj3d.children[1].children.splice(this.obj3d.children[1].length - 2, 2).forEach(
      e => {
        e.geometry.dispose()
        e.material.dispose()
      }
    )
    this.labelContainer.removeChild(this.labelContainer.lastChild);
    sc.render()
  }

  return
}

const p1 = new THREE.Vector2()
const p2 = new THREE.Vector2()
const p3 = new THREE.Vector2()
let dir, hyp, proj, perp, p1e, p2e, nids, _p1, _p2;



export function updateDim(c_id) {
  return (ev_focus) => {
    const value = ev_focus.target.textContent
    document.addEventListener('keydown', (e) => {
      if (e.key == 'Enter') {
        e.preventDefault()
        const ent = this.constraints.get(c_id)
        ent[1] = parseFloat(ev_focus.target.textContent)
        this.constraints.set(c_id, ent)
        this.updateOtherBuffers()
        this.solve()
        sc.render()
        ev_focus.target.blur()
        this.updateBoundingSpheres()
      } else if (e.key == 'Escape') {
        ev_focus.target.textContent = value
        getSelection().empty()
        ev_focus.target.blur()
      }
    })
  }
} 



export function _onMoveDimension(point, line) {

  nids = line.userData.nids

  _p1 = this.obj3d.children[this.objIdx.get(nids[0])].geometry.attributes.position.array
  _p2 = this.obj3d.children[this.objIdx.get(nids[1])].geometry.attributes.position.array

  p1.set(_p1[0], _p1[1])
  p2.set(_p2[0], _p2[1])

  let loc;

  return (e) => {
    loc = this.getLocation(e)

    p3.set(loc.x, loc.y)

    update(
      line.geometry.attributes.position,
      point.geometry.attributes.position
    )

    point.userData.offset = hyp.toArray()

    sc.render()
  }
}


export function setDimLines() {

  const restoreLabels = this.labelContainer.childElementCount == 0;

  const dims = this.obj3d.children[1].children

  let point, dist;
  for (let i = 0; i < dims.length; i += 2) {


    if (restoreLabels) {
      point = dims[i + 1]  // point node is at i+1
      dist = this.constraints.get(point.name)[1]
      point.label = document.createElement('div');
      point.label.textContent = dist.toFixed(3);
      point.label.contentEditable = true;
      this.labelContainer.append(point.label)
  
      point.label.addEventListener('focus', this.updateDim(this.c_id))
    }


    nids = dims[i].userData.nids

    _p1 = this.obj3d.children[this.objIdx.get(nids[0])].geometry.attributes.position.array
    _p2 = this.obj3d.children[this.objIdx.get(nids[1])].geometry.attributes.position.array

    const offset = dims[i + 1].userData.offset

    p1.set(_p1[0], _p1[1])
    p2.set(_p2[0], _p2[1])
    p3.set(_p1[0] + offset[0], _p1[1] + offset[1])


    update(
      dims[i].geometry.attributes.position,
      dims[i + 1].geometry.attributes.position
    )
  }

}

function update(linegeom, pointgeom) {
  dir = p2.clone().sub(p1).normalize()
  hyp = p3.clone().sub(p1)
  proj = dir.multiplyScalar(hyp.dot(dir))
  perp = hyp.clone().sub(proj)

  p1e = p1.clone().add(perp).toArray()
  p2e = p2.clone().add(perp).toArray()

  linegeom.array.set(p1.toArray(), 0)
  linegeom.array.set(p1e, 3)

  linegeom.array.set(p1e, 6)
  linegeom.array.set(p2e, 9)

  linegeom.array.set(p2e, 12)
  linegeom.array.set(p2.toArray(), 15)

  linegeom.array.set(p1e, 18)
  linegeom.array.set(p3.toArray(), 21)

  linegeom.needsUpdate = true;

  pointgeom.array.set(p3.toArray())
  pointgeom.needsUpdate = true;
}