/*
 * GeometryMerger.js
 *
 * @author realor
 */

import { ObjectBuilder } from './ObjectBuilder.js'
import { SolidBuilder } from './SolidBuilder.js'
import { SolidGeometry } from '../core/SolidGeometry.js'
import { Solid } from '../core/Solid.js'
import { Profile } from '../core/Profile.js'
import { Cord } from '../core/Cord.js'
import { GeometryUtils } from '../utils/GeometryUtils.js'
import * as THREE from '../lib/three.module.js'

class GeometryMerger extends ObjectBuilder {
    static MESHES_NAME = 'merged_meshes'
    static LINES_NAME = 'merged_lines'

    constructor() {
        super()
        this._triangle = [new THREE.Vector3(), new THREE.Vector3(), new THREE.Vector3()]
        this._vector = new THREE.Vector3()
        this._material = null
    }

    performBuild(object) {
        const triangles = []
        const normals = []
        const edges = []
        const matrix = new THREE.Matrix4()

        let mesh = object.getObjectByName(GeometryMerger.MESHES_NAME)
        if (mesh) {
            mesh.geometry.dispose()
            object.remove(mesh)
        }

        let lines = object.getObjectByName(GeometryMerger.LINES_NAME)
        if (lines) {
            lines.geometry.dispose()
            object.remove(lines)
        }

        for (let child of object.children) {
            this.collectGeometry(child, matrix, triangles, normals, edges)
            child.visible = false
        }

        /* meshes */
        const meshGeometry = new THREE.BufferGeometry()

        meshGeometry.setAttribute('position', new THREE.Float32BufferAttribute(triangles, 3))
        meshGeometry.setAttribute('normal', new THREE.Float32BufferAttribute(normals, 3))

        mesh = new THREE.Mesh(meshGeometry, this._material)
        mesh.name = GeometryMerger.MESHES_NAME
        mesh.raycast = function() {}

        object.add(mesh)

        /* lines */
        const linesGeometry = new THREE.BufferGeometry()

        linesGeometry.setAttribute('position', new THREE.Float32BufferAttribute(edges, 3))

        lines = new THREE.LineSegments(linesGeometry, Solid.EdgeMaterial)
        lines.name = GeometryMerger.LINES_NAME
        lines.raycast = function() {}

        object.add(lines)

        return true
    }

    copy(source) {
        return this
    }

    collectGeometry(object, baseMatrix, triangles, normals, edges) {
        const triangle = this._triangle
        const normal = this._vector
        const vector = this._vector
        const matrix = new THREE.Matrix4()
        matrix.copy(baseMatrix)
        matrix.multiply(object.matrix)

        if (object instanceof Solid) {
            const solid = object

            if (solid.facesVisible) {
                const vertices = solid.geometry.vertices
                for (let face of solid.geometry.faces) {
                    let faceTriangles = face.getTriangles()
                    for (let t of faceTriangles) {
                        for (let i = 0; i < 3; i++) {
                            triangle[i].copy(vertices[t[i]]).applyMatrix4(matrix)
                        }

                        GeometryUtils.calculateNormal(triangle, undefined, normal)

                        for (let i = 0; i < 3; i++) {
                            triangles.push(triangle[i].x, triangle[i].y, triangle[i].z)
                            normals.push(normal.x, normal.y, normal.z)
                        }
                    }
                }
            }

            if (solid.edgesVisible) {
                const array = solid.edgesGeometry.attributes.position.array
                for (let i = 0; i < array.length; i += 3) {
                    vector.set(array[i], array[i + 1], array[i + 2])
                    vector.applyMatrix4(matrix)
                    edges.push(vector.x, vector.y, vector.z)
                }
            }

            if (this._material === null) {
                this._material = solid.material
            }
        } else if (object instanceof Profile) {
        } else if (object instanceof Cord) {
        } else {
            for (let child of object.children) {
                this.collectGeometry(child, matrix, triangles, normals, edges)
            }
        }
    }
}

ObjectBuilder.addClass(GeometryMerger)

export { GeometryMerger }