import { BufferGeometry } from '../core/BufferGeometry';

import { BufferAttribute } from '../core/BufferAttribute';

/**

* @author mrdoob / http://mrdoob.com/

*/

function WireframeGeometry( geometry ) {

BufferGeometry.call( this );

var edge = [ 0, 0 ], hash = {};

function sortFunction( a, b ) {

return a - b;

}

var keys = [ 'a', 'b', 'c' ];

if ( (geometry && geometry.isGeometry) ) {

var vertices = geometry.vertices;

var faces = geometry.faces;

var numEdges = 0;

// allocate maximal size

var edges = new Uint32Array( 6 * faces.length );

for ( var i = 0, l = faces.length; i < l; i ++ ) {

var face = faces[ i ];

for ( var j = 0; j < 3; j ++ ) {

edge[ 0 ] = face[ keys[ j ] ];

edge[ 1 ] = face[ keys[ ( j + 1 ) % 3 ] ];

edge.sort( sortFunction );

var key = edge.toString();

if ( hash[ key ] === undefined ) {

edges[ 2 * numEdges ] = edge[ 0 ];

edges[ 2 * numEdges + 1 ] = edge[ 1 ];

hash[ key ] = true;

numEdges ++;

}

}

}

var coords = new Float32Array( numEdges * 2 * 3 );

for ( var i = 0, l = numEdges; i < l; i ++ ) {

for ( var j = 0; j < 2; j ++ ) {

var vertex = vertices[ edges [ 2 * i + j ] ];

var index = 6 * i + 3 * j;

coords[ index + 0 ] = vertex.x;

coords[ index + 1 ] = vertex.y;

coords[ index + 2 ] = vertex.z;

}

}

this.addAttribute( 'position', new BufferAttribute( coords, 3 ) );

} else if ( (geometry && geometry.isBufferGeometry) ) {

if ( geometry.index !== null ) {

// Indexed BufferGeometry

var indices = geometry.index.array;

var vertices = geometry.attributes.position;

var groups = geometry.groups;

var numEdges = 0;

if ( groups.length === 0 ) {

geometry.addGroup( 0, indices.length );

}

// allocate maximal size

var edges = new Uint32Array( 2 * indices.length );

for ( var o = 0, ol = groups.length; o < ol; ++ o ) {

var group = groups[ o ];

var start = group.start;

var count = group.count;

for ( var i = start, il = start + count; i < il; i += 3 ) {

for ( var j = 0; j < 3; j ++ ) {

edge[ 0 ] = indices[ i + j ];

edge[ 1 ] = indices[ i + ( j + 1 ) % 3 ];

edge.sort( sortFunction );

var key = edge.toString();

if ( hash[ key ] === undefined ) {

edges[ 2 * numEdges ] = edge[ 0 ];

edges[ 2 * numEdges + 1 ] = edge[ 1 ];

hash[ key ] = true;

numEdges ++;

}

}

}

}

var coords = new Float32Array( numEdges * 2 * 3 );

for ( var i = 0, l = numEdges; i < l; i ++ ) {

for ( var j = 0; j < 2; j ++ ) {

var index = 6 * i + 3 * j;

var index2 = edges[ 2 * i + j ];

coords[ index + 0 ] = vertices.getX( index2 );

coords[ index + 1 ] = vertices.getY( index2 );

coords[ index + 2 ] = vertices.getZ( index2 );

}

}

this.addAttribute( 'position', new BufferAttribute( coords, 3 ) );

} else {

// non-indexed BufferGeometry

var vertices = geometry.attributes.position.array;

var numEdges = vertices.length / 3;

var numTris = numEdges / 3;

var coords = new Float32Array( numEdges * 2 * 3 );

for ( var i = 0, l = numTris; i < l; i ++ ) {

for ( var j = 0; j < 3; j ++ ) {

var index = 18 * i + 6 * j;

var index1 = 9 * i + 3 * j;

coords[ index + 0 ] = vertices[ index1 ];

coords[ index + 1 ] = vertices[ index1 + 1 ];

coords[ index + 2 ] = vertices[ index1 + 2 ];

var index2 = 9 * i + 3 * ( ( j + 1 ) % 3 );

coords[ index + 3 ] = vertices[ index2 ];

coords[ index + 4 ] = vertices[ index2 + 1 ];

coords[ index + 5 ] = vertices[ index2 + 2 ];

}

}

this.addAttribute( 'position', new BufferAttribute( coords, 3 ) );

}

}

}

WireframeGeometry.prototype = Object.create( BufferGeometry.prototype );

WireframeGeometry.prototype.constructor = WireframeGeometry;

export { WireframeGeometry };