import TempNode from '../core/TempNode.js';
import { nodeObject, addNodeElement, tslFn, float, vec2, vec3, vec4 } from '../shadernode/ShaderNode.js';
import { loop } from '../utils/LoopNode.js';
import { uniform } from '../core/UniformNode.js';
import { NodeUpdateType } from '../core/constants.js';
import { threshold } from './ColorAdjustmentNode.js';
import { uv } from '../accessors/UVNode.js';
import { texturePass } from './PassNode.js';
import { Vector2, RenderTarget } from 'three';
import QuadMesh from '../../objects/QuadMesh.js';

const quadMesh = new QuadMesh();

class AnamorphicNode extends TempNode {

	constructor( textureNode, tresholdNode, scaleNode, samples ) {

		super( 'vec4' );

		this.textureNode = textureNode;
		this.tresholdNode = tresholdNode;
		this.scaleNode = scaleNode;
		this.colorNode = vec3( 0.1, 0.0, 1.0 );
		this.samples = samples;
		this.resolution = new Vector2( 1, 1 );

		this._renderTarget = new RenderTarget();
		this._renderTarget.texture.name = 'anamorphic';

		this._invSize = uniform( new Vector2() );

		this._textureNode = texturePass( this, this._renderTarget.texture );

		this.updateBeforeType = NodeUpdateType.RENDER;

	}

	getTextureNode() {

		return this._textureNode;

	}

	setSize( width, height ) {

		this._invSize.value.set( 1 / width, 1 / height );

		width = Math.max( Math.round( width * this.resolution.x ), 1 );
		height = Math.max( Math.round( height * this.resolution.y ), 1 );

		this._renderTarget.setSize( width, height );

	}

	updateBefore( frame ) {

		const { renderer } = frame;

		const textureNode = this.textureNode;
		const map = textureNode.value;

		this._renderTarget.texture.type = map.type;

		const currentRenderTarget = renderer.getRenderTarget();
		const currentTexture = textureNode.value;

		quadMesh.material = this._material;

		this.setSize( map.image.width, map.image.height );

		// render

		renderer.setRenderTarget( this._renderTarget );

		quadMesh.render( renderer );

		// restore

		renderer.setRenderTarget( currentRenderTarget );
		textureNode.value = currentTexture;

	}

	setup( builder ) {

		const textureNode = this.textureNode;

		if ( textureNode.isTextureNode !== true ) {

			console.error( 'AnamorphNode requires a TextureNode.' );

			return vec4();

		}

		//

		const uvNode = textureNode.uvNode || uv();

		const sampleTexture = ( uv ) => textureNode.cache().context( { getUV: () => uv, forceUVContext: true } );

		const anamorph = tslFn( () => {

			const samples = this.samples;
			const halfSamples = Math.floor( samples / 2 );

			const total = vec3( 0 ).toVar();

			loop( { start: - halfSamples, end: halfSamples }, ( { i } ) => {

				const softness = float( i ).abs().div( halfSamples ).oneMinus();

				const uv = vec2( uvNode.x.add( this._invSize.x.mul( i ).mul( this.scaleNode ) ), uvNode.y );
				const color = sampleTexture( uv );
				const pass = threshold( color, this.tresholdNode ).mul( softness );

				total.addAssign( pass );

			} );

			return total.mul( this.colorNode );

		} );

		//

		const material = this._material || ( this._material = builder.createNodeMaterial() );
		material.fragmentNode = anamorph();

		//

		const properties = builder.getNodeProperties( this );
		properties.textureNode = textureNode;

		//

		return this._textureNode;

	}

}

export const anamorphic = ( node, threshold = .9, scale = 3, samples = 32 ) => nodeObject( new AnamorphicNode( nodeObject( node ), nodeObject( threshold ), nodeObject( scale ), samples ) );

addNodeElement( 'anamorphic', anamorphic );

export default AnamorphicNode;