/**
 * @author alteredq / http://alteredqualia.com/
 */
import * as THREE from "../../../../libs/three.js/build/three.module.js";
import CopyShader from './CopyShader'
import {ShaderPass} from './ShaderPass' 
import { MaskPass, ClearMaskPass } from './MaskPass.js'; 


var EffectComposer = function ( renderer, renderTarget ) {

	this.renderer = renderer;

	if ( renderTarget === undefined ) {

		var parameters = {
			minFilter: THREE.LinearFilter,
			magFilter: THREE.LinearFilter,
			format: THREE.RGBAFormat,
			stencilBuffer: false, 
		};

		var size = renderer.getDrawingBufferSize(new THREE.Vector2);
		renderTarget = new THREE.WebGLRenderTarget( size.width, size.height ,  parameters );
		renderTarget.texture.name = 'EffectComposer.rt1';

	}

	this.renderTarget1 = renderTarget;
	this.renderTarget2 = renderTarget.clone();
	this.renderTarget2.texture.name = 'EffectComposer.rt2';

	this.writeBuffer = this.renderTarget1;
	this.readBuffer = this.renderTarget2;

	this.passes = [];

	// dependencies

	/* if ( THREE.CopyShader === undefined ) {

		console.error( 'THREE.EffectComposer relies on THREE.CopyShader' );

	}

	if ( THREE.ShaderPass === undefined ) {

		console.error( 'THREE.EffectComposer relies on THREE.ShaderPass' );

	} */

	this.copyPass = new ShaderPass( CopyShader );
    
    viewer.addEventListener('resize',(e)=>{ //readTarget的话是渲染一整张的，暂时无法一个个viewport渲染所以不用
        this.readTarget || this.setSize(e.viewport.resolution2.x,e.viewport.resolution2.y) //暂时假设composer渲染的viewer的viewports.length == 1
    })
    
};

Object.assign(  EffectComposer.prototype, {

	swapBuffers: function () {

		var tmp = this.readBuffer;
		this.readBuffer = this.writeBuffer;
		this.writeBuffer = tmp;

	},

	addPass: function ( pass ) {

		this.passes.push( pass );

		var size = this.renderer.getDrawingBufferSize(new THREE.Vector2);
		pass.setSize( size.width, size.height );

	},
    
    removePass: function(pass){ //add
        let index = this.passes.indexOf(pass);
        index > -1 && this.passes.splice(index,1)
    },
    
	insertPass: function ( pass, index ) {

		this.passes.splice( index, 0, pass );

	},

	render: function ( scene, camera, viewports, renderFun  ) {

		var maskActive = false;
        let passes = this.passes.filter(e=>e.enabled)
		var pass, i, il = passes.length;
        let oldTarget = this.renderer.getRenderTarget();
        if(this.readTarget && oldTarget){ //add 使用当前renderTarget中的像素  
            this.setSize(oldTarget.width, oldTarget.height)//所有viewports一起渲染，整个画面  因暂时没办法一个个copy
            oldTarget.viewport.set(0, 0, oldTarget.width, oldTarget.height);    
            oldTarget.scissorTest = false
            this.copyPass.render( scene, camera,viewports, this.renderer, this.readBuffer, oldTarget  ); 
        }  
        
		for ( i = 0; i < il; i ++ ) {

			pass = passes[ i ];
 

            //if(i == il-1)pass.renderToScreen = true//
            
			pass.render( scene, camera, viewports, this.renderer, this.writeBuffer, this.readBuffer, maskActive, renderFun );
    
			if ( pass.needsSwap ) {

				if ( maskActive ) {

					var context = this.renderer.context;

					context.stencilFunc( context.NOTEQUAL, 1, 0xffffffff );
                    
					this.copyPass.render(null,null, viewports, this.renderer, this.writeBuffer, this.readBuffer   );// delta 

					context.stencilFunc( context.EQUAL, 1, 0xffffffff );

				}

				this.swapBuffers();

			}

			if ( MaskPass !== undefined ) {

				if ( pass instanceof MaskPass ) {

					maskActive = true;

				} else if ( pass instanceof ClearMaskPass ) {

					maskActive = false;

				}

			}  

		}
        
        this.renderer.setRenderTarget(oldTarget);
        //add
         if(!pass.renderToScreen){ //最后一个如果没有绘制到屏幕or target上
            this.copyPass.renderToScreen = true
            
            this.copyPass.render(null,null, viewports,this.renderer, this.writeBuffer, this.readBuffer)
            
        } 
          
	},

	reset: function ( renderTarget ) {

		if ( renderTarget === undefined ) {

			var size = this.renderer.getDrawingBufferSize(new THREE.Vector2);

			renderTarget = this.renderTarget1.clone();
			renderTarget.setSize( size.width, size.height );

		}

		this.renderTarget1.dispose();
		this.renderTarget2.dispose();
		this.renderTarget1 = renderTarget;
		this.renderTarget2 = renderTarget.clone();

		this.writeBuffer = this.renderTarget1;
		this.readBuffer = this.renderTarget2;

	},

	setSize: function ( width, height, scaleRatio ) {

        scaleRatio = scaleRatio || this.scaleRatio || 1;
        //console.log('setSize', width * scaleRatio, height * scaleRatio)
        let maxTexWidth = 4096
        let w = width * scaleRatio
        let h = height * scaleRatio
        if(w > maxTexWidth || h > maxTexWidth){ //超出会崩溃
            if(w>h){
                scaleRatio = maxTexWidth / width
            }else{
                scaleRatio = maxTexWidth / height
            } 
        } 
        w = width * scaleRatio
        h = height * scaleRatio
        
        
		this.renderTarget1.setSize( w, h );
		this.renderTarget2.setSize( w, h );

		for ( var i = 0; i < this.passes.length; i ++ ) {

			this.passes[ i ].setSize( w, h );

		}

	}

} );


export default EffectComposer