text: import { GPUTextureFormat, GPUAddressMode, GPUFilterMode, GPUTextureDimension } from './constants.js';
  import { CubeTexture, Texture, NearestFilter, NearestMipmapNearestFilter, NearestMipmapLinearFilter, LinearFilter, RepeatWrapping, MirroredRepeatWrapping,
  	RGBAFormat, RedFormat, RGFormat, RGBA_S3TC_DXT1_Format, RGBA_S3TC_DXT3_Format, RGBA_S3TC_DXT5_Format, UnsignedByteType, FloatType, HalfFloatType, sRGBEncoding
  } from 'three';
  import WebGPUTextureUtils from './WebGPUTextureUtils.js';
  
  class WebGPUTextures {
  
  	constructor( device, properties, info ) {
  
  		this.device = device;
  		this.properties = properties;
  		this.info = info;
  
  		this.defaultTexture = null;
  		this.defaultCubeTexture = null;
  		this.defaultSampler = null;
  
  		this.samplerCache = new Map();
  		this.utils = null;
  
  	}
  
  	getDefaultSampler() {
  
  		if ( this.defaultSampler === null ) {
  
  			this.defaultSampler = this.device.createSampler( {} );
  
  		}
  
  		return this.defaultSampler;
  
  	}
  
  	getDefaultTexture() {
  
  		if ( this.defaultTexture === null ) {
  
  			const texture = new Texture();
  			texture.minFilter = NearestFilter;
  			texture.magFilter = NearestFilter;
  
  			this._uploadTexture( texture );
  
  			this.defaultTexture = this.getTextureGPU( texture );
  
  		}
  
  		return this.defaultTexture;
  
  	}
  
  	getDefaultCubeTexture() {
  
  		if ( this.defaultCubeTexture === null ) {
  
  			const texture = new CubeTexture();
  			texture.minFilter = NearestFilter;
  			texture.magFilter = NearestFilter;
  
  			this._uploadTexture( texture );
  
  			this.defaultCubeTexture = this.getTextureGPU( texture );
  
  		}
  
  		return this.defaultCubeTexture;
  
  	}
  
  	getTextureGPU( texture ) {
  
  		const textureProperties = this.properties.get( texture );
  
  		return textureProperties.textureGPU;
  
  	}
  
  	getSampler( texture ) {
  
  		const textureProperties = this.properties.get( texture );
  
  		return textureProperties.samplerGPU;
  
  	}
  
  	updateTexture( texture ) {
  
  		let needsUpdate = false;
  
  		const textureProperties = this.properties.get( texture );
  
  		if ( texture.version > 0 && textureProperties.version !== texture.version ) {
  
  			const image = texture.image;
  
  			if ( image === undefined ) {
  
  				console.warn( 'THREE.WebGPURenderer: Texture marked for update but image is undefined.' );
  
  			} else if ( image.complete === false ) {
  
  				console.warn( 'THREE.WebGPURenderer: Texture marked for update but image is incomplete.' );
  
  			} else {
  
  				// texture init
  
  				if ( textureProperties.initialized === undefined ) {
  
  					textureProperties.initialized = true;
  
  					const disposeCallback = onTextureDispose.bind( this );
  					textureProperties.disposeCallback = disposeCallback;
  
  					texture.addEventListener( 'dispose', disposeCallback );
  
  					this.info.memory.textures ++;
  
  				}
  
  				//
  
  				needsUpdate = this._uploadTexture( texture );
  
  			}
  
  		}
  
  		// if the texture is used for RTT, it's necessary to init it once so the binding
  		// group's resource definition points to the respective GPUTexture
  
  		if ( textureProperties.initializedRTT === false ) {
  
  			textureProperties.initializedRTT = true;
  			needsUpdate = true;
  
  		}
  
  		return needsUpdate;
  
  	}
  
  	updateSampler( texture ) {
  
  		const array = [];
  
  		array.push( texture.wrapS );
  		array.push( texture.wrapT );
  		array.push( texture.wrapR );
  		array.push( texture.magFilter );
  		array.push( texture.minFilter );
  		array.push( texture.anisotropy );
  
  		const key = array.join();
  		let samplerGPU = this.samplerCache.get( key );
  
  		if ( samplerGPU === undefined ) {
  
  			samplerGPU = this.device.createSampler( {
  				addressModeU: this._convertAddressMode( texture.wrapS ),
  				addressModeV: this._convertAddressMode( texture.wrapT ),
  				addressModeW: this._convertAddressMode( texture.wrapR ),
  				magFilter: this._convertFilterMode( texture.magFilter ),
  				minFilter: this._convertFilterMode( texture.minFilter ),
  				mipmapFilter: this._convertFilterMode( texture.minFilter ),
  				maxAnisotropy: texture.anisotropy
  			} );
  
  			this.samplerCache.set( key, samplerGPU );
  
  		}
  
  		const textureProperties = this.properties.get( texture );
  		textureProperties.samplerGPU = samplerGPU;
  
  	}
  
  	initRenderTarget( renderTarget ) {
  
  		const properties = this.properties;
  		const renderTargetProperties = properties.get( renderTarget );
  
  		if ( renderTargetProperties.initialized === undefined ) {
  
  			const device = this.device;
  
  			const width = renderTarget.width;
  			const height = renderTarget.height;
  			const colorTextureFormat = this._getFormat( renderTarget.texture );
  
  			const colorTextureGPU = device.createTexture( {
  				size: {
  					width: width,
  					height: height,
  					depthOrArrayLayers: 1
  				},
  				format: colorTextureFormat,
  				usage: GPUTextureUsage.RENDER_ATTACHMENT | GPUTextureUsage.TEXTURE_BINDING
  			} );
  
  			this.info.memory.textures ++;
  
  			renderTargetProperties.colorTextureGPU = colorTextureGPU;
  			renderTargetProperties.colorTextureFormat = colorTextureFormat;
  
  			// When the ".texture" or ".depthTexture" property of a render target is used as a map,
  			// the renderer has to find the respective GPUTexture objects to setup the bind groups.
  			// Since it's not possible to see just from a texture object whether it belongs to a render
  			// target or not, we need the initializedRTT flag.
  
  			const textureProperties = properties.get( renderTarget.texture );
  			textureProperties.textureGPU = colorTextureGPU;
  			textureProperties.initializedRTT = false;
  
  			if ( renderTarget.depthBuffer === true ) {
  
  				const depthTextureFormat = GPUTextureFormat.Depth24PlusStencil8; // @TODO: Make configurable
  
  				const depthTextureGPU = device.createTexture( {
  					size: {
  						width: width,
  						height: height,
  						depthOrArrayLayers: 1
  					},
  					format: depthTextureFormat,
  					usage: GPUTextureUsage.RENDER_ATTACHMENT
  				} );
  
  				this.info.memory.textures ++;
  
  				renderTargetProperties.depthTextureGPU = depthTextureGPU;
  				renderTargetProperties.depthTextureFormat = depthTextureFormat;
  
  				if ( renderTarget.depthTexture !== null ) {
  
  					const depthTextureProperties = properties.get( renderTarget.depthTexture );
  					depthTextureProperties.textureGPU = depthTextureGPU;
  					depthTextureProperties.initializedRTT = false;
  
  				}
  
  			}
  
  			//
  
  			const disposeCallback = onRenderTargetDispose.bind( this );
  			renderTargetProperties.disposeCallback = disposeCallback;
  
  			renderTarget.addEventListener( 'dispose', disposeCallback );
  
  			//
  
  			renderTargetProperties.initialized = true;
  
  		}
  
  	}
  
  	dispose() {
  
  		this.samplerCache.clear();
  
  	}
  
  	_convertAddressMode( value ) {
  
  		let addressMode = GPUAddressMode.ClampToEdge;
  
  		if ( value === RepeatWrapping ) {
  
  			addressMode = GPUAddressMode.Repeat;
  
  		} else if ( value === MirroredRepeatWrapping ) {
  
  			addressMode = GPUAddressMode.MirrorRepeat;
  
  		}
  
  		return addressMode;
  
  	}
  
  	_convertFilterMode( value ) {
  
  		let filterMode = GPUFilterMode.Linear;
  
  		if ( value === NearestFilter || value === NearestMipmapNearestFilter || value === NearestMipmapLinearFilter ) {
  
  			filterMode = GPUFilterMode.Nearest;
  
  		}
  
  		return filterMode;
  
  	}
  
  	_uploadTexture( texture ) {
  
  		let needsUpdate = false;
  
  		const device = this.device;
  		const image = texture.image;
  
  		const textureProperties = this.properties.get( texture );
  
  		const { width, height, depth } = this._getSize( texture );
  		const needsMipmaps = this._needsMipmaps( texture );
  		const dimension = this._getDimension( texture );
  		const mipLevelCount = this._getMipLevelCount( texture, width, height, needsMipmaps );
  		const format = this._getFormat( texture );
  
  		let usage = GPUTextureUsage.TEXTURE_BINDING | GPUTextureUsage.COPY_DST;
  
  		if ( needsMipmaps === true ) {
  
  			// current mipmap generation requires RENDER_ATTACHMENT
  
  			usage |= GPUTextureUsage.RENDER_ATTACHMENT;
  
  		}
  
  		const textureGPUDescriptor = {
  			size: {
  				width: width,
  				height: height,
  				depthOrArrayLayers: depth,
  			},
  			mipLevelCount: mipLevelCount,
  			sampleCount: 1,
  			dimension: dimension,
  			format: format,
  			usage: usage
  		};
  
  		// texture creation
  
  		let textureGPU = textureProperties.textureGPU;
  
  		if ( textureGPU === undefined ) {
  
  			textureGPU = device.createTexture( textureGPUDescriptor );
  			textureProperties.textureGPU = textureGPU;
  
  			needsUpdate = true;
  
  		}
  
  		// transfer texture data
  
  		if ( texture.isDataTexture || texture.isDataTexture2DArray || texture.isDataTexture3D ) {
  
  			this._copyBufferToTexture( image, format, textureGPU );
  
  			if ( needsMipmaps === true ) this._generateMipmaps( textureGPU, textureGPUDescriptor );
  
  		} else if ( texture.isCompressedTexture ) {
  
  			this._copyCompressedBufferToTexture( texture.mipmaps, format, textureGPU );
  
  		} else if ( texture.isCubeTexture ) {
  
  			this._copyCubeMapToTexture( image, texture, textureGPU );
  
  		} else {
  
  			if ( image !== undefined ) {
  
  				// assume HTMLImageElement, HTMLCanvasElement or ImageBitmap
  
  				this._getImageBitmap( image, texture ).then( imageBitmap => {
  
  					this._copyExternalImageToTexture( imageBitmap, textureGPU );
  
  					if ( needsMipmaps === true ) this._generateMipmaps( textureGPU, textureGPUDescriptor );
  
  				} );
  
  			}
  
  		}
  
  		textureProperties.version = texture.version;
  
  		return needsUpdate;
  
  	}
  
  	_copyBufferToTexture( image, format, textureGPU ) {
  
  		// @TODO: Consider to use GPUCommandEncoder.copyBufferToTexture()
  		// @TODO: Consider to support valid buffer layouts with other formats like RGB
  
  		const data = image.data;
  
  		const bytesPerTexel = this._getBytesPerTexel( format );
  		const bytesPerRow = Math.ceil( image.width * bytesPerTexel / 256 ) * 256;
  
  		this.device.queue.writeTexture(
  			{
  				texture: textureGPU,
  				mipLevel: 0
  			},
  			data,
  			{
  				offset: 0,
  				bytesPerRow
  			},
  			{
  				width: image.width,
  				height: image.height,
  				depthOrArrayLayers: ( image.depth !== undefined ) ? image.depth : 1
  			} );
  
  	}
  
  	_copyCubeMapToTexture( images, texture, textureGPU ) {
  
  		for ( let i = 0; i < images.length; i ++ ) {
  
  			const image = images[ i ];
  
  			this._getImageBitmap( image, texture ).then( imageBitmap => {
  
  				this._copyExternalImageToTexture( imageBitmap, textureGPU, { x: 0, y: 0, z: i } );
  
  			} );
  
  		}
  
  	}
  
  	_copyExternalImageToTexture( image, textureGPU, origin = { x: 0, y: 0, z: 0 } ) {
  
  		this.device.queue.copyExternalImageToTexture(
  			{
  				source: image
  			}, {
  				texture: textureGPU,
  				mipLevel: 0,
  				origin: origin
  			}, {
  				width: image.width,
  				height: image.height,
  				depthOrArrayLayers: 1
  			}
  		);
  
  	}
  
  	_copyCompressedBufferToTexture( mipmaps, format, textureGPU ) {
  
  		// @TODO: Consider to use GPUCommandEncoder.copyBufferToTexture()
  
  		const blockData = this._getBlockData( format );
  
  		for ( let i = 0; i < mipmaps.length; i ++ ) {
  
  			const mipmap = mipmaps[ i ];
  
  			const width = mipmap.width;
  			const height = mipmap.height;
  
  			const bytesPerRow = Math.ceil( width / blockData.width ) * blockData.byteLength;
  
  			this.device.queue.writeTexture(
  				{
  					texture: textureGPU,
  					mipLevel: i
  				},
  				mipmap.data,
  				{
  					offset: 0,
  					bytesPerRow
  				},
  				{
  					width: Math.ceil( width / blockData.width ) * blockData.width,
  					height: Math.ceil( height / blockData.width ) * blockData.width,
  					depthOrArrayLayers: 1,
  				} );
  
  		}
  
  	}
  
  	_generateMipmaps( textureGPU, textureGPUDescriptor ) {
  
  		if ( this.utils === null ) {
  
  			this.utils = new WebGPUTextureUtils( this.device ); // only create this helper if necessary
  
  		}
  
  		this.utils.generateMipmaps( textureGPU, textureGPUDescriptor );
  
  	}
  
  	_getBlockData( format ) {
  
  		// this method is only relevant for compressed texture formats
  
  		if ( format === GPUTextureFormat.BC1RGBAUnorm || format === GPUTextureFormat.BC1RGBAUnormSRGB ) return { byteLength: 8, width: 4, height: 4 }; // DXT1
  		if ( format === GPUTextureFormat.BC2RGBAUnorm || format === GPUTextureFormat.BC2RGBAUnormSRGB ) return { byteLength: 16, width: 4, height: 4 }; // DXT3
  		if ( format === GPUTextureFormat.BC3RGBAUnorm || format === GPUTextureFormat.BC3RGBAUnormSRGB ) return { byteLength: 16, width: 4, height: 4 }; // DXT5
  		if ( format === GPUTextureFormat.BC4RUnorm || format === GPUTextureFormat.BC4RSNorm ) return { byteLength: 8, width: 4, height: 4 }; // RGTC1
  		if ( format === GPUTextureFormat.BC5RGUnorm || format === GPUTextureFormat.BC5RGSnorm ) return { byteLength: 16, width: 4, height: 4 }; // RGTC2
  		if ( format === GPUTextureFormat.BC6HRGBUFloat || format === GPUTextureFormat.BC6HRGBFloat ) return { byteLength: 16, width: 4, height: 4 }; // BPTC (float)
  		if ( format === GPUTextureFormat.BC7RGBAUnorm || format === GPUTextureFormat.BC7RGBAUnormSRGB ) return { byteLength: 16, width: 4, height: 4 }; // BPTC (unorm)
  
  	}
  
  	_getBytesPerTexel( format ) {
  
  		if ( format === GPUTextureFormat.R8Unorm ) return 1;
  		if ( format === GPUTextureFormat.R16Float ) return 2;
  		if ( format === GPUTextureFormat.RG8Unorm ) return 2;
  		if ( format === GPUTextureFormat.RG16Float ) return 4;
  		if ( format === GPUTextureFormat.R32Float ) return 4;
  		if ( format === GPUTextureFormat.RGBA8Unorm || format === GPUTextureFormat.RGBA8UnormSRGB ) return 4;
  		if ( format === GPUTextureFormat.RG32Float ) return 8;
  		if ( format === GPUTextureFormat.RGBA16Float ) return 8;
  		if ( format === GPUTextureFormat.RGBA32Float ) return 16;
  
  	}
  
  	_getDimension( texture ) {
  
  		let dimension;
  
  		if ( texture.isDataTexture3D ) {
  
  			dimension = GPUTextureDimension.ThreeD;
  
  		} else {
  
  			dimension = GPUTextureDimension.TwoD;
  
  		}
  
  		return dimension;
  
  	}
  
  	_getFormat( texture ) {
  
  		const format = texture.format;
  		const type = texture.type;
  		const encoding = texture.encoding;
  
  		let formatGPU;
  
  		switch ( format ) {
  
  			case RGBA_S3TC_DXT1_Format:
  				formatGPU = ( encoding === sRGBEncoding ) ? GPUTextureFormat.BC1RGBAUnormSRGB : GPUTextureFormat.BC1RGBAUnorm;
  				break;
  
  			case RGBA_S3TC_DXT3_Format:
  				formatGPU = ( encoding === sRGBEncoding ) ? GPUTextureFormat.BC2RGBAUnormSRGB : GPUTextureFormat.BC2RGBAUnorm;
  				break;
  
  			case RGBA_S3TC_DXT5_Format:
  				formatGPU = ( encoding === sRGBEncoding ) ? GPUTextureFormat.BC3RGBAUnormSRGB : GPUTextureFormat.BC3RGBAUnorm;
  				break;
  
  			case RGBAFormat:
  
  				switch ( type ) {
  
  					case UnsignedByteType:
  						formatGPU = ( encoding === sRGBEncoding ) ? GPUTextureFormat.RGBA8UnormSRGB : GPUTextureFormat.RGBA8Unorm;
  						break;
  
  					case HalfFloatType:
  						formatGPU = GPUTextureFormat.RGBA16Float;
  						break;
  
  					case FloatType:
  						formatGPU = GPUTextureFormat.RGBA32Float;
  						break;
  
  					default:
  						console.error( 'WebGPURenderer: Unsupported texture type with RGBAFormat.', type );
  
  				}
  
  				break;
  
  			case RedFormat:
  
  				switch ( type ) {
  
  					case UnsignedByteType:
  						formatGPU = GPUTextureFormat.R8Unorm;
  						break;
  
  					case HalfFloatType:
  						formatGPU = GPUTextureFormat.R16Float;
  						break;
  
  					case FloatType:
  						formatGPU = GPUTextureFormat.R32Float;
  						break;
  
  					default:
  						console.error( 'WebGPURenderer: Unsupported texture type with RedFormat.', type );
  
  				}
  
  				break;
  
  			case RGFormat:
  
  				switch ( type ) {
  
  					case UnsignedByteType:
  						formatGPU = GPUTextureFormat.RG8Unorm;
  						break;
  
  					case HalfFloatType:
  						formatGPU = GPUTextureFormat.RG16Float;
  						break;
  
  					case FloatType:
  						formatGPU = GPUTextureFormat.RG32Float;
  						break;
  
  					default:
  						console.error( 'WebGPURenderer: Unsupported texture type with RGFormat.', type );
  
  				}
  
  				break;
  
  			default:
  				console.error( 'WebGPURenderer: Unsupported texture format.', format );
  
  		}
  
  		return formatGPU;
  
  	}
  
  	_getImageBitmap( image, texture ) {
  
  		const width = image.width;
  		const height = image.height;
  
  		if ( ( typeof HTMLImageElement !== 'undefined' && image instanceof HTMLImageElement ) ||
  			( typeof HTMLCanvasElement !== 'undefined' && image instanceof HTMLCanvasElement ) ) {
  
  			const options = {};
  
  			options.imageOrientation = ( texture.flipY === true ) ? 'flipY' : 'none';
  			options.premultiplyAlpha = ( texture.premultiplyAlpha === true ) ? 'premultiply' : 'default';
  
  			return createImageBitmap( image, 0, 0, width, height, options );
  
  		} else {
  
  			// assume ImageBitmap
  
  			return Promise.resolve( image );
  
  		}
  
  	}
  
  	_getMipLevelCount( texture, width, height, needsMipmaps ) {
  
  		let mipLevelCount;
  
  		if ( texture.isCompressedTexture ) {
  
  			mipLevelCount = texture.mipmaps.length;
  
  		} else if ( needsMipmaps === true ) {
  
  			mipLevelCount = Math.floor( Math.log2( Math.max( width, height ) ) ) + 1;
  
  		} else {
  
  			mipLevelCount = 1; // a texture without mipmaps has a base mip (mipLevel 0)
  
  		}
  
  		return mipLevelCount;
  
  	}
  
  	_getSize( texture ) {
  
  		const image = texture.image;
  
  		let width, height, depth;
  
  		if ( texture.isCubeTexture ) {
  
  			width = ( image.length > 0 ) ? image[ 0 ].width : 1;
  			height = ( image.length > 0 ) ? image[ 0 ].height : 1;
  			depth = 6; // one image for each side of the cube map
  
  		} else if ( image !== undefined ) {
  
  			width = image.width;
  			height = image.height;
  			depth = ( image.depth !== undefined ) ? image.depth : 1;
  
  		} else {
  
  			width = height = depth = 1;
  
  		}
  
  		return { width, height, depth };
  
  	}
  
  	_needsMipmaps( texture ) {
  
  		return ( texture.isCompressedTexture !== true ) && ( texture.generateMipmaps === true ) && ( texture.minFilter !== NearestFilter ) && ( texture.minFilter !== LinearFilter );
  
  	}
  
  }
  
  function onRenderTargetDispose( event ) {
  
  	const renderTarget = event.target;
  	const properties = this.properties;
  
  	const renderTargetProperties = properties.get( renderTarget );
  
  	renderTarget.removeEventListener( 'dispose', renderTargetProperties.disposeCallback );
  
  	renderTargetProperties.colorTextureGPU.destroy();
  	properties.remove( renderTarget.texture );
  
  	this.info.memory.textures --;
  
  	if ( renderTarget.depthBuffer === true ) {
  
  		renderTargetProperties.depthTextureGPU.destroy();
  
  		this.info.memory.textures --;
  
  		if ( renderTarget.depthTexture !== null ) {
  
  			properties.remove( renderTarget.depthTexture );
  
  		}
  
  	}
  
  	properties.remove( renderTarget );
  
  }
  
  function onTextureDispose( event ) {
  
  	const texture = event.target;
  
  	const textureProperties = this.properties.get( texture );
  	textureProperties.textureGPU.destroy();
  
  	texture.removeEventListener( 'dispose', textureProperties.disposeCallback );
  
  	this.properties.remove( texture );
  
  	this.info.memory.textures --;
  
  }
  
  export default WebGPUTextures;
  