/**
 * Builds one or many THREE.Mesh from one raw set of Arraybuffers, materialGroup descriptions and further parameters.
 * Supports vertex, vertexColor, normal, uv and index buffers.
 * @class
 */
THREE.LoaderSupport.MeshBuilder = (function () {

	var LOADER_MESH_BUILDER_VERSION = '1.2.0';

	var Validator = THREE.LoaderSupport.Validator;

	function MeshBuilder() {
		console.info( 'Using THREE.LoaderSupport.MeshBuilder version: ' + LOADER_MESH_BUILDER_VERSION );
		this.logging = {
			enabled: true,
			debug: false
		};

		this.callbacks = new THREE.LoaderSupport.Callbacks();
		this.materials = [];
	}

	/**
	 * Enable or disable logging in general (except warn and error), plus enable or disable debug logging.
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 * @param {boolean} enabled True or false.
	 * @param {boolean} debug True or false.
	 */
	MeshBuilder.prototype.setLogging = function ( enabled, debug ) {
		this.logging.enabled = enabled === true;
		this.logging.debug = debug === true;
	};

	/**
	 * Initializes the MeshBuilder (currently only default material initialisation).
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 */
	MeshBuilder.prototype.init = function () {
		var defaultMaterial = new THREE.MeshStandardMaterial( { color: 0xDCF1FF } );
		defaultMaterial.name = 'defaultMaterial';

		var defaultVertexColorMaterial = new THREE.MeshStandardMaterial( { color: 0xDCF1FF } );
		defaultVertexColorMaterial.name = 'defaultVertexColorMaterial';
		defaultVertexColorMaterial.vertexColors = THREE.VertexColors;

		var defaultLineMaterial = new THREE.LineBasicMaterial();
		defaultLineMaterial.name = 'defaultLineMaterial';

		var defaultPointMaterial = new THREE.PointsMaterial( { size: 1 } );
		defaultPointMaterial.name = 'defaultPointMaterial';

		var runtimeMaterials = {};
		runtimeMaterials[ defaultMaterial.name ] = defaultMaterial;
		runtimeMaterials[ defaultVertexColorMaterial.name ] = defaultVertexColorMaterial;
		runtimeMaterials[ defaultLineMaterial.name ] = defaultLineMaterial;
		runtimeMaterials[ defaultPointMaterial.name ] = defaultPointMaterial;

		this.updateMaterials(
			{
				cmd: 'materialData',
				materials: {
					materialCloneInstructions: null,
					serializedMaterials: null,
					runtimeMaterials: runtimeMaterials
				}
			}
		);
	};

	/**
	 * Set materials loaded by any supplier of an Array of {@link THREE.Material}.
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 * @param {THREE.Material[]} materials Array of {@link THREE.Material}
	 */
	MeshBuilder.prototype.setMaterials = function ( materials ) {
		var payload = {
			cmd: 'materialData',
			materials: {
				materialCloneInstructions: null,
				serializedMaterials: null,
				runtimeMaterials: Validator.isValid( this.callbacks.onLoadMaterials ) ? this.callbacks.onLoadMaterials( materials ) : materials
			}
		};
		this.updateMaterials( payload );
	};

	MeshBuilder.prototype._setCallbacks = function ( callbacks ) {
		if ( Validator.isValid( callbacks.onProgress ) ) this.callbacks.setCallbackOnProgress( callbacks.onProgress );
		if ( Validator.isValid( callbacks.onMeshAlter ) ) this.callbacks.setCallbackOnMeshAlter( callbacks.onMeshAlter );
		if ( Validator.isValid( callbacks.onLoad ) ) this.callbacks.setCallbackOnLoad( callbacks.onLoad );
		if ( Validator.isValid( callbacks.onLoadMaterials ) ) this.callbacks.setCallbackOnLoadMaterials( callbacks.onLoadMaterials );
	};

	/**
	 * Delegates processing of the payload (mesh building or material update) to the corresponding functions (BW-compatibility).
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 * @param {Object} payload Raw Mesh or Material descriptions.
	 * @returns {THREE.Mesh[]} mesh Array of {@link THREE.Mesh} or null in case of material update
	 */
	MeshBuilder.prototype.processPayload = function ( payload ) {
		if ( payload.cmd === 'meshData' ) {

			return this.buildMeshes( payload );

		} else if ( payload.cmd === 'materialData' ) {

			this.updateMaterials( payload );
			return null;

		}
	};

	/**
	 * Builds one or multiple meshes from the data described in the payload (buffers, params, material info).
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 * @param {Object} meshPayload Raw mesh description (buffers, params, materials) used to build one to many meshes.
	 * @returns {THREE.Mesh[]} mesh Array of {@link THREE.Mesh}
	 */
	MeshBuilder.prototype.buildMeshes = function ( meshPayload ) {
		var meshName = meshPayload.params.meshName;

		var bufferGeometry = new THREE.BufferGeometry();
		bufferGeometry.addAttribute( 'position', new THREE.BufferAttribute( new Float32Array( meshPayload.buffers.vertices ), 3 ) );
		if ( Validator.isValid( meshPayload.buffers.indices ) ) {

			bufferGeometry.setIndex( new THREE.BufferAttribute( new Uint32Array( meshPayload.buffers.indices ), 1 ));

		}
		var haveVertexColors = Validator.isValid( meshPayload.buffers.colors );
		if ( haveVertexColors ) {

			bufferGeometry.addAttribute( 'color', new THREE.BufferAttribute( new Float32Array( meshPayload.buffers.colors ), 3 ) );

		}
		if ( Validator.isValid( meshPayload.buffers.normals ) ) {

			bufferGeometry.addAttribute( 'normal', new THREE.BufferAttribute( new Float32Array( meshPayload.buffers.normals ), 3 ) );

		} else {

			bufferGeometry.computeVertexNormals();

		}
		if ( Validator.isValid( meshPayload.buffers.uvs ) ) {

			bufferGeometry.addAttribute( 'uv', new THREE.BufferAttribute( new Float32Array( meshPayload.buffers.uvs ), 2 ) );

		}

		var material, materialName, key;
		var materialNames = meshPayload.materials.materialNames;
		var createMultiMaterial = meshPayload.materials.multiMaterial;
		var multiMaterials = [];
		for ( key in materialNames ) {

			materialName = materialNames[ key ];
			material = this.materials[ materialName ];
			if ( createMultiMaterial ) multiMaterials.push( material );

		}
		if ( createMultiMaterial ) {

			material = multiMaterials;
			var materialGroups = meshPayload.materials.materialGroups;
			var materialGroup;
			for ( key in materialGroups ) {

				materialGroup = materialGroups[ key ];
				bufferGeometry.addGroup( materialGroup.start, materialGroup.count, materialGroup.index );

			}

		}

		var meshes = [];
		var mesh;
		var callbackOnMeshAlter = this.callbacks.onMeshAlter;
		var callbackOnMeshAlterResult;
		var useOrgMesh = true;
		var geometryType = Validator.verifyInput( meshPayload.geometryType, 0 );
		if ( Validator.isValid( callbackOnMeshAlter ) ) {

			callbackOnMeshAlterResult = callbackOnMeshAlter(
				{
					detail: {
						meshName: meshName,
						bufferGeometry: bufferGeometry,
						material: material,
						geometryType: geometryType
					}
				}
			);
			if ( Validator.isValid( callbackOnMeshAlterResult ) ) {

				if ( ! callbackOnMeshAlterResult.isDisregardMesh() && callbackOnMeshAlterResult.providesAlteredMeshes() ) {

					for ( var i in callbackOnMeshAlterResult.meshes ) {

						meshes.push( callbackOnMeshAlterResult.meshes[ i ] );

					}

				}
				useOrgMesh = false;

			}

		}
		if ( useOrgMesh ) {

			if ( meshPayload.computeBoundingSphere ) bufferGeometry.computeBoundingSphere();
			if ( geometryType === 0 ) {

				mesh = new THREE.Mesh( bufferGeometry, material );

			} else if ( geometryType === 1) {

				mesh = new THREE.LineSegments( bufferGeometry, material );

			} else {

				mesh = new THREE.Points( bufferGeometry, material );

			}
			mesh.name = meshName;
			meshes.push( mesh );

		}

		var progressMessage;
		if ( Validator.isValid( meshes ) && meshes.length > 0 ) {

			var meshNames = [];
			for ( var i in meshes ) {

				mesh = meshes[ i ];
				meshNames[ i ] = mesh.name;

			}
			progressMessage = 'Adding mesh(es) (' + meshNames.length + ': ' + meshNames + ') from input mesh: ' + meshName;
			progressMessage += ' (' + ( meshPayload.progress.numericalValue * 100 ).toFixed( 2 ) + '%)';

		} else {

			progressMessage = 'Not adding mesh: ' + meshName;
			progressMessage += ' (' + ( meshPayload.progress.numericalValue * 100 ).toFixed( 2 ) + '%)';

		}
		var callbackOnProgress = this.callbacks.onProgress;
		if ( Validator.isValid( callbackOnProgress ) ) {

			var event = new CustomEvent( 'MeshBuilderEvent', {
				detail: {
					type: 'progress',
					modelName: meshPayload.params.meshName,
					text: progressMessage,
					numericalValue: meshPayload.progress.numericalValue
				}
			} );
			callbackOnProgress( event );

		}

		return meshes;
	};

	/**
	 * Updates the materials with contained material objects (sync) or from alteration instructions (async).
	 * @memberOf THREE.LoaderSupport.MeshBuilder
	 *
	 * @param {Object} materialPayload Material update instructions
	 */
	MeshBuilder.prototype.updateMaterials = function ( materialPayload ) {
		var material, materialName;
		var materialCloneInstructions = materialPayload.materials.materialCloneInstructions;
		if ( Validator.isValid( materialCloneInstructions ) ) {

			var materialNameOrg = materialCloneInstructions.materialNameOrg;
			var materialOrg = this.materials[ materialNameOrg ];

			if ( Validator.isValid( materialNameOrg ) ) {

				material = materialOrg.clone();

				materialName = materialCloneInstructions.materialName;
				material.name = materialName;

				var materialProperties = materialCloneInstructions.materialProperties;
				for ( var key in materialProperties ) {

					if ( material.hasOwnProperty( key ) && materialProperties.hasOwnProperty( key ) ) material[ key ] = materialProperties[ key ];

				}
				this.materials[ materialName ] = material;

			} else {

				console.warn( 'Requested material "' + materialNameOrg + '" is not available!' );

			}
		}

		var materials = materialPayload.materials.serializedMaterials;
		if ( Validator.isValid( materials ) && Object.keys( materials ).length > 0 ) {

			var loader = new THREE.MaterialLoader();
			var materialJson;
			for ( materialName in materials ) {

				materialJson = materials[ materialName ];
				if ( Validator.isValid( materialJson ) ) {

					material = loader.parse( materialJson );
					if ( this.logging.enabled ) console.info( 'De-serialized material with name "' + materialName + '" will be added.' );
					this.materials[ materialName ] = material;
				}

			}

		}

		materials = materialPayload.materials.runtimeMaterials;
		if ( Validator.isValid( materials ) && Object.keys( materials ).length > 0 ) {

			for ( materialName in materials ) {

				material = materials[ materialName ];
				if ( this.logging.enabled ) console.info( 'Material with name "' + materialName + '" will be added.' );
				this.materials[ materialName ] = material;

			}

		}
	};

	/**
	 * Returns the mapping object of material name and corresponding jsonified material.
	 *
	 * @returns {Object} Map of Materials in JSON representation
	 */
	MeshBuilder.prototype.getMaterialsJSON = function () {
		var materialsJSON = {};
		var material;
		for ( var materialName in this.materials ) {

			material = this.materials[ materialName ];
			materialsJSON[ materialName ] = material.toJSON();
		}

		return materialsJSON;
	};

	/**
	 * Returns the mapping object of material name and corresponding material.
	 *
	 * @returns {Object} Map of {@link THREE.Material}
	 */
	MeshBuilder.prototype.getMaterials = function () {
		return this.materials;
	};

	return MeshBuilder;
})();