/*
 * @author tamarintech / https://tamarintech.com
 *
 * Description: Early release of an AMF Loader following the pattern of the
 * example loaders in the three.js project.
 *
 * More information about the AMF format: http://amf.wikispaces.com
 *
 * Usage:
 *	var loader = new AMFLoader();
 *	loader.load('/path/to/project.amf', function(objecttree) {
 *		scene.add(objecttree);
 *	});
 *
 * Materials now supported, material colors supported
 * Zip support, requires jszip
 * TextDecoder polyfill required by some browsers (particularly IE, Edge)
 * No constellation support (yet)!
 *
 */

THREE.AMFLoader = function ( manager ) {

	this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;

};

THREE.AMFLoader.prototype = {

	constructor: THREE.AMFLoader,

	load: function ( url, onLoad, onProgress, onError ) {

		var scope = this;

		var loader = new THREE.XHRLoader( scope.manager );
		loader.setCrossOrigin( this.crossOrigin );
		loader.setResponseType( 'arraybuffer' );

		loader.load( url, function( text ) {

			var amfObject = scope.parse( text );
			onLoad( amfObject );

		}, onProgress, onError );

	},

	parse: function ( data ) {

		var amfName = "";
		var amfAuthor = "";
		var amfScale = 1.0;
		var amfMaterials = {};
		var amfObjects = {};

		var xmldata = this._loadDocument( data );

		amfScale = this._loadDocumentScale( xmldata );

		var documentchildren = xmldata.documentElement.children;

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

			if ( documentchildren[ i ].nodeName === 'metadata' ) {

				if ( documentchildren[ i ].attributes[ 'type' ] !== undefined ) {

					if ( documentchildren[ i ].attributes[ 'type' ].value === 'name' ) {

						amfName = documentchildren[ i ].textContent;

					} else if ( documentchildren[ i ].attributes[ 'type' ].value === 'author' ) {

						amfAuthor = documentchildren[ i ].textContent;

					}

				}

			} else if ( documentchildren[ i ].nodeName === 'material' ) {

				var loadedmaterial = this._loadMaterials( documentchildren[ i ] );
				amfMaterials[ loadedmaterial.id ] = loadedmaterial.material;

			} else if ( documentchildren[ i ].nodeName === 'object' ) {

				var loadedobject = this._loadObject( documentchildren[ i ] );
				amfObjects[ loadedobject.id ] = loadedobject.obj;

			}

		}

		var sceneobject = new THREE.Object3D();

		sceneobject.name = amfName;
		sceneobject.userData.author = amfAuthor;
		sceneobject.userData.loader = "AMF";

		var defaultmaterial = new THREE.MeshPhongMaterial( { shading: THREE.FlatShading, color: 0xaaaaff } );

		for ( var objid in amfObjects ) {

			var newobject = new THREE.Object3D();

			for ( var meshi = 0; meshi < amfObjects[ objid ].meshes.length; meshi ++ ) {

				var meshvertices = Float32Array.from( amfObjects[ objid ].meshes[ meshi ].vertices );
				var vertices = new THREE.BufferAttribute( Float32Array.from( meshvertices ), 3 );
				var objdefaultmaterial = defaultmaterial;

				if ( amfObjects[ objid ].meshes[ meshi ].color ) {

					var color = amfObjects[ objid ].meshes[ meshi ].color;
					objdefaultmaterial = defaultmaterial.clone();
					objdefaultmaterial.color = new THREE.Color( color.r, color.g, color.b );

					if ( color.a != 1.0 ) {

						objdefaultmaterial.transparent = true;
						objdefaultmaterial.opacity = color.a;

					}

				}

				for ( var voli = 0; voli < amfObjects[ objid ].meshes[ meshi ].volumes.length; voli ++ ) {

					var currvolume = amfObjects[ objid ].meshes[ meshi ].volumes[ voli ];
					var newgeometry = new THREE.BufferGeometry();
					var indexes = Uint32Array.from( currvolume.triangles );
					var normals = new Uint32Array( vertices.array.length );

					var material = objdefaultmaterial;

					newgeometry.setIndex( new THREE.BufferAttribute( indexes, 1 ) );
					newgeometry.addAttribute( 'position', vertices.clone() );

					if ( amfMaterials[ currvolume.materialid ] !== undefined ) {

						material = amfMaterials[ currvolume.materialid ];

					}

					newgeometry.scale( amfScale, amfScale, amfScale );

					var newmesh = new THREE.Mesh( newgeometry, material.clone() );

					newobject.add( newmesh );

				}

			}
			sceneobject.add( newobject );

		}

		return sceneobject;

	},

	_loadDocument: function ( data ) {

		var view = new DataView( data );

		var magic = String.fromCharCode( view.getUint8( 0 ), view.getUint8( 1 ) );

		if ( magic === "PK" ) {

			console.log( "Loading Zip" );
			var zip = null;
			var file = null;

			try {

				zip = new JSZip( data );

			} catch ( e ) {

				if ( e instanceof ReferenceError ) {

					console.log( "	jszip missing and file is compressed." );
					return null;

				}

			}

			for ( file in zip.files ) {

				if ( file.toLowerCase().endsWith( ".amf" ) ) {

					break;

				}

			}

			console.log( "	Trying to load file asset: " + file );
			view = new DataView( zip.file( file ).asArrayBuffer() );

		}

		if ( TextDecoder === undefined ) {

			console.log( "	TextDecoder not present.	Please use TextDecoder polyfill." );
			return null;

		}

		var filetext = new TextDecoder( 'utf-8' ).decode( view );

		var xmldata = new DOMParser().parseFromString( filetext, 'application/xml' );

		if ( xmldata.documentElement.nodeName.toLowerCase() !== "amf" ) {

			console.log( "	Error loading AMF - no AMF document found." );
			return null;

		}

		return xmldata;

	},

	_loadDocumentScale: function ( xmldata ) {

		var scale = 1.0;

		var unit = 'millimeter';

		if ( xmldata.documentElement.attributes[ 'unit' ] !== undefined ) {

			unit = xmldata.documentElement.attributes[ 'unit' ].value.toLowerCase();

		}

		var scale_units = {
			'millimeter': 1.0,
			'inch': 25.4,
			'feet': 304.8,
			'meter': 1000.0,
			'micron': 0.001
		};

		if ( scale_units[ unit ] !== undefined ) {

			scale = scale_units[ unit ];

		}

		console.log( "	Unit scale: " + scale );
		return scale;

	},

	_loadMaterials: function ( node ) {

		var mat = node;

		var loadedmaterial = null;
		var matname = "AMF Material";
		var matid = mat.attributes[ 'id' ].textContent;
		var color;

		for ( var i = 0; i < mat.children.length; i ++ ) {

			var matchildel = mat.children[ i ];

			if ( matchildel.nodeName === "metadata" && matchildel.attributes[ 'type' ] !== undefined ) {

				if ( matchildel.attributes[ 'type' ].value === 'name' ) {

					matname = matchildel.textContent;

				}

			} else if ( matchildel.nodeName === 'color' ) {

				color = this._loadColor( matchildel );

			}

		}

		loadedmaterial = new THREE.MeshPhongMaterial( {
			shading: THREE.FlatShading,
			color: new THREE.Color( color.r, color.g, color.b ),
			name: matname } );

		if ( color.opacity !== 1.0 ) {

			loadedmaterial.transparent = true;
			loadedmaterial.opacity = color.opacity;

		}

		return { 'id': matid, 'material': loadedmaterial };

	},

	_loadColor: function ( node ) {

		var color = { 'r': 1.0, 'g': 1.0, 'b': 1.0, 'a': 1.0, opacity: 1.0 };

		for ( var i = 0; i < node.children.length; i ++ ) {

			var matcolor = node.children[ i ];

			if ( matcolor.nodeName === 'r' ) {

				color.r = matcolor.textContent;

			} else if ( matcolor.nodeName === 'g' ) {

				color.g = matcolor.textContent;

			} else if ( matcolor.nodeName === 'b' ) {

				color.b = matcolor.textContent;

			} else if ( matcolor.nodeName === 'a' ) {

				color.opacity = matcolor.textContent;

			}

		}

		return color;

	},

	_loadMeshVolume: function( node ) {

		var volume = { "name": "", "triangles": [], "materialid": null };

		var currvolumenode = node.firstElementChild;

		if ( node.attributes[ 'materialid' ] !== undefined ) {

			volume.materialid = node.attributes[ 'materialid' ].nodeValue;

		}

		while ( currvolumenode ) {

			if ( currvolumenode.nodeName === "metadata" ) {

				if ( currvolumenode.attributes[ 'type' ] !== undefined ) {

					if ( currvolumenode.attributes[ 'type' ].value === 'name' ) {

						volume.name = currvolumenode.textContent;

					}

				}

			} else if ( currvolumenode.nodeName === "triangle" ) {

				var trianglenode = currvolumenode.firstElementChild;

				while ( trianglenode ) {

					if ( trianglenode.nodeName === "v1" ||
							trianglenode.nodeName === "v2" ||
							trianglenode.nodeName === "v3" ) {

						volume.triangles.push( trianglenode.textContent );

					}

					trianglenode = trianglenode.nextElementSibling;

				}

			}
			currvolumenode = currvolumenode.nextElementSibling;

		}

		return volume;

	},

	_loadMeshVertices: function( node ) {

		var vert_array = [];

		var currverticesnode = node.firstElementChild;

		while ( currverticesnode ) {

			if ( currverticesnode.nodeName === "vertex" ) {

				var vnode = currverticesnode.firstElementChild;

				while ( vnode ) {

					if ( vnode.nodeName === "coordinates" ) {

						var coordnode = vnode.firstElementChild;

						while ( coordnode ) {

							if ( coordnode.nodeName === "x" ||
									coordnode.nodeName === "y" ||
									coordnode.nodeName === "z" ) {

								vert_array.push( coordnode.textContent );

							}

							coordnode = coordnode.nextElementSibling;

						}

					}
					vnode = vnode.nextElementSibling;

				}

			}
			currverticesnode = currverticesnode.nextElementSibling;

		}

		return vert_array;

	},

	_loadObject: function ( node ) {

		"use strict";

		var objid = node.attributes[ 'id' ].textContent;
		var loadedobject = { "name": "amfobject", "meshes": [] };

		var currcolor = null;

		var currobjnode = node.firstElementChild;

		while ( currobjnode ) {

			if ( currobjnode.nodeName === "metadata" ) {

				if ( currobjnode.attributes[ 'type' ] !== undefined ) {

					if ( currobjnode.attributes[ 'type' ].value === 'name' ) {

						loadedobject.name = currobjnode.textContent;

					}

				}

			} else if ( currobjnode.nodeName === "color" ) {

				currcolor = this._loadColor( currobjnode );

			} else if ( currobjnode.nodeName === "mesh" ) {

				var currmeshnode = currobjnode.firstElementChild;
				var mesh = { "vertices": [], "volumes": [], "color": currcolor };

				while ( currmeshnode ) {

					if ( currmeshnode.nodeName === "vertices" ) {

						mesh.vertices = mesh.vertices.concat( this._loadMeshVertices( currmeshnode ) );

					} else if ( currmeshnode.nodeName === "volume" ) {

						mesh.volumes.push( this._loadMeshVolume( currmeshnode ) );

					}

					currmeshnode = currmeshnode.nextElementSibling;

				}

				loadedobject.meshes.push( mesh );

			}

			currobjnode = currobjnode.nextElementSibling;

		}

		return { 'id': objid, 'obj': loadedobject };

	}
};