/*
 * @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.length);

					var material = objdefaultmaterial;

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

					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 = 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 };
	}
};