import {
	markNodeData,
	objectAssign,
	arrayFindIndex,
	getChildState,
	reInitChecked,
	getPropertyFromData,
	isNull,
	NODE_KEY
} from '../tool/util';

const getStore = function(store) {
	let thisStore = store;
	
	return function() {
		return thisStore;
	}
}

let nodeIdSeed = 0;

export default class Node {
	constructor(options) {
		this.time = new Date().getTime();
		this.id = nodeIdSeed++;
		this.text = null;
		this.checked = false;
		this.indeterminate = false;
		this.data = null;
		this.expanded = false;
		this.parentId = null;
		this.visible = true;
		this.isCurrent = false;

		for (let name in options) {
			if (options.hasOwnProperty(name)) {
				if (name === 'store') {
					this.store = getStore(options[name]);
				} else {
					this[name] = options[name];
				}
			}
		}
		
		if (!this.store()) {
			throw new Error('[Node]store is required!');
		}

		// internal
		this.level = 0;
		this.loaded = false;
		this.childNodesId = [];
		this.loading = false;
		this.label = getPropertyFromData(this, 'label');
		this.key = this._getKey();
		this.disabled = getPropertyFromData(this, 'disabled');
		this.nextSibling = null;
		this.previousSibling = null;
		this.icon = '';
		
		this._handleParentAndLevel();
		this._handleProps();
		this._handleExpand();
		this._handleCurrent();
		
		if (this.store().lazy) {
			this.store()._initDefaultCheckedNode(this);
		}

		this.updateLeafState();
	}
	
	_getKey() {
		if (!this.data || Array.isArray(this.data)) return null;
		
		if (typeof this.data === 'object') {
			const nodeKey = this.store().key;
			const key = this.data[nodeKey];
			
			if (typeof key === 'undefined') {
				throw new Error(`您配置的node-key为"${nodeKey}"，但数据中并未找到对应"${nodeKey}"属性的值，请检查node-key的配置是否合理`)
			}
			
			return key;
		}
		
		throw new Error('不合法的data数据');
	}
	
	_handleParentAndLevel() {
		if (this.parentId !== null) {
			let parent = this.getParent(this.parentId);
			
			if (this.store().isInjectParentInNode) {
				this.parent = parent;
			}
			
			// 由于这里做了修改，默认第一个对象不会被注册到nodesMap中，所以找不到parent会报错，所以默认parent的level是0
			if (!parent) {
				parent = {
					level: 0
				}
			} else {
				const parentChildNodes = parent.getChildNodes(parent.childNodesId);
				const index = parent.childNodesId.indexOf(this.key);
				this.nextSibling = index > -1 ? parentChildNodes[index + 1] : null;
				this.previousSibling = index > 0 ? parentChildNodes[index - 1] : null;
			}
			this.level = parent.level + 1;
		}
	}
	
	_handleProps() {
		const props = this.store().props;
		
		if (this.store().showNodeIcon) {
			if (props && typeof props.icon !== 'undefined') {
				this.icon = getPropertyFromData(this, 'icon');
			} else {
				console.warn('请配置props属性中的"icon"字段')
			}
		}
		
		this.store().registerNode(this);
		
		if (props && typeof props.isLeaf !== 'undefined') {
			const isLeaf = getPropertyFromData(this, 'isLeaf');
			if (typeof isLeaf === 'boolean') {
				this.isLeafByUser = isLeaf;
			}
		}
	}
	
	_handleExpand() {
		if (this.store().lazy !== true && this.data) {
			this.setData(this.data);
		
			if (this.store().defaultExpandAll) {
				this.expanded = true;
			}
		} else if (this.level > 0 && this.store().lazy && this.store().defaultExpandAll) {
			this.expand();
		}
		
		if (!Array.isArray(this.data)) {
			markNodeData(this, this.data);
		}
		
		if (!this.data) return;
		
		const defaultExpandedKeys = this.store().defaultExpandedKeys;
		const key = this.store().key;
		if (key && defaultExpandedKeys && defaultExpandedKeys.indexOf(this.key) !== -1) {
			this.expand(null, this.store().autoExpandparent);
		}
	}
	
	_handleCurrent() {
		const key = this.store().key;
		
		if (key && this.store().currentNodeKey !== undefined && this.key === this.store().currentNodeKey) {
			this.store().currentNode = this;
			this.store().currentNode.isCurrent = true;
		}
	}
	
	destroyStore() {
		getStore(null)
	}

	setData(data) {
		if (!Array.isArray(data)) {
			markNodeData(this, data);
		}

		this.data = data;
		this.childNodesId = [];

		let children;
		if (this.level === 0 && Array.isArray(this.data)) {
			children = this.data;
		} else {
			children = getPropertyFromData(this, 'children') || [];
		}

		for (let i = 0, j = children.length; i < j; i++) {
			this.insertChild({
				data: children[i]
			});
		}
	}

	contains(target, deep = true) {
		const walk = function(parent) {
			const children = parent.getChildNodes(parent.childNodesId) || [];
			let result = false;
			for (let i = 0, j = children.length; i < j; i++) {
				const child = children[i];
				if (child === target || (deep && walk(child))) {
					result = true;
					break;
				}
			}
			return result;
		};

		return walk(this);
	}

	remove() {
		if (this.parentId !== null) {
			const parent = this.getParent(this.parentId);
			parent.removeChild(this);
		}
	}

	insertChild(child, index, batch) {
		if (!child) throw new Error('insertChild error: child is required.');

		if (!(child instanceof Node)) {
			if (!batch) {
				const children = this.getChildren(true);
				if (children.indexOf(child.data) === -1) {
					if (typeof index === 'undefined' || index < 0) {
						children.push(child.data);
					} else {
						children.splice(index, 0, child.data);
					}
				}
			}
			
			objectAssign(child, {
				parentId: isNull(this.key) ? '' : this.key,
				store: this.store()
			});
			child = new Node(child);
		}

		child.level = this.level + 1;

		if (typeof index === 'undefined' || index < 0) {
			this.childNodesId.push(child.key);
		} else {
			this.childNodesId.splice(index, 0, child.key);
		}

		this.updateLeafState();
	}

	insertBefore(child, ref) {
		let index;
		if (ref) {
			index = this.childNodesId.indexOf(ref.id);
		}
		this.insertChild(child, index);
	}

	insertAfter(child, ref) {
		let index;
		if (ref) {
			index = this.childNodesId.indexOf(ref.id);
			if (index !== -1) index += 1;
		}
		this.insertChild(child, index);
	}

	removeChild(child) {
		const children = this.getChildren() || [];
		const dataIndex = children.indexOf(child.data);
		if (dataIndex > -1) {
			children.splice(dataIndex, 1);
		}
		
		const index = this.childNodesId.indexOf(child.key);
		
		if (index > -1) {
			this.store() && this.store().deregisterNode(child);
			child.parentId = null;
			this.childNodesId.splice(index, 1);
		}
		
		this.updateLeafState();
	}

	removeChildByData(data) {
		let targetNode = null;

		for (let i = 0; i < this.childNodesId.length; i++) {
			let node = this.getChildNodes(this.childNodesId);
			if (node[i].data === data) {
				targetNode = node[i];
				break;
			}
		}

		if (targetNode) {
			this.removeChild(targetNode);
		}
	}

	// 为了避免APP端parent嵌套结构导致报错，这里parent需要从nodesMap中获取
	getParent(parentId) {
		try {
			if (!parentId.toString()) return null;
			return this.store().nodesMap[parentId];
		} catch (error) {
			return null;
		}
	}

	// 为了避免APP端childNodes嵌套结构导致报错，这里childNodes需要从nodesMap中获取
	getChildNodes(childNodesId) {
		let childNodes = [];
		if (childNodesId.length === 0) return childNodes;
		childNodesId.forEach((key) => {
			childNodes.push(this.store().nodesMap[key]);
		})
		return childNodes;
	}

	expand(callback, expandparent) {
		const done = () => {
			if (expandparent) {
				let parent = this.getParent(this.parentId);
				while (parent && parent.level > 0) {
					parent.expanded = true;
					parent = this.getParent(parent.parentId);
				}
			}
			this.expanded = true;
			if (callback) callback();
		};

		if (this.shouldLoadData()) {
			this.loadData(function(data) {
				if (Array.isArray(data)) {
					if (this.checked) {
						this.setChecked(true, true);
					} else if (!this.store().checkStrictly) {
						reInitChecked(this);
					}
					done();
				}
			});
		} else {
			done();
		}
	}

	doCreateChildren(array, defaultProps = {}) {
		array.forEach((item) => {
			this.insertChild(objectAssign({
				data: item
			}, defaultProps), undefined, true);
		});
	}

	collapse() {
		this.expanded = false;
	}

	shouldLoadData() {
		return this.store().lazy === true && this.store().load && !this.loaded;
	}

	updateLeafState() {
		if (this.store().lazy === true && this.loaded !== true && typeof this.isLeafByUser !== 'undefined') {
			this.isLeaf = this.isLeafByUser;
			return;
		}
		const childNodesId = this.childNodesId;
		if (!this.store().lazy || (this.store().lazy === true && this.loaded === true)) {
			this.isLeaf = !childNodesId || childNodesId.length === 0;
			return;
		}
		this.isLeaf = false;
	}

	setChecked(value, deep, recursion, passValue) {
		this.indeterminate = value === 'half';
		this.checked = value === true;
		
		if (this.checked && this.store().expandOnCheckNode) {
			this.expand(null, true)
		}
		
		if (this.store().checkStrictly) return;
		if (this.store().showRadio) return;

		if (!(this.shouldLoadData() && !this.store().checkDescendants)) {
			let childNodes = this.getChildNodes(this.childNodesId);
			let {
				all,
				allWithoutDisable
			} = getChildState(childNodes);

			if (!this.isLeaf && (!all && allWithoutDisable)) {
				this.checked = false;
				value = false;
			}

			const handleDescendants = () => {
				if (deep) {
					let childNodes = this.getChildNodes(this.childNodesId)
					for (let i = 0, j = childNodes.length; i < j; i++) {
						const child = childNodes[i];
						passValue = passValue || value !== false;
						const isCheck = child.disabled ? child.checked : passValue;
						child.setChecked(isCheck, deep, true, passValue);
					}
					const {
						half,
						all
					} = getChildState(childNodes);
					
					if (!all) {
						this.checked = all;
						this.indeterminate = half;
					}
				}
			};

			if (this.shouldLoadData()) {
				this.loadData(() => {
					handleDescendants();
					reInitChecked(this);
				}, {
					checked: value !== false
				});
				return;
			} else {
				handleDescendants();
			}
		}

		if (!this.parentId) return;

		let parent = this.getParent(this.parentId);
		if (parent && parent.level === 0) return;

		if (!recursion) {
			reInitChecked(parent);
		}
	}

	setRadioChecked(value) {
		const allNodes = this.store()._getAllNodes().sort((a, b) => b.level - a.level);
		allNodes.forEach(node => node.setChecked(false, false));
		this.checked = value === true;
	}

	getChildren(forceInit = false) {
		if (this.level === 0) return this.data;
		const data = this.data;
		if (!data) return null;

		const props = this.store().props;
		let children = 'children';
		if (props) {
			children = props.children || 'children';
		}

		if (data[children] === undefined) {
			data[children] = null;
		}

		if (forceInit && !data[children]) {
			data[children] = [];
		}

		return data[children];
	}

	updateChildren() {
		let childNodes = this.getChildNodes(this.childNodesId);
		const newData = this.getChildren() || [];
		const oldData = childNodes.map((node) => node.data);

		const newDataMap = {};
		const newNodes = [];

		newData.forEach((item, index) => {
			const key = item[NODE_KEY];
			const isNodeExists = !!key && arrayFindIndex(oldData, data => data[NODE_KEY] === key) >= 0;
			if (isNodeExists) {
				newDataMap[key] = {
					index,
					data: item
				};
			} else {
				newNodes.push({
					index,
					data: item
				});
			}
		});

		if (!this.store().lazy) {
			oldData.forEach((item) => {
				if (!newDataMap[item[NODE_KEY]]) this.removeChildByData(item);
			});
		}

		newNodes.forEach(({
			index,
			data
		}) => {
			this.insertChild({
				data
			}, index);
		});

		this.updateLeafState();
	}

	loadData(callback, defaultProps = {}) {
		if (this.store().lazy === true && 
			this.store().load && !this.loaded && 
			(!this.loading || Object.keys(defaultProps).length)
		) {
			this.loading = true;

			const resolve = (children) => {
				this.loaded = true;
				this.loading = false;
				this.childNodesId = [];
				this.doCreateChildren(children, defaultProps);
				this.updateLeafState();
				
				callback && callback.call(this,children);
			};

			this.store().load(this, resolve);
		} else {
			callback && callback.call(this);
		}
	}
}