/*
* @Author: 陶秋峰
* @Date:   2016-01-08 08:37:10
* @Last Modified by:   陶秋峰
* @Last Modified time: 2016-01-08 08:50:09
* @CopyRight 蛮蛮工作室
*/
import global from './global';
import * as dom from './dom';
let window: Window = global;

export function empty(node: HTMLElement | string): void {
	let el = dom.by_id(node);
	if("innerHTML" in el){
		try{
			// fast path
			el.innerHTML = "";
			return;
		}catch(e){
			// innerHTML is readOnly (e.g. TABLE (sub)elements in quirks mode)
			// Fall through (saves bytes)
		}
	}

	// SVG/strict elements don't support innerHTML
	for(var c; c = el.lastChild;){ // intentional assignment
		el.removeChild(c);
	}
}

export function to_dom(frag: string): HTMLElement{
	let doc = window.document;
	let master = doc.createElement("div");

	frag += "";

	master.innerHTML = frag;

	// one node shortcut => return the node itself
	if(master.childNodes.length == 1){
		return <HTMLElement>master.removeChild(master.firstChild); // DOMNode
	}

	// return multiple nodes as a document fragment
	let df = doc.createDocumentFragment();
	let fc: Node;
	while((fc = master.firstChild)){ // intentional assignment
		df.appendChild(fc);
	}
	return <HTMLElement>df; // DocumentFragment
};

export enum enum_position {
	before, after,replace,only,first
}

function _insertBefore(/*DomNode*/ node, /*DomNode*/ ref){
	var parent = ref.parentNode;
	if(parent){
		parent.insertBefore(node, ref);
	}
}

function _insertAfter(/*DomNode*/ node, /*DomNode*/ ref){
	// summary:
	//		Try to insert node after ref
	var parent = ref.parentNode;
	if(parent){
		if(parent.lastChild == ref){
			parent.appendChild(node);
		}else{
			parent.insertBefore(node, ref.nextSibling);
		}
	}
}


export function place(id: HTMLElement | string, ref: HTMLElement | string, position?: string | enum_position | number){
	let refNode = dom.by_id(ref);
	let node: HTMLElement;
	if(typeof id == "string"){ // inline'd type check
		node = /^\s*</.test(arguments[0]) ? to_dom(arguments[0]) : dom.by_id(id);
	} else {
		node = arguments[0];
	}
	if(typeof position == "number"){ // inline'd type check
		var cn = refNode.childNodes;
		let p: number = arguments[2];
		if(!cn.length || cn.length <= p){
			refNode.appendChild(node);
		}else{
			_insertBefore(node, cn[p < 0 ? 0 : p]);
		}
	}else{
		switch(position){
			case 'before':
			case enum_position.before:
				_insertBefore(node, refNode);
			break;
			case 'after':
			case enum_position.after:
				_insertAfter(node, refNode);
			break;
			case 'replace':
			case enum_position.replace:
				refNode.parentNode.replaceChild(node, refNode);
			break;
			case enum_position.only:
				empty(refNode);
				refNode.appendChild(node);
			break;
			case 'first':
			case enum_position.first:
				if(refNode.firstChild){
					_insertBefore(node, refNode.firstChild);
					break;
				}
			// else fallthrough...
			default: // aka: last
			refNode.appendChild(node);
		}
	}
	return node; // DomNode
}