html.js

/*
Copyright (C) 2011 by Erik Vold

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/

"use strict";

var html = (function() {
  var templates = {};

  var bind = function(func) {
    var slice = Array.prototype.slice,
        args = slice.call(arguments, 1);
    return function() {
      return func.apply({}, args.concat(slice.call(arguments)));
    };
  };

  function Element(tagName, attrs) {
    var ele = document.createElement(tagName);
    for (var attr in attrs) ele.setAttribute(attr, attrs[attr]);
    return ele;
  }

  var observe;
  if (window.addEventListener) {
    observe = function(ele, type, func) {
      ele.addEventListener(type, func, false)
    };
  } else {
    observe = function(ele, type, func) {ele.attachEvent("on" + type, func)};
  }

  function html(tagName, attrs) {
    var ele = event, events = {}, value, eventMatch = /^on(.+)/i;

    if (attrs && (typeof attrs === "string"
        || typeof attrs.nodeType === "number"))
      return html.appendChildren(new Element(tagName), arguments, 1);

    var oldAttrs = attrs;
    attrs = {};
    for (var prop in oldAttrs) {
      if ((event = prop.match(eventMatch))
          && typeof oldAttrs[prop] === "function")
        events[event[1]] = oldAttrs[prop];
      else if (oldAttrs[prop] !== undefined)
        attrs[prop] = oldAttrs[prop];
    }

    var ele = new Element(tagName, attrs);
    for (var event in events) observe(ele, event, events[event])

    return html.appendChildren(ele, arguments, 2);
  };

  html.appendChildren =
      function html_appendChildren(ele, children, startIndex) {
    for (var i = startIndex || 0, child; child = children[i]; i++) {
      switch(Object.prototype.toString.call(child)) {
        case "[object Undefined]":
          continue;
        case "[object String]":
          ele.appendChild(document.createTextNode(child));
          break;
        case "[object Array]":
          html.appendChildren(ele, child);
          break;
        default:
          ele.appendChild(child);
          break;
      }
    }
    return ele;
  }

  html.register = function html_register(aKey, aFunc) {
    return templates[aKey] = aFunc;
  };

  html.render = function html_render(aKey, aData) {
    var template = templates[aKey];
    if (!template)
      throw new Error("There is no template with the key '" + aKey + "'");

    if ("[object Array]" == Object.prototype.toString.call(aData)) {
      var rtn = [];
      for (var i = 0, len = aData.length; i < len; i++)
        rtn.push(template(aData[i]));
      return rtn;
    } else {
      return template(aData);
    }
  };

  html.exportTags = function html_exportTags(aTags) {
    if ("[object String]" == Object.prototype.toString.call(aTags))
      aTags = [aTags];

    var rtn = {};
    for (var i = 0, tag; tag = aTags[i]; i++)
      rtn[tag] = bind(html_tag, tag);
    return rtn;
  };

  return html;
})();