~function(win, $) {

var px = 'px'
var doc = win.document
var body = doc.body
var docElem = doc.documentElement


$.viewSize = function() { 
    return {
        width: win['innerWidth'] || docElem.clientWidth,
        height: win['innerHeight'] || docElem.clientHeight
    }
};

$.fn.center = function(option, callback) {
    var settings = $.extend({}, option)
    var position = settings.position || 'fixed'
    var $win = $(win)

    function fixIE6($el) {
        $el[0].style.position = 'absolute'
        $win.scroll(function() {
            move($el)
        })
    }
    function move($that) {
        var that = $that[0]
        var size = $.viewSize()
        var x = (size.width)/2 - (that.clientWidth)/2
        var y = (size.height)/2 - (that.clientHeight)/2
        if ($.ie6) {
            var scrollTop = docElem.scrollTop || document.body.scrollTop
            y += scrollTop
        }
        $that.css({
            top: y + px,
            left: x + px
        })
    }
    function init($that, option) {
        $that.css({
            position: position
        }).show()
        // ie6 don't support position 'fixed'
        if (position === 'fixed' && $.ie6) {
            fixIE6($that)
        }
        move($that)
    }

    return this.each(function() {
        var $that = $(this)
        init($that, option)
        if (callback) callback($that)
    })
};

$.uiParse = function(action) {
    var arr = action.split('|').slice(1)
    var len = arr.length
    var res = [], exs
    var boo = /^(true|false)$/
    for (var i = 0; i < len; i++) {
        var item = arr[i]
        if (item == '&') {
            item = undefined
        } else if (exs = item.match(boo)) {
            item = exs[0] == 'true' ? true : false
        }
        res[i] = item
    }
    return res
};

}(window, window.jQuery);

/**
 * PlaceHolder组件
 * $(input).focusPic({
 *   word:     // @string 提示文本
 *   color:    // @string 文本颜色
 *   evtType:  // @string focus|keydown 触发placeholder的事件类型
 *   zIndex:   // 模拟placeholder的zIndex
 *   diffPaddingLeft: 距离左侧的left，光标位置可调，默认取输入域的paddingLeft+3
 * })
 *
 * NOTE：
 *   evtType默认是focus，即鼠标点击到输入域时默认文本消失，keydown则模拟HTML5 placeholder属性在Firefox/Chrome里的特征，光标定位到输入域后键盘输入时默认文本才消失。
 *   此外，对于HTML5 placeholder属性，IE10+和Firefox/Chrome/Safari的表现形式也不一致，因此内部实现不采用原生placeholder属性
 */

~function() {
	
$.fn.placeholder = function(option, callback) {
	var settings = $.extend({
		word: '',
		color: '#999',
		evtType: 'focus',
		zIndex: 20,
		diffPaddingLeft: 3
	}, option)

	function bootstrap($that) {
		// some alias 
		var word    = settings.word
		var color   = settings.color
		var evtType = settings.evtType
		var zIndex  = settings.zIndex
		var diffPaddingLeft = settings.diffPaddingLeft

		// default css
		var width       = $that.outerWidth()
		var height      = $that.outerHeight()
		var fontSize    = $that.css('font-size')
		var fontFamily  = $that.css('font-family')
		var paddingLeft = $that.css('padding-left')

		// process
		var thatid = $that.attr("id");
		paddingLeft = parseInt(paddingLeft, 10) + diffPaddingLeft

		// redner 
		var $placeholder = jQuery("#placeholder"+thatid);
		if($placeholder.size()==0) {
			$placeholder = $('<span class="placeholder" id="placeholder'+thatid+'">')
		}
		$placeholder.css({
			position: 'absolute',
			zIndex: '20',
			color: color,
			width: (width - paddingLeft) + 'px',
			height: height + 'px',
			fontSize: fontSize,
			paddingLeft: paddingLeft + 'px',
			fontFamily: fontFamily
		}).text(word).hide()

		// 位置调整 
		move()

		// textarea 不加line-heihgt属性
		if ($that.is('input')) {
			$placeholder.css({
				lineHeight: height + 'px'
			})
		}
		//$placeholder.appendTo(document.body)
		$that.after($placeholder);

		// 内容为空时才显示，比如刷新页面输入域已经填入了内容时
		var val = $that.val()
		if ( val == '' && $that.is(':visible') ) {
			$placeholder.show()
		} else {
			jQuery("#placeholder"+thatid).remove();
		}

        function hideAndFocus() {
            $placeholder.hide()
            $that[0].focus()
        }
        function move() {
            var offset = $that.offset()
            var top    = offset.top
            var left   = offset.left
            $placeholder.css({
                top: top,
                left: left
            })
        }
		function asFocus() {
			$placeholder.click(function() {
				hideAndFocus()
				// 盖住后无法触发input的click事件，需要模拟点击下
                setTimeout(function(){
                    $that.click()
                }, 100)
			})
            // IE有些bug，原本不用加此句
            $that.click(hideAndFocus)
			$that.blur(function() {
				var txt = $that.val()
				if (txt == '') {
					$placeholder.show()
				}
			})
		}
		function asKeydown() {
			$placeholder.click(function() {
				$that[0].focus()
			})
		}
		if (evtType == 'focus') {
			asFocus()
		} else if (evtType == 'keydown') {
			asKeydown()
		} else {
		}

		$that.keyup(function() {
			var txt = $that.val()
			var isFocus=$that.is(":focus");
			if (txt == '' && !isFocus) {
				$placeholder.show()
			} else {
				$placeholder.hide()
			}
		})

        // 窗口缩放时处理
        $(window).resize(function() {
        	move()
        })

        // cache
        $that.data('el', $placeholder)
        $that.data('move', move)

	}

	return this.each(function() {
		var $elem = $(this)
		bootstrap($elem)
		if ($.isFunction(callback)) callback($elem)
	})
}	


/*
 * 自动初始化，配置参数按照使用频率先后排序，即最经常使用的在前，不经常使用的往后，使用默认参数替代
 * 
 * 格式：data-ui="u-placeholder|word|evtType|color
 * 示例：data-ui="u-placeholder|默认文字
 *
 */
$(function() {
    $('[data-ui^="u-placeholder"]').each(function() {
    	doPlaceholder(this)
    })
})

}();