var imf = function () {
	var lf = 0;
	var instances = [];
	function getelementsbyclass (object, tag, classname) {
		var o = object.getelementsbytagname(tag);
		for ( var i = 0, n = o.length, ret = []; i < n; i++)
			if (o[i].classname == classname) ret.push(o[i]);
		if (ret.length == 1) ret = ret[0];
		return ret;
	}
	function addevent (o, e, f) {
		if (window.addeventlistener) o.addeventlistener(e, f, false);
		else if (window.attachevent) r = o.attachevent('on' + e, f);
	}
	function createreflexion (cont, img) {
		var flx = false;
		if (document.createelement("canvas").getcontext) {
			flx = document.createelement("canvas");
			flx.width = img.width;
            flx.height = img.height;
			var context = flx.getcontext("2d");
			context.translate(0, img.height);
			context.scale(1, 0);//倒影的方向和明度（1，-1）
			context.drawimage(img, 0, 0, img.width, img.height);
			context.globalcompositeoperation = "destination-out";
			var gradient = context.createlineargradient(0, 0, 0, img.height * 2);
			gradient.addcolorstop(1, "rgba(255, 255, 255, 0)");
			gradient.addcolorstop(0, "rgba(255, 255, 255, 1)");
			context.fillstyle = gradient;
			context.fillrect(0, 0, img.width, img.height * 2);
		} else {
			/* ---- dximagetransform ---- */
			flx     = document.createelement('img');
			flx.src = img.src;
			flx.style.filter = 'flipv progid:dximagetransform.microsoft.alpha(' +
			                   'opacity=50, style=1, finishopacity=0, startx=0, starty=0, finishx=0, finishy=' +
							   (img.height * .25) + ')';
		}
		/* ---- insert reflexion ---- */
		flx.style.position = 'absolute';
		flx.style.left     = '-1000px';
		cont.appendchild(flx);
		return flx;
	}
	/* //////////// ==== imageflow constructor ==== //////////// */
	function imageflow(ocont, size, zoom, border) {
		this.diapos     = [];
		this.scr        = false;
		this.size       = size;
		this.zoom       = zoom;
		this.bdw        = border;
		this.ocont      = ocont;
		this.oc         = document.getelementbyid(ocont);
		this.scrollbar  = getelementsbyclass(this.oc,   'div', 'scrollbar');
		this.text       = getelementsbyclass(this.oc,   'div', 'text');
		this.title      = getelementsbyclass(this.text, 'div', 'title');
		this.legend     = getelementsbyclass(this.text, 'div', 'legend');
		this.bar        = getelementsbyclass(this.oc,   'img', 'bar');
		this.arl        = getelementsbyclass(this.oc,   'img', 'arrow-left');
		this.arr        = getelementsbyclass(this.oc,   'img', 'arrow-right');
		this.bw         = this.bar.width;
		this.alw        = this.arl.width - 5;
		this.arw        = this.arr.width - 5;
		this.bar.parent = this.oc.parent  = this;
		this.arl.parent = this.arr.parent = this;
		this.view       = this.back       = -1;
		this.resize();
		this.oc.onselectstart = function () { return false; }
		/* ---- create images ---- */
		var img   = getelementsbyclass(this.oc, 'div', 'bank').getelementsbytagname('a');
		this.nf = img.length;
		for (var i = 0, o; o = img[i]; i++) {
			this.diapos[i] = new diapo(this, i,
										o.rel,
										o.title || '- ' + i + ' -',
										o.innerhtml || o.rel,
										o.href || '',
										o.target || '_self'
			);
		}
		/* ==== add mouse wheel events ==== */
		if (window.addeventlistener)
			this.oc.addeventlistener('dommousescroll', function(e) {
				this.parent.scroll(-e.detail);
			}, false);
		else this.oc.onmousewheel = function () {
			this.parent.scroll(event.wheeldelta);
		}
		/* ==== scrollbar drag n drop ==== */
		this.bar.onmousedown = function (e) {
			if (!e) e = window.event;
			var scl = e.screenx - this.offsetleft;
			var self = this.parent;
			/* ---- move bar ---- */
			this.parent.oc.onmousemove = function (e) {
				if (!e) e = window.event;
				self.bar.style.left = math.round(math.min((self.ws - self.arw - self.bw), math.max(self.alw, e.screenx - scl))) + 'px';
				self.view = math.round(((e.screenx - scl) ) / (self.ws - self.alw - self.arw - self.bw) * self.nf);
				if (self.view != self.back) self.calc();
				return false;
			}
			/* ---- release scrollbar ---- */
			this.parent.oc.onmouseup = function (e) {
				self.oc.onmousemove = null;
				return false;
			}
			return false;
		}
		/* ==== right arrow ==== */
		this.arr.onclick = this.arr.ondblclick = function () {
			if (this.parent.view < this.parent.nf - 1)
				this.parent.calc(1);
		}
		/* ==== left arrow ==== */
		this.arl.onclick = this.arl.ondblclick = function () {
			if (this.parent.view > 0)
				this.parent.calc(-1);
		}
	}
	/* //////////// ==== imageflow prototype ==== //////////// */
	imageflow.prototype = {
		/* ==== targets ==== */
		calc : function (inc) {
			if (inc) this.view += inc;
			var tw = 0;
			var lw = 0;
			var o = this.diapos[this.view];
			if (o && o.loaded) {
				/* ---- reset ---- */
				var ob = this.diapos[this.back];
				if (ob && ob != o) {
					ob.img.classname = 'diapo';
					ob.z1 = 1;
				}
				/* ---- update legend ---- */
				this.title.replacechild(document.createtextnode(o.title), this.title.firstchild);
				this.legend.replacechild(document.createtextnode(o.text), this.legend.firstchild);
				/* ---- update hyperlink ---- */
				if (o.url) {
					o.img.classname = 'diapo link';
					window.status = 'hyperlink: ' + o.url;
				} else {
					o.img.classname = 'diapo';
					window.status = '';
				}
				/* ---- calculate target sizes & positions ---- */
				o.w1 = math.min(o.iw, this.wh * .5) * o.z1;
				var x0 = o.x1 = (this.wh * .5) - (o.w1 * .5);
				var x = x0 + o.w1 + this.bdw;
				for (var i = this.view + 1, o; o = this.diapos[i]; i++) {
					if (o.loaded) {
						o.x1 = x;
						o.w1 = (this.ht / o.r) * this.size;
						x   += o.w1 + this.bdw;
						tw  += o.w1 + this.bdw;
					}
				}
				x = x0 - this.bdw;
				for (var i = this.view - 1, o; o = this.diapos[i]; i--) {
					if (o.loaded) {
						o.w1 = (this.ht / o.r) * this.size;
						o.x1 = x - o.w1;
						x   -= o.w1 + this.bdw;
						tw  += o.w1 + this.bdw;
						lw  += o.w1 + this.bdw;
					}
				}
				/* ---- move scrollbar ---- */
				if (!this.scr && tw) {
					var r = (this.ws - this.alw - this.arw - this.bw) / tw;
					this.bar.style.left = math.round(this.alw + lw * r) + 'px';
				}
				/* ---- save preview view ---- */
				this.back = this.view;
			}
		},
		/* ==== mousewheel scrolling ==== */
		scroll : function (sc) {
			if (sc < 0) {
				if (this.view < this.nf - 1) this.calc(1);
			} else {
				if (this.view > 0) this.calc(-1);
			}
		},
		/* ==== resize  ==== */
		resize : function () {
			this.wh = this.oc.clientwidth;
			this.ht = this.oc.clientheight;
			this.ws = this.scrollbar.offsetwidth;
			this.calc();
			this.run(true);
		},
		/* ==== move all images  ==== */
		run : function (res) {
			var i = this.nf;
			while (i--) this.diapos[i].move(res);
		}
	}
	/* //////////// ==== diapo constructor ==== //////////// */
	diapo = function (parent, n, src, title, text, url, target) {
		this.parent        = parent;
		this.loaded        = false;
		this.title         = title;
		this.text          = text;
		this.url           = url;
		this.target        = target;
		this.n             = n;
		this.img           = document.createelement('img');
		this.img.src       = src;
		this.img.parent    = this;
		this.img.classname = 'diapo';
		this.x0            = this.parent.oc.clientwidth;
		this.x1            = this.x0;
		this.w0            = 0;
		this.w1            = 0;
		this.z1            = 1;
		this.img.parent    = this;
		this.img.onclick   = function() { this.parent.click(); }
		this.parent.oc.appendchild(this.img);
		/* ---- display external link ---- */
		if (url) {
			this.img.onmouseover = function () { this.classname = 'diapo link';	}
			this.img.onmouseout  = function () { this.classname = 'diapo'; }
		}
	}
	/* //////////// ==== diapo prototype ==== //////////// */
	diapo.prototype = {
		/* ==== html rendering ==== */
		move : function (res) {
			if (this.loaded) {
				var sx = this.x1 - this.x0;
				var sw = this.w1 - this.w0;
				if (math.abs(sx) > 2 || math.abs(sw) > 2 || res) {
					/* ---- paint only when moving ---- */
					this.x0 += sx * .1;
					this.w0 += sw * .1;
					if (this.x0 < this.parent.wh && this.x0 + this.w0 > 0) {
						/* ---- paint only visible images ---- */
						this.visible = true;
						var o = this.img.style;
						var h = this.w0 * this.r;
						/* ---- diapo ---- */
						o.left   = math.round(this.x0) + 'px';
						o.bottom = math.floor(this.parent.ht * .25) + 'px';
						o.width  = math.round(this.w0) + 'px';
						o.height = math.round(h) + 'px';
						/* ---- reflexion ---- */
						if (this.flx) {
							var o = this.flx.style;
							o.left   = math.round(this.x0) + 'px';
							o.top    = math.ceil(this.parent.ht * .75 + 1) + 'px';
							o.width  = math.round(this.w0) + 'px';
							o.height = math.round(h) + 'px';
						}
					} else {
						/* ---- disable invisible images ---- */
						if (this.visible) {
							this.visible = false;
							this.img.style.width = '0px';
							if (this.flx) this.flx.style.width = '0px';
						}
					}
				}
			} else {
				/* ==== image onload ==== */
				if (this.img.complete && this.img.width) {
					/* ---- get size image ---- */
					this.iw     = this.img.width;
					this.ih     = this.img.height;
					this.r      = this.ih / this.iw;
					this.loaded = true;
					/* ---- create reflexion ---- */
					this.flx    = createreflexion(this.parent.oc, this.img);
					if (this.parent.view < 0) this.parent.view = this.n;
					this.parent.calc();
				}
			}
		},
		/* ==== diapo onclick ==== */
		click : function () {
			if (this.parent.view == this.n) {
				/* ---- click on zoomed diapo ---- */
				if (this.url) {
					/* ---- open hyperlink ---- */
					window.open(this.url, this.target);
				} else {
					/* ---- zoom in/out ---- */
					this.z1 = this.z1 == 1 ? this.parent.zoom : 1;
					this.parent.calc();
				}
			} else {
				/* ---- select diapo ---- */
				this.parent.view = this.n;
				this.parent.calc();
			}
			return false;
		}
	}
	/* //////////// ==== public methods ==== //////////// */
	return {
		/* ==== initialize script ==== */
		create : function (div, size, zoom, border) {
			/* ---- instanciate imageflow ---- */
			var load = function () {
				var loaded = false;
				var i = instances.length;
				while (i--) if (instances[i].ocont == div) loaded = true;
				if (!loaded) {
					/* ---- push new imageflow instance ---- */
					instances.push(
						new imageflow(div, size, zoom, border)
					);
					/* ---- init script (once) ---- */
					if (!imf.initialized) {
						imf.initialized = true;
						/* ---- window resize event ---- */
						addevent(window, 'resize', function () {
							var i = instances.length;
							while (i--) instances[i].resize();
						});
						/* ---- stop drag n drop ---- */
						addevent(document.getelementbyid(div), 'mouseout', function (e) {
							if (!e) e = window.event;
							var tg = e.relatedtarget || e.toelement;
							if (tg && tg.tagname == 'html') {
								var i = instances.length;
								while (i--) instances[i].oc.onmousemove = null;
							}
							return false;
						});
						/* ---- set interval loop ---- */
						setinterval(function () {
							var i = instances.length;
							while (i--) instances[i].run();
						}, 16);
					}
				}
			}
			/* ---- window onload event ---- */
			addevent(window, 'load', function () { load(); });
		}
	}
}();

/* ==== create imageflow ==== */
//          div id    , size, zoom, border
imf.create("imageflow", 0.42, 1.18, 10);