/**
* author Remy Sharp
* url http://remysharp.com/tag/marquee
*/
(function ($) {
$.fn.marquee = function (klass) {
var newMarquee = [],
last = this.length;
// works out the left or right hand reset position, based on scroll
// behavior, current direction and new direction
function getReset(newDir, marqueeRedux, marqueeState) {
var behavior = marqueeState.behavior, width = marqueeState.width, dir = marqueeState.dir;
var r = 0;
if (behavior == 'alternate') {
r = newDir == 1 ? marqueeRedux[marqueeState.widthAxis] - (width*2) : width;
} else if (behavior == 'slide') {
if (newDir == -1) {
r = dir == -1 ? marqueeRedux[marqueeState.widthAxis] : width;
} else {
r = dir == -1 ? marqueeRedux[marqueeState.widthAxis] - (width*2) : 0;
}
} else {
r = newDir == -1 ? marqueeRedux[marqueeState.widthAxis] : 0;
}
return r;
}
// single "thread" animation
function animateMarquee() {
var i = newMarquee.length,
marqueeRedux = null,
$marqueeRedux = null,
marqueeState = {},
newMarqueeList = [],
hitedge = false;
while (i--) {
marqueeRedux = newMarquee[i];
$marqueeRedux = $(marqueeRedux);
marqueeState = $marqueeRedux.data('marqueeState');
if ($marqueeRedux.data('paused') !== true) {
// TODO read scrollamount, dir, behavior, loops and last from data
marqueeRedux[marqueeState.axis] += (marqueeState.scrollamount * marqueeState.dir);
// only true if it's hit the end
hitedge = marqueeState.dir == -1 ? marqueeRedux[marqueeState.axis] <= getReset(marqueeState.dir * -1, marqueeRedux, marqueeState) : marqueeRedux[marqueeState.axis] >= getReset(marqueeState.dir * -1, marqueeRedux, marqueeState);
if ((marqueeState.behavior == 'scroll' && marqueeState.last == marqueeRedux[marqueeState.axis]) || (marqueeState.behavior == 'alternate' && hitedge && marqueeState.last != -1) || (marqueeState.behavior == 'slide' && hitedge && marqueeState.last != -1)) {
if (marqueeState.behavior == 'alternate') {
marqueeState.dir *= -1; // flip
}
marqueeState.last = -1;
$marqueeRedux.trigger('stop');
marqueeState.loops--;
if (marqueeState.loops === 0) {
if (marqueeState.behavior != 'slide') {
marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
} else {
// corrects the position
marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir * -1, marqueeRedux, marqueeState);
}
$marqueeRedux.trigger('end');
} else {
// keep this marquee going
newMarqueeList.push(marqueeRedux);
$marqueeRedux.trigger('start');
marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
}
} else {
newMarqueeList.push(marqueeRedux);
}
marqueeState.last = marqueeRedux[marqueeState.axis];
// store updated state only if we ran an animation
$marqueeRedux.data('marqueeState', marqueeState);
} else {
// even though it's paused, keep it in the list
newMarqueeList.push(marqueeRedux);
}
}
newMarquee = newMarqueeList;
if (newMarquee.length) {
setTimeout(animateMarquee, 25);
}
}
// TODO consider whether using .html() in the wrapping process could lead to loosing predefined events...
this.each(function (i) {
var $marquee = $(this),
width = $marquee.attr('width') || $marquee.width(),
height = $marquee.attr('height') || $marquee.height(),
$marqueeRedux = $marquee.after('<div ' + (klass ? 'class="' + klass + '" ' : '') + 'style="display: block-inline; width: ' + width + 'px; height: ' + height + 'px; overflow: hidden;"><div style="float: left; white-space: nowrap;">' + $marquee.html() + '</div></div>').next(),
marqueeRedux = $marqueeRedux.get(0),
hitedge = 0,
direction = ($marquee.attr('direction') || 'left').toLowerCase(),
marqueeState = {
dir : /down|right/.test(direction) ? -1 : 1,
axis : /left|right/.test(direction) ? 'scrollLeft' : 'scrollTop',
widthAxis : /left|right/.test(direction) ? 'scrollWidth' : 'scrollHeight',
last : -1,
loops : $marquee.attr('loop') || -1,
scrollamount : $marquee.attr('scrollamount') || this.scrollAmount || 2,
behavior : ($marquee.attr('behavior') || 'scroll').toLowerCase(),
width : /left|right/.test(direction) ? width : height
};
// corrects a bug in Firefox - the default loops for slide is -1
if ($marquee.attr('loop') == -1 && marqueeState.behavior == 'slide') {
marqueeState.loops = 1;
}
$marquee.remove();
// add padding
if (/left|right/.test(direction)) {
$marqueeRedux.find('> div').css('padding', '0 ' + width + 'px');
} else {
$marqueeRedux.find('> div').css('padding', height + 'px 0');
}
// events
$marqueeRedux.bind('stop', function () {
$marqueeRedux.data('paused', true);
}).bind('pause', function () {
$marqueeRedux.data('paused', true);
}).bind('start', function () {
$marqueeRedux.data('paused', false);
}).bind('unpause', function () {
$marqueeRedux.data('paused', false);
}).data('marqueeState', marqueeState); // finally: store the state
// todo - rerender event allowing us to do an ajax hit and redraw the marquee
newMarquee.push(marqueeRedux);
marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
$marqueeRedux.trigger('start');
// on the very last marquee, trigger the animation
if (i+1 == last) {
animateMarquee();
}
});
return $(newMarquee);
};
}(jQuery));
