Remove a lot of CSS cruft, touch on #144

[deck.js.git] / core / deck.core.js

/*!
Deck JS - deck.core
Copyright (c) 2011 Caleb Troughton
Dual licensed under the MIT license and GPL license.
https://github.com/imakewebthings/deck.js/blob/master/MIT-license.txt
https://github.com/imakewebthings/deck.js/blob/master/GPL-license.txt
*/

/*
The deck.core module provides all the basic functionality for creating and
moving through a deck.  It does so by applying classes to indicate the state of
the deck and its slides, allowing CSS to take care of the visual representation
of each state.  It also provides methods for navigating the deck and inspecting
its state, as well as basic key bindings for going to the next and previous
slides.  More functionality is provided by wholly separate extension modules
that use the API provided by core.
*/
(function($, deck, document, undefined) {
        var slides, // Array of all the uh, slides...
        current, // Array index of the current slide
        $container, // Keeping this cached

        events = {
                /*
                This event fires at the beginning of a slide change, before the actual
                change occurs. Its purpose is to give extension authors a way to prevent
                the slide change from occuring. This is done by calling preventDefault
                on the event object within this event. If that is done, the deck.change
                event will never be fired and the slide will not change.
                */
                beforeChange: 'deck.beforeChange',

                /*
                This event fires whenever the current slide changes, whether by way of
                next, prev, or go. The callback function is passed two parameters, from
                and to, equal to the indices of the old slide and the new slide
                respectively. If preventDefault is called on the event within this handler
                the slide change does not occur.

                $(document).bind('deck.change', function(event, from, to) {
                   alert('Moving from slide ' + from + ' to ' + to);
                });
                */
                change: 'deck.change',

                /*
                This event fires at the beginning of deck initialization, after the options
                are set but before the slides array is created.  This event makes a good hook
                for preprocessing extensions looking to modify the deck.
                */
                beforeInitialize: 'deck.beforeInit',

                /*
                This event fires at the end of deck initialization. Extensions should
                implement any code that relies on user extensible options (key bindings,
                element selectors, classes) within a handler for this event. Native
                events associated with Deck JS should be scoped under a .deck event
                namespace, as with the example below:

                var $d = $(document);
                $.deck.defaults.keys.myExtensionKeycode = 70; // 'h'
                $d.bind('deck.init', function() {
                   $d.bind('keydown.deck', function(event) {
                      if (event.which === $.deck.getOptions().keys.myExtensionKeycode) {
                         // Rock out
                      }
                   });
                });
                */
                initialize: 'deck.init'
        },

        options = {},
        $d = $(document),

        /*
        Internal function. Updates slide and container classes based on which
        slide is the current slide.
        */
        updateStates = function() {
                var oc = options.classes,
                osc = options.selectors.container,
                old = $container.data('onSlide'),
                $all = $();

                // Container state
                $container.removeClass(oc.onPrefix + old)
                        .addClass(oc.onPrefix + current)
                        .data('onSlide', current);

                // Remove and re-add child-current classes for nesting
                $('.' + oc.current).parentsUntil(osc).removeClass(oc.childCurrent);
                slides[current].parentsUntil(osc).addClass(oc.childCurrent);

                // Remove previous states
                $.each(slides, function(i, el) {
                        $all = $all.add(el);
                });
                $all.removeClass([
                        oc.before,
                        oc.previous,
                        oc.current,
                        oc.next,
                        oc.after
                ].join(" "));

                // Add new states back in
                slides[current].addClass(oc.current);
                if (current > 0) {
                        slides[current-1].addClass(oc.previous);
                }
                if (current + 1 < slides.length) {
                        slides[current+1].addClass(oc.next);
                }
                if (current > 1) {
                        $.each(slides.slice(0, current - 1), function(i, el) {
                                el.addClass(oc.before);
                        });
                }
                if (current + 2 < slides.length) {
                        $.each(slides.slice(current+2), function(i, el) {
                                el.addClass(oc.after);
                        });
                }
        },

        /* Methods exposed in the jQuery.deck namespace */
        methods = {

                /*
                jQuery.deck(selector, options)

                selector: string | jQuery | array
                options: object, optional

                Initializes the deck, using each element matched by selector as a slide.
                May also be passed an array of string selectors or jQuery objects, in
                which case each selector in the array is considered a slide. The second
                parameter is an optional options object which will extend the default
                values.

                $.deck('.slide');

                or

                $.deck([
                   '#first-slide',
                   '#second-slide',
                   '#etc'
                ]);
                */
                init: function(elements, opts) {
                        var startTouch,
                        tolerance,
                        esp = function(e) {
                                e.stopPropagation();
                        };

                        options = $.extend(true, {}, $[deck].defaults, opts);
                        slides = [];
                        current = 0;
                        $container = $(options.selectors.container);
                        tolerance = options.touch.swipeTolerance;

                        // Pre init event for preprocessing hooks
                        $d.trigger(events.beforeInitialize);

                        // Hide the deck while states are being applied to kill transitions
                        $container.addClass(options.classes.loading);

                        // Fill slides array depending on parameter type
                        if ($.isArray(elements)) {
                                $.each(elements, function(i, e) {
                                        slides.push($(e));
                                });
                        }
                        else {
                                $(elements).each(function(i, e) {
                                        slides.push($(e));
                                });
                        }

                        /* Remove any previous bindings, and rebind key events */
                        $d.unbind('keydown.deck').bind('keydown.deck', function(e) {
                                if (e.which === options.keys.next || $.inArray(e.which, options.keys.next) > -1) {
                                        methods.next();
                                        e.preventDefault();
                                }
                                else if (e.which === options.keys.previous || $.inArray(e.which, options.keys.previous) > -1) {
                                        methods.prev();
                                        e.preventDefault();
                                }
                        })
                        /* Stop propagation of key events within editable elements */
                        .undelegate('input, textarea, select, button, meter, progress, [contentEditable]', 'keydown', esp)
                        .delegate('input, textarea, select, button, meter, progress, [contentEditable]', 'keydown', esp);

                        /* Bind touch events for swiping between slides on touch devices */
                        $container.unbind('touchstart.deck').bind('touchstart.deck', function(e) {
                                if (!startTouch) {
                                        startTouch = $.extend({}, e.originalEvent.targetTouches[0]);
                                }
                        })
                        .unbind('touchmove.deck').bind('touchmove.deck', function(e) {
                                $.each(e.originalEvent.changedTouches, function(i, t) {
                                        if (startTouch && t.identifier === startTouch.identifier) {
                                                if (t.screenX - startTouch.screenX > tolerance || t.screenY - startTouch.screenY > tolerance) {
                                                        $[deck]('prev');
                                                        startTouch = undefined;
                                                }
                                                else if (t.screenX - startTouch.screenX < -1 * tolerance || t.screenY - startTouch.screenY < -1 * tolerance) {
                                                        $[deck]('next');
                                                        startTouch = undefined;
                                                }
                                                return false;
                                        }
                                });
                                e.preventDefault();
                        })
                        .unbind('touchend.deck').bind('touchend.deck', function(t) {
                                $.each(t.originalEvent.changedTouches, function(i, t) {
                                        if (startTouch && t.identifier === startTouch.identifier) {
                                                startTouch = undefined;
                                        }
                                });
                        })
                        .scrollLeft(0).scrollTop(0);

                        /*
                        Kick iframe videos, which dont like to redraw w/ transforms.
                        Remove this if Webkit ever fixes it.
                         */
                        $.each(slides, function(i, $el) {
                                $el.unbind('webkitTransitionEnd.deck').bind('webkitTransitionEnd.deck',
                                function(event) {
                                        if ($el.hasClass($[deck]('getOptions').classes.current)) {
                                                var embeds = $(this).find('iframe').css('opacity', 0);
                                                window.setTimeout(function() {
                                                        embeds.css('opacity', 1);
                                                }, 100);
                                        }
                                });
                        });

                        if (slides.length) {
                                updateStates();
                        }

                        // Show deck again now that slides are in place
                        $container.removeClass(options.classes.loading);
                        $d.trigger(events.initialize);
                },

                /*
                jQuery.deck('go', index)

                index: integer | string

                Moves to the slide at the specified index if index is a number. Index is
                0-based, so $.deck('go', 0); will move to the first slide. If index is a
                string this will move to the slide with the specified id. If index is out
                of bounds or doesn't match a slide id the call is ignored.
                */
                go: function(index) {
                        var e = $.Event(events.beforeChange),
                        ndx;

                        /* Number index, easy. */
                        if (typeof index === 'number' && index >= 0 && index < slides.length) {
                                ndx = index;
                        }
                        /* Id string index, search for it and set integer index */
                        else if (typeof index === 'string') {
                                $.each(slides, function(i, $slide) {
                                        if ($slide.attr('id') === index) {
                                                ndx = i;
                                                return false;
                                        }
                                });
                        };

                        /* Out of bounds, id doesn't exist, illegal input, eject */
                        if (typeof ndx === 'undefined') return;

                        /* Trigger beforeChange. If nothing prevents the change, trigger
                        the slide change. */
                        $d.trigger(e, [current, ndx]);
                        if (!e.isDefaultPrevented()) {
                                $d.trigger(events.change, [current, ndx]);
                                current = ndx;
                                updateStates();
                        }
                },

                /*
                jQuery.deck('next')

                Moves to the next slide. If the last slide is already active, the call
                is ignored.
                */
                next: function() {
                        methods.go(current+1);
                },

                /*
                jQuery.deck('prev')

                Moves to the previous slide. If the first slide is already active, the
                call is ignored.
                */
                prev: function() {
                        methods.go(current-1);
                },

                /*
                jQuery.deck('getSlide', index)

                index: integer, optional

                Returns a jQuery object containing the slide at index. If index is not
                specified, the current slide is returned.
                */
                getSlide: function(index) {
                        var i = typeof index !== 'undefined' ? index : current;
                        if (typeof i != 'number' || i < 0 || i >= slides.length) return null;
                        return slides[i];
                },

                /*
                jQuery.deck('getSlides')

                Returns all slides as an array of jQuery objects.
                */
                getSlides: function() {
                        return slides;
                },

                /*
                jQuery.deck('getContainer')

                Returns a jQuery object containing the deck container as defined by the
                container option.
                */
                getContainer: function() {
                        return $container;
                },

                /*
                jQuery.deck('getOptions')

                Returns the options object for the deck, including any overrides that
                were defined at initialization.
                */
                getOptions: function() {
                        return options;
                },

                /*
                jQuery.deck('extend', name, method)

                name: string
                method: function

                Adds method to the deck namespace with the key of name. This doesn’t
                give access to any private member data — public methods must still be
                used within method — but lets extension authors piggyback on the deck
                namespace rather than pollute jQuery.

                $.deck('extend', 'alert', function(msg) {
                   alert(msg);
                });

                // Alerts 'boom'
                $.deck('alert', 'boom');
                */
                extend: function(name, method) {
                        methods[name] = method;
                }
        };

        /* jQuery extension */
        $[deck] = function(method, arg) {
                if (methods[method]) {
                        return methods[method].apply(this, Array.prototype.slice.call(arguments, 1));
                }
                else {
                        return methods.init(method, arg);
                }
        };

        /*
        The default settings object for a deck. All deck extensions should extend
        this object to add defaults for any of their options.

        options.classes.after
                This class is added to all slides that appear after the 'next' slide.

        options.classes.before
                This class is added to all slides that appear before the 'previous'
                slide.

        options.classes.childCurrent
                This class is added to all elements in the DOM tree between the
                'current' slide and the deck container. For standard slides, this is
                mostly seen and used for nested slides.

        options.classes.current
                This class is added to the current slide.

        options.classes.loading
                This class is applied to the deck container during loading phases and is
                primarily used as a way to short circuit transitions between states
                where such transitions are distracting or unwanted.  For example, this
                class is applied during deck initialization and then removed to prevent
                all the slides from appearing stacked and transitioning into place
                on load.

        options.classes.next
                This class is added to the slide immediately following the 'current'
                slide.

        options.classes.onPrefix
                This prefix, concatenated with the current slide index, is added to the
                deck container as you change slides.

        options.classes.previous
                This class is added to the slide immediately preceding the 'current'
                slide.

        options.selectors.container
                Elements matched by this CSS selector will be considered the deck
                container. The deck container is used to scope certain states of the
                deck, as with the onPrefix option, or with extensions such as deck.goto
                and deck.menu.

        options.keys.next
                The numeric keycode used to go to the next slide.

        options.keys.previous
                The numeric keycode used to go to the previous slide.

        options.touch.swipeTolerance
                The number of pixels the users finger must travel to produce a swipe
                gesture.
        */
        $[deck].defaults = {
                classes: {
                        after: 'deck-after',
                        before: 'deck-before',
                        childCurrent: 'deck-child-current',
                        current: 'deck-current',
                        loading: 'deck-loading',
                        next: 'deck-next',
                        onPrefix: 'on-slide-',
                        previous: 'deck-previous'
                },

                selectors: {
                        container: '.deck-container'
                },

                keys: {
                        // enter, space, page down, right arrow, down arrow,
                        next: [13, 32, 34, 39, 40],
                        // backspace, page up, left arrow, up arrow
                        previous: [8, 33, 37, 38]
                },

                touch: {
                        swipeTolerance: 60
                }
        };

        $d.ready(function() {
                $('html').addClass('ready');
        });
})(jQuery, 'deck', document);