/**
*
* history.js:
*
* - Back button to close gallery.
*
* - Unique URL for each slide: example.com/&pid=1&gid=3
* (where PID is picture index, and GID and gallery index)
*
* - Switch URL when slides change.
*
*/
var _historyDefaultOptions = {
history: true,
galleryUID: 1
};
var _historyUpdateTimeout,
_hashChangeTimeout,
_hashAnimCheckTimeout,
_hashChangedByScript,
_hashChangedByHistory,
_hashReseted,
_initialHash,
_historyChanged,
_closedFromURL,
_urlChangedOnce,
_windowLoc,
_supportsPushState,
_getHash = function() {
return _windowLoc.hash.substring(1);
},
_cleanHistoryTimeouts = function() {
if(_historyUpdateTimeout) {
clearTimeout(_historyUpdateTimeout);
}
if(_hashAnimCheckTimeout) {
clearTimeout(_hashAnimCheckTimeout);
}
},
// pid - Picture index
// gid - Gallery index
_parseItemIndexFromURL = function() {
var hash = _getHash(),
params = {};
if(hash.length < 5) { // pid=1
return params;
}
var i, vars = hash.split('&');
for (i = 0; i < vars.length; i++) {
if(!vars[i]) {
continue;
}
var pair = vars[i].split('=');
if(pair.length < 2) {
continue;
}
params[pair[0]] = pair[1];
}
if(_options.galleryPIDs) {
// detect custom pid in hash and search for it among the items collection
var searchfor = params.pid;
params.pid = 0; // if custom pid cannot be found, fallback to the first item
for(i = 0; i < _items.length; i++) {
if(_items[i].pid === searchfor) {
params.pid = i;
break;
}
}
} else {
params.pid = parseInt(params.pid,10)-1;
}
if( params.pid < 0 ) {
params.pid = 0;
}
return params;
},
_updateHash = function() {
if(_hashAnimCheckTimeout) {
clearTimeout(_hashAnimCheckTimeout);
}
if(_numAnimations || _isDragging) {
// changing browser URL forces layout/paint in some browsers, which causes noticable lag during animation
// that's why we update hash only when no animations running
_hashAnimCheckTimeout = setTimeout(_updateHash, 500);
return;
}
if(_hashChangedByScript) {
clearTimeout(_hashChangeTimeout);
} else {
_hashChangedByScript = true;
}
var pid = (_currentItemIndex + 1);
var item = _getItemAt( _currentItemIndex );
if(item.hasOwnProperty('pid')) {
// carry forward any custom pid assigned to the item
pid = item.pid;
}
var newHash = _initialHash + '&' + 'gid=' + _options.galleryUID + '&' + 'pid=' + pid;
if(!_historyChanged) {
if(_windowLoc.hash.indexOf(newHash) === -1) {
_urlChangedOnce = true;
}
// first time - add new hisory record, then just replace
}
var newURL = _windowLoc.href.split('#')[0] + '#' + newHash;
if( _supportsPushState ) {
if('#' + newHash !== window.location.hash) {
history[_historyChanged ? 'replaceState' : 'pushState']('', document.title, newURL);
}
} else {
if(_historyChanged) {
_windowLoc.replace( newURL );
} else {
_windowLoc.hash = newHash;
}
}
_historyChanged = true;
_hashChangeTimeout = setTimeout(function() {
_hashChangedByScript = false;
}, 60);
};
_registerModule('History', {
publicMethods: {
initHistory: function() {
framework.extend(_options, _historyDefaultOptions, true);
if( !_options.history ) {
return;
}
_windowLoc = window.location;
_urlChangedOnce = false;
_closedFromURL = false;
_historyChanged = false;
_initialHash = _getHash();
_supportsPushState = ('pushState' in history);
if(_initialHash.indexOf('gid=') > -1) {
_initialHash = _initialHash.split('&gid=')[0];
_initialHash = _initialHash.split('?gid=')[0];
}
_listen('afterChange', self.updateURL);
_listen('unbindEvents', function() {
framework.unbind(window, 'hashchange', self.onHashChange);
});
var returnToOriginal = function() {
_hashReseted = true;
if(!_closedFromURL) {
if(_urlChangedOnce) {
history.back();
} else {
if(_initialHash) {
_windowLoc.hash = _initialHash;
} else {
if (_supportsPushState) {
// remove hash from url without refreshing it or scrolling to top
history.pushState('', document.title, _windowLoc.pathname + _windowLoc.search );
} else {
_windowLoc.hash = '';
}
}
}
}
_cleanHistoryTimeouts();
};
_listen('unbindEvents', function() {
if(_closedByScroll) {
// if PhotoSwipe is closed by scroll, we go "back" before the closing animation starts
// this is done to keep the scroll position
returnToOriginal();
}
});
_listen('destroy', function() {
if(!_hashReseted) {
returnToOriginal();
}
});
_listen('firstUpdate', function() {
_currentItemIndex = _parseItemIndexFromURL().pid;
});
var index = _initialHash.indexOf('pid=');
if(index > -1) {
_initialHash = _initialHash.substring(0, index);
if(_initialHash.slice(-1) === '&') {
_initialHash = _initialHash.slice(0, -1);
}
}
setTimeout(function() {
if(_isOpen) { // hasn't destroyed yet
framework.bind(window, 'hashchange', self.onHashChange);
}
}, 40);
},
onHashChange: function() {
if(_getHash() === _initialHash) {
_closedFromURL = true;
self.close();
return;
}
if(!_hashChangedByScript) {
_hashChangedByHistory = true;
self.goTo( _parseItemIndexFromURL().pid );
_hashChangedByHistory = false;
}
},
updateURL: function() {
// Delay the update of URL, to avoid lag during transition,
// and to not to trigger actions like "refresh page sound" or "blinking favicon" to often
_cleanHistoryTimeouts();
if(_hashChangedByHistory) {
return;
}
if(!_historyChanged) {
_updateHash(); // first time
} else {
_historyUpdateTimeout = setTimeout(_updateHash, 800);
}
}
}
});