'use strict';
/*global require*/
var CesiumEvent = require('terriajs-cesium/Source/Core/Event');
var defaultValue = require('terriajs-cesium/Source/Core/defaultValue');
var defined = require('terriajs-cesium/Source/Core/defined');
var defineProperties = require('terriajs-cesium/Source/Core/defineProperties');
var DeveloperError = require('terriajs-cesium/Source/Core/DeveloperError');
var EventHelper = require('terriajs-cesium/Source/Core/EventHelper');
var knockout = require('terriajs-cesium/Source/ThirdParty/knockout');
var raiseErrorToUser = require('./raiseErrorToUser');
/**
* The model for the "Now Viewing" pane.
*/
var NowViewing = function(terria) {
this._terria = terria;
this._eventSubscriptions = new EventHelper();
/**
* Gets the list of items that we are "now viewing". It is recommended that you use
* the methods on this instance instead of manipulating the list of items directly.
* This property is observable.
* @type {CatalogItem[]}
*/
this.items = [];
knockout.track(this, ['items']);
this.showNowViewingRequested = new CesiumEvent();
this._eventSubscriptions.add( this.terria.beforeViewerChanged, function() {
beforeViewerChanged(this);
}, this);
this._eventSubscriptions.add( this.terria.afterViewerChanged, function() {
afterViewerChanged(this);
}, this);
};
defineProperties(NowViewing.prototype, {
/**
* Gets the Terria instance.
* @memberOf NowViewing.prototype
* @type {Terria}
*/
terria : {
get : function() {
return this._terria;
}
},
/**
* Gets a value indicating whether the "Now Viewing" pane has one or more items.
* @memberOf NowViewing.prototype
* @type {Boolean}
*/
hasItems : {
get : function() {
return this.items.length > 0;
}
},
/**
* Gets a value indicating whether the "Now Viewing" pane has at list own data
* source that is currently shown.
* @memberOf NowViewing.prototype
* @type {Boolean}
*/
hasShownItems : {
get : function() {
for (var i = 0; i < this.items.length; ++i) {
if (this.items[i].isShown) {
return true;
}
}
return false;
}
},
hasChildren : {
get : function() {
return this.items.length > 0;
}
},
});
/**
* Destroys this instance, including unsubscribing it from any events.
*/
NowViewing.prototype.destroy = function() {
this._eventSubscriptions.removeAll();
};
/**
* Adds an item to the "Now Viewing" pane.
*
* @param {CatalogMember} item The item to add.
*/
NowViewing.prototype.add = function(item, index) {
index = defaultValue(index, 0);
// Keep reorderable data sources (e.g.: imagery layers) below non-orderable ones (e.g.: GeoJSON).
if (item.supportsReordering) {
while (index < this.items.length && !this.items[index].supportsReordering) {
++index;
}
} else {
while (index > 0 && this.items.length > 0 && this.items[index - 1].supportsReordering) {
--index;
}
}
if (!item.keepOnTop) {
while (index < this.items.length && this.items[index].keepOnTop && this.items[index].supportsReordering === item.supportsReordering) {
++index;
}
} else {
while (index > 0 && this.items.length > 0 && this.items[index - 1].keepOnTop && this.items[index - 1] === item.supportsReordering) {
--index;
}
}
this.items.splice(index, 0, item);
};
/**
* Removes an item from the "Now Viewing" pane and from the map.
*
* @param {CatalogMember} item The item to remove.
*/
NowViewing.prototype.remove = function(item) {
item.isEnabled = false;
this.items.remove(item);
};
/**
* Removes all data sources from the "Now Viewing" pane and from the map.
*/
NowViewing.prototype.removeAll = function() {
// Work backwards through the list of items because setting isEnabled=false
// will usually remove the item from the list.
for (var i = this.items.length - 1; i >= 0; --i) {
this.items[i].isEnabled = false;
}
this.items.removeAll();
};
/**
* Raises an item, making it displayed on top of the item that is currently above it. If it
* is nonsensical to move this item up (e.g. it is already at the top), this method does nothing.
*
* @param {CatalogMember} item The item to raise.
* @param {Number} [index] The index of the item of the list, if it is already known.
*/
NowViewing.prototype.raise = function(item, index) {
if (defined(index)) {
if (this.items[index] !== item) {
throw new DeveloperError('The provided index is not correct.');
}
} else {
index = this.items.indexOf(item);
if (index < 0) {
return;
}
}
if (index === 0) {
return;
}
// Don't allow reorderable data sources to move above non-reorderable ones.
if (item.supportsReordering && !this.items[index - 1].supportsReordering) {
return;
}
var terria = this.terria;
terria.currentViewer.raise(index);
this.items.splice(index, 1);
this.items.splice(index - 1, 0, item);
terria.currentViewer.updateLayerOrderAfterReorder();
terria.currentViewer.notifyRepaintRequired();
};
/**
* Lowers an item, making it displayed below the item that is currently below it. If it
* is nonsensical to move this item down (e.g. it is already at the bottom), this method does nothing.
*
* @param {CatalogMember} item The item to lower.
* @param {Number} [index] The index of the item of the list, if it is already known.
*/
NowViewing.prototype.lower = function(item, index) {
if (defined(index)) {
if (this.items[index] !== item) {
throw new DeveloperError('The provided index is not correct.');
}
} else {
index = this.items.indexOf(item);
if (index < 0) {
return;
}
}
if (index === this.items.length - 1) {
return;
}
var itemBelow = this.items[index + 1];
// Don't allow non-reorderable data sources to move below reorderable ones.
if (!item.supportsReordering && itemBelow.supportsReordering) {
return;
}
var terria = this.terria;
terria.currentViewer.lower(index);
this.items.splice(index, 1);
this.items.splice(index + 1, 0, item);
terria.currentViewer.updateLayerOrderAfterReorder();
terria.currentViewer.notifyRepaintRequired();
};
/**
* Toggles the {@link NowViewing#isOpen} flag. If it's open, it is closed. If it's closed, it is opened.
*/
NowViewing.prototype.toggleOpen = function() {
this.isOpen = !this.isOpen;
};
/**
* Records the the index of each data source in the Now Viewing list in a {@link CatalogItem#nowViewingIndex} property
* on the data source. This is used to save the state of the Now Viewing list and is not intended for general
* use.
* @private
*/
NowViewing.prototype.recordNowViewingIndices = function() {
for (var i = 0; i < this.items.length; ++i) {
this.items[i].nowViewingIndex = i;
}
};
/**
* Sorts the data sources in the Now Viewing list by their {@link CatalogItem#nowViewingIndex} properties. This is used
* to restore the state of the Now Viewing list and is not intended for general use.
* @private
*/
NowViewing.prototype.sortByNowViewingIndices = function() {
var sortedItems = this.items.slice();
sortedItems.sort(function(a, b) {
return a.nowViewingIndex - b.nowViewingIndex;
});
for (var i = 0; i < sortedItems.length; ++i) {
var item = sortedItems[i];
var existingIndex = this.items.indexOf(item);
var lastIndex;
// Check if raise didn't succeed (ie. item's index didn't change), and quit the loop if so.
while (existingIndex > i && existingIndex !== lastIndex) {
lastIndex = existingIndex;
this.raise(item, lastIndex);
existingIndex = this.items.indexOf(item);
}
}
if (defined( this.terria.currentViewer)) {
this.terria.currentViewer.notifyRepaintRequired();
}
};
function beforeViewerChanged(nowViewing) {
// Hide and disable all data sources, without actually changing
// their isEnabled and isShown flags.
var dataSources = nowViewing.items;
for (var i = 0; i < dataSources.length; ++i) {
var dataSource = dataSources[i];
if (defined(dataSource._loadForEnablePromise)) {
continue;
}
if (dataSource.isShown) {
dataSource._hide();
}
if (dataSource.isEnabled) {
dataSource._disable();
}
}
}
function afterViewerChanged(nowViewing) {
// Re-enable and re-show all data sources that were previously enabled or shown.
// Work from the bottom data source up so that the correct order is created.
var dataSources = nowViewing.items;
for (var i = dataSources.length - 1; i >= 0; --i) {
var dataSource = dataSources[i];
if (defined(dataSource._loadForEnablePromise)) {
continue;
}
if (dataSource.isEnabled) {
try {
dataSource._enable();
} catch(e) {
raiseErrorToUser(nowViewing.terria, e);
}
//Re-enable attribution
nowViewing.terria.currentViewer.addAttribution(dataSource.attribution);
}
if (dataSource.isShown) {
try {
dataSource._show();
} catch(e) {
raiseErrorToUser(nowViewing.terria, e);
}
}
}
}
module.exports = NowViewing;