[gnome-maps/wip/mlundblad/transit-routing: 1/2] WIP: Add module to query an OpenTripPlanner instance

[Marcus Lundblad <mlundblad src gnome org>]

commit 54b28d9d669fd028f45fbe5b53d0365e1d982e47
Author: Marcus Lundblad <ml update uu se>
Date:   Mon Feb 15 23:18:14 2016 +0100

    WIP: Add module to query an OpenTripPlanner instance

 src/openTripPlanner.js               |  156 ++++++++++++++++++++++++++++++++++
 src/org.gnome.Maps.src.gresource.xml |    1 +
 2 files changed, 157 insertions(+), 0 deletions(-)
---
diff --git a/src/openTripPlanner.js b/src/openTripPlanner.js
new file mode 100644
index 0000000..9f10196
--- /dev/null
+++ b/src/openTripPlanner.js
@@ -0,0 +1,156 @@
+/* -*- Mode: JS2; indent-tabs-mode: nil; js2-basic-offset: 4 -*- */
+/* vim: set et ts=4 sw=4: */
+/*
+ * Copyright (c) 2016 Marcus Lundblad
+ *
+ * GNOME Maps is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * GNOME Maps is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with GNOME Maps; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Author: Marcus Lundblad <ml update uu se>
+ */
+
+const Lang = imports.lang;
+
+const Soup = imports.gi.Soup;
+
+const Application = imports.application;
+const RouteQuery = imports.routeQuery;
+const Utils = imports.utils;
+
+/* base URL used for testing against a local OTP instance for now */
+const _BASE_URL = 'http://localhost:8080/otp';
+
+/* timeout after which the routers data is considered stale and we will force
+   a reload (24 hours) */
+const _ROUTERS_TIMEOUT = 24 * 60 * 60;
+
+const OpenTripPlanner = new Lang.Class({
+    Name: 'OpenTripPlanner',
+
+    _init: function() {
+        this._session = new Soup.Session();
+        /* initially set routers as updated far back in the past to force
+           a download when first request */
+        this._routersUpdatedTimestamp = 0;
+        this._query = Application.routeQuery;
+    },
+
+    connect: function() {
+        this._signalHandler = this._query.connect('notify::points', (function() {
+            if (this._query.isValid())
+                this.fetchRoute(this._query.filledPoints);
+        }).bind(this));
+    },
+
+    disconnect: function() {
+        if (this._signalHandler !== 0) {
+            this._query.disconnect(this._signalHandler);
+            this._signalHandler = 0;
+        }
+    },
+
+    _fetchRouters: function(callback) {
+        let currentTime = (new Date()).getTime();
+
+        if (currentTime - this._routersUpdatedTimestamp < _ROUTERS_TIMEOUT) {
+            callback(true);
+        } else {
+            let uri = new Soup.URI(_BASE_URL + '/routers');
+            let request = new Soup.Message({ method: 'GET', uri: uri });
+
+            request.request_headers.append('Accept', 'application/json');
+            this._session.queue_message(request, (function(obj, message) {
+                if (message.status_code !== Soup.Status.OK) {
+                    callback(false);
+                    return;
+                }
+
+                Utils.debug('routers: ' + message.response_body.data);
+                try {
+                    this._routers = JSON.parse(message.response_body.data);
+                    this._routersUpdatedTimestamp = (new Date()).getTime();
+                    callback(true);
+                } catch (e) {
+                    Utils.debug('Failed to parse router information');
+                    callback(false);
+                }
+            }).bind(this));
+        }
+    },
+
+    _getRoutersForPlace: function(place) {
+        let routers = [];
+
+        Utils.debug('_getRotersForPlace');
+        Utils.debug('place coords: ' + place.location.latitude + ', ' + place.location.longitude);
+
+        this._routers.routerInfo.forEach((function(routerInfo) {
+            Utils.debug('checking router: ' + routerInfo.routerId);
+
+            /* TODO: only check bounding rectangle for now
+               should we try to do a finer-grained check using the bounding
+               polygon (if OTP gives one for the routers).
+               And should we add some margins to allow routing from just outside
+               a network (walking distance)? */
+            if (place.location.latitude >= routerInfo.lowerLeftLatitude &&
+                place.location.latitude <= routerInfo.upperRightLatitude &&
+                place.location.longitude >= routerInfo.lowerLeftLongitude &&
+                place.location.longitude <= routerInfo.upperRightLongitude)
+                routers.push(routerInfo.routerId);
+        }));
+
+        return routers;
+    },
+
+    /* Note: this is theoretically slow (O(n*m)), but we will have filtered
+       possible routers for the starting and ending query point, so they should
+       be short (in many cases just one element) */
+    _routerIntersection: function(routers1, routers2) {
+        return routers1.filter(function(n) {
+            return routers2.indexOf(n) != -1;
+        });
+    },
+
+    fetchRoute: function(points) {
+        this._fetchRouters((function(success) {
+            if (success) {
+                let routers = this._getRoutersForPoints(points);
+
+                if (routers.length > 0) {
+
+                } else {
+                    Application.notificationManager.showMessage(_("No route found"));
+                }
+            } else {
+                Application.notificationManager.showMessage(_("Route request failed."));
+            }
+        }).bind(this));
+    },
+
+    _getRoutersForPoints: function(points) {
+        Utils.debug('sucessfully fetched routers list, points.length ' + points.length);
+        let startRouters = this._getRoutersForPlace(points[0].place);
+        let endRouters =
+            this._getRoutersForPlace(points[points.length - 1].place);
+
+        Utils.debug('routers at start point: ' + startRouters);
+        Utils.debug('routers at end point: ' + endRouters);
+        let intersectingRouters =
+            this._routerIntersection(startRouters, endRouters);
+
+        Utils.debug('intersecting routers: ' + intersectingRouters);
+
+        return intersectingRouters;
+    }
+})
diff --git a/src/org.gnome.Maps.src.gresource.xml b/src/org.gnome.Maps.src.gresource.xml
index ecd8ef4..6dc4570 100644
--- a/src/org.gnome.Maps.src.gresource.xml
+++ b/src/org.gnome.Maps.src.gresource.xml
@@ -34,6 +34,7 @@
     <file>mapView.js</file>
     <file>mapWalker.js</file>
     <file>notification.js</file>
+    <file>openTripPlanner.js</file>
     <file>notificationManager.js</file>
     <file>osmAccountDialog.js</file>
     <file>osmConnection.js</file>