[gnome-maps/wip/mlundblad/transit-plugin-gtfs-local: 14/14] WIP: Add transit plugin doing local routing on dowloaded GTFS

[Marcus Lundblad <mlundblad src gnome org>]

commit a491bd1b36c15ab4f3a81294f4c650aa4147a3e9
Author: Marcus Lundblad <ml update uu se>
Date:   Wed Feb 19 23:10:55 2020 +0100

    WIP: Add transit plugin doing local routing on dowloaded GTFS

 po/POTFILES.in                       |   1 +
 src/org.gnome.Maps.src.gresource.xml |   1 +
 src/transitplugins/gtfs.js           | 158 +++++++++++++++++++++++++++++++++++
 3 files changed, 160 insertions(+)
---
diff --git a/po/POTFILES.in b/po/POTFILES.in
index 676a7a6f..6dfac517 100644
--- a/po/POTFILES.in
+++ b/po/POTFILES.in
@@ -62,4 +62,5 @@ src/translations.js
 src/userLocationBubble.js
 src/utils.js
 src/transitplugins/goMetro.js
+src/transitplugins/gtfs.js
 src/transitplugins/openTripPlanner.js
diff --git a/src/org.gnome.Maps.src.gresource.xml b/src/org.gnome.Maps.src.gresource.xml
index ab2e12f0..6c87c7d0 100644
--- a/src/org.gnome.Maps.src.gresource.xml
+++ b/src/org.gnome.Maps.src.gresource.xml
@@ -115,6 +115,7 @@
     <file alias="geojsonvt/transform.js">transform.js</file>
     <file alias="geojsonvt/wrap.js">wrap.js</file>
     <file>transitplugins/goMetro.js</file>
+    <file>transitplugins/gtfs.js</file>
     <file>transitplugins/opendataCH.js</file>
     <file>transitplugins/openTripPlanner.js</file>
     <file>transitplugins/resrobot.js</file>
diff --git a/src/transitplugins/gtfs.js b/src/transitplugins/gtfs.js
new file mode 100644
index 00000000..df662a80
--- /dev/null
+++ b/src/transitplugins/gtfs.js
@@ -0,0 +1,158 @@
+/* -*- Mode: JS2; indent-tabs-mode: nil; js2-basic-offset: 4 -*- */
+/* vim: set et ts=4 sw=4: */
+/*
+ * Copyright (c) 2020 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, see <http://www.gnu.org/licenses/>.
+ *
+ * Author: Marcus Lundblad <ml update uu se>
+ */
+
+const _ = imports.gettext.gettext;
+
+const Maps = imports.gi.GnomeMaps;
+
+const Application = imports.application;
+const GraphHopperTransit = imports.graphHopperTransit;
+const HVT = imports.hvt;
+const TransitPlan = imports.transitPlan;
+const Utils = imports.utils;
+
+const NUM_CONSIDERED_STOPS = 10;
+
+var GTFS = class GTFS {
+    constructor(params) {
+        // TODO: for now just read files from an unzipped GTFS file at path…
+        this._gtfs = Maps.GTFS.new(params.name);
+        this._query = Application.routeQuery;
+        this._plan = Application.routingDelegator.transitRouter.plan;
+        Utils.debug('end constructor');
+    }
+
+    fetchFirstResults() {
+        let filledPoints = this._query.filledPoints;
+        let startLat = filledPoints[0].place.location.latitude;
+        let startLon = filledPoints[0].place.location.longitude;
+        let endLat = filledPoints.last().place.location.latitude;
+        let endLon = filledPoints.last().place.location.longitude;
+
+        this._plan.progress(_("Creating database…"));
+        this._gtfs.parse((success, error) => {
+            this._plan.progress(null);
+            if (success) {
+                let types = this._getRouteTypesFromQuery();
+                Utils.debug('parse done');
+                let startStops =
+                    types ?
+                    this._gtfs.get_nearby_stops_with_route_types(startLat,
+                                                                 startLon,
+                                                                 2000, types) :
+                            this._gtfs.get_nearby_stops(startLat, startLon, 2000);
+                Utils.debug('got nearby start');
+                let endStops =
+                    types ?
+                    this._gtfs.get_nearby_stops_with_route_types(endLat, endLon,
+                                                                 2000, types) :
+                    this._gtfs.get_nearby_stops(endLat, endLon, 2000);
+                Utils.debug('got nearny end');
+
+                this._refineStops(startStops, true, (result) => {
+                    result.forEach((stop) => {
+                        Utils.debug('stop: ' + stop.name + ", walking: " +
+                                    stop.walkRoute.distance);
+                    });
+                });
+            } else {
+                this._plan.requestFailed();
+            }
+        });
+    }
+
+    fetchMoreResults() {
+
+    }
+
+    _getRouteTypesFromQuery() {
+        if (this._query.transitOptions.showAllTransitTypes) {
+            return null;
+        } else {
+            let types = [];
+
+            this._query.transitOptions.transitTypes.forEach(type => {
+                switch (type) {
+                    case TransitPlan.RouteType.BUS:
+                        types.push(TransitPlan.RouteType.BUS);
+                        types.push(TransitPlan.RouteType.TROLLEYBUS);
+                        types.push(HVT.COACH_SERVICE);
+                        types.push(HVT.BUS_SERVICE);
+                        types.push(HVT.TROLLEYBUS_SERVICE);
+                        types.push(HVT.TAXI_SERVICE);
+                        break;
+                    case TransitPlan.RouteType.TRAM:
+                        types.push(TransitPlan.RouteType.TRAM);
+                        types.push(HVT.TRAM_SERVICE);
+                        break;
+                    case TransitPlan.RouteType.SUBWAY:
+                        types.push(TransitPlan.RouteType.SUBWAY);
+                        types.push(HVT.URBAN_RAILWAY_SERVICE);
+                        types.push(HVT.SUBURBAN_RAILWAY_SERVICE);
+                        types.push(HVT.METRO_SERVICE);
+                        break;
+                    case TransitPlan.RouteType.TRAIN:
+                        types.push(TransitPlan.RouteType.TRAIN);
+                        types.push(HVT.RAILWAY_SERVICE);
+                        break;
+                    case TransitPlan.RouteType.FERRY:
+                        types.push(TransitPlan.RouteType.FERRY);
+                        types.push(HVT.WATER_TRANSPORT_SERVICE);
+                        break;
+                    case HVT.AIR_SERVICE:
+                        types.push(HVT.AIR_SERVICE);
+                        break;
+                }
+            });
+
+            return types;
+        }
+
+    }
+
+    _refineStops(stops, isStart, callback) {
+        this._refineStopsRecursive(stops, [], 0, isStart, callback);
+    }
+
+    _refineStopsRecursive(stops, result, index, isStart, callback) {
+        if (index >= stops.length || index == NUM_CONSIDERED_STOPS) {
+            callback(result);
+        } else {
+            let filledPoints = this._query.filledPoints;
+            let stop = stops[index];
+            let startPoint =
+                isStart ?
+                filledPoints[0] :
+                GraphHopperTransit.createQueryPointForCoord([stop.lat, stop.lon]);
+            let endPoint =
+                isStart ?
+                GraphHopperTransit.createQueryPointForCoord([stop.lat, stop.lon]) :
+                filledPoints.last();
+
+            GraphHopperTransit.fetchWalkingRoute([startPoint, endPoint],
+                                                 (route) => {
+                stop.walkRoute = route;
+                result.push(stop);
+                this._refineStopsRecursive(stops, result, index + 1, isStart, callback);
+            });
+        }
+    }
+}