From 1a2777417734528ad279d2a22a4929a025f95b11 Mon Sep 17 00:00:00 2001
From: James Graham <j.graham@software.ac.uk>
Date: Wed, 16 Dec 2020 12:09:10 +0000
Subject: [PATCH] feat: add location search to picker

Requires API key with Google Places API access
Currently untested
---
 people/static/js/location_picker.js        | 62 ++++++++++++++++++++--
 people/templates/people/person/update.html |  5 +-
 2 files changed, 61 insertions(+), 6 deletions(-)

diff --git a/people/static/js/location_picker.js b/people/static/js/location_picker.js
index 0488204..8b9ffa2 100644
--- a/people/static/js/location_picker.js
+++ b/people/static/js/location_picker.js
@@ -12,6 +12,10 @@ const marker_edge_width = 1.0;
 
 let marker = null;
 
+/**
+ * Position a map marker at the clicked location and update lat/long form fields.
+ * @param {Event} event - Click event from a Google Map.
+ */
 function selectLocation(event) {
     if (marker === null) {
         // Generate a new marker
@@ -34,16 +38,66 @@ function selectLocation(event) {
     }
 
     const pos = marker.getPosition();
-    console.log(pos.lat(), pos.lng());
     document.getElementById('id_latitude').value = pos.lat();
     document.getElementById('id_longitude').value = pos.lng();
 }
 
-// The function called when Google Maps starts up
+/**
+ * Initialise Google Maps element after library is loaded.
+ */
 function initMap() {
-    const centre_latlng = new google.maps.LatLng(settings.centre_lat, settings.centre_lng);
+    const centre_latlng = new google.maps.LatLng(settings.centre_lat | 0, settings.centre_lng | 0);
     const map = new google.maps.Map(
         document.getElementById('map'), { zoom: settings.zoom, center: centre_latlng });
 
-    google.maps.event.addListener(map, 'click', selectLocation)
+    const search_input = document.getElementById('location-search')
+    const search_box = new google.maps.places.SearchBox(search_input)
+    map.controls[google.maps.ControlPosition.TOP_LEFT].push(search_input)
+
+    map.addListener('bounds_changed', () => {
+        search_box.setBounds(map.getBounds())
+    })
+
+    let markers = []
+
+    search_box.addListener('places_changed', () => {
+        const places = search_box.getPlaces()
+
+        if (places.length === 0) return
+
+        for (const marker of markers) marker.setMap(null)
+        markers = []
+
+        const bounds = new google.maps.LatLngBounds()
+        for (const place of places) {
+            if (!place.geometry) {
+                console.error('Place contains no geometry')
+                continue
+            }
+
+            const icon = {
+                size: new google.maps.Size(71, 71),
+                origin: new google.maps.Point(0, 0),
+                anchor: new google.maps.Point(17, 34),
+                scaledSize: new google.maps.Size(25, 25),
+            }
+
+            markers.push(
+                new google.maps.Marker({
+                    map, icon, title: place.name, position: place.geometry.location
+                })
+            )
+
+            if (place.geometry.viewport) {
+                bounds.union(place.geometry.viewport)
+            } else {
+                bounds.extend(place.geometry.location)
+            }
+
+        }
+
+        map.fitBounds(bounds)
+    })
+
+    map.addListener('click', selectLocation)
 }
diff --git a/people/templates/people/person/update.html b/people/templates/people/person/update.html
index 6bc0e5e..2e22b07 100644
--- a/people/templates/people/person/update.html
+++ b/people/templates/people/person/update.html
@@ -12,7 +12,7 @@
         ]
 
         const settings = {
-            zoom: 8,
+            zoom: 2,
             centre_lat: '{{ answer_set.latitude }}',
             centre_lng: '{{ answer_set.longitude }}',
         }
@@ -20,7 +20,7 @@
 
     <script src="{% static 'js/location_picker.js' %}"></script>
 
-    <script async defer src="https://maps.googleapis.com/maps/api/js?key={{ settings.GOOGLE_MAPS_API_KEY }}&callback=initMap"
+    <script async defer src="https://maps.googleapis.com/maps/api/js?key={{ settings.GOOGLE_MAPS_API_KEY }}&callback=initMap&libraries=places"
                         type="text/javascript"></script>
 {% endblock %}
 
@@ -58,6 +58,7 @@
 
     <hr>
 
+    <input id="location-search" class="controls" type="text" placeholder="Location Search"/>
     <div id="map" style="height: 800px; width: 100%"></div>
 
     <hr>