info: added map credits

lib/widgets/fullscreen/info/maps/leaflet_map.dart

@@ -4,8 +4,10 @@ import 'package:aves/widgets/common/icons.dart';
 import 'package:aves/widgets/fullscreen/info/maps/scale_layer.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
+import 'package:flutter_markdown/flutter_markdown.dart';
 import 'package:latlong/latlong.dart';
 import 'package:tuple/tuple.dart';
+import 'package:url_launcher/url_launcher.dart';
 
 import '../location_section.dart';
 
@@ -45,7 +47,10 @@ class EntryLeafletMapState extends State<EntryLeafletMap> with AutomaticKeepAliv
   Widget build(BuildContext context) {
     super.build(context);
     final accentColor = Theme.of(context).accentColor;
-    return Row(
+    return Column(
+      crossAxisAlignment: CrossAxisAlignment.start,
+      children: [
+        Row(
           children: [
             Expanded(
               child: GestureDetector(
@@ -119,6 +124,9 @@ class EntryLeafletMapState extends State<EntryLeafletMap> with AutomaticKeepAliv
               ]),
             )
           ],
+        ),
+        _buildAttribution(),
+      ],
     );
   }
 
@@ -135,6 +143,39 @@ class EntryLeafletMapState extends State<EntryLeafletMap> with AutomaticKeepAliv
     }
   }
 
+  Widget _buildAttribution() {
+    final attribution = _getAttributionMarkdown();
+    return attribution != null
+        ? Markdown(
+            data: attribution,
+            selectable: true,
+            styleSheet: MarkdownStyleSheet(
+              a: TextStyle(color: Theme.of(context).accentColor),
+              p: TextStyle(fontSize: 13, fontFamily: 'Concourse'),
+            ),
+            onTapLink: (url) async {
+              if (await canLaunch(url)) {
+                await launch(url);
+              }
+            },
+            padding: EdgeInsets.symmetric(vertical: 4, horizontal: 8),
+            shrinkWrap: true,
+          )
+        : SizedBox.shrink();
+  }
+
+  String _getAttributionMarkdown() {
+    switch (widget.style) {
+      case EntryMapStyle.osmHot:
+        return '© [OpenStreetMap](https://www.openstreetmap.org/copyright) contributors, Tiles style by [Humanitarian OpenStreetMap Team](https://www.hotosm.org/) hosted by [OpenStreetMap France](https://openstreetmap.fr/)';
+      case EntryMapStyle.stamenToner:
+      case EntryMapStyle.stamenWatercolor:
+        return 'Map tiles by [Stamen Design](http://stamen.com), [CC BY 3.0](http://creativecommons.org/licenses/by/3.0) — Map data © [OpenStreetMap](https://www.openstreetmap.org/copyright) contributors';
+      default:
+        return null;
+    }
+  }
+
   void _zoomBy(double amount) {
     final endZoom = (settings.infoMapZoom + amount).clamp(1.0, 16.0);
     settings.infoMapZoom = endZoom;
@@ -162,7 +203,6 @@ class OSMHotLayer extends StatelessWidget {
   Widget build(BuildContext context) {
     return TileLayerWidget(
       options: TileLayerOptions(
-        // attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors, Tiles style by <a href="https://www.hotosm.org/" target="_blank">Humanitarian OpenStreetMap Team</a> hosted by <a href="https://openstreetmap.fr/" target="_blank">OpenStreetMap France</a>'
         urlTemplate: 'https://{s}.tile.openstreetmap.fr/hot/{z}/{x}/{y}.png',
         subdomains: ['a', 'b', 'c'],
         retinaMode: MediaQuery.of(context).devicePixelRatio > 1,
@@ -176,7 +216,6 @@ class StamenTonerLayer extends StatelessWidget {
   Widget build(BuildContext context) {
     return TileLayerWidget(
       options: TileLayerOptions(
-        // attribution: 'Map tiles by <a href="http://stamen.com">Stamen Design</a>, <a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a> &mdash; Map data &copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
         urlTemplate: 'https://stamen-tiles-{s}.a.ssl.fastly.net/toner-lite/{z}/{x}/{y}{r}.png',
         subdomains: ['a', 'b', 'c', 'd'],
         retinaMode: MediaQuery.of(context).devicePixelRatio > 1,
@@ -190,7 +229,6 @@ class StamenWatercolorLayer extends StatelessWidget {
   Widget build(BuildContext context) {
     return TileLayerWidget(
       options: TileLayerOptions(
-        // attribution: 'Map tiles by <a href="http://stamen.com">Stamen Design</a>, <a href="http://creativecommons.org/licenses/by/3.0">CC BY 3.0</a> &mdash; Map data &copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors',
         urlTemplate: 'https://stamen-tiles-{s}.a.ssl.fastly.net/watercolor/{z}/{x}/{y}.jpg',
         subdomains: ['a', 'b', 'c', 'd'],
         retinaMode: MediaQuery.of(context).devicePixelRatio > 1,