Initial weather support

src/pkjs/weather.js

@@ -0,0 +1,42 @@
+var xhrRequest = function (url, type, callback) {
+    var xhr = new XMLHttpRequest();
+    xhr.onload = function () {
+        callback(this.responseText);
+    };
+    xhr.open(type, url);
+    xhr.send();
+};
+
+function locationSuccess(pos) {
+    var url = 'https://api.open-meteo.com/v1/forecast?' +
+        'latitude=' + pos.coords.latitude +
+        '&longitude=' + pos.coords.longitude +
+        '&current=temperature_2m';
+
+    xhrRequest(url, 'GET',
+        function (responseText) {
+            var json = JSON.parse(responseText);
+
+            // clamp into a range of 80 (technically 81)C (-32,48), -32C=-25.6F, 48C=118.4F
+            var temperature = Math.min(Math.max(json.current.temperature_2m, -32), 48);
+            // set set range minimum to 0 (add 32) and convert to bars (0-20)
+            temperature = Math.round((temperature + 32) / 4);
+
+            Pebble.sendAppMessage({ PKJS_TEMP_BAR_COUNT: temperature });
+        }
+    );
+}
+
+function getWeather() {
+    navigator.geolocation.getCurrentPosition(
+        locationSuccess,
+        null,
+        { timeout: 15000, maximumAge: 60000 }
+    );
+}
+
+Pebble.addEventListener("appmessage", function (dict) {
+    if (dict.payload["PKJS_TEMP_BAR_COUNT"]) {
+        getWeather();
+    }
+});