restructure: get the tracker to work again

This should hopefully be the final (major) part of the restructuring: a
tracker no longer has to know which trip it is on (and indeed it has no
idea for now), instead the server keeps state about which trips are
currently running and will insert incoming pings in a hopefully
reasonable manner, based on their geoposition & time.

There's lots of associated TODO items here (especially there should be
manual overrides for all this logic in the web ui), but that's work for
a future me.

(incidentally, this also adds support for sending all log messages out
via ntfy-sh)

1 files changed, 137 insertions, 0 deletions

diff --git a/site/tracker.hamlet b/site/tracker.hamlet
new file mode 100644
index 0000000..5877c5d
--- /dev/null
+++ b/site/tracker.hamlet
@@ -0,0 +1,137 @@
+<h1>_{MsgOBU}
+
+<section>
+  <h2>Blub
+  <strong>Token:</strong> <span id="token">
+<section>
+  <h2>Status
+  <p id="status">_{MsgNone}
+  <p id>_{MsgError}: <span id="error">
+<section>
+  <h2>_{MsgLive}
+  <p><strong>Position: </strong><span id="lat"></span>, <span id="long"></span>
+  <p><strong>Accuracy: </strong><span id="acc">
+<section>
+  <h2>_{MsgEstimated}
+  <p><strong>_{MsgDelay}</strong>: <span id="delay">
+  <p><strong>_{MsgSequence}</strong>: <span id="sequence">
+
+
+<script>
+  var token = null;
+
+  let euclid = (a,b) => {
+    let x = a[0]-b[0];
+    let y = a[1]-b[1];
+    return x*x+y*y;
+  }
+
+  let minimalDist = (point, list, proj, norm) => {
+    return list.reduce (
+      (min, x) => {
+        let dist = norm(point, proj(x));
+        return dist < min[0] ? [dist,x] : min
+      },
+      [norm(point, proj(list[0])), list[0]]
+    )[1]
+  }
+
+  let counter = 0;
+  let ws;
+  let id;
+
+  function setStatus(msg) {
+    document.getElementById("status").innerText = msg
+  }
+
+  async function geoError(error) {
+    setStatus("error");
+    alert(`_{MsgPermissionFailed}: \n${error.message}`);
+    console.error(error);
+    main();
+  }
+
+  async function wsError(error) {
+    // alert(`_{MsgWebsocketError}: \n${error.message === undefined ? error.reason : error.message}`);
+    console.log(error);
+    navigator.geolocation.clearWatch(id);
+  }
+
+  async function wsClose(error) {
+    console.log(error);
+    document.getElementById("error").innerText = `websocket closed (reason: ${error.reason}). reconnecting …`;
+    navigator.geolocation.clearWatch(id);
+    setTimeout(openWebsocket, 1000);
+  }
+
+  function wsMsg(msg) {
+    let json = JSON.parse(msg.data);
+    console.log(json);
+    document.getElementById("delay").innerText =
+      `${json.delay}s (${Math.floor(json.delay / 60)}min)`;
+    document.getElementById("sequence").innerText = json.sequence;
+  }
+
+
+  function initGeopos() {
+    document.getElementById("error").innerText = "";
+    id = navigator.geolocation.watchPosition(
+      geoPing,
+      geoError,
+      {enableHighAccuracy: true}
+    );
+  }
+
+
+  function openWebsocket () {
+    ws = new WebSocket((location.protocol == "http:" ? "ws" : "wss") + "://" + location.host + "/api/tracker/ping/ws");
+    ws.onerror = wsError;
+    ws.onclose = wsClose;
+    ws.onmessage = wsMsg;
+    ws.onopen = (event) => {
+      setStatus("connected");
+    };
+  }
+
+  async function geoPing(geoloc) {
+    console.log("got position update " + counter);
+    document.getElementById("lat").innerText = geoloc.coords.latitude;
+    document.getElementById("long").innerText = geoloc.coords.longitude;
+    document.getElementById("acc").innerText = geoloc.coords.accuracy;
+
+    if (ws !== undefined && ws.readyState == 1) {
+        ws.send(JSON.stringify({
+            token: token,
+            geopos: [ geoloc.coords.latitude, geoloc.coords.longitude ],
+            timestamp: (new Date()).toISOString()
+        }));
+        counter += 1;
+        setStatus(`sent ${counter} pings`);
+    } else {
+        setStatus(`websocket readystate ${ws.readyState}`);
+    }
+  }
+
+
+  async function main() {
+    initGeopos();
+
+    token = await (await fetch("/api/tracker/register/", {
+      method: "POST",
+      body: JSON.stringify({agent: "tracktrain-website"}),
+      headers: {"Content-Type": "application/json"}
+    })).json();
+
+    if (token.error) {
+      alert("could not obtain token: \n" + token.msg);
+      setStatus("_{MsgTokenFailed}");
+    } else {
+      console.log("got token");
+
+      document.getElementById("token").innerText = token;
+
+      openWebsocket();
+    }
+  }
+
+  main()