node-red-nodes/parsers/geohash/70-geohash.js

96 lines
4.1 KiB
JavaScript

module.exports = function(RED) {
"use strict";
var geohash = require('ngeohash');
function GeohashNode(n) {
RED.nodes.createNode(this,n);
var node = this;
var round = function(value, decimals) {
return Number(Math.round(value+'e'+decimals)+'e-'+decimals);
}
this.on("input", function(msg) {
if (msg.hasOwnProperty("location")) {
if (msg.location.hasOwnProperty("geohash")) {
var pos = geohash.decode(msg.location.geohash);
msg.location.lat = round(pos.latitude,5);
msg.location.lon = round(pos.longitude,5);
msg.location.error = { lat:round(pos.error.latitude,5), lon:round(pos.error.longitude,5) };
node.send(msg);
}
else {
var lt = msg.location.lat;
var ln = msg.location.lon;
var le = parseInt(msg.location.precision || 9);
if (le < 1) { le = 1; }
if (le > 9) { le = 9; }
if (lt && ln) {
msg.location.geohash = geohash.encode(lt, ln, le);
node.send(msg);
}
else {
node.warn("lat or lon missing from msg.location");
}
}
}
else if (typeof msg.payload === "string") {
// try to decode it...
var regexp = new RegExp('^[a-z0-9]{1,9}$'); // can only contain a-z or 0-9 and length 1-9
if (regexp.test(msg.payload)) {
var po = geohash.decode(msg.payload);
msg.payload = { lat:round(po.latitude,5), lon:round(po.longitude,5) };
msg.payload.error = { lat:round(po.error.latitude,5), lon:round(po.error.longitude,5) };
node.send(msg);
}
else if (msg.payload.indexOf(",") !== -1) {
// has a comma so assume it's lat,lon(,precision)
var bits = msg.payload.split(",");
if ((bits.length === 2) || (bits.length === 3)) {
var li = 9;
if (bits.length === 3) {
li = parseInt(bits[2]);
if (li < 1) { li = 1; }
if (li > 9) { li = 9; }
}
var la = Number(bits[0]);
if (la < -90) { la = -90; }
if (la > 90) { la = 90; }
var lo = Number(bits[1]);
if (lo < -180) { lo = ((lo-180)%360)+180; }
if (lo > 180) { lo = ((lo+180)%360)-180; }
if (!isNaN(la) && !isNaN(lo)) {
msg.payload = geohash.encode(la, lo, li);
node.send(msg);
}
else {
node.warn("Incorrect string format - should be lat,lon");
}
}
else { node.warn("Unexpected string format - should be lat,lon"); }
}
else { node.warn("Unexpected string format - should either be lat,lon or geohash"); }
}
else if (typeof msg.payload === "object") {
var lat = msg.payload.lat || msg.payload.latitude;
var lon = msg.payload.lon || msg.payload.longitude;
var len = parseInt(msg.payload.precision || 9);
if (len < 1) { len = 1; }
if (len > 9) { len = 9; }
if (lat && lon) {
msg.payload.geohash = geohash.encode(lat, lon, len);
node.send(msg);
}
else {
node.warn("lat or lon missing from msg.payload");
}
}
else {
node.warn("This node only expects strings or objects.");
}
});
}
RED.nodes.registerType("geohash",GeohashNode);
}