Fixe #472: Add !units parser for feet, inches, m, cm

Parsers/Convert length units.js

@@ -0,0 +1,78 @@
+/*
+activation_example:!units 10 ft to m
+regex:!units\b
+flags:gmi
+order:200
+stop_processing:false
+*/
+
+var USAGE = 'Usage: `!units 10 ft to m`. Supports mm, cm, m, km, in, ft, yd, mi.';
+var input = current.text.replace(/!units\b/gmi, '').trim();
+
+if (input == '') {
+    new x_snc_slackerbot.Slacker().send_chat(current, USAGE, true);
+} else {
+    var match = input.match(/^(-?\d+\.?\d*)\s*([a-z]+)\s+to\s+([a-z]+)$/i);
+    if (!match) {
+        new x_snc_slackerbot.Slacker().send_chat(current, USAGE, true);
+    } else {
+        var amount = parseFloat(match[1]);
+        var fromUnit = match[2].toLowerCase();
+        var toUnit = match[3].toLowerCase();
+        var fromMeters = unitToMeters(fromUnit);
+        var toMeters = unitToMeters(toUnit);
+
+        if (isNaN(amount) || fromMeters === null || toMeters === null) {
+            new x_snc_slackerbot.Slacker().send_chat(current, ':exclamation: Unknown unit. ' + USAGE, true);
+        } else {
+            var converted = amount * (fromMeters / toMeters);
+            new x_snc_slackerbot.Slacker().send_chat(current, amount + ' ' + fromUnit + ' is ' + formatNumber(converted) + ' ' + toUnit + '.', false);
+        }
+    }
+}
+
+function unitToMeters(unit) {
+    var units = {
+        mm: 0.001,
+        millimeter: 0.001,
+        millimeters: 0.001,
+        millimetre: 0.001,
+        millimetres: 0.001,
+        cm: 0.01,
+        centimeter: 0.01,
+        centimeters: 0.01,
+        centimetre: 0.01,
+        centimetres: 0.01,
+        m: 1,
+        meter: 1,
+        meters: 1,
+        metre: 1,
+        metres: 1,
+        km: 1000,
+        kilometer: 1000,
+        kilometers: 1000,
+        kilometre: 1000,
+        kilometres: 1000,
+        in: 0.0254,
+        inch: 0.0254,
+        inches: 0.0254,
+        ft: 0.3048,
+        foot: 0.3048,
+        feet: 0.3048,
+        yd: 0.9144,
+        yard: 0.9144,
+        yards: 0.9144,
+        mi: 1609.344,
+        mile: 1609.344,
+        miles: 1609.344
+    };
+
+    if (units.hasOwnProperty(unit)) {
+        return units[unit];
+    }
+    return null;
+}
+
+function formatNumber(num) {
+    return String(Number(num.toFixed(4)));
+}