First commit

There was history before but now there is no more.

util.js

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: Unlicense
+
+// If text contains key, make it stand out; otherwise, append [key] to text.
+function addShortcut(text, key) {
+    if (!key)
+        return text
+    else if (text.indexOf(key) < 0)
+        return `${text} [<b>${key}</b>]`
+    else
+        return text.replace(new RegExp('\(' + key + '\)'), '<b>$1</b>')
+}
+
+// Set alpha value for color.
+function alphize(color, alpha) {
+    return Qt.hsla(color.hslHue, color.hslSaturation, color.hslLightness, alpha)
+}
+
+// Return the last event in list with property not greater than value.
+function find(list, property, value) {
+    var low = 0
+    var high = list.count - 1
+    while (low <= high) {
+        var mid = Math.floor((low + high) / 2)
+        if (list.get(mid)[property] <= value)
+            low = mid + 1
+        else
+            high = mid - 1
+    }
+    return low
+}