Initial project upload

frontend/node_modules/spacetime/src/timezone/parseOffset.js

@@ -0,0 +1,40 @@
+const isOffset = /(-?[0-9]+)h(rs)?/i
+const isNumber = /(-?[0-9]+)/
+const utcOffset = /utc([\-+]?[0-9]+)/i
+const gmtOffset = /gmt([\-+]?[0-9]+)/i
+
+const toIana = function (num) {
+  num = Number(num)
+  if (num >= -13 && num <= 13) {
+    num = num * -1 //it's opposite!
+    num = (num > 0 ? '+' : '') + num //add plus sign
+    return 'etc/gmt' + num
+  }
+  return null
+}
+
+const parseOffset = function (tz) {
+  // '+5hrs'
+  let m = tz.match(isOffset)
+  if (m !== null) {
+    return toIana(m[1])
+  }
+  // 'utc+5'
+  m = tz.match(utcOffset)
+  if (m !== null) {
+    return toIana(m[1])
+  }
+  // 'GMT-5' (not opposite)
+  m = tz.match(gmtOffset)
+  if (m !== null) {
+    const num = Number(m[1]) * -1
+    return toIana(num)
+  }
+  // '+5'
+  m = tz.match(isNumber)
+  if (m !== null) {
+    return toIana(m[1])
+  }
+  return null
+}
+export default parseOffset