Add more timezones, use 24-hr format, indicate "(next day )" if converted time is +1 day

_includes/head.html

@@ -33,6 +33,6 @@
 
   {% seo %}
 
-  {% include head_custom.html %}
+  {% include timezone_converter.html %}
 
 </head>

_includes/timezone_converter.html

@@ -0,0 +1,95 @@
+<script>
+    function changeTimezone(toTimezone) {
+        var elems = document.getElementsByClassName("time");
+        for (let i = 0; i < elems.length; i++) {
+            const elem = elems[i];
+            let fromTimezone = elem.dataset.timezone;
+            if (fromTimezone === undefined) {
+                fromTimezone = 'PDT';
+            }
+            if (fromTimezone !== toTimezone) {
+                const timeText = elem.innerHTML;
+                let fromDateText = elem.dataset.date;
+                if (!fromDateText)
+                    fromDateText = "2020-04-13";
+                /* conversion */
+                const [validFromTimezone, utcOffset] = getValidTimezone(fromTimezone);
+                const dateTimeString = reformatTimeString(timeText, fromDateText) + utcOffset;
+                const [validToTimezone,offset] = getValidTimezone(toTimezone);
+                const converted = new Date(dateTimeString).toLocaleString("en-GB", {timeZone: validToTimezone});
+                /* check date of converted time and add (next day) string to result if +1 day */
+                const convertedDateOnly = new Date(dateTimeString).toLocaleString("en-GB", {timeZone: validToTimezone, year:'numeric', month:'2-digit', day:'2-digit'});
+                let toDateText = convertedDateOnly.split('/');
+                toDateText = [toDateText[2], toDateText[1], toDateText[0]].join('-');
+                const newTimeArray = converted.split(" ")[1].split(":");
+                let newTime = newTimeArray[0] + ":" + newTimeArray[1];
+                if (toDateText > fromDateText)
+                    newTime += " (next day)";
+                /* set new value */
+                elem.innerHTML = newTime;
+                elem.dataset.timezone = toTimezone;
+                elem.dataset.date = toDateText;
+            }
+        }
+    }
+
+    /*
+    Convert date time string into a format accepted by Date object
+     */
+    function reformatTimeString(timeString, dateString) {
+        const re = /(\d?\d:\d\d)(am|pm|AM|PM)?( \(next day\))?/;
+        const parsed = timeString.match(re);
+        if (parsed) {
+            const hourMinArray = parsed[1].split(":");
+            let hour = parseInt(hourMinArray[0]);
+            if (parsed[2]) {
+                if (parsed[2].toLowerCase() === "pm") {
+                    if (hour !== 12)
+                        hour += 12;
+                }
+            }
+            const hourString = hour.toString().padStart(2, '0');
+            if (dateString)
+                return dateString + "T" + hourString + ":" + hourMinArray[1];
+            else
+                return "2020-04-13T" + hourString + ":" + hourMinArray[1];
+        }
+        else
+            return null
+    }
+    function getValidTimezone(timezone) {
+        let validTimezone = "";
+        let offset = "";
+        switch (timezone) {
+            case 'PDT':
+                validTimezone = "America/Los_Angeles";
+                offset = "-07:00";
+                break;
+            case 'EDT':
+                validTimezone = "America/New_York";
+                offset = "-04:00";
+                break;
+            case 'CEST':
+                validTimezone = "Europe/Amsterdam";
+                offset = "+02:00";
+                break;
+            case 'CST':
+                validTimezone = "Asia/Hong_Kong";
+                offset = "+08:00";
+                break;
+            case 'MST':
+                validTimezone = "America/Denver";
+                offset = "-06:00";
+                break;
+            case 'BST':
+                validTimezone = "Europe/London";
+                offset = "+01:00";
+                break;
+            case 'IST':
+                validTimezone = "Asia/Kolkata";
+                offset = "+05:30";
+                break;
+        }
+        return [validTimezone, offset];
+    }
+</script>

workshops/EEGLAB_2021_UCSD.md

@@ -29,6 +29,10 @@ Below is a still-provisional program for the 2021 Virtual EEGLAB Workshop (sugge
 <button onclick="changeTimezone('PDT')" style="background-color: #4CAF50; color: white; border: none; padding: 5px 5px; text-align: center;">PDT</button>
 <button onclick="changeTimezone('EDT')" style="background-color: #008CBA; color: white; border: none; padding: 5px 5px; text-align: center;">EDT</button>
 <button onclick="changeTimezone('CEST')" style="background-color:Orange; color: white; border: none; padding: 5px 5px; text-align: center;">CEST</button>
+<button onclick="changeTimezone('CST')" style="background-color: #ebcf34; color: white; border: none; padding: 5px 5px; text-align: center;">CST</button>
+<button onclick="changeTimezone('MST')" style="background-color:#34bdeb; color: white; border: none; padding: 5px 5px; text-align: center;">MST</button>
+<button onclick="changeTimezone('BST')" style="background-color:Grey; color: white; border: none; padding: 5px 5px; text-align: center;">BST</button>
+<button onclick="changeTimezone('IST')" style="background-color:Purple; color: white; border: none; padding: 5px 5px; text-align: center;">IST</button>
 
 ## MONDAY, June 14th (open to all; free registration required)
 
@@ -105,7 +109,7 @@ Below is a still-provisional program for the 2021 Virtual EEGLAB Workshop (sugge
 
 ## WEDNESDAY, June 16th (paid registration required)
 
-- <span style="color: black">7:00am–7:45 – **ICA decomposition PRACTICUM** (Johanna Wagner)</span>
+- <span style="color: black"><span class="time" data-timezone="PDT">7:00am</span>–<span class="time" data-timezone="PDT">7:45</span> – **ICA decomposition PRACTICUM** (Johanna Wagner)</span>
 
 - <span style="color: black"><span class="time" data-timezone="PDT">8:00am</span>–<span class="time" data-timezone="PDT">9:00</span> – **Forward &amp; inverse head modeling** (Zeynep Aakalin Acar)</span>
 
@@ -133,7 +137,7 @@ Below is a still-provisional program for the 2021 Virtual EEGLAB Workshop (sugge
 
 ## THURSDAY, June 17th (paid registration required)
 
-- <span style="color: black">7:00am–7:45 – **ICA clustering PRACTICUM** (Julie Onton)</span>
+- <span style="color: black"><span class="time" data-timezone="PDT">7:00am</span>–<span class="time" data-timezone="PDT">7:45</span> – **ICA clustering PRACTICUM** (Julie Onton)</span>
 
 - <span style="color: black"><span class="time" data-timezone="PDT">8:00am</span>-<span class="time" data-timezone="PDT">9:00</span> – **EEGLAB group analysis** (Arnaud Delorme)</span>