Fix browser incompatible way of parsing local datetime strings

js/customize-post-date-control.js

@@ -183,8 +183,8 @@
 				return;
 			}
 
-			remainingTime = ( new Date( control.setting.get().post_date ) ).valueOf();
-			remainingTime -= ( new Date( api.Posts.getCurrentTime() ) ).valueOf();
+			remainingTime = api.Posts.parsePostDate( control.setting.get().post_date ).valueOf();
+			remainingTime -= api.Posts.parsePostDate( api.Posts.getCurrentTime() ).valueOf();
 			remainingTime = Math.ceil( remainingTime / 1000 );
 			if ( remainingTime > 0 ) {
 				control.scheduledCountdownContainer.text( control.scheduledCountdownTemplate( { remainingTime: remainingTime } ) );

js/customize-post-status-control.js

@@ -110,15 +110,17 @@
 		 */
 		updateChoices: function updateChoices() {
 			var control = this, data = control.setting.get(), isFuture, postTimestamp, currentTimestamp;
-			postTimestamp = ( new Date( data.post_date ) ).valueOf();
-			currentTimestamp = ( new Date( api.Posts.getCurrentTime() ) ).valueOf();
+			postTimestamp = api.Posts.parsePostDate( data.post_date );
+			currentTimestamp = api.Posts.parsePostDate( api.Posts.getCurrentTime() );
 			isFuture = postTimestamp > currentTimestamp;
 
 			/*
 			 * Account for race condition when saving a post with an empty date
 			 * when server time and client time aren't exactly aligned. If the
 			 * status is publish, and yet the post date is less than 15 seconds
 			 * into the future, consider it as not future.
+			 *
+			 * See also https://github.com/xwp/wp-customize-posts/issues/303
 			 */
 			if ( isFuture && 'publish' === data.post_status && postTimestamp - currentTimestamp < 15 * 1000 ) {
 				isFuture = false;

js/customize-posts.js

@@ -534,13 +534,26 @@
 	component.getCurrentTime = function getCurrentTime() {
 		var currentDate, currentTimestamp, timestampDifferential;
 		currentTimestamp = ( new Date() ).valueOf();
-		currentDate = new Date( component.data.initialServerDate.replace( ' ', 'T' ) );
+		currentDate = component.parsePostDate( component.data.initialServerDate );
 		timestampDifferential = currentTimestamp - component.data.initialClientTimestamp;
 		timestampDifferential += component.data.initialClientTimestamp - component.data.initialServerTimestamp;
 		currentDate.setTime( currentDate.getTime() + timestampDifferential );
 		return component.formatDate( currentDate );
 	};
 
+	/**
+	 * Parse post date string in YYYY-MM-DD HH:MM:SS format (local timezone).
+	 *
+	 * @param {string} postDate Post date string.
+	 * @returns {Date} Parsed date.
+	 */
+	component.parsePostDate = function parsePostDate( postDate ) {
+		var dateParts = _.map( postDate.split( /\D/ ), function( datePart ) {
+			return parseInt( datePart, 10 );
+		} );
+		return new Date( dateParts[0], dateParts[1] - 1, dateParts[2], dateParts[3], dateParts[4], dateParts[5] ); // eslint-disable-line no-magic-numbers
+	};
+
 	/**
 	 * Focus on the control requested from the preview.
 	 *