silverstripe-blog/code/widgets/ArchiveWidget.php

<?php

if(class_exists('Widget')) {

	/**
	 * Shows a widget with viewing blog entries
	 * by months or years.
	 *
	 * @package blog
	 */
	class ArchiveWidget extends Widget {

		private static $db = array(
			'DisplayMode' => 'Varchar'
		);

		private static $defaults = array(
			'DisplayMode' => 'month'
		);

		private static $title = 'Browse by Date';

		private static $cmsTitle = 'Blog Archive';

		private static $description =
			'Show a list of months or years in which there are blog posts, and provide links to them.';

		function getCMSFields() {
			$fields = parent::getCMSFields();

			$fields->merge(

				new FieldList(
					new OptionsetField(
						'DisplayMode',
						_t('ArchiveWidget.DispBY', 'Display by'),
						array(
							'month' => _t('ArchiveWidget.MONTH', 'month'),
							'year' => _t('ArchiveWidget.YEAR', 'year')
						)
					)
				)
			);

			$this->extend('updateCMSFields', $fields);

			return $fields;
		}

		function getDates() {
			Requirements::themedCSS('archivewidget');

			$results = new ArrayList();
			$container = BlogTree::current();
			$ids = $container->BlogHolderIDs();

			$stage = Versioned::current_stage();
			$suffix = (!$stage || $stage == 'Stage') ? "" : "_$stage";

			if(method_exists(DB::getConn(), 'formattedDatetimeClause')) {
				$monthclause = DB::getConn()->formattedDatetimeClause('"Date"', '%m');
				$yearclause  = DB::getConn()->formattedDatetimeClause('"Date"', '%Y');
			} else {
				$monthclause = 'MONTH("Date")';
				$yearclause  = 'YEAR("Date")';
			}

			// Changed the WHERE clause from where ParentID to WHERE SiteTree$suffix.ParentID as it was ambiguous.

			if($this->DisplayMode == 'month') {
				$sqlResults = DB::query("
					SELECT DISTINCT CAST($monthclause AS " . DB::getConn()->dbDataType('unsigned integer') . ")
						AS \"Month\",
						$yearclause AS \"Year\"
					FROM \"SiteTree$suffix\" INNER JOIN \"BlogEntry$suffix\"
						ON \"SiteTree$suffix\".\"ID\" = \"BlogEntry$suffix\".\"ID\"
					WHERE \"SiteTree$suffix\".\"ParentID\" IN (" . implode(', ', $ids) . ")
					ORDER BY \"Year\" DESC, \"Month\" DESC;"
				);
			} else {
				$sqlResults = DB::query("
					SELECT DISTINCT $yearclause AS \"Year\" 
					FROM \"SiteTree$suffix\" INNER JOIN \"BlogEntry$suffix\"
						ON \"SiteTree$suffix\".\"ID\" = \"BlogEntry$suffix\".\"ID\"
					WHERE \"SiteTree$suffix\".\"ParentID\" IN (" . implode(', ', $ids) . ")
					ORDER BY \"Year\" DESC"
				);
			}

			if($sqlResults) foreach($sqlResults as $sqlResult) {
				$isMonthDisplay = $this->DisplayMode == 'month';

				$monthVal = (isset($sqlResult['Month'])) ? (int) $sqlResult['Month'] : 1;
				$month = ($isMonthDisplay) ? $monthVal : 1;
				$year = ($sqlResult['Year']) ? (int) $sqlResult['Year'] : date('Y');

				$date = DBField::create_field('Date', array(
					'Day' => 1,
					'Month' => $month,
					'Year' => $year
				));

				if($isMonthDisplay) {
					$link = $container->Link('date') . '/' . $sqlResult['Year'] . '/' . sprintf("%'02d", $monthVal);
				} else {
					$link = $container->Link('date') . '/' . $sqlResult['Year'];
				}

				$results->push(new ArrayData(array(
					'Date' => $date,
					'Link' => $link
				)));
			}

			return $results;
		}
	}

}