..F....... [ZBX-18957] fixed not displaying years on X axis of classic graphs

Merge in ZBX/zabbix from feature/ZBX-18957-5.0 to release/5.0

* commit 'f595bf2a06151ad1af4f131f0be6cac7cb4531f5':
  ..F....... [ZBX-18957] fixed not displaying years on X axis of classic graphs

(cherry picked from commit 9f69cc0f03e5c3efc65f808cbcf3a7f8a847f4d5)

2 files changed, 16 insertions, 7 deletions

diff --git a/ChangeLog.d/bugfix/ZBX-18957 b/ChangeLog.d/bugfix/ZBX-18957
new file mode 100644
index 00000000000..3e445a962c6
--- /dev/null
+++ b/ChangeLog.d/bugfix/ZBX-18957
@@ -0,0 +1 @@
+..F....... [ZBX-18957] fixed not displaying years on X axis of classic graphs (averza)
diff --git a/ui/include/classes/graphdraw/CLineGraphDraw.php b/ui/include/classes/graphdraw/CLineGraphDraw.php
index a4988b1e782..585fe26262f 100644
--- a/ui/include/classes/graphdraw/CLineGraphDraw.php
+++ b/ui/include/classes/graphdraw/CLineGraphDraw.php
@@ -930,12 +930,14 @@ class CLineGraphDraw extends CGraphDraw {
 	/**
 	 * Get best matching X-axis interval specification for the preferred sub-interval.
 	 *
-	 * @param int   $pref_sub_interval  Preferred sub-interval in seconds.
-	 * @param float $min_sub_interval   Preferred minimal sub-interval in seconds (float). Discarded if no matches.
+	 * @param int    $pref_sub_interval  Preferred sub-interval in seconds.
+	 * @param float  $min_sub_interval   Preferred minimal sub-interval in seconds (float). Discarded if no matches.
+	 * @param string $magnitude          The highest non-permanent date component (Y, m, d, H, i, s).
 	 *
 	 * @return array
 	 */
-	private function getOptimalDateTimeIntervalSpec(int $pref_sub_interval, float $min_sub_interval): array {
+	private function getOptimalDateTimeIntervalSpec(int $pref_sub_interval, float $min_sub_interval,
+			string $magnitude): array {
 		// Possible X-axis main and sub-intervals.
 		$intervals = [
 			'PT1M' => ['PT1S', 'PT5S', 'PT10S', 'PT30S'],
@@ -962,9 +964,9 @@ class CLineGraphDraw extends CGraphDraw {
 		$formats = [
 			'PT1M' => ['main' => TIME_FORMAT, 'sub' => _('H:i:s')],
 			'PT1H' => ['main' => TIME_FORMAT, 'sub' => TIME_FORMAT],
-			'P1D' => ['main' => _('m-d'), 'sub' => TIME_FORMAT],
-			'P1W' => ['main' => _('m-d'), 'sub' => _('m-d')],
-			'P1M' => ['main' => _('m-d'), 'sub' => _('m-d')],
+			'P1D' => ['main' => $magnitude === 'Y' ? DATE_FORMAT : _('m-d'), 'sub' => TIME_FORMAT],
+			'P1W' => ['main' => $magnitude === 'Y' ? DATE_FORMAT : _('m-d'), 'sub' => _('m-d')],
+			'P1M' => ['main' => $magnitude === 'Y' ? DATE_FORMAT : _('m-d'), 'sub' => _('m-d')],
 			'P1Y' => ['main' => _x('Y', DATE_FORMAT_CONTEXT), 'sub' => _('M')],
 			'P10Y' => ['main' => _x('Y', DATE_FORMAT_CONTEXT), 'sub' => _x('Y', DATE_FORMAT_CONTEXT)]
 		];
@@ -1082,7 +1084,13 @@ class CLineGraphDraw extends CGraphDraw {
 
 		$preferred_sub_interval = (int) ($this->period * $this->cell_width / $this->sizeX);
 
-		$optimal = $this->getOptimalDateTimeIntervalSpec($preferred_sub_interval, $label_size);
+		foreach (['Y', 'm', 'd', 'H', 'i', 's'] as $magnitude) {
+			if (date($magnitude, $this->stime) !== date($magnitude, $this->stime + $this->period)) {
+				break;
+			}
+		}
+
+		$optimal = $this->getOptimalDateTimeIntervalSpec($preferred_sub_interval, $label_size, $magnitude);
 
 		// Align starting date and time with the interval.
 		$start = strtotime(date($optimal['aligner']['trim'], $this->stime));