Add PDO-activity for reading events from database.

src/pvv/side/dbactivity.php

@@ -0,0 +1,66 @@
+<?php
+namespace pvv\side;
+
+use \DateTimeImmutable;
+use \PDO;
+
+class DBActivity implements RepeatingActivity {
+
+	public function __construct($dsn, $username, $password) {
+		$this->pdo = new PDO($dsn, $username, $password);
+		$this->pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+	}
+
+	public function getNextEventFrom(DateTimeImmutable $date) {
+		$query = 'SELECT name,start,stop,organiser,location FROM events WHERE start > :date ORDER BY start ASC LIMIT 1';
+		return $this->retrieve($date, $query);
+	}
+
+	public function getPreviousEventFrom(DateTimeImmutable $date) {
+		$query = 'SELECT name,start,stop,organiser,location FROM events WHERE start < :date ORDER BY start DESC LIMIT 1';
+		return $this->retrieve($date, $query);
+	}
+
+	private function retrieve($date, $query) {
+		$stmt = $this->pdo->prepare($query);
+		$stmt->execute(['date' => $date->format('Y-m-d H:i:s')]);
+		if ($result = $stmt->fetch(PDO::FETCH_ASSOC)){
+			$ev = new OnceEvent(
+				$result['name'],
+				DateTimeImmutable::createFromFormat('Y-m-d H:i:s', $result['start']),
+				DateTimeImmutable::createFromFormat('Y-m-d H:i:s', $result['stop']),
+				$result['organiser'],
+				$result['location']
+			);
+			return $ev;
+		}
+		return null;
+	}
+
+	public function getName() /* : string */ {
+		return "Database";
+	}
+
+	public function getLocation() /* : Location */ {
+		return "Location";
+	}
+
+	public function getOrganiser() /* : User */ {
+		return "User";
+	}
+
+	/*
+    public function getAllEvents(){
+	global $url, $user,$pass,$db;
+	$events = array();
+	$mysqli = new mysqli($url,$user,$pass,$db);
+	$result = $mysqli->query("SELECT name,start,stop,organiser,location FROM events");
+	while($row = $result->fetch_assoc()){
+	$ev = new OnceEvent($row['name'],$row['start'],$row['stop'],$row['organiser'],$row['location']);
+	array_push($events,$ev);
+	}
+	#array_sort($events);
+	return $events;
+    }
+    */
+}