Add system to retrieve and manage donations in a local database

lib/Payment.php

@@ -0,0 +1,58 @@
+<?
+
+class Payment extends PropertiesBase{
+	public $PaymentId;
+	protected $User = null;
+	public $UserId = null;
+	public $Timestamp;
+	public $ChannelId;
+	public $TransactionId;
+	public $Amount;
+	public $Fee;
+	public $IsRecurring;
+
+	protected function GetUser(): ?User{
+		if($this->User === null && $this->UserId !== null){
+			$this->User = User::Get($this->UserId);
+		}
+
+		return $this->User;
+	}
+
+	public function Create(): void{
+		if($this->UserId === null){
+			// Check if we have to create a new user in the database
+
+			// If the User object isn't null, then check if we already have this user in our system
+			if($this->User !== null && $this->User->Email !== null){
+				$result = Db::Query('select * from Users where Email = ?', [$this->User->Email], 'User');
+
+				if(sizeof($result) == 0){
+					// User doesn't exist, create it now
+					$this->User->Create();
+				}
+				else{
+					// User exists, use their data
+					$this->User = $result[0];
+				}
+
+				$this->UserId = $this->User->UserId;
+			}
+		}
+
+		try{
+			Db::Query('insert into Payments (UserId, Timestamp, ChannelId, TransactionId, Amount, Fee, IsRecurring) values(?, ?, ?, ?, ?, ?, ?);', [$this->UserId, $this->Timestamp, $this->ChannelId, $this->TransactionId, $this->Amount, $this->Fee, $this->IsRecurring]);
+		}
+		catch(PDOException $ex){
+			if($ex->errorInfo[1] == 1062){
+				// Duplicate unique key; transction ID already exists
+				throw new Exceptions\PaymentExistsException();
+			}
+			else{
+				throw $ex;
+			}
+		}
+
+		$this->PaymentId = Db::GetLastInsertedId();
+	}
+}