From 27bb6a4bc6e7b9c367dd809bcafe9493e5bee214 Mon Sep 17 00:00:00 2001
From: Laura Hausmann <laura@hausmann.dev>
Date: Fri, 19 May 2023 23:47:05 +0200
Subject: [PATCH] Add magic card identifier '@username' for transaction and
 balance api calls

---
 AfRApay.Web/Controllers/CardController.cs | 27 ++++++++++++++++++++---
 1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/AfRApay.Web/Controllers/CardController.cs b/AfRApay.Web/Controllers/CardController.cs
index f42da20..0e04292 100644
--- a/AfRApay.Web/Controllers/CardController.cs
+++ b/AfRApay.Web/Controllers/CardController.cs
@@ -64,7 +64,7 @@ public class CardController : Controller {
 	/// <summary>
 	/// Creates a transaction that changes the balance of the the user the card is linked to by the specified amount.
 	/// </summary>
-	/// <param name="card">The ID of the card</param>
+	/// <param name="card">The ID of the card (alternatively, magic card identifier @username)</param>
 	/// <param name="ik">Random string (idempotency key) which is consistent across request retries</param>
 	/// <param name="amount">Positive or negative number of cents representing the relative change in balance</param>
 	/// <param name="reader">Type of reader that scanned the card</param>
@@ -104,6 +104,22 @@ public class CardController : Controller {
 			await db.SaveChangesAsync();
 			return Ok(new UserResponse(user));
 		}
+		
+		if (db.Users.Any(p => card.Length > 1 && p.Nickname == card.Substring(1))) {
+			var user = db.Users.First(p => card.Length > 1 && p.Nickname == card.Substring(1));
+			if (ik == "" || ik != user.LastIdempotencyKey) {
+				user.LastIdempotencyKey = ik;
+				switch (user.Balance + amount) {
+					case < -9999: return StatusCode(412, new ErrorResponse("Balance too low!"));
+					case > 99999: return StatusCode(412, new ErrorResponse("Balance too high!"));
+				}
+
+				user.Balance += amount;
+			}
+
+			await db.SaveChangesAsync();
+			return Ok(new UserResponse(user));
+		}
 
 		return NotFound(new ErrorResponse("Unknown card."));
 	}
@@ -111,7 +127,7 @@ public class CardController : Controller {
 	/// <summary>
 	/// Returns the balance of the the user the card is linked to.
 	/// </summary>
-	/// <param name="card">The ID of the card</param>
+	/// <param name="card">The ID of the card (alternatively, magic card identifier @username)</param>
 	/// <param name="reader">Type of reader that scanned the card</param>
 	/// <response code="200">Returns 200 if the request succeeded</response>
 	/// <response code="404">Returns 404 if the card isn't linked to any account</response>
@@ -138,6 +154,11 @@ public class CardController : Controller {
 			return Ok(new UserResponse(user));
 		}
 
+		if (db.Users.Any(p => card.Length > 1 && p.Nickname == card.Substring(1))) {
+			var user = db.Users.First(p => card.Length > 1 && p.Nickname == card.Substring(1));
+			return Ok(new UserResponse(user));
+		}
+
 		return NotFound(new ErrorResponse("Unknown card."));
 	}
 
@@ -157,7 +178,7 @@ public class CardController : Controller {
 		public ErrorResponse GetExamples() => new("No active link process");
 	}
 
-	private Card.CardType GetCardType(string? reader, string cardNumber) => reader switch {
+	private static Card.CardType GetCardType(string? reader, string cardNumber) => reader switch {
 		// these seem not be reliable
 		//"pn532-iso14443a" when cardNumber.Length == 8                                                                  => Card.CardType.NfcMifareClassic,
 		//"pn532-iso14443a" when cardNumber.Length == 12 && cardNumber.EndsWith("0218")                                  => Card.CardType.NfcOvChipkaart,