4 files changed, 38 insertions, 9 deletions

diff --git a/REFERENCE.md b/REFERENCE.md
new file mode 100644
index 0000000..d57378d
--- /dev/null
+++ b/REFERENCE.md
@@ -0,0 +1,5 @@
+# Reference
+
+- Don't know where to start? Gradecoin uses RESTful API, simple `curl` commands or even your browser will work! [This website will help as well](https://curl.trillworks.com/).
+- [JWT Debugger](https://jwt.io) and the corresponding [RFC](https://tools.ietf.org/html/rfc7519)
+
diff --git a/TODO.md b/TODO.md
index 1e909cd..b429097 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,8 +1,5 @@
 # TODO
 
-## Simulation
-- [ ] Bank mechanism should be added.
-
 ## Tests
 - [ ] User Authentication/Authentication Tests
 - [ ] Route Tests
@@ -36,3 +33,4 @@
 - [.] POST requests to /block should be authenticated as well (2021-04-13 04:50, they now are but until we make error messages **Verbose** there's not much point in testing because I honestly cannot trace the code)
 - [X] Blocks should "play out" the transactions and execute transactions (2021-04-14 21:29)
 - [X] "Coinbase" ("by" of the first transaction of the block) should get rewarded for their efforts (2021-04-14 21:48)
+- [X] Implemented Bank Account (2021-04-14 23:28)
diff --git a/src/handlers.rs b/src/handlers.rs
index 90cc8c4..a8c9947 100644
--- a/src/handlers.rs
+++ b/src/handlers.rs
@@ -420,7 +420,6 @@ pub async fn authorized_propose_block(
 /// * `token` - An Authorization header value such as `Bearer aaa.bbb.ccc`
 /// * `db` - Global [`Db`] instance
 ///
-/// TODO This method should check if the user has enough balance for the transaction
 pub async fn authorized_propose_transaction(
     new_transaction: Transaction,
     token: String,
@@ -459,17 +458,30 @@ pub async fn authorized_propose_transaction(
             return Ok(warp::reply::with_status(
                 warp::reply::json(&GradeCoinResponse {
                     res: ResponseType::Error,
-                    message: "User does not have enough balance in their account".to_owned(),
+                    message:
+                        "User does not have enough balance in their account for this transaction"
+                            .to_owned(),
                 }),
                 StatusCode::BAD_REQUEST,
             ));
         }
+    } else if new_transaction.by == new_transaction.target
+        && new_transaction.source
+            != "31415926535897932384626433832795028841971693993751058209749445923"
+    {
+        // Propose to transact with the bank
+        return Ok(warp::reply::with_status(
+            warp::reply::json(&GradeCoinResponse {
+                res: ResponseType::Error,
+                message: "Transactions cannot extort Gradecoin from unsuspecting users".to_owned(),
+            }),
+            StatusCode::BAD_REQUEST,
+        ));
     } else {
-        // TODO: add bank mechanism <14-04-21, keles> //
         return Ok(warp::reply::with_status(
             warp::reply::json(&GradeCoinResponse {
                 res: ResponseType::Error,
-                message: "Invalid by field for the proposed transaction".to_owned(),
+                message: "Transactions cannot be proposed between two unrelated parties".to_owned(),
             }),
             StatusCode::BAD_REQUEST,
         ));
diff --git a/src/schema.rs b/src/schema.rs
index c740bf3..af10b4d 100644
--- a/src/schema.rs
+++ b/src/schema.rs
@@ -93,15 +93,28 @@ pub struct Claims {
 pub struct Db {
     pub blockchain: Arc<RwLock<Block>>,
     pub pending_transactions: Arc<RwLock<HashMap<Fingerprint, Transaction>>>,
-    pub users: Arc<RwLock<HashMap<String, User>>>,
+    pub users: Arc<RwLock<HashMap<Fingerprint, User>>>,
 }
 
 impl Db {
     fn new() -> Self {
+        let mut users: HashMap<Fingerprint, User> = HashMap::new();
+
+        let bank_acc = MetuId::new("bank".to_owned(), "P7oxDm30g1jeIId".to_owned()).unwrap();
+
+        users.insert(
+            "31415926535897932384626433832795028841971693993751058209749445923".to_owned(),
+            User {
+                user_id: bank_acc,
+                public_key: "null".to_owned(),
+                balance: 27 * 80,
+            },
+        );
+
         Db {
             blockchain: Arc::new(RwLock::new(Block::new())),
             pending_transactions: Arc::new(RwLock::new(HashMap::new())),
-            users: Arc::new(RwLock::new(HashMap::new())),
+            users: Arc::new(RwLock::new(users)),
         }
     }
 }
@@ -216,6 +229,7 @@ lazy_static! {
             ("e223786", "UxI6czykJfp9T9N"),
             ("e231060", "VJgziofQQPCoisH"),
             ("e223795", "pmcTCKox99NFsqp"),
+            ("bank", "P7oxDm30g1jeIId"),
         ]
         .iter()
         .cloned()