v2.2.0: add blackjack with reserved bets and hit/stand/double

1 files changed, 81 insertions, 0 deletions

diff --git a/src/server/database.rs b/src/server/database.rs
index 2a1fc40..99e0dde 100644
--- a/src/server/database.rs
+++ b/src/server/database.rs
@@ -177,3 +177,84 @@ pub fn count_plays(conn: &Connection, username: &str) -> i64 {
     )
     .unwrap_or(0)
 }
+
+/// Reserve a bet before a multi-step hand starts.
+pub fn debit(conn: &mut Connection, username: &str, amount: i64) -> rusqlite::Result<i64> {
+    let tx = conn.transaction()?;
+    let updated = tx.execute(
+        "UPDATE users SET balance = balance - ?1
+         WHERE username = ?2 AND balance >= ?1",
+        params![amount, username],
+    )?;
+    if updated != 1 {
+        return Err(rusqlite::Error::QueryReturnedNoRows);
+    }
+    let balance = tx.query_row(
+        "SELECT balance FROM users WHERE username = ?1",
+        [username],
+        |row| row.get(0),
+    )?;
+    tx.commit()?;
+    Ok(balance)
+}
+
+/// Put a reserved bet back (disconnect or cancel).
+pub fn credit(conn: &mut Connection, username: &str, amount: i64) -> rusqlite::Result<i64> {
+    let tx = conn.transaction()?;
+    tx.execute(
+        "UPDATE users SET balance = balance + ?1 WHERE username = ?2",
+        params![amount, username],
+    )?;
+    let balance = tx.query_row(
+        "SELECT balance FROM users WHERE username = ?1",
+        [username],
+        |row| row.get(0),
+    )?;
+    tx.commit()?;
+    Ok(balance)
+}
+
+/// Settle a hand whose bet was already reserved: credit winnings, write the
+/// audit row, and return the new balance.
+#[allow(clippy::too_many_arguments)]
+pub fn settle_play(
+    conn: &mut Connection,
+    session_id: &str,
+    username: &str,
+    game_type: &str,
+    bet_amount: i64,
+    winnings: i64,
+    details: &str,
+) -> rusqlite::Result<i64> {
+    let tx = conn.transaction()?;
+
+    tx.execute(
+        "UPDATE users SET balance = balance + ?1 WHERE username = ?2",
+        params![winnings, username],
+    )?;
+
+    let balance_after: i64 = tx.query_row(
+        "SELECT balance FROM users WHERE username = ?1",
+        [username],
+        |row| row.get(0),
+    )?;
+
+    tx.execute(
+        "INSERT INTO plays
+            (session_id, username, game_type, bet_amount, winnings,
+             balance_after, details)
+         VALUES (?1, ?2, ?3, ?4, ?5, ?6, ?7)",
+        params![
+            session_id,
+            username,
+            game_type,
+            bet_amount,
+            winnings,
+            balance_after,
+            details
+        ],
+    )?;
+
+    tx.commit()?;
+    Ok(balance_after)
+}