Enhance money change functionality in EventsWorker: Updated the MoneyChange event effect to include an optional minimum absolute positive value, ensuring that money changes do not result in zero for positive adjustments. Introduced a new SQL query for inserting money history, improving reliability in tracking monetary changes for users.

src/worker/events.rs

@@ -16,6 +16,7 @@ use crate::worker::sql::{
     QUERY_INSERT_NOTIFICATION,
     QUERY_GET_MONEY,
     QUERY_UPDATE_MONEY,
+    QUERY_INSERT_MONEY_HISTORY,
     QUERY_GET_REGION_STOCKS,
     QUERY_GET_USER_STOCKS,
     QUERY_UPDATE_STOCK_CAPACITY,
@@ -67,8 +68,14 @@ pub enum EventType {
 /// Mögliche Effekte, die ein Ereignis haben kann
 #[derive(Debug, Clone)]
 pub enum EventEffect {
-    /// Änderung des Geldes eines Spielers (in Prozent)
-    MoneyChange { probability: f64, min_percent: f64, max_percent: f64 },
+    /// Änderung des Geldes eines Spielers (in Prozent).
+    /// Bei positiver Änderung kann min_absolute_positive einen Mindestbetrag erzwingen (z. B. damit ein „Fund“ nie 0 ist).
+    MoneyChange {
+        probability: f64,
+        min_percent: f64,
+        max_percent: f64,
+        min_absolute_positive: Option<f64>,
+    },
     /// Änderung der Produktionsqualität in einer Region (in Prozentpunkten)
     ProductionQualityChange { probability: f64, min_change: i32, max_change: i32 },
     /// Änderung der Verkaufspreise in einer Region (in Prozent)
@@ -169,6 +176,7 @@ impl EventsWorker {
                         probability: 1.0,
                         min_percent: 5.0,
                         max_percent: 15.0,
+                        min_absolute_positive: Some(1.0), // Fund ist nie 0
                     },
                 ],
             },
@@ -183,6 +191,7 @@ impl EventsWorker {
                         probability: 1.0,
                         min_percent: -10.0,
                         max_percent: -5.0,
+                        min_absolute_positive: None,
                     },
                 ],
             },
@@ -511,13 +520,23 @@ impl EventsWorker {
                     probability,
                     min_percent,
                     max_percent,
+                    min_absolute_positive,
                 } => {
                     if effect_roll < *probability {
                         let percent_change = rng.gen_range(*min_percent..=*max_percent);
                         let current_money = Self::get_current_money(&mut conn, user_id).unwrap_or(0.0);
                         let computed_change = current_money * (percent_change / 100.0);
-                        let absolute_change = Self::apply_money_change(&mut conn, user_id, percent_change)
-                            .unwrap_or(computed_change);
+                        let effective_change = match min_absolute_positive {
+                            Some(min_abs) if percent_change > 0.0 && computed_change < *min_abs => *min_abs,
+                            _ => computed_change,
+                        };
+                        let absolute_change = Self::apply_money_change(
+                            &mut conn,
+                            user_id,
+                            percent_change,
+                            Some(effective_change),
+                        )
+                        .unwrap_or(effective_change);
                         effect_results.push(json!({
                             "type": "money_change",
                             "percent": percent_change,
@@ -1030,19 +1049,18 @@ impl EventsWorker {
         conn: &mut DbConnection,
         user_id: i32,
         percent_change: f64,
+        absolute_override: Option<f64>,
     ) -> Result<f64, DbError> {
         let current_money = Self::get_current_money(conn, user_id)?;
-        let change = current_money * (percent_change / 100.0);
+        let change = absolute_override
+            .unwrap_or_else(|| current_money * (percent_change / 100.0));
         let action = format!("Zufallsereignis: Geldänderung {:.2}%", percent_change);
 
         // Verwende parametrisierte Queries für Sicherheit gegen SQL-Injection
     conn.prepare("update_money_event", QUERY_UPDATE_MONEY)?;
     let _ = conn.execute("update_money_event", &[&user_id, &change, &action])?;
 
-        // Best-effort money_history insert for UI/history visibility.
-        let money_str = format!("{:.2}", change);
-        fn escape_sql_literal(s: &str) -> String { s.replace('\'', "''") }
-        let escaped_action = escape_sql_literal(&action);
+        // money_history für UI/Verlauf: Betrag und Aktion zuverlässig speichern (parametrisiert).
         let create_sql = r#"
             CREATE TABLE IF NOT EXISTS falukant_log.money_history (
                 id BIGSERIAL PRIMARY KEY,
@@ -1054,13 +1072,9 @@ impl EventsWorker {
         "#;
         let _ = conn.query(create_sql);
 
-        let history_sql = format!(
-            "INSERT INTO falukant_log.money_history (user_id, change, action, created_at) VALUES ({uid}, {money}::numeric, '{act}', NOW());",
-            uid = user_id,
-            money = money_str,
-            act = escaped_action
-        );
-        if let Err(err) = conn.query(&history_sql) {
+        let money_str = format!("{:.2}", change);
+        let _ = conn.prepare("insert_money_history", QUERY_INSERT_MONEY_HISTORY);
+        if let Err(err) = conn.execute("insert_money_history", &[&user_id, &money_str, &action]) {
             eprintln!(
                 "[EventsWorker] Warning: inserting money_history failed for user {}: {}",
                 user_id, err