feat: Add session counting methods for mentors and users; enhance registration queries with related data

imphnen-middleware/src/payment_middleware/mod.rs

@@ -1,6 +1,6 @@
 use axum::{
     body::Body,
-    http::{Request, Response},
+    http::{Request, Response, StatusCode, header::HeaderMap},
 };
 use futures::future::BoxFuture;
 use imphnen_libs::AppState;
@@ -52,8 +52,52 @@ where
         let mut inner = self.inner.clone();
         let _app_state = self.app_state.clone();
         Box::pin(async move {
-            // TODO: Implement payment validation logic here
+            // Payment validation logic
+            // Check for payment-related headers or query parameters
+            let headers = req.headers();
+            
+            // Validate payment token if present
+            if let Some(payment_token) = headers.get("X-Payment-Token") {
+                if let Ok(token_str) = payment_token.to_str() {
+                    // Basic validation: check token format
+                    if !is_valid_payment_token(token_str) {
+                        let error_response = Response::builder()
+                            .status(StatusCode::PAYMENT_REQUIRED)
+                            .body(Body::from("Invalid payment token"))
+                            .unwrap();
+                        return Err(error_response);
+                    }
+                }
+            }
+            
+            // Check if endpoint requires payment verification
+            let uri_path = req.uri().path();
+            if requires_payment_verification(uri_path) {
+                if !headers.contains_key("X-Payment-Token") {
+                    let error_response = Response::builder()
+                        .status(StatusCode::PAYMENT_REQUIRED)
+                        .body(Body::from("Payment required for this endpoint"))
+                        .unwrap();
+                    return Err(error_response);
+                }
+            }
+            
+            // Pass through if payment validation succeeds or not required
             inner.call(req).await
         })
     }
+}
+
+/// Validate payment token format
+fn is_valid_payment_token(token: &str) -> bool {
+    // Basic validation: token should be alphanumeric and at least 16 chars
+    token.len() >= 16 && token.chars().all(|c| c.is_alphanumeric() || c == '-' || c == '_')
+}
+
+/// Check if URI path requires payment verification
+fn requires_payment_verification(path: &str) -> bool {
+    // Premium endpoints that require payment
+    path.contains("/premium/") || 
+    path.contains("/paid/") ||
+    path.contains("/subscription/")
 }