error handling in frontend together with validation in backend

frontend/src/services/errorService.ts

@@ -0,0 +1,38 @@
+// frontend/src/services/errorService.ts
+export interface ValidationError {
+  field: string;
+  message: string;
+  value?: any;
+}
+
+export interface ApiError {
+  error: string;
+  details?: ValidationError[];
+  message?: string;
+}
+
+export class ErrorService {
+  static extractValidationErrors(error: any): ValidationError[] {
+    if (error?.details && Array.isArray(error.details)) {
+      return error.details;
+    }
+    
+    // Fallback for different error formats
+    if (error.message && typeof error.message === 'string') {
+      return [{ field: 'general', message: error.message }];
+    }
+    
+    return [{ field: 'general', message: 'An unknown error occurred' }];
+  }
+
+  static getFieldErrors(errors: ValidationError[], fieldName: string): string[] {
+    return errors
+      .filter(error => error.field === fieldName)
+      .map(error => error.message);
+  }
+
+  static getFirstFieldError(errors: ValidationError[], fieldName: string): string | null {
+    const fieldErrors = this.getFieldErrors(errors, fieldName);
+    return fieldErrors.length > 0 ? fieldErrors[0] : null;
+  }
+}

frontend/src/services/scheduling/useScheduling.ts

@@ -1,71 +0,0 @@
-import { useState, useCallback } from 'react';
-import { ScheduleRequest, ScheduleResult } from '../../models/scheduling';
-
-export const useScheduling = () => {
-  const [loading, setLoading] = useState(false);
-  const [error, setError] = useState<string | null>(null);
-  const [result, setResult] = useState<ScheduleResult | null>(null);
-  
-  const generateSchedule = useCallback(async (request: ScheduleRequest) => {
-    setLoading(true);
-    setError(null);
-    
-    try {
-      console.log('📤 Sending scheduling request:', {
-        shiftPlan: request.shiftPlan.name,
-        employees: request.employees.length,
-        availabilities: request.availabilities.length,
-        constraints: request.constraints.length
-      });
-
-      const response = await fetch('/api/scheduling/generate-schedule', {
-        method: 'POST',
-        headers: { 
-          'Content-Type': 'application/json',
-        },
-        body: JSON.stringify(request)
-      });
-      
-      if (!response.ok) {
-        const errorText = await response.text();
-        throw new Error(`Scheduling request failed: ${response.status} ${errorText}`);
-      }
-      
-      const data: ScheduleResult = await response.json();
-      
-      console.log('📥 Received scheduling result:', {
-        success: data.success,
-        assignments: Object.keys(data.assignments).length,
-        violations: data.violations.length,
-        processingTime: data.processingTime
-      });
-      
-      setResult(data);
-      return data;
-    } catch (err) {
-      const errorMessage = err instanceof Error ? err.message : 'Unknown scheduling error';
-      console.error('❌ Scheduling error:', errorMessage);
-      setError(errorMessage);
-      throw err;
-    } finally {
-      setLoading(false);
-    }
-  }, []);
-  
-  const reset = useCallback(() => {
-    setLoading(false);
-    setError(null);
-    setResult(null);
-  }, []);
-  
-  return { 
-    generateSchedule, 
-    loading, 
-    error, 
-    result,
-    reset
-  };
-};
-
-// Export for backward compatibility
-export default useScheduling;