feat: 반품관리 페이지 추가

backend/app.py

@@ -5234,6 +5234,158 @@ def api_kims_log_detail(log_id):
         return jsonify({'success': False, 'error': str(e)})
 
 
+# ─────────────────────────────────────────────────────────────
+# 반품 후보 관리
+# ─────────────────────────────────────────────────────────────
+@app.route('/admin/return-management')
+def admin_return_management():
+    """반품 후보 관리 페이지"""
+    return render_template('admin_return_management.html')
+
+
+@app.route('/api/return-candidates')
+def api_return_candidates():
+    """반품 후보 목록 조회 API"""
+    status = request.args.get('status', '')
+    urgency = request.args.get('urgency', '')
+    search = request.args.get('search', '')
+    sort = request.args.get('sort', 'months_desc')
+    
+    try:
+        db_path = os.path.join(BACKEND_DIR, 'db', 'orders.db')
+        conn = sqlite3.connect(db_path)
+        conn.row_factory = sqlite3.Row
+        cursor = conn.cursor()
+        
+        # 기본 쿼리
+        query = "SELECT * FROM return_candidates WHERE 1=1"
+        params = []
+        
+        # 상태 필터
+        if status:
+            query += " AND status = ?"
+            params.append(status)
+        
+        # 검색어 필터
+        if search:
+            query += " AND (drug_name LIKE ? OR drug_code LIKE ?)"
+            params.extend([f'%{search}%', f'%{search}%'])
+        
+        # 긴급도 필터
+        if urgency == 'critical':
+            query += " AND (months_since_use >= 36 OR months_since_purchase >= 36)"
+        elif urgency == 'warning':
+            query += " AND ((months_since_use >= 24 OR months_since_purchase >= 24) AND (COALESCE(months_since_use, 0) < 36 AND COALESCE(months_since_purchase, 0) < 36))"
+        elif urgency == 'normal':
+            query += " AND (COALESCE(months_since_use, 0) < 24 AND COALESCE(months_since_purchase, 0) < 24)"
+        
+        # 정렬
+        sort_map = {
+            'months_desc': 'COALESCE(months_since_use, months_since_purchase, 0) DESC',
+            'months_asc': 'COALESCE(months_since_use, months_since_purchase, 0) ASC',
+            'stock_desc': 'current_stock DESC',
+            'name_asc': 'drug_name ASC',
+            'detected_desc': 'detected_at DESC'
+        }
+        query += f" ORDER BY {sort_map.get(sort, 'detected_at DESC')}"
+        
+        cursor.execute(query, params)
+        rows = cursor.fetchall()
+        
+        items = []
+        for row in rows:
+            items.append({
+                'id': row['id'],
+                'drug_code': row['drug_code'],
+                'drug_name': row['drug_name'],
+                'current_stock': row['current_stock'],
+                'last_prescription_date': row['last_prescription_date'],
+                'months_since_use': row['months_since_use'],
+                'last_purchase_date': row['last_purchase_date'],
+                'months_since_purchase': row['months_since_purchase'],
+                'status': row['status'],
+                'decision_reason': row['decision_reason'],
+                'detected_at': row['detected_at'],
+                'updated_at': row['updated_at']
+            })
+        
+        # 통계 계산
+        cursor.execute("SELECT COUNT(*) FROM return_candidates WHERE months_since_use >= 36 OR months_since_purchase >= 36")
+        critical = cursor.fetchone()[0]
+        
+        cursor.execute("""SELECT COUNT(*) FROM return_candidates 
+            WHERE (months_since_use >= 24 OR months_since_purchase >= 24) 
+            AND (COALESCE(months_since_use, 0) < 36 AND COALESCE(months_since_purchase, 0) < 36)""")
+        warning = cursor.fetchone()[0]
+        
+        cursor.execute("SELECT COUNT(*) FROM return_candidates WHERE status = 'pending'")
+        pending = cursor.fetchone()[0]
+        
+        cursor.execute("SELECT COUNT(*) FROM return_candidates WHERE status IN ('returned', 'keep', 'disposed', 'resolved')")
+        processed = cursor.fetchone()[0]
+        
+        cursor.execute("SELECT COUNT(*) FROM return_candidates")
+        total = cursor.fetchone()[0]
+        
+        conn.close()
+        
+        return jsonify({
+            'success': True,
+            'items': items,
+            'stats': {
+                'critical': critical,
+                'warning': warning,
+                'pending': pending,
+                'processed': processed,
+                'total': total
+            }
+        })
+        
+    except Exception as e:
+        return jsonify({'success': False, 'error': str(e)}), 500
+
+
+@app.route('/api/return-candidates/<int:item_id>', methods=['PUT'])
+def api_update_return_candidate(item_id):
+    """반품 후보 상태 변경 API"""
+    try:
+        data = request.get_json()
+        new_status = data.get('status')
+        reason = data.get('reason', '')
+        
+        if not new_status:
+            return jsonify({'success': False, 'error': '상태가 지정되지 않았습니다'}), 400
+        
+        valid_statuses = ['pending', 'reviewed', 'returned', 'keep', 'disposed', 'resolved']
+        if new_status not in valid_statuses:
+            return jsonify({'success': False, 'error': f'유효하지 않은 상태: {new_status}'}), 400
+        
+        db_path = os.path.join(BACKEND_DIR, 'db', 'orders.db')
+        conn = sqlite3.connect(db_path)
+        cursor = conn.cursor()
+        
+        cursor.execute("""
+            UPDATE return_candidates 
+            SET status = ?, 
+                decision_reason = ?,
+                reviewed_at = datetime('now', 'localtime'),
+                updated_at = datetime('now', 'localtime')
+            WHERE id = ?
+        """, (new_status, reason, item_id))
+        
+        if cursor.rowcount == 0:
+            conn.close()
+            return jsonify({'success': False, 'error': '항목을 찾을 수 없습니다'}), 404
+        
+        conn.commit()
+        conn.close()
+        
+        return jsonify({'success': True, 'message': '상태가 변경되었습니다'})
+        
+    except Exception as e:
+        return jsonify({'success': False, 'error': str(e)}), 500
+
+
 @app.route('/api/kims/interaction-check', methods=['POST'])
 def api_kims_interaction_check():
     """