feat(cg1): implement real BigQuery billing queries in billing_agent.py

ml/billing_agent.py

@@ -1,4 +1,6 @@
 import os
+import datetime
+from google.cloud import bigquery
 from google.cloud import billing
 
 class BillingAgent:
@@ -6,41 +8,100 @@ class BillingAgent:
         self.project_id = os.environ.get("GOOGLE_CLOUD_PROJECT")
         if not self.project_id:
             raise ValueError("GOOGLE_CLOUD_PROJECT environment variable not set.")
+        
+        self.billing_account_id = os.environ.get("BILLING_ACCOUNT_ID")
+        if not self.billing_account_id:
+            raise ValueError("BILLING_ACCOUNT_ID environment variable not set.")
+
+        self.bq_client = bigquery.Client(project=self.project_id)
         self.billing_client = billing.CloudBillingClient()
+        self.billing_table = f"{self.project_id}.billing_export.gcp_billing_export_v1_*"
 
     def get_summary(self):
         """
         Retrieves the billing summary for the last 30 days.
         """
-        # This is a simplified example. The Cloud Billing API does not have a direct
-        # "summary" endpoint. You would typically query for cost data over a time range.
-        # This implementation will be a placeholder.
-        return {
-            "summary": "Billing summary data would be here.",
-            "project_id": self.project_id
-        }
+        query = f"""
+            SELECT
+                service.description as service,
+                SUM(cost) as total_cost
+            FROM `{self.billing_table}`
+            WHERE _PARTITIONTIME >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 30 DAY)
+            GROUP BY 1
+            ORDER BY total_cost DESC
+        """
+        query_job = self.bq_client.query(query)
+        results = query_job.result()
+        
+        summary = []
+        for row in results:
+            summary.append({"service": row.service, "total_cost": row.total_cost})
+            
+        return {"summary": summary}
 
     def get_forecast(self):
         """
         Retrieves a billing forecast based on the last 7 days.
         """
-        # The Cloud Billing API does not provide a direct forecast API.
-        # This would require custom logic to calculate.
-        # This implementation will be a placeholder.
+        # Get total cost for the last 7 days
+        query_last_7_days = f"""
+            SELECT SUM(cost) as total_cost
+            FROM `{self.billing_table}`
+            WHERE _PARTITIONTIME >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 7 DAY)
+        """
+        query_job = self.bq_client.query(query_last_7_days)
+        results = query_job.result()
+        
+        total_cost_last_7_days = 0
+        for row in results:
+            total_cost_last_7_days = row.total_cost or 0
+
+        daily_average = total_cost_last_7_days / 7
+
+        # Calculate remaining days in the month
+        today = datetime.date.today()
+        last_day_of_month = datetime.date(today.year, today.month, 1) + datetime.timedelta(days=32)
+        last_day_of_month = last_day_of_month.replace(day=1) - datetime.timedelta(days=1)
+        remaining_days = (last_day_of_month - today).days
+
+        forecasted_cost = daily_average * remaining_days
+        
+        # Get current month-to-date cost
+        query_mtd = f"""
+            SELECT SUM(cost) as total_cost
+            FROM `{self.billing_table}`
+            WHERE EXTRACT(MONTH FROM _PARTITIONTIME) = EXTRACT(MONTH FROM CURRENT_DATE())
+              AND EXTRACT(YEAR FROM _PARTITIONTIME) = EXTRACT(YEAR FROM CURRENT_DATE())
+        """
+        query_job_mtd = self.bq_client.query(query_mtd)
+        results_mtd = query_job_mtd.result()
+        mtd_cost = 0
+        for row in results_mtd:
+            mtd_cost = row.total_cost or 0
+        
+        total_forecast = mtd_cost + forecasted_cost
+
         return {
-            "forecast": "Billing forecast data would be here.",
-            "project_id": self.project_id
+            "daily_average_last_7_days": daily_average,
+            "month_to_date_cost": mtd_cost,
+            "forecasted_remaining_cost": forecasted_cost,
+            "total_monthly_forecast": total_forecast,
         }
 
     def get_credits(self):
         """
         Retrieves active billing credits.
         """
-        # This is a simplified example. You would need to query for billing account
-        # information and then check for credits.
+        billing_account_name = f"billingAccounts/{self.billing_account_id}"
+        billing_info = self.billing_client.get_billing_account(name=billing_account_name)
+        
+        # This is a simplified representation. The actual credit information might
+        # be structured differently. This is a placeholder for the structure.
         return {
-            "credits": "Billing credits information would be here.",
-            "project_id": self.project_id
+            "billing_account_name": billing_info.name,
+            "display_name": billing_info.display_name,
+            "open": billing_info.open,
+            "credits": "Detailed credit information would require further API calls and parsing."
         }
 
 if __name__ == '__main__':