import json
import boto3
import os
from typing import Any, Dict
from datetime import datetime


class StepFunctionsClient:
    def __init__(self):
        self.region = os.getenv("AWS_REGION", "us-east-1")
        self.client = boto3.client("stepfunctions", region_name=self.region)

    def start_execution(
        self,
        state_machine_arn: str,
        input_data: Dict[str, Any],
        name: str = None
    ) -> Dict:
        """Start a Step Functions execution."""
        try:
            response = self.client.start_execution(
                stateMachineArn=state_machine_arn,
                name=name,
                input=json.dumps(input_data)
            )
            return {
                "execution_arn": response["executionArn"],
                "start_date": response["startDate"].isoformat()
            }
        except Exception as e:
            return {"error": str(e)}

    def describe_execution(self, execution_arn: str) -> Dict:
        """Get details about a Step Functions execution."""
        try:
            response = self.client.describe_execution(executionArn=execution_arn)
            return {
                "name": response["name"],
                "status": response["status"],
                "start_date": response["startDate"].isoformat(),
                "stop_date": response.get("stopDate", "").isoformat() if response.get("stopDate") else None,
                "input": json.loads(response["input"]),
                "output": json.loads(response.get("output", "{}")),
                "error": response.get("error"),
                "cause": response.get("cause")
            }
        except Exception as e:
            return {"error": str(e)}

    def list_state_machines(self) -> list:
        """List all state machines."""
        try:
            paginator = self.client.get_paginator("list_state_machines")
            machines = []
            for page in paginator.paginate():
                machines.extend(page["stateMachines"])
            return machines
        except Exception as e:
            return {"error": str(e)}

    def get_execution_history(self, execution_arn: str) -> list:
        """Get execution history for a Step Functions execution."""
        try:
            paginator = self.client.get_paginator("get_execution_history")
            events = []
            for page in paginator.paginate(executionArn=execution_arn):
                events.extend(page["events"])
            return events
        except Exception as e:
            return {"error": str(e)}