# Copyright 2025 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import asyncio
from google.adk.agents import Agent
from google.adk.events import Event
from google.adk.runners import Runner
from google.adk.sessions import InMemorySessionService
from google.genai import types

# --8<-- [start:define_long_running_function]

from typing import Any
from google.adk.tools import LongRunningFunctionTool

# 1. Define the long running function
def ask_for_approval(
    purpose: str, amount: float
) -> dict[str, Any]:
    """Ask for approval for the reimbursement."""
    # create a ticket for the approval
    # Send a notification to the approver with the link of the ticket
    return {'status': 'pending', 'approver': 'Sean Zhou', 'purpose' : purpose, 'amount': amount, 'ticket-id': 'approval-ticket-1'}

def reimburse(purpose: str, amount: float) -> dict[str, Any]:
    """Reimburse the amount of money to the employee."""
    # send the reimbrusement request to payment vendor
    return {'status': 'ok'}

# 2. Wrap the function with LongRunningFunctionTool
long_running_tool = LongRunningFunctionTool(func=ask_for_approval)

# --8<-- [end:define_long_running_function]

# 3. Use the tool in an Agent
file_processor_agent = Agent(
    # Use a model compatible with function calling
    model="gemini-2.0-flash",
    name='reimbursement_agent',
    instruction="""
      You are an agent whose job is to handle the reimbursement process for
      the employees. If the amount is less than $100, you will automatically
      approve the reimbursement.

      If the amount is greater than $100, you will
      ask for approval from the manager. If the manager approves, you will
      call reimburse() to reimburse the amount to the employee. If the manager
      rejects, you will inform the employee of the rejection.
    """,
    tools=[reimburse, long_running_tool]
)


APP_NAME = "human_in_the_loop"
USER_ID = "1234"
SESSION_ID = "session1234"

# Session and Runner
async def setup_session_and_runner():
    session_service = InMemorySessionService()
    session = await session_service.create_session(app_name=APP_NAME, user_id=USER_ID, session_id=SESSION_ID)
    runner = Runner(agent=file_processor_agent, app_name=APP_NAME, session_service=session_service)
    return session, runner

# --8<-- [start: call_reimbursement_tool]

# Agent Interaction
async def call_agent_async(query):

    def get_long_running_function_call(event: Event) -> types.FunctionCall:
        # Get the long running function call from the event
        if not event.long_running_tool_ids or not event.content or not event.content.parts:
            return
        for part in event.content.parts:
            if (
                part
                and part.function_call
                and event.long_running_tool_ids
                and part.function_call.id in event.long_running_tool_ids
            ):
                return part.function_call

    def get_function_response(event: Event, function_call_id: str) -> types.FunctionResponse:
        # Get the function response for the fuction call with specified id.
        if not event.content or not event.content.parts:
            return
        for part in event.content.parts:
            if (
                part
                and part.function_response
                and part.function_response.id == function_call_id
            ):
                return part.function_response

    content = types.Content(role='user', parts=[types.Part(text=query)])
    session, runner = await setup_session_and_runner()

    print("\nRunning agent...")
    events_async = runner.run_async(
        session_id=session.id, user_id=USER_ID, new_message=content
    )


    long_running_function_call, long_running_function_response, ticket_id = None, None, None
    async for event in events_async:
        # Use helper to check for the specific auth request event
        if not long_running_function_call:
            long_running_function_call = get_long_running_function_call(event)
        else:
            _potential_response = get_function_response(event, long_running_function_call.id)
            if _potential_response: # Only update if we get a non-None response
                long_running_function_response = _potential_response
                ticket_id = long_running_function_response.response['ticket-id']
        if event.content and event.content.parts:
            if text := ''.join(part.text or '' for part in event.content.parts):
                print(f'[{event.author}]: {text}')


    if long_running_function_response:
        # query the status of the correpsonding ticket via tciket_id
        # send back an intermediate / final response
        updated_response = long_running_function_response.model_copy(deep=True)
        updated_response.response = {'status': 'approved'}
        async for event in runner.run_async(
          session_id=session.id, user_id=USER_ID, new_message=types.Content(parts=[types.Part(function_response = updated_response)], role='user')
        ):
            if event.content and event.content.parts:
                if text := ''.join(part.text or '' for part in event.content.parts):
                    print(f'[{event.author}]: {text}')
          
# --8<-- [end:call_reimbursement_tool]          

# Note: In Colab, you can directly use 'await' at the top level.
# If running this code as a standalone Python script, you'll need to use asyncio.run() or manage the event loop.
                   
# reimbursement that doesn't require approval
# asyncio.run(call_agent_async("Please reimburse 50$ for meals"))
await call_agent_async("Please reimburse 50$ for meals") # For Notebooks, uncomment this line and comment the above line
# reimbursement that requires approval
# asyncio.run(call_agent_async("Please reimburse 200$ for meals"))
await call_agent_async("Please reimburse 200$ for meals") # For Notebooks, uncomment this line and comment the above line