import argparse
import os
import sys

from dotenv import load_dotenv
from google import genai
from google.genai import types
from prompts import system_prompt
from functions.call_function import available_functions, call_function

load_dotenv()
api_key = os.environ.get("GEMINI_API_KEY")
if not api_key:
    raise RuntimeError("API Key not found")

client = genai.Client(api_key=api_key)
parser = argparse.ArgumentParser(description="Chatbot")
parser.add_argument("user_prompt", type=str, help="User prompt")
parser.add_argument("--verbose", action="store_true", help="Enable verbose output")
args = parser.parse_args()
messages = [types.Content(role="user", parts=[types.Part(text=args.user_prompt)])]

for _ in range(10):
    response = client.models.generate_content(
        model="gemini-2.5-flash",
        contents=messages,
        config=types.GenerateContentConfig(
            system_instruction=system_prompt,
            tools=[available_functions],
        ),
    )
    if response.candidates:
       for candidate in response.candidates:
           if candidate.content:
               messages.append(candidate.content)

    if not response.usage_metadata:
        raise RuntimeError("Cannot get usage metadata")
    
    if args.verbose:
        print(f"User prompt: {args.user_prompt}")
        print(f"Prompt tokens: {response.usage_metadata.prompt_token_count}")
        print(f"Response tokens: {response.usage_metadata.candidates_token_count}")
    
    function_calls = response.function_calls
    function_responses = []
    if function_calls:
        for function_call in function_calls:
            function_call_result = call_function(function_call, args.verbose)
            
            if not function_call_result.parts:
                raise Exception("function_call_result.parts list is empty")
            if function_call_result.parts[0].function_response is None:
                raise Exception("FunctionResponse object is equal to None")
            if function_call_result.parts[0].function_response.response is None:
                raise Exception("FunctionResponse object response is equal to None")  
            
            function_responses.append(function_call_result.parts[0])
            if args.verbose:
                print(f"-> {function_call_result.parts[0].function_response.response}")
                
        messages.append(types.Content(role="user", parts=function_responses))
    else:
        break
else:
    print("Maximum iterations reached without a final response")
    sys.exit(1)