import os
from openai import OpenAI
from typing import Optional

class OpenAIClient:
    def __init__(self, api_key: Optional[str] = None):
        self.client = OpenAI(api_key=api_key or os.getenv("OPENAI_API_KEY"))
        self.default_model = "gpt-4o"

    def chat(self, prompt: str, system_instruction: str = "You are the 'Grand Tech Wizard'. You are a master Software Architect, Senior Engineer, API/Webhooks Specialist, and App Builder. You design scalable, secure, and idiomatic technical systems.", model: Optional[str] = None) -> str:
        try:
            response = self.client.chat.completions.create(
                model=model or self.default_model,
                messages=[
                    {"role": "system", "content": system_instruction},
                    {"role": "user", "content": prompt}
                ]
            )
            return response.choices[0].message.content
        except Exception as e:
            return f"Error calling OpenAI API: {str(e)}"