import requests
import os

class ExternalModelService:
    def generate(self, provider: str, model: str, prompt: str):
        if provider == "openai":
            return self.openai(model, prompt)

        if provider == "anthropic":
            return self.anthropic(model, prompt)

        if provider == "mistral":
            return self.mistral(model, prompt)

        return "Erro: provider desconhecido."

    def openai(self, model, prompt):
        url = "https://api.openai.com/v1/chat/completions"
        headers = {"Authorization": f"Bearer {os.getenv('OPENAI_API_KEY')}"}
        payload = {
            "model": model,
            "messages": [{"role": "user", "content": prompt}]
        }
        r = requests.post(url, json=payload, headers=headers)
        return r.json()["choices"][0]["message"]["content"]

    def anthropic(self, model, prompt):
        url = "https://api.anthropic.com/v1/messages"
        headers = {"x-api-key": os.getenv("ANTHROPIC_API_KEY")}
        payload = {
            "model": model,
            "max_tokens": 4096,
            "messages": [{"role": "user", "content": prompt}]
        }
        r = requests.post(url, json=payload, headers=headers)
        return r.json()["content"][0]["text"]

    def mistral(self, model, prompt):
        url = "https://api.mistral.ai/v1/chat/completions"
        headers = {"Authorization": f"Bearer {os.getenv('MISTRAL_API_KEY')}"}
        payload = {
            "model": model,
            "messages": [{"role": "user", "content": prompt}]
        }
        r = requests.post(url, json=payload, headers=headers)
        return r.json()["choices"][0]["message"]["content"]