"""OpenAI Responses API integration."""

from __future__ import annotations

from collections.abc import Iterable

from openai import APIConnectionError, APIStatusError, AuthenticationError, OpenAI, RateLimitError


def format_openai_error(error: Exception) -> str:
    """Return a learner-friendly error message."""
    if isinstance(error, AuthenticationError):
        return (
            "The OpenAI API key was rejected. Please check that OPENAI_API_KEY is "
            "set correctly in Hugging Face Secrets."
        )
    if isinstance(error, RateLimitError):
        return (
            "The request was rate limited or the account may have quota or billing "
            "limits. Please wait briefly, then check OpenAI usage and billing settings."
        )
    if isinstance(error, APIConnectionError):
        return (
            "The app could not reach OpenAI. Please check the network connection and "
            "try again."
        )
    if isinstance(error, APIStatusError):
        status = getattr(error, "status_code", "unknown")
        return (
            f"OpenAI returned an API error with status {status}. Please review the "
            "API key, model name, quota, billing status, and request details."
        )
    return "An unexpected AI service error occurred. Please try again or review the Space logs."


def stream_tutor_response(
    *,
    api_key: str,
    model: str,
    system_instructions: str,
    messages: list[dict[str, str]],
) -> Iterable[str]:
    """Yield text deltas from the current event-based OpenAI Responses API stream."""
    client = OpenAI(api_key=api_key)
    input_messages = [
        {"role": message["role"], "content": message["content"]}
        for message in messages
        if message.get("role") in {"user", "assistant"} and message.get("content")
    ]

    stream = client.responses.create(
        model=model,
        instructions=system_instructions,
        input=input_messages,
        stream=True,
    )

    for event in stream:
        if getattr(event, "type", None) == "response.output_text.delta":
            delta = getattr(event, "delta", "")
            if delta:
                yield delta