from __future__ import annotations

import json
from typing import Any, List, Optional, Tuple


def _pick_json_like_text(texts: List[str]) -> str:
    candidates = [t.strip() for t in texts if isinstance(t, str) and t.strip()]
    for t in reversed(candidates):
        s = t.lstrip()
        if s.startswith("{") or s.startswith("["):
            return t
    return candidates[-1] if candidates else ""


def extract_json_string_from_response(resp: Any) -> Tuple[str, Optional[str]]:
    """
    Try to extract a JSON object either from structured 'json' content parts,
    or from text content parts.

    Returns: (raw_json_string, error_message_or_None)
    """
    out_text = getattr(resp, "output_text", None)
    if isinstance(out_text, str) and out_text.strip():
        s = out_text.lstrip()
        if s.startswith("{") or s.startswith("["):
            return out_text, None

    outputs = getattr(resp, "output", None) or []
    texts: List[str] = []

    for item in outputs:
        content = getattr(item, "content", None)
        if content is None and isinstance(item, dict):
            content = item.get("content")
        if not content:
            continue

        for part in content:
            ptype = getattr(part, "type", None)
            if ptype is None and isinstance(part, dict):
                ptype = part.get("type")

            if ptype == "refusal":
                refusal_msg = getattr(part, "refusal", None)
                if refusal_msg is None and isinstance(part, dict):
                    refusal_msg = part.get("refusal")
                return "", f"Model refusal: {refusal_msg}"

            j = getattr(part, "json", None)
            if j is None and isinstance(part, dict):
                j = part.get("json")
            if j is not None:
                try:
                    return json.dumps(j, ensure_ascii=False), None
                except Exception as e:
                    return "", f"Failed to serialize json content part: {e}"

            t = getattr(part, "text", None)
            if t is None and isinstance(part, dict):
                t = part.get("text")
            if isinstance(t, str) and t.strip():
                texts.append(t)

    raw = _pick_json_like_text(texts)
    if raw:
        return raw, None

    return "", "Empty output (no json/text content parts found)"