import json
import time
import typing

from agent_server.openai_schemas import ChatMessage


def normalize_content_to_text(content: typing.Any) -> str:
    if isinstance(content, str):
        return content
    if isinstance(content, (bytes, bytearray)):
        try:
            return content.decode("utf-8", errors="ignore")
        except Exception:
            return str(content)
    if isinstance(content, list):
        parts = []
        for item in content:
            if (
                isinstance(item, dict)
                and item.get("type") == "text"
                and isinstance(item.get("text"), str)
            ):
                parts.append(item["text"])
            else:
                try:
                    parts.append(json.dumps(item, ensure_ascii=False))
                except Exception:
                    parts.append(str(item))
        return "\n".join(parts)
    if isinstance(content, dict):
        try:
            return json.dumps(content, ensure_ascii=False)
        except Exception:
            return str(content)
    return str(content)


def messages_to_task(messages: typing.List[ChatMessage]) -> str:
    system_parts = [
        normalize_content_to_text(m.get("content", ""))
        for m in messages
        if m.get("role") == "system"
    ]
    user_parts = [
        normalize_content_to_text(m.get("content", ""))
        for m in messages
        if m.get("role") == "user"
    ]
    assistant_parts = [
        normalize_content_to_text(m.get("content", ""))
        for m in messages
        if m.get("role") == "assistant"
    ]

    sys_txt = "\n".join([s for s in system_parts if s]).strip()
    history = ""
    if assistant_parts:
        history = "\n\nPrevious assistant replies (for context):\n" + "\n---\n".join(
            assistant_parts
        )

    last_user = user_parts[-1] if user_parts else ""

    return f"{sys_txt}\nTask:\n{last_user}\n{history}".strip()


def openai_response(message_text: str, model_name: str) -> typing.Dict[str, typing.Any]:
    now = int(time.time())
    return {
        "id": f"chatcmpl-smol-{now}",
        "object": "chat.completion",
        "created": now,
        "model": model_name,
        "choices": [
            {
                "index": 0,
                "message": {"role": "assistant", "content": message_text},
                "finish_reason": "stop",
            }
        ],
        "usage": {"prompt_tokens": 0, "completion_tokens": 0, "total_tokens": 0},
    }


def sse_headers() -> dict:
    return {
        "Cache-Control": "no-cache, no-transform",
        "Connection": "keep-alive",
        "X-Accel-Buffering": "no",
    }


def now_ts() -> int:
    return int(time.time())