from __future__ import annotations

import time

from ..state import AgentState
from ..models import LLMClient, WRITER_PROMPT_TEMPLATE
from ..tools import get_logger, log_state_summary

logger = get_logger()


def writer_node(state: AgentState) -> AgentState:
    start = time.time()
    topic = state.get("topic", "")
    snippets = state.get("research_snippets", []) or []

    joined_snippets = "\n\n".join(
        f"- {s['snippet']} (source: {s['title']} – {s['url']})" for s in snippets
    )

    client = LLMClient()

    system_prompt = "You are a precise and structured writer who follows instructions carefully."
    user_prompt = WRITER_PROMPT_TEMPLATE.format(topic=topic, snippets=joined_snippets)

    logger.info("Writer: generating first draft...")
    draft = client.generate(system_prompt=system_prompt, user_prompt=user_prompt)

    meta = state.get("meta", {}) or {}
    meta["writer_time_sec"] = round(time.time() - start, 3)

    new_state: AgentState = {
        **state,
        "draft": draft,
        "meta": meta,
    }
    log_state_summary(new_state, prefix="Writer")
    return new_state