"""Agent graph node logic.

Pure module: no FastAPI imports and no HTTPException.
LLM client/config lives in llm_setup — nodes call llm_call only.
"""

from __future__ import annotations

import logging
from typing import Literal

from langgraph.graph import END

from agent.decorators import normalize_job_posts,parse_match_response
from agent.models import AgentState
from agent.prompt import prompt,user_prompt
from llm_setup import llm_call

logger=logging.getLogger("agent")


async def prepare_context(state:AgentState) -> dict:
    subject=(state.get("subject") or "").strip()
    resume_text=(state.get("resume_text") or "").strip()
    job_posts=normalize_job_posts(state.get("job_posts"))

    if not resume_text:
        return {"status":"skipped","error":"resume_text is empty","suggested_job_post_ids":[]}
    if not job_posts:
        return {"status":"skipped","error":"no active job posts to match against","suggested_job_post_ids":[]}

    return {
        "subject":subject,
        "resume_text":resume_text,
        "job_posts":job_posts,
        "status":"ready",
        "error":"",
    }


def route_after_prepare(state:AgentState) -> Literal["match_jobs","__end__"]:
    if state.get("status")=="ready":
        return "match_jobs"
    return END


async def match_jobs(state:AgentState) -> dict:
    try:
        data=await llm_call(prompt(),user_prompt(state),json_mode=True)
        allowed_ids={item["id"] for item in state.get("job_posts") or []}
        suggested,summary,reasoning,experience=parse_match_response(data,allowed_ids)
        return {
            "status":"matched",
            "suggested_job_post_ids":suggested,
            "summary":summary,
            "reasoning":reasoning,
            "experience":experience,
        }
    except Exception as e:
        logger.exception("agent match_jobs failed")
        return {
            "status":"failed",
            "error":str(e),
            "suggested_job_post_ids":[],
            "summary":"",
            "reasoning":"",
            "experience":"",
        }