"""Employment response decorators for `parse_employment_response`.

Pure module: no FastAPI imports, no HTTPException, and no module-level state.
Mirrors job/candidate/decorators.py — stacked wrappers that clean LLM output
before the task persists it:

    raw JSON -> require_json_object -> clamp_company_to_resume
              -> clamp_education_to_resume -> parse_employment_response
"""

from __future__ import annotations

from functools import wraps

from employment_agent.prompt import EDUCATION,NO_COMPANY


def require_json_object(func):
    """Reject non-dict LLM payloads before field parsing runs."""

    @wraps(func)
    def wrapper(data,resume_text="",*args,**kwargs):
        if not isinstance(data,dict):
            raise RuntimeError(f"model did not return a JSON object: {data!r}")
        return func(data,resume_text,*args,**kwargs)

    return wrapper


def clamp_company_to_resume(func):
    """Keep company only when it appears in resume_text; else NO_COMPANY."""

    @wraps(func)
    def wrapper(data,resume_text="",*args,**kwargs):
        company,education,current_title=func(data,resume_text,*args,**kwargs)
        company=(company or "").strip()
        if not company or company.lower()==NO_COMPANY.lower():
            return NO_COMPANY,education,current_title
        haystack=(resume_text or "").lower()
        if company.lower() not in haystack:
            return NO_COMPANY,education,current_title
        return company,education,current_title

    return wrapper


def clamp_education_to_resume(func):
    """Keep education only when it appears in resume_text; else EDUCATION."""

    @wraps(func)
    def wrapper(data,resume_text="",*args,**kwargs):
        company,education,current_title=func(data,resume_text,*args,**kwargs)
        education=(education or "").strip()
        if not education or education.lower()==EDUCATION.lower():
            return company,EDUCATION,current_title
        haystack=(resume_text or "").lower()
        if education.lower() not in haystack:
            return company,EDUCATION,current_title
        return company,education,current_title

    return wrapper


@require_json_object
@clamp_company_to_resume
@clamp_education_to_resume
def parse_employment_response(data,resume_text:str="") -> tuple[str,str]:
    """Pull company + education from LLM JSON; decorators clamp to the resume."""
    current=data.get("current_employment")
    education=data.get("education")
    current_title=data.get("current_title")
    if not isinstance(current,str):
        current=""
    if not isinstance(education,str):
        education=""
    if not isinstance(current_title,str):
        current_title=""
    return current.strip(),education.strip(),current_title.strip()