"""
Consent & Scheduling Agent — A2A sub-agent that handles post-recruitment consent
workflow and appointment scheduling. Triggered as a handoff from the Recruitment Agent.

A2A task message format follows the Google A2A spec:
  {"task_id": str, "type": "CONSENT_REQUEST" | "SCHEDULE_REQUEST", "payload": {...}}
"""
import uuid
from datetime import datetime, timedelta
from typing import Optional
from llm_client import chat

# In-memory consent + scheduling store (production: Neo4j or Redis)
_consent_records: dict[str, dict] = {}
_schedule_records: dict[str, dict] = {}


# ── Consent status values ──────────────────────────────────────────────────────

CONSENT_PENDING = "PENDING"
CONSENT_SENT = "SENT"
CONSENT_SIGNED = "SIGNED"
CONSENT_DECLINED = "DECLINED"
CONSENT_EXPIRED = "EXPIRED"


# ── A2A task receiver ──────────────────────────────────────────────────────────

def receive_a2a_task(task: dict) -> dict:
    """
    Entry point for A2A inter-agent handoffs.
    Accepts tasks from the Recruitment Agent and routes to consent or scheduling flows.
    """
    task_type = task.get("type", "")
    payload = task.get("payload", {})
    task_id = task.get("task_id", str(uuid.uuid4()))

    if task_type == "CONSENT_REQUEST":
        return initiate_consent(
            patient_id=payload["patient_id"],
            nct_id=payload["nct_id"],
            trial_title=payload.get("trial_title", ""),
            match_score=payload.get("match_score", 0.0),
            task_id=task_id,
        )
    elif task_type == "SCHEDULE_REQUEST":
        return schedule_screening(
            patient_id=payload["patient_id"],
            nct_id=payload["nct_id"],
            site_city=payload.get("site_city", ""),
            site_state=payload.get("site_state", ""),
            task_id=task_id,
        )
    else:
        return {"error": "UNKNOWN_TASK_TYPE", "task_id": task_id, "received_type": task_type}


# ── Consent flow ───────────────────────────────────────────────────────────────

def initiate_consent(
    patient_id: str,
    nct_id: str,
    trial_title: str,
    match_score: float = 0.0,
    task_id: str | None = None,
) -> dict:
    """Create a consent record and generate the consent document."""
    record_id = task_id or str(uuid.uuid4())
    expires_at = (datetime.utcnow() + timedelta(days=30)).isoformat()

    consent_doc = _generate_consent_document(patient_id, nct_id, trial_title)

    record = {
        "consent_id": record_id,
        "patient_id": patient_id,
        "nct_id": nct_id,
        "trial_title": trial_title,
        "match_score": match_score,
        "status": CONSENT_SENT,
        "consent_document": consent_doc,
        "created_at": datetime.utcnow().isoformat(),
        "expires_at": expires_at,
        "signed_at": None,
        "a2a_source": "recruitment_agent",
    }
    _consent_records[record_id] = record
    return {"consent_id": record_id, "status": CONSENT_SENT, "expires_at": expires_at}


def update_consent_status(consent_id: str, status: str, notes: str = "") -> dict:
    record = _consent_records.get(consent_id)
    if not record:
        return {"error": "CONSENT_NOT_FOUND", "consent_id": consent_id}
    record["status"] = status
    if status == CONSENT_SIGNED:
        record["signed_at"] = datetime.utcnow().isoformat()
    if notes:
        record["notes"] = notes
    # If consent signed, auto-trigger scheduling handoff
    if status == CONSENT_SIGNED:
        _trigger_scheduling_handoff(record)
    return record


def get_consent_record(consent_id: str) -> dict | None:
    return _consent_records.get(consent_id)


def list_consent_records(patient_id: str | None = None) -> list[dict]:
    records = list(_consent_records.values())
    if patient_id:
        records = [r for r in records if r["patient_id"] == patient_id]
    return sorted(records, key=lambda r: r["created_at"], reverse=True)


# ── Scheduling flow ────────────────────────────────────────────────────────────

def schedule_screening(
    patient_id: str,
    nct_id: str,
    site_city: str = "",
    site_state: str = "",
    task_id: str | None = None,
) -> dict:
    """Create a screening appointment slot."""
    appt_id = task_id or str(uuid.uuid4())
    # Default slot: next business weekday at 10am
    proposed_dt = _next_business_day()

    appt = {
        "appointment_id": appt_id,
        "patient_id": patient_id,
        "nct_id": nct_id,
        "site_city": site_city,
        "site_state": site_state,
        "proposed_datetime": proposed_dt,
        "status": "PROPOSED",
        "created_at": datetime.utcnow().isoformat(),
        "a2a_source": "consent_agent",
    }
    _schedule_records[appt_id] = appt
    return {"appointment_id": appt_id, "proposed_datetime": proposed_dt, "status": "PROPOSED"}


def confirm_appointment(appt_id: str) -> dict:
    appt = _schedule_records.get(appt_id)
    if not appt:
        return {"error": "APPOINTMENT_NOT_FOUND"}
    appt["status"] = "CONFIRMED"
    appt["confirmed_at"] = datetime.utcnow().isoformat()
    return appt


def list_appointments(patient_id: str | None = None) -> list[dict]:
    appts = list(_schedule_records.values())
    if patient_id:
        appts = [a for a in appts if a["patient_id"] == patient_id]
    return sorted(appts, key=lambda a: a["created_at"], reverse=True)


# ── Helpers ────────────────────────────────────────────────────────────────────

def _trigger_scheduling_handoff(consent_record: dict):
    """Auto-schedule after consent signed — A2A internal handoff."""
    schedule_screening(
        patient_id=consent_record["patient_id"],
        nct_id=consent_record["nct_id"],
        task_id=f"sched_{consent_record['consent_id']}",
    )


def _next_business_day() -> str:
    dt = datetime.utcnow() + timedelta(days=3)
    while dt.weekday() >= 5:  # skip Sat/Sun
        dt += timedelta(days=1)
    return dt.replace(hour=10, minute=0, second=0, microsecond=0).isoformat() + "Z"


def _generate_consent_document(patient_id: str, nct_id: str, trial_title: str) -> str:
    prompt = f"""Generate a concise, plain-language informed consent document (ICF) for clinical trial participation.

Trial: {trial_title}
NCT ID: {nct_id}
Patient ID: {patient_id}

The document should cover in 4 short sections:
1. What this study is about (2-3 sentences)
2. What you will be asked to do (bullet points)
3. Possible risks and benefits (bullet points)
4. Your rights as a participant (2-3 sentences)

Use plain language (8th grade reading level). End with a signature block."""
    try:
        return chat([{"role": "user", "content": prompt}], temperature=0.3, max_tokens=600)
    except Exception:
        return f"Informed Consent Document\nTrial: {trial_title} ({nct_id})\n\nPlease review this document carefully before signing."


def get_consent_stats() -> dict:
    all_records = list(_consent_records.values())
    return {
        "total": len(all_records),
        "sent": sum(1 for r in all_records if r["status"] == CONSENT_SENT),
        "signed": sum(1 for r in all_records if r["status"] == CONSENT_SIGNED),
        "declined": sum(1 for r in all_records if r["status"] == CONSENT_DECLINED),
        "appointments_scheduled": len(_schedule_records),
    }