"""
Analyze service orchestrator (Alpha Terminal).

Implements the plan:
- Quadrants: authority | market | risk | value
- Analyzer registry (plugin-like)
- Open-data-first (null + reason)
"""

from __future__ import annotations

import json
from datetime import datetime, timedelta, timezone

from fastapi import HTTPException, status
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.models.domain_analysis_cache import DomainAnalysisCache
from app.schemas.analyze import AnalyzeResponse, AnalyzeSection
from app.services.analyze.base import AnalyzeContext
from app.services.analyze.registry import get_default_analyzers
from app.services.domain_checker import domain_checker
from app.services.domain_health import get_health_checker


DEFAULT_CACHE_TTL_SECONDS = 60 * 10  # conservative fallback (10m)


def _utcnow() -> datetime:
    return datetime.now(timezone.utc)


def _is_cache_valid(row: DomainAnalysisCache) -> bool:
    ttl = int(row.ttl_seconds or 0)
    if ttl <= 0:
        return False
    computed = row.computed_at
    if computed is None:
        return False
    if computed.tzinfo is None:
        # stored as naive UTC typically
        computed = computed.replace(tzinfo=timezone.utc)
    return computed + timedelta(seconds=ttl) > _utcnow()


async def get_domain_analysis(
    db: AsyncSession,
    domain: str,
    *,
    fast: bool = False,
    refresh: bool = False,
) -> AnalyzeResponse:
    is_valid, error = domain_checker.validate_domain(domain)
    if not is_valid:
        raise HTTPException(status_code=status.HTTP_400_BAD_REQUEST, detail=error)

    norm = domain_checker._normalize_domain(domain)  # internal normalize

    # Cache lookup
    if not refresh:
        row = (
            await db.execute(select(DomainAnalysisCache).where(DomainAnalysisCache.domain == norm))
        ).scalar_one_or_none()
        if row and _is_cache_valid(row):
            payload = json.loads(row.payload_json)
            payload["cached"] = True
            return AnalyzeResponse.model_validate(payload)

    computed_at = _utcnow()

    # Core domain facts via RDAP/DNS/WHOIS (shared input for analyzers)
    check = await domain_checker.check_domain(norm, quick=False)

    # Health is expensive; compute once only when needed
    health = None
    if not fast:
        health = await get_health_checker().check_domain(norm)

    ctx = AnalyzeContext(db=db, domain=norm, computed_at=computed_at, fast=fast, check=check, health=health)

    analyzers = get_default_analyzers()
    ttl = DEFAULT_CACHE_TTL_SECONDS

    # Quadrants per plan (stable ordering)
    quadrants: dict[str, AnalyzeSection] = {
        "authority": AnalyzeSection(key="authority", title="Authority", items=[]),
        "market": AnalyzeSection(key="market", title="Market", items=[]),
        "risk": AnalyzeSection(key="risk", title="Risk", items=[]),
        "value": AnalyzeSection(key="value", title="Value", items=[]),
    }

    for a in analyzers:
        ttl = min(ttl, int(getattr(a, "ttl_seconds", DEFAULT_CACHE_TTL_SECONDS) or DEFAULT_CACHE_TTL_SECONDS))
        contributions = await a.analyze(ctx)
        for c in contributions:
            if c.quadrant in quadrants:
                quadrants[c.quadrant].items.extend(c.items)

    resp = AnalyzeResponse(
        domain=norm,
        computed_at=computed_at,
        cached=False,
        sections=[quadrants["authority"], quadrants["market"], quadrants["risk"], quadrants["value"]],
    )

    # Upsert cache (best-effort)
    payload = resp.model_dump(mode="json")
    payload_json = json.dumps(payload, separators=(",", ":"), ensure_ascii=False)
    existing = (
        await db.execute(select(DomainAnalysisCache).where(DomainAnalysisCache.domain == norm))
    ).scalar_one_or_none()
    if existing:
        existing.payload_json = payload_json
        existing.computed_at = computed_at.replace(tzinfo=None)
        existing.ttl_seconds = int(ttl or DEFAULT_CACHE_TTL_SECONDS)
    else:
        db.add(
            DomainAnalysisCache(
                domain=norm,
                payload_json=payload_json,
                computed_at=computed_at.replace(tzinfo=None),
                ttl_seconds=int(ttl or DEFAULT_CACHE_TTL_SECONDS),
            )
        )

    return resp