import uuid

from fastapi import HTTPException
from sqlalchemy.ext.asyncio import AsyncSession

from org_settings.models import OrgSettings
from org_settings.serializers import serialize_org_setting

VALID_CATEGORIES = (
    "general",
    "notifications",
    "email_templates",
    "career_portal",
    "branding",
    "security",
    # REQ-ANL-08: holds `analytics.tth_baseline` ({"days": N, "source": "..."}),
    # surfaced by /analytics/kpis/fetch as tth_baseline_* fields.
    "analytics",
)


def _as_uuid(value):
    if value in (None, ""):
        return None
    try:
        return uuid.UUID(str(value))
    except (TypeError, ValueError):
        return None


def _user_id(current_user):
    if not current_user or not current_user.get("id"):
        raise HTTPException(status_code=401, detail="Not authenticated")
    uid = _as_uuid(current_user["id"])
    if uid is None:
        raise HTTPException(status_code=401, detail="Invalid user id")
    return uid


class OrgSetting:
    def __init__(self, session: AsyncSession):
        self.session = session

    async def get_settings(self, category=None):
        if category and category not in VALID_CATEGORIES:
            raise HTTPException(
                status_code=422, detail=f"category must be one of {', '.join(VALID_CATEGORIES)}"
            )
        rows, total = await OrgSettings.fetch_settings(self.session, category=category)
        return [serialize_org_setting(r) for r in rows], total

    async def update_settings(self, payload, current_user):
        items = payload.get("settings") or []
        if not items:
            raise HTTPException(status_code=400, detail="settings is required")
        cleaned = []
        for item in items:
            key = (item.get("key") or "").strip()
            category = (item.get("category") or "").strip()
            if not key:
                raise HTTPException(status_code=422, detail="key is required")
            if category not in VALID_CATEGORIES:
                raise HTTPException(
                    status_code=422, detail=f"category must be one of {', '.join(VALID_CATEGORIES)}"
                )
            cleaned.append({
                "setting_key": key,
                "setting_value": item.get("value"),
                "category": category,
            })
        rows = await OrgSettings.upsert_settings(self.session, cleaned, _user_id(current_user))
        return [serialize_org_setting(r) for r in rows]