"""SNS 초안·승인·게시. 일반 발행과 분리해 사장님의 명시적인 요청만 처리한다."""

import hashlib
import json
from config import social_config as config
import secrets
from datetime import datetime, timedelta, timezone
from uuid import UUID

import httpx
from fastapi import HTTPException
from sqlalchemy import select, update, text
from sqlalchemy.dialects.postgresql import insert

from common.database.model.models import (
    place_social_posts as Post,
    sites,
    places,
    place_facts,
    owner_social_accounts as Account,
)
from common.enums import SiteStatus, ErrorType, PUBLISHABLE_FACT_STATUSES
from crud.place_crud import PlaceCRUD
from crud import social_crud as db
from services import site_payload, social_account_service as accounts
from services.external import gemini_text
from services.external.social import (
    SocialError,
    SocialOutcomeUnknown,
    adapter,
    weighted_length,
)


def sha(token):
    return hashlib.sha256(token.encode()).hexdigest()


def public_post(row):
    return {
        "account_bound": bool(row.account_id),
        **{
            key: (str(value) if isinstance(value, UUID) else value)
            for key in (
                "post_id",
                "provider",
                "body",
                "link_url",
                "status",
                "approval_expires_at",
                "approval_channel",
                "permalink",
                "posted_at",
                "last_error",
            )
            if (value := getattr(row, key)) is not None
        },
    }


async def owned_place(s, user_id, place_id):
    err, place = await PlaceCRUD().get_place(s, UUID(str(user_id)), UUID(str(place_id)))
    if err != ErrorType.SUCCESS or not place:
        raise HTTPException(404, "PLACE_NOT_FOUND")
    return place


async def target(s, user_id, place_id):
    place = await owned_place(s, user_id, place_id)
    site = (
        await s.execute(
            select(sites)
            .where(sites.place_id == place.place_id, sites.deleted == False)
            .with_for_update()
        )
    ).scalar_one_or_none()  # noqa: E712
    if (
        not site
        or site.status != SiteStatus.PUBLISHED.value
        or not site.current_version_id
        or not site.domain
    ):
        raise HTTPException(409, "SOCIAL_PUBLISHED_FIXED_URL_REQUIRED")
    return (
        place,
        site,
        site_payload.publish_origin() + "/s/" + site_payload.publish_slug(place, site),
    )


async def list_posts(user_id, place_id):
    async def run(s):
        await owned_place(s, user_id, place_id)
        rows = (
            (
                await s.execute(
                    select(Post)
                    .where(
                        Post.place_id == place_id,
                        Post.user_id == user_id,
                        Post.deleted == False,
                    )
                    .order_by(Post.created_at.desc())
                    .limit(20)
                )
            )
            .scalars()
            .all()
        )  # noqa: E712
        account = await accounts.account(s, user_id, 2)
        return {
            "posts": [public_post(r) for r in rows],
            "connection_enabled": accounts.configured(),
            "posting_enabled": posting_enabled(),
            "account": (
                {
                    "handle": account.handle,
                    "profile_url": account.profile_url,
                    "status": account.status,
                }
                if account
                else None
            ),
        }

    return await db.transaction(run)


async def account_state(user_id, provider=2):
    """사장님의 SNS 계정 연결 상태. **사업장과 무관하다.**

    ★ 왜 place 경로와 따로 두나 — 계정은 `user × provider` 단위라(표도 그렇게 생겼다)
      사이트마다 물어볼 값이 아니다. 연결 화면이 사업장 안에 있으면 사장님은 업장 수만큼
      연결해야 하는 줄 안다. 연결은 한 번, 게재는 사이트마다다.
    """
    async def run(s):
        row = await accounts.account(s, user_id, provider)
        return {
            "connection_enabled": accounts.configured(provider),
            "posting_enabled": posting_enabled(),
            "account": ({"handle": row.handle, "profile_url": row.profile_url,
                         "status": row.status} if row else None),
        }
    return await db.transaction(run)


def posting_enabled():
    # 플랫폼 계약과 해지 안내 페이지 정책을 운영에서 확인한 뒤 명시적으로 연다.
    return accounts.configured() and config.get("SOCIAL_POSTING_ENABLED") == "1"


async def create_draft(user_id, place_id, provider=2):
    async def run(s):
        place, site, url = await target(s, user_id, place_id)
        rows = (
            (
                await s.execute(
                    select(place_facts).where(
                        place_facts.place_id == place.place_id,
                        place_facts.deleted == False,  # noqa: E712
                        place_facts.status.in_(
                            [v.value for v in PUBLISHABLE_FACT_STATUSES]
                        ),
                        (
                            place_facts.expires_at.is_(None)
                            | (place_facts.expires_at > datetime.now(timezone.utc))
                        ),
                    )
                )
            )
            .scalars()
            .all()
        )
        facts = [
            {
                "key": r.key,
                "value": r.value,
                "fact_id": str(r.fact_id),
                "unit": r.unit,
                "source_url": r.source_url,
            }
            for r in rows
            if r.value and r.value.strip() and r.key != "meta_description"
        ]
        if not facts:
            raise HTTPException(409, "NO_GROUNDED_FACTS")
        row_id = (
            await s.execute(
                insert(Post)
                .values(
                    place_id=place_id,
                    user_id=user_id,
                    site_version_id=site.current_version_id,
                    provider=provider,
                    link_url=url,
                    grounded_facts=facts,
                )
                .on_conflict_do_nothing(
                    index_elements=["place_id", "site_version_id"],
                    index_where=text("deleted=false"),
                )
                .returning(Post.post_id)
            )
        ).scalar_one_or_none()
        row = (
            await s.execute(
                select(Post).where(
                    Post.place_id == place_id,
                    Post.site_version_id == site.current_version_id,
                    Post.deleted == False,
                )
            )
        ).scalar_one()  # noqa: E712
        # 생성 실패는 같은 원고 행을 재시도한다. 이미 쓴 글은 유료 재생성하지 않는다.
        if not row_id and row.status == "FAILED" and not row.body:
            row.status, row.last_error = "DRAFTING", None
            row.updated_at = datetime.now(timezone.utc)
            await s.flush()
            row_id = row.post_id
        if row_id:
            await db.enqueue(s, row.post_id, 8)
        return public_post(row)

    return await db.transaction(run)


async def run_draft(job):
    post_id = UUID(job["payload"]["post_id"])

    async def load(s):
        row = await s.get(Post, post_id)
        if not row or row.deleted or row.status != "DRAFTING":
            return None
        place, _, url = await target(s, row.user_id, row.place_id)
        if row.link_url != url:
            raise SocialError("PUBLISH_URL_CHANGED")
        return place.name, row.provider, row.link_url, row.grounded_facts

    try:
        data = await db.transaction(load)
        if not data:
            return {"skipped": True}
        name, provider, url, facts = data
        body = await gemini_text.generate_social_post(
            name,
            [
                gemini_text.FactInput(
                    key=f["key"], label=f["key"], value=f["value"], unit=f.get("unit")
                )
                for f in facts
            ],
            url,
            provider,
        )

        async def save(s):
            await s.execute(
                update(Post)
                .where(Post.post_id == post_id, Post.status == "DRAFTING")
                .values(
                    body=body,
                    status="DRAFT",
                    last_error=None,
                    updated_at=datetime.now(timezone.utc),
                )
            )

        await db.transaction(save)
        return {"post_id": str(post_id)}
    except Exception:
        await set_failure(post_id, "DRAFT_FAILED", expected="DRAFTING")
        raise SocialError("DRAFT_FAILED") from None


async def set_failure(post_id, code, *, expected="POSTING", status="FAILED"):
    async def run(s):
        await s.execute(
            update(Post)
            .where(Post.post_id == post_id, Post.status == expected)
            .values(
                status=status, last_error=code, updated_at=datetime.now(timezone.utc)
            )
        )

    await db.transaction(run)


async def request_approval(user_id, post_id):
    token = secrets.token_urlsafe(32)

    async def run(s):
        initial = await s.get(Post, post_id)
        if not initial or initial.deleted or initial.user_id != user_id:
            raise HTTPException(404, "PLACE_NOT_FOUND")
        _, _, url = await target(s, user_id, initial.place_id)
        # 생성/승인/게시 모두 site → post 순서로 잠근다. 반대면 동시 재요청이 교착된다.
        row = (
            await s.execute(
                select(Post)
                .where(
                    Post.post_id == post_id,
                    Post.user_id == user_id,
                    Post.deleted == False,
                )
                .with_for_update()
                .execution_options(populate_existing=True)
            )
        ).scalar_one()  # noqa: E712
        if row.link_url != url:
            raise HTTPException(409, "PUBLISH_URL_CHANGED")
        expired = row.approval_expires_at and row.approval_expires_at <= datetime.now(
            timezone.utc
        )
        resendable = row.status == "PENDING_APPROVAL" and (expired or row.last_error)
        reconnectable = row.status == "APPROVED" and row.account_id is None
        if (
            row.status not in ("DRAFT", "EXPIRED", "DECLINED", "FAILED")
            and not resendable
            and not reconnectable
        ) or not row.body:
            return {"post": public_post(row), "already_processed": True}
        account = (
            await accounts.account(s, user_id, row.provider)
            if posting_enabled()
            else None
        )
        if posting_enabled() and (not account or account.status != "linked"):
            raise HTTPException(409, "ACCOUNT_CONNECTION_REQUIRED")
        row.status = "PENDING_APPROVAL"
        row.account_id = account.account_id if account else None
        row.approval_token_sha = sha(token)
        row.approval_channel = "screen"
        row.approval_sent_at = None
        row.approval_expires_at = datetime.now(timezone.utc) + timedelta(
            hours=max(1, min(168, int(config.get("SOCIAL_APPROVAL_HOURS", "24"))))
        )
        row.updated_at = datetime.now(timezone.utc)
        row.last_error = None
        await s.flush()
        return {
            "post": public_post(row),
            "approval_path": f"/approve/{post_id}?t={token}",
        }

    result = await db.transaction(run)
    if result.get("approval_path"):
        from services.notify_service import request_approval as notify

        await notify(post_id, user_id, token, result["approval_path"])
    return result


async def approval(post_id, token, *, approve=None):
    async def run(s):
        row = (
            await s.execute(
                select(Post).where(
                    Post.post_id == post_id,
                    Post.deleted == False,
                    Post.approval_token_sha == sha(token),
                )
            )
        ).scalar_one_or_none()  # noqa: E712
        if not row:
            raise HTTPException(404, "APPROVAL_NOT_FOUND")
        await owned_place(s, row.user_id, row.place_id)
        account = await s.get(Account, row.account_id) if row.account_id else None
        if approve is None:
            result = public_post(row)
            result["account_handle"] = account.handle if account else None
            return result
        if approve and row.status == "PENDING_APPROVAL":
            _, _, url = await target(s, row.user_id, row.place_id)
            if row.link_url != url or (
                row.account_id
                and (not account or account.deleted or account.status != "linked")
            ):
                raise HTTPException(409, "APPROVAL_TARGET_CHANGED")
        applied = await db.decide(s, post_id, sha(token), approve, "link")
        return {
            "applied": applied,
            "message": "승인했습니다"
            if applied and approve
            else "게재하지 않습니다"
            if applied
            else "이미 처리됐거나 만료된 요청입니다",
        }

    return await db.transaction(run)


async def owner_decision(user_id, post_id, approve):
    # 화면은 비밀 링크를 저장하지 않아도 승인할 수 있다. 신원 범위만 다르고 CAS는 같다.
    async def load(s):
        row = await s.get(Post, post_id)
        if not row or row.deleted or row.user_id != user_id:
            raise HTTPException(404, "PLACE_NOT_FOUND")
        await owned_place(s, user_id, row.place_id)
        if approve:
            _, _, url = await target(s, user_id, row.place_id)
            account = await s.get(Account, row.account_id) if row.account_id else None
            if url != row.link_url or (
                row.account_id
                and (not account or account.deleted or account.status != "linked")
            ):
                raise HTTPException(409, "APPROVAL_TARGET_CHANGED")
        return {
            "applied": await db.decide(
                s, post_id, row.approval_token_sha, approve, "builder"
            )
        }

    return await db.transaction(load)


async def run_post(job):
    post_id = UUID(job["payload"]["post_id"])
    if not posting_enabled():
        await set_failure(post_id, "SOCIAL_POSTING_DISABLED", expected="APPROVED")
        raise SocialError("SOCIAL_POSTING_DISABLED")

    async def claim(s):
        return (
            await s.execute(
                update(Post)
                .where(
                    Post.post_id == post_id,
                    Post.deleted == False,  # noqa: E712
                    Post.status == "APPROVED",
                )
                .values(status="POSTING", updated_at=datetime.now(timezone.utc))
                .returning(Post.user_id, Post.provider, Post.account_id)
            )
        ).first()

    claimed = await db.transaction(claim)
    if not claimed:
        return {"skipped": True}
    user_id, provider, account_id = claimed
    async with httpx.AsyncClient(timeout=20) as client:
        try:

            async def refresh(s):
                await accounts.lock_user(s, user_id, provider)
                row = await s.get(Account, account_id)
                if (
                    not row
                    or row.deleted
                    or row.user_id != user_id
                    or row.status != "linked"
                ):
                    raise SocialError("ACCOUNT_CONNECTION_REQUIRED")
                return await accounts.get_usable_token(s, row, client)

            try:
                token = await db.transaction(refresh)
            except Exception:

                async def invalidate(s):
                    await s.execute(
                        update(Account)
                        .where(
                            Account.account_id == account_id, Account.status == "linked"
                        )
                        .values(
                            status="needs_reauth", last_error="TOKEN_REFRESH_FAILED"
                        )
                    )

                await db.transaction(invalidate)
                raise SocialError("ACCOUNT_NEEDS_REAUTH", reauth=True) from None

            async def publish(s):
                await accounts.lock_user(s, user_id, provider)
                initial = await s.get(Post, post_id)
                _, _, url = await target(s, user_id, initial.place_id)
                row = (
                    await s.execute(
                        select(Post)
                        .where(Post.post_id == post_id)
                        .with_for_update()
                        .execution_options(populate_existing=True)
                    )
                ).scalar_one()
                if row.status != "POSTING":
                    return {"skipped": True}
                account = await s.get(Account, account_id)
                if not account or account.status != "linked" or account.deleted:
                    raise SocialError("ACCOUNT_CONNECTION_REQUIRED")
                # 마지막까지 사이트 잠금을 유지한다: 게시 도중 사이트를 내리는 경합을 직렬화한다.
                if url != row.link_url:
                    raise SocialError("PUBLISH_URL_CHANGED")
                if (
                    weighted_length(row.body, provider)
                    > adapter(provider).weighted_limit()
                ):
                    raise SocialError("TEXT_TOO_LONG")
                identity = await adapter(provider).me(token, client=client)
                if str(identity["id"]) != account.provider_user_id:
                    raise SocialError("ACCOUNT_IDENTITY_CHANGED", reauth=True)
                result = await adapter(provider).publish(row.body, token, client=client)
                row.status, row.provider_post_id, row.permalink = (
                    "POSTED",
                    result["id"],
                    result["permalink"],
                )
                row.posted_at = row.updated_at = datetime.now(timezone.utc)
                row.last_error = None
                await s.execute(
                    update(places)
                    .where(places.place_id == row.place_id)
                    .values(content_updated_at=row.posted_at)
                )
                # 재빌드는 사이트당 큐 키를 쓰되 여기서 외부 게시를 다시 호출하지 않는다.
                await s.execute(
                    text("""INSERT INTO jobs(job_type,payload,dedupe_key) VALUES
                    (4,CAST(:payload AS jsonb),:key) ON CONFLICT (dedupe_key)
                    WHERE status IN (1,2) AND dedupe_key IS NOT NULL DO NOTHING"""),
                    {
                        "payload": json.dumps(
                            {
                                "place_id": str(row.place_id),
                                "owner_user_id": str(user_id),
                                "publish": True,
                            }
                        ),
                        "key": f"social-build:{post_id}",
                    },
                )
                await s.execute(text("SELECT pg_notify('web4ai_job', '')"))
                return {"post_id": str(post_id), "permalink": result["permalink"]}

            # API 성공 뒤 DB 저장 실패도 결과 불명이다: FAILED로 떨어뜨려 재게시시키지 않는다.
            return await db.transaction(publish)
        except SocialOutcomeUnknown:
            await set_failure(post_id, "POST_RESULT_UNKNOWN", status="UNKNOWN")
            raise SocialOutcomeUnknown("POST_RESULT_UNKNOWN") from None
        except (SocialError, HTTPException) as ex:
            if getattr(ex, "reauth", False):

                async def reauth(s):
                    await s.execute(
                        update(Account)
                        .where(
                            Account.account_id == account_id, Account.status == "linked"
                        )
                        .values(
                            status="needs_reauth", last_error="ACCOUNT_NEEDS_REAUTH"
                        )
                    )

                await db.transaction(reauth)
            await set_failure(
                post_id,
                str(ex)
                if isinstance(ex, SocialError)
                else "PUBLISH_TARGET_UNAVAILABLE",
            )
            raise SocialError("POST_FAILED") from None
        except Exception:
            await set_failure(post_id, "POST_RESULT_UNKNOWN", status="UNKNOWN")
            raise SocialOutcomeUnknown("POST_RESULT_UNKNOWN") from None