"""群聊人设卡 —— 数据层：仓储

只做存储读写，不关心数据来源（群事件、历史导入走同一个入口）。
业务层与数据来源层都只通过这里的函数访问数据库。
"""

from datetime import datetime
from typing import Optional

from nonebot import require

require("nonebot_plugin_orm")

from nonebot_plugin_orm import get_session
from sqlalchemy import delete, func, select

from .models import (
    PersonaChatLog,
    PersonaGroup,
    PersonaImage,
    PersonaImpression,
    PersonaSummary,
    PersonaUser,
)

# 单用户单群语料滚动保留上限（超出淘汰最旧，DESIGN.md §6）
ROLLING_WINDOW = 3000

# 发言段链条：同一说话人两条消息间隔不超过该秒数，视为同一段发言
FOLLOWS_MAX_GAP = 300  # 5 分钟


# ---------- 管理群列表（数据来源总闸门） ----------

async def ensure_schema() -> None:
    """schema 管理（幂等）：补列 + 建新表。

    orm 自动同步已被禁用（见 __init__.py），且 orm 的启动建表早于本插件
    模型导入（新表不会自动建），因此建表/补列都走这里。
    """
    from sqlalchemy import text
    from sqlalchemy.exc import OperationalError

    statements = [
        "ALTER TABLE persona_group ADD COLUMN group_name VARCHAR(64) DEFAULT ''",
        "ALTER TABLE persona_chat_log ADD COLUMN follows_id INTEGER",
        "ALTER TABLE persona_chat_log ADD COLUMN target_inherited BOOLEAN DEFAULT 0",
        "ALTER TABLE persona_chat_log ADD COLUMN image_count INTEGER DEFAULT 0",
        "ALTER TABLE persona_chat_log ADD COLUMN image_hashes TEXT",
    ]
    async with get_session() as session:
        for stmt in statements:
            try:
                await session.execute(text(stmt))
                await session.commit()
            except OperationalError:
                pass  # 列已存在
        # 幂等创建缺失的表（本插件全部模型共用同一 metadata）
        def _create_tables(sync_session) -> None:
            PersonaImage.metadata.create_all(sync_session.connection())

        await session.run_sync(_create_tables)


async def list_groups() -> list[PersonaGroup]:
    """全部被管理的群（数据库直读，不依赖 OneBot）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaGroup).order_by(PersonaGroup.group_id)
        )
        return list(result.scalars().all())


async def add_group(group_id: int, group_name: str = "") -> None:
    """加入管理列表（幂等：已存在则更新名称），默认不采集"""
    async with get_session() as session:
        row = await session.get(PersonaGroup, group_id)
        if row is None:
            session.add(PersonaGroup(group_id=group_id, group_name=group_name))
        elif group_name and row.group_name != group_name:
            row.group_name = group_name
        await session.commit()


async def remove_group(group_id: int) -> None:
    """移出管理列表（数据保留，重新加入可续上）"""
    async with get_session() as session:
        await session.execute(
            delete(PersonaGroup).where(PersonaGroup.group_id == group_id)
        )
        await session.commit()


async def backfill_group_names(names: dict[int, str]) -> None:
    """用 OneBot 群列表回填已管理群的名称（仅在拉取群列表时顺带做）"""
    async with get_session() as session:
        rows = (await session.execute(select(PersonaGroup))).scalars().all()
        changed = False
        for row in rows:
            name = names.get(row.group_id, "")
            if name and row.group_name != name:
                row.group_name = name
                changed = True
        if changed:
            await session.commit()


async def set_group_enabled(group_id: int, enabled: bool) -> None:
    """开/关某群的采集（幂等：不存在则创建，存在则更新）"""
    async with get_session() as session:
        row = await session.get(PersonaGroup, group_id)
        if row is None:
            session.add(PersonaGroup(group_id=group_id, enabled=enabled))
        else:
            row.enabled = enabled
            row.updated_at = datetime.now()
        await session.commit()


async def is_group_enabled(group_id: int) -> bool:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaGroup).where(PersonaGroup.group_id == group_id)
        )
        row = result.scalar()
        return bool(row and row.enabled)


async def enabled_groups() -> list[int]:
    """全部开启采集的群（调度/采集层扫描用）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaGroup.group_id).where(PersonaGroup.enabled.is_(True))
        )
        return [row[0] for row in result.all()]


# ---------- 参与者 ----------

async def is_joined(user_id: int, group_id: int) -> bool:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaUser).where(
                PersonaUser.user_id == user_id, PersonaUser.group_id == group_id
            )
        )
        return result.scalar() is not None


async def join(user_id: int, group_id: int) -> None:
    async with get_session() as session:
        session.add(PersonaUser(user_id=user_id, group_id=group_id))
        await session.commit()


async def leave(user_id: int, group_id: int) -> None:
    async with get_session() as session:
        await session.execute(
            delete(PersonaUser).where(
                PersonaUser.user_id == user_id, PersonaUser.group_id == group_id
            )
        )
        await session.commit()


async def joined_users(group_id: int) -> list[int]:
    """某群全部参与者（调度层扫描用）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaUser.user_id).where(PersonaUser.group_id == group_id)
        )
        return [row[0] for row in result.all()]


# ---------- 语料 ----------

async def add_chat_log(
    user_id: int,
    group_id: int,
    content: str,
    nickname: str = "",
    target_user_id: Optional[int] = None,
    reply_to_content: Optional[str] = None,
    image_count: int = 0,
    image_hashes: Optional[str] = None,
) -> int:
    """落库一条语料，返回新语料 id

    发言段链条：同一说话人的上一条语料记为 follows_id（间隔 ≤ FOLLOWS_MAX_GAP）；
    本条无显式目标（回复/@）时从链条继承 target_user_id——对上面那句的解释/补充
    仍视为发给同一对象，不丢语境。
    """
    async with get_session() as session:
        prev = (
            await session.execute(
                select(PersonaChatLog)
                .where(
                    PersonaChatLog.user_id == user_id,
                    PersonaChatLog.group_id == group_id,
                )
                .order_by(PersonaChatLog.id.desc())
                .limit(1)
            )
        ).scalar()
        follows_id = None
        inherited = False
        if prev is not None and (
            datetime.now() - prev.created_at
        ).total_seconds() <= FOLLOWS_MAX_GAP:
            follows_id = prev.id
            if target_user_id is None:
                target_user_id = prev.target_user_id
                inherited = target_user_id is not None
        log = PersonaChatLog(
            user_id=user_id,
            group_id=group_id,
            nickname=nickname,
            content=content,
            target_user_id=target_user_id,
            target_inherited=inherited,
            follows_id=follows_id,
            image_count=image_count,
            image_hashes=image_hashes,
            reply_to_content=reply_to_content,
        )
        session.add(log)
        await session.commit()
        await session.refresh(log)
    return log.id


async def count_chat_log(user_id: int, group_id: int) -> int:
    async with get_session() as session:
        result = await session.execute(
            select(func.count(PersonaChatLog.id)).where(
                PersonaChatLog.user_id == user_id, PersonaChatLog.group_id == group_id
            )
        )
        return result.scalar_one()


async def latest_chat_logs(
    user_id: int, group_id: int, limit: int, before_id: Optional[int] = None
) -> list[PersonaChatLog]:
    """按 id 倒序取最新 limit 条；before_id 用于翻页"""
    stmt = (
        select(PersonaChatLog)
        .where(PersonaChatLog.user_id == user_id, PersonaChatLog.group_id == group_id)
        .order_by(PersonaChatLog.id.desc())
        .limit(limit)
    )
    if before_id is not None:
        stmt = stmt.where(PersonaChatLog.id <= before_id)
    async with get_session() as session:
        result = await session.execute(stmt)
        return list(result.scalars().all())


async def chat_logs_since(
    user_id: int, group_id: int, since_id: int, limit: int
) -> list[PersonaChatLog]:
    """按 id 正序取 id > since_id 的语料（增量印象生成的输入）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaChatLog)
            .where(
                PersonaChatLog.user_id == user_id,
                PersonaChatLog.group_id == group_id,
                PersonaChatLog.id > since_id,
            )
            .order_by(PersonaChatLog.id.asc())
            .limit(limit)
        )
        return list(result.scalars().all())


async def prune_chat_log(user_id: int, group_id: int, keep: int = ROLLING_WINDOW) -> int:
    """淘汰滚动窗口外的旧语料，返回删除条数"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaChatLog.id)
            .where(
                PersonaChatLog.user_id == user_id, PersonaChatLog.group_id == group_id
            )
            .order_by(PersonaChatLog.id.desc())
            .offset(keep)
        )
        stale_ids = [row[0] for row in result.all()]
        if stale_ids:
            await session.execute(
                delete(PersonaChatLog).where(PersonaChatLog.id.in_(stale_ids))
            )
            await session.commit()
        return len(stale_ids)


# ---- 统计与分页（Web 管理后台用） ----

async def count_chat_log_group(group_id: int) -> int:
    async with get_session() as session:
        result = await session.execute(
            select(func.count(PersonaChatLog.id)).where(
                PersonaChatLog.group_id == group_id
            )
        )
        return result.scalar_one()


async def count_impressions_group(group_id: int) -> int:
    async with get_session() as session:
        result = await session.execute(
            select(func.count(PersonaImpression.id)).where(
                PersonaImpression.group_id == group_id
            )
        )
        return result.scalar_one()


async def count_summaries_group(group_id: int) -> int:
    async with get_session() as session:
        result = await session.execute(
            select(func.count(PersonaSummary.id)).where(
                PersonaSummary.group_id == group_id
            )
        )
        return result.scalar_one()


async def corpus_counts_by_group() -> dict[int, int]:
    """各群语料条数（一次聚合查询，替代逐群 count）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaChatLog.group_id, func.count(PersonaChatLog.id)).group_by(
                PersonaChatLog.group_id
            )
        )
        return {int(row[0]): int(row[1]) for row in result.all()}


async def impression_counts_by_group() -> dict[int, int]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaImpression.group_id, func.count(PersonaImpression.id)).group_by(
                PersonaImpression.group_id
            )
        )
        return {int(row[0]): int(row[1]) for row in result.all()}


async def summary_counts_by_group() -> dict[int, int]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaSummary.group_id, func.count(PersonaSummary.id)).group_by(
                PersonaSummary.group_id
            )
        )
        return {int(row[0]): int(row[1]) for row in result.all()}


async def participant_counts_by_group() -> dict[int, int]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaUser.group_id, func.count(PersonaUser.user_id)).group_by(
                PersonaUser.group_id
            )
        )
        return {int(row[0]): int(row[1]) for row in result.all()}


async def chat_log_stats_by_user(group_id: int) -> list[tuple[int, int]]:
    """群内每人语料条数（(user_id, count)，按条数倒序）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaChatLog.user_id, func.count(PersonaChatLog.id))
            .where(PersonaChatLog.group_id == group_id)
            .group_by(PersonaChatLog.user_id)
            .order_by(func.count(PersonaChatLog.id).desc())
        )
        return [(int(row[0]), int(row[1])) for row in result.all()]


async def list_logs(
    group_id: int,
    user_id: Optional[int] = None,
    offset: int = 0,
    limit: int = 50,
) -> list[PersonaChatLog]:
    """语料分页（倒序，新在前）"""
    stmt = select(PersonaChatLog).where(PersonaChatLog.group_id == group_id)
    if user_id is not None:
        stmt = stmt.where(PersonaChatLog.user_id == user_id)
    stmt = stmt.order_by(PersonaChatLog.id.desc()).offset(offset).limit(limit)
    async with get_session() as session:
        result = await session.execute(stmt)
        return list(result.scalars().all())


async def count_logs_filtered(group_id: int, user_id: Optional[int] = None) -> int:
    stmt = select(func.count(PersonaChatLog.id)).where(
        PersonaChatLog.group_id == group_id
    )
    if user_id is not None:
        stmt = stmt.where(PersonaChatLog.user_id == user_id)
    async with get_session() as session:
        result = await session.execute(stmt)
        return result.scalar_one()


async def list_impressions_group(
    group_id: int, offset: int = 0, limit: int = 50
) -> list[PersonaImpression]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaImpression)
            .where(PersonaImpression.group_id == group_id)
            .order_by(PersonaImpression.id.desc())
            .offset(offset)
            .limit(limit)
        )
        return list(result.scalars().all())


async def list_summaries_group(group_id: int) -> list[PersonaSummary]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaSummary)
            .where(PersonaSummary.group_id == group_id)
            .order_by(PersonaSummary.version.desc())
        )
        return list(result.scalars().all())


async def delete_logs(group_id: int, user_id: Optional[int] = None) -> int:
    """删除语料（可只删某人），返回删除条数"""
    stmt = delete(PersonaChatLog).where(PersonaChatLog.group_id == group_id)
    if user_id is not None:
        stmt = stmt.where(PersonaChatLog.user_id == user_id)
    async with get_session() as session:
        result = await session.execute(stmt)
        await session.commit()
        return result.rowcount or 0


async def clear_group_data(group_id: int) -> None:
    """清空某群全部数据：语料 + 印象 + 画像 + 参与者（群开关行保留）"""
    async with get_session() as session:
        await session.execute(delete(PersonaChatLog).where(PersonaChatLog.group_id == group_id))
        await session.execute(delete(PersonaImpression).where(PersonaImpression.group_id == group_id))
        await session.execute(delete(PersonaSummary).where(PersonaSummary.group_id == group_id))
        await session.execute(delete(PersonaUser).where(PersonaUser.group_id == group_id))
        await session.commit()


# ---------- 印象 ----------

async def add_impression(
    user_id: int,
    group_id: int,
    content: str,
    cover_from_id: int,
    cover_to_id: int,
    model: str = "",
) -> None:
    async with get_session() as session:
        session.add(
            PersonaImpression(
                user_id=user_id,
                group_id=group_id,
                content=content,
                cover_from_id=cover_from_id,
                cover_to_id=cover_to_id,
                model=model,
            )
        )
        await session.commit()


async def latest_impression(user_id: int, group_id: int) -> Optional[PersonaImpression]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaImpression)
            .where(
                PersonaImpression.user_id == user_id,
                PersonaImpression.group_id == group_id,
            )
            .order_by(PersonaImpression.id.desc())
            .limit(1)
        )
        return result.scalar()


async def count_impressions(user_id: int, group_id: int) -> int:
    async with get_session() as session:
        result = await session.execute(
            select(func.count(PersonaImpression.id)).where(
                PersonaImpression.user_id == user_id,
                PersonaImpression.group_id == group_id,
            )
        )
        return result.scalar_one()


async def list_impressions(
    user_id: int, group_id: int, limit: int
) -> list[PersonaImpression]:
    """按 id 正序取最近 limit 条印象（画像生成的输入，最旧在前）"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaImpression)
            .where(
                PersonaImpression.user_id == user_id,
                PersonaImpression.group_id == group_id,
            )
            .order_by(PersonaImpression.id.desc())
            .limit(limit)
        )
        return list(reversed(result.scalars().all()))


# ---------- 画像 ----------

async def latest_summary(user_id: int, group_id: int) -> Optional[PersonaSummary]:
    async with get_session() as session:
        result = await session.execute(
            select(PersonaSummary)
            .where(
                PersonaSummary.user_id == user_id,
                PersonaSummary.group_id == group_id,
            )
            .order_by(PersonaSummary.version.desc())
            .limit(1)
        )
        return result.scalar()


async def add_summary(
    user_id: int,
    group_id: int,
    card_text: str,
    corpus_count: int = 0,
    impression_count: int = 0,
    model: str = "",
) -> int:
    """新增画像版本，version 自动 +1，返回新版本号。

    注意：并发调用可能撞 UNIQUE(user_id, group_id, version)，由调度层加锁保护。
    """
    prev = await latest_summary(user_id, group_id)
    version = (prev.version + 1) if prev else 1
    async with get_session() as session:
        session.add(
            PersonaSummary(
                user_id=user_id,
                group_id=group_id,
                version=version,
                card_text=card_text,
                corpus_count=corpus_count,
                impression_count=impression_count,
                model=model,
            )
        )
        await session.commit()
    return version


async def list_summaries(user_id: int, group_id: int) -> list[PersonaSummary]:
    """全部历史版本（版本对比用），旧版在前"""
    async with get_session() as session:
        result = await session.execute(
            select(PersonaSummary)
            .where(
                PersonaSummary.user_id == user_id,
                PersonaSummary.group_id == group_id,
            )
            .order_by(PersonaSummary.version.asc())
        )
        return list(result.scalars().all())