"""OA 发起审批草稿 CRUD（oa_instance_draft）"""
from __future__ import annotations

import json
from datetime import datetime
from typing import Any, Dict, List, Optional, Tuple

from sqlalchemy import func, or_
from sqlalchemy.orm import Session

from app.core.utils import generate_uuid
from app.crud import oa_approval as oa_crud
from app.models.models import OaApp, OaAppGroup, OaAppVersion, OaInstanceDraft
from app.services.oa_related_approval import flatten_form_fields_for_summary


def _loads(raw: Any, default: Any) -> Any:
    if raw is None or raw == "":
        return default
    if isinstance(raw, (dict, list)):
        return raw
    try:
        return json.loads(raw)
    except (TypeError, ValueError, json.JSONDecodeError):
        return default


def _dumps(obj: Any) -> Optional[str]:
    if obj is None:
        return None
    return json.dumps(obj, ensure_ascii=False)


def row_to_dict(
    d: OaInstanceDraft,
    *,
    app_name: str = "",
    version_no: Optional[int] = None,
    group_id: str = "",
    group_name: str = "",
    include_payload: bool = False,
) -> Dict[str, Any]:
    out: Dict[str, Any] = {
        "id": d.id,
        "appId": d.app_id,
        "appVersionId": d.app_version_id,
        "appName": app_name or "",
        "versionNo": version_no,
        "groupId": group_id or "",
        "groupName": group_name or "",
        "title": d.title or "",
        "ownerUserId": d.owner_user_id,
        "initiatorDeptId": d.initiator_dept_id or "",
        "status": "draft",
        "createTime": d.create_time.strftime("%Y-%m-%d %H:%M:%S") if d.create_time else "",
        "updateTime": d.update_time.strftime("%Y-%m-%d %H:%M:%S") if d.update_time else "",
    }
    if include_payload:
        out["formData"] = _loads(d.form_data_json, {}) or {}
        out["initiatorSelectByNode"] = _loads(d.initiator_select_json, {}) or {}
    return out


class DraftAccessError(ValueError):
    """草稿不存在或无权访问"""


def get_owned_draft(
    db: Session,
    draft_id: str,
    *,
    tenant_no: str,
    owner_user_id: str,
) -> OaInstanceDraft:
    row = (
        db.query(OaInstanceDraft)
        .filter(
            OaInstanceDraft.id == draft_id,
            OaInstanceDraft.tenant_no == tenant_no,
            OaInstanceDraft.owner_user_id == owner_user_id,
            OaInstanceDraft.del_flag == 0,
        )
        .first()
    )
    if not row:
        raise DraftAccessError("草稿不存在或无权访问")
    return row


def _enrich(db: Session, d: OaInstanceDraft, *, include_payload: bool = False) -> Dict[str, Any]:
    app = (
        db.query(OaApp)
        .filter(OaApp.id == d.app_id, OaApp.tenant_no == d.tenant_no, OaApp.del_flag == 0)
        .first()
    )
    ver = (
        db.query(OaAppVersion)
        .filter(OaAppVersion.id == d.app_version_id, OaAppVersion.del_flag == 0)
        .first()
    )
    group_name = ""
    group_id = ""
    if app and app.group_id:
        group_id = app.group_id
        g = (
            db.query(OaAppGroup)
            .filter(OaAppGroup.id == app.group_id, OaAppGroup.del_flag == 0)
            .first()
        )
        if g:
            group_name = g.group_name or ""
    return row_to_dict(
        d,
        app_name=(app.app_name if app else "") or "",
        version_no=ver.version_no if ver else None,
        group_id=group_id,
        group_name=group_name,
        include_payload=include_payload,
    )


def count_drafts(db: Session, *, tenant_no: str, owner_user_id: str) -> int:
    return (
        db.query(OaInstanceDraft)
        .filter(
            OaInstanceDraft.tenant_no == tenant_no,
            OaInstanceDraft.owner_user_id == owner_user_id,
            OaInstanceDraft.del_flag == 0,
        )
        .count()
    )


def list_drafts(
    db: Session,
    *,
    tenant_no: str,
    owner_user_id: str,
    keyword: Optional[str] = None,
    group_id: Optional[str] = None,
    update_time_from: Optional[datetime] = None,
    update_time_to: Optional[datetime] = None,
    page: int = 1,
    page_size: int = 20,
) -> Tuple[List[Dict[str, Any]], int]:
    q = (
        db.query(OaInstanceDraft, OaApp, OaAppVersion, OaAppGroup)
        .outerjoin(
            OaApp,
            (OaApp.id == OaInstanceDraft.app_id)
            & (OaApp.tenant_no == OaInstanceDraft.tenant_no)
            & (OaApp.del_flag == 0),
        )
        .outerjoin(
            OaAppVersion,
            (OaAppVersion.id == OaInstanceDraft.app_version_id) & (OaAppVersion.del_flag == 0),
        )
        .outerjoin(
            OaAppGroup,
            (OaAppGroup.id == OaApp.group_id) & (OaAppGroup.del_flag == 0),
        )
        .filter(
            OaInstanceDraft.tenant_no == tenant_no,
            OaInstanceDraft.owner_user_id == owner_user_id,
            OaInstanceDraft.del_flag == 0,
        )
    )
    kw = (keyword or "").strip()
    if kw:
        like = f"%{kw}%"
        q = q.filter(or_(OaApp.app_name.like(like), OaInstanceDraft.title.like(like)))
    gid = (group_id or "").strip()
    if gid:
        q = q.filter(OaApp.group_id == gid)
    if update_time_from is not None:
        q = q.filter(OaInstanceDraft.update_time >= update_time_from)
    if update_time_to is not None:
        q = q.filter(OaInstanceDraft.update_time <= update_time_to)

    total = q.order_by(None).with_entities(func.count(OaInstanceDraft.id)).scalar() or 0
    page = max(1, page)
    page_size = min(max(1, page_size), 100)
    rows = (
        q.order_by(OaInstanceDraft.update_time.desc())
        .offset((page - 1) * page_size)
        .limit(page_size)
        .all()
    )
    items: List[Dict[str, Any]] = []
    for d, app, ver, group in rows:
        item = row_to_dict(
            d,
            app_name=(app.app_name if app else "") or "",
            version_no=ver.version_no if ver else None,
            group_id=(app.group_id if app else "") or "",
            group_name=(group.group_name if group else "") or "",
        )
        schema = _loads(getattr(ver, "form_schema_json", None), {}) if ver else {}
        form_data = _loads(d.form_data_json, {}) or {}
        preview = [
            {"label": f.get("label") or "", "value": f.get("value") or ""}
            for f in flatten_form_fields_for_summary(schema, form_data)[:3]
        ]
        item["previewFields"] = preview
        items.append(item)
    return items, int(total)


def get_draft_detail(
    db: Session,
    draft_id: str,
    *,
    tenant_no: str,
    owner_user_id: str,
) -> Dict[str, Any]:
    d = get_owned_draft(db, draft_id, tenant_no=tenant_no, owner_user_id=owner_user_id)
    return _enrich(db, d, include_payload=True)


def create_draft(
    db: Session,
    *,
    tenant_no: str,
    owner_user_id: str,
    app_id: str,
    form_data: Optional[Dict[str, Any]] = None,
    initiator_select_by_node: Optional[Dict[str, Any]] = None,
    initiator_dept_id: Optional[str] = None,
    title: Optional[str] = None,
    create_dept_id: str = "",
) -> Dict[str, Any]:
    app = oa_crud.get_app(db, app_id, tenant_no)
    if not app or app.status != "1":
        raise ValueError("应用不存在或已停用")
    ver = oa_crud._find_latest_published(db, app_id, tenant_no)
    if not ver:
        raise ValueError("应用尚未发布，无法暂存草稿")
    now = datetime.now()
    row = OaInstanceDraft(
        id=generate_uuid(),
        app_id=app_id,
        app_version_id=ver.id,
        title=(title or app.app_name or "")[:200] or None,
        form_data_json=_dumps(form_data or {}),
        initiator_select_json=_dumps(initiator_select_by_node or {}),
        initiator_dept_id=(initiator_dept_id or "").strip() or None,
        owner_user_id=owner_user_id,
        tenant_no=tenant_no,
        create_by=owner_user_id,
        create_dept_id=create_dept_id or "",
        create_time=now,
        update_by=owner_user_id,
        update_time=now,
        del_flag=0,
    )
    db.add(row)
    db.commit()
    db.refresh(row)
    return _enrich(db, row, include_payload=True)


def update_draft(
    db: Session,
    draft_id: str,
    *,
    tenant_no: str,
    owner_user_id: str,
    form_data: Optional[Dict[str, Any]] = None,
    initiator_select_by_node: Optional[Dict[str, Any]] = None,
    initiator_dept_id: Optional[str] = None,
    title: Optional[str] = None,
) -> Dict[str, Any]:
    d = get_owned_draft(db, draft_id, tenant_no=tenant_no, owner_user_id=owner_user_id)
    ver = oa_crud._find_latest_published(db, d.app_id, tenant_no)
    if ver:
        d.app_version_id = ver.id
    if form_data is not None:
        d.form_data_json = _dumps(form_data)
    if initiator_select_by_node is not None:
        d.initiator_select_json = _dumps(initiator_select_by_node)
    if initiator_dept_id is not None:
        d.initiator_dept_id = (initiator_dept_id or "").strip() or None
    if title is not None:
        d.title = (title or "")[:200] or None
    d.update_by = owner_user_id
    d.update_time = datetime.now()
    db.commit()
    db.refresh(d)
    return _enrich(db, d, include_payload=True)


def soft_delete_draft(
    db: Session,
    draft_id: str,
    *,
    tenant_no: str,
    owner_user_id: str,
) -> None:
    d = get_owned_draft(db, draft_id, tenant_no=tenant_no, owner_user_id=owner_user_id)
    d.del_flag = 1
    d.update_by = owner_user_id
    d.update_time = datetime.now()
    db.commit()


def batch_soft_delete_drafts(
    db: Session,
    ids: List[str],
    *,
    tenant_no: str,
    owner_user_id: str,
) -> int:
    cleaned = [str(x).strip() for x in (ids or []) if str(x).strip()]
    if not cleaned:
        raise ValueError("请选择要删除的草稿")
    rows = (
        db.query(OaInstanceDraft)
        .filter(
            OaInstanceDraft.id.in_(cleaned),
            OaInstanceDraft.tenant_no == tenant_no,
            OaInstanceDraft.owner_user_id == owner_user_id,
            OaInstanceDraft.del_flag == 0,
        )
        .all()
    )
    if len(rows) != len(set(cleaned)):
        raise DraftAccessError("草稿不存在或无权访问")
    now = datetime.now()
    for d in rows:
        d.del_flag = 1
        d.update_by = owner_user_id
        d.update_time = now
    db.commit()
    return len(rows)


def submit_draft(
    db: Session,
    draft_id: str,
    *,
    tenant_no: str,
    owner_user_id: str,
    form_data: Optional[Dict[str, Any]] = None,
    initiator_select_by_node: Optional[Dict[str, Any]] = None,
    initiator_dept_id: Optional[str] = None,
    title: Optional[str] = None,
) -> Dict[str, Any]:
    """提交草稿：走 start_instance，成功后软删草稿。"""
    from app.services.oa_engine import start_instance

    d = get_owned_draft(db, draft_id, tenant_no=tenant_no, owner_user_id=owner_user_id)
    payload_form = form_data if form_data is not None else (_loads(d.form_data_json, {}) or {})
    payload_select = (
        initiator_select_by_node
        if initiator_select_by_node is not None
        else (_loads(d.initiator_select_json, {}) or {})
    )
    dept = initiator_dept_id if initiator_dept_id is not None else d.initiator_dept_id
    use_title = title if title is not None else d.title

    data = start_instance(
        db,
        tenant_no=tenant_no,
        app_id=d.app_id,
        initiator_user_id=owner_user_id,
        initiator_dept_id=dept,
        form_data=payload_form if isinstance(payload_form, dict) else {},
        title=use_title,
        initiator_select_by_node=payload_select if isinstance(payload_select, dict) else {},
    )
    d.del_flag = 1
    d.update_by = owner_user_id
    d.update_time = datetime.now()
    db.commit()
    return data