"""Light-app registry API (轻应用中心 / 应用管理).

Registered mini-applications, **global / shared** (no user scoping). Two kinds:

- ``window_open`` — launched in a new browser tab from the 应用列表 card grid.
- ``iframe`` — embedded under a parent sidebar menu (``mount_location``) and
  injected into the sidebar as a child item.

Both kinds carry ``route_params`` — a list of descriptors the frontend resolves
at launch time (login params read from ``localStorage.userInfo``; theme params
use a literal value) and appends to ``url`` as query string.

Reads are open to any authenticated user; writes require admin.

Routes (prefix ``/api/light-apps``):
    GET    ""           list apps (filters: app_type / mount_location / enabled_only / search)
    POST   ""           create app (admin)
    GET    "/{app_id}"  read one
    PUT    "/{app_id}"  update one (admin)
    DELETE "/{app_id}"  delete one (admin)
"""

from __future__ import annotations

from datetime import datetime

from fastapi import APIRouter, HTTPException, Query, Request
from pydantic import BaseModel, Field

from app.gateway.deps import get_current_user, get_optional_user_from_request
from deerflow.persistence.light_apps import DuplicateLightAppNameError, LightAppStore

router = APIRouter(prefix="/api/light-apps", tags=["light-apps"])

_VALID_TYPES = {"window_open", "iframe"}


# ── schemas ──────────────────────────────────────────────────────────────


class RouteParam(BaseModel):
    key: str = Field(..., min_length=1, max_length=128)
    paramType: str = Field(..., pattern="^(login|theme)$")
    # login: which userInfo field, or "other"
    source: str | None = Field(default=None, max_length=64)
    # login + source == "other": literal value
    customValue: str | None = Field(default=None, max_length=2048)
    # theme: the theme value (e.g. dark-blue / red / blue), editable
    themeValue: str | None = Field(default=None, max_length=128)


class LightAppResponse(BaseModel):
    app_id: str
    name: str
    description: str | None = None
    app_type: str
    url: str
    route_params: list[RouteParam] = Field(default_factory=list)
    mount_location: str | None = None
    icon: str | None = None
    enabled: bool = True
    sort_order: int = 0
    created_by: str | None = None
    updated_by: str | None = None
    created_at: datetime | str | None = None
    updated_at: datetime | str | None = None


class LightAppListResponse(BaseModel):
    apps: list[LightAppResponse]


class LightAppCreateRequest(BaseModel):
    name: str = Field(..., min_length=1, max_length=127)
    description: str | None = Field(default=None, max_length=1000)
    app_type: str = Field(..., pattern="^(window_open|iframe)$")
    url: str = Field(..., min_length=1)
    route_params: list[RouteParam] = Field(default_factory=list)
    mount_location: str | None = Field(default=None, max_length=64)
    icon: str | None = Field(default=None, max_length=64)
    enabled: bool = True
    sort_order: int = 0


class LightAppUpdateRequest(BaseModel):
    name: str | None = Field(default=None, min_length=1, max_length=127)
    description: str | None = Field(default=None, max_length=1000)
    app_type: str | None = Field(default=None, pattern="^(window_open|iframe)$")
    url: str | None = Field(default=None, min_length=1)
    route_params: list[RouteParam] | None = None
    mount_location: str | None = Field(default=None, max_length=64)
    icon: str | None = Field(default=None, max_length=64)
    enabled: bool | None = None
    sort_order: int | None = None


# ── helpers ──────────────────────────────────────────────────────────────


def _get_store(request: Request) -> LightAppStore:
    store = getattr(request.app.state, "light_app_store", None)
    if store is None:
        raise HTTPException(status_code=503, detail="Light app store not available")
    return store


async def _require_admin(request: Request) -> None:
    """Reject non-admins. Lets the call through when auth is disabled."""
    user = await get_optional_user_from_request(request)
    if user is None:
        return
    if getattr(user, "system_role", None) != "admin":
        raise HTTPException(status_code=403, detail="轻应用管理仅限管理员")


def _validate_payload(app_type: str | None, mount_location: str | None) -> None:
    if app_type == "iframe" and not mount_location:
        raise HTTPException(status_code=400, detail="iframe 类型必须选择挂载菜单")


def _dump_params(params) -> list[dict]:
    return [p.model_dump() if isinstance(p, RouteParam) else dict(p) for p in (params or [])]


# ── routes ───────────────────────────────────────────────────────────────


@router.get("", response_model=LightAppListResponse)
async def list_light_apps(
    request: Request,
    app_type: str | None = Query(default=None),
    mount_location: str | None = Query(default=None),
    enabled_only: bool = Query(default=False),
    search: str | None = Query(default=None),
) -> LightAppListResponse:
    store = _get_store(request)
    rows = await store.list_apps(app_type=app_type, mount_location=mount_location, enabled_only=enabled_only)
    if search:
        needle = search.strip().lower()
        rows = [r for r in rows if needle in str(r.get("name", "")).lower() or needle in str(r.get("description") or "").lower()]
    return LightAppListResponse(apps=[LightAppResponse(**r) for r in rows])


@router.post("", response_model=LightAppResponse)
async def create_light_app(request: Request, body: LightAppCreateRequest) -> LightAppResponse:
    await _require_admin(request)
    _validate_payload(body.app_type, body.mount_location)
    store = _get_store(request)
    user_id = await get_current_user(request)
    try:
        row = await store.create_app(
            {
                "name": body.name,
                "description": body.description,
                "app_type": body.app_type,
                "url": body.url,
                "route_params": _dump_params(body.route_params),
                "mount_location": body.mount_location if body.app_type == "iframe" else None,
                "icon": body.icon,
                "enabled": body.enabled,
                "sort_order": body.sort_order,
                "created_by": user_id,
            }
        )
    except DuplicateLightAppNameError:
        raise HTTPException(status_code=409, detail="应用名称已存在")
    return LightAppResponse(**row)


@router.get("/{app_id}", response_model=LightAppResponse)
async def get_light_app(request: Request, app_id: str) -> LightAppResponse:
    store = _get_store(request)
    row = await store.get_app(app_id)
    if row is None:
        raise HTTPException(status_code=404, detail="应用不存在")
    return LightAppResponse(**row)


@router.put("/{app_id}", response_model=LightAppResponse)
async def update_light_app(request: Request, app_id: str, body: LightAppUpdateRequest) -> LightAppResponse:
    await _require_admin(request)
    store = _get_store(request)
    user_id = await get_current_user(request)

    fields = body.model_dump(exclude_unset=True)
    if "route_params" in fields:
        fields["route_params"] = _dump_params(body.route_params)

    # Resolve the effective type/mount to validate the iframe→mount invariant.
    existing = await store.get_app(app_id)
    if existing is None:
        raise HTTPException(status_code=404, detail="应用不存在")
    eff_type = fields.get("app_type", existing.get("app_type"))
    eff_mount = fields.get("mount_location", existing.get("mount_location"))
    _validate_payload(eff_type, eff_mount)
    if eff_type == "window_open":
        fields["mount_location"] = None

    fields["updated_by"] = user_id
    try:
        row = await store.update_app(app_id, fields)
    except DuplicateLightAppNameError:
        raise HTTPException(status_code=409, detail="应用名称已存在")
    if row is None:
        raise HTTPException(status_code=404, detail="应用不存在")
    return LightAppResponse(**row)


@router.delete("/{app_id}")
async def delete_light_app(request: Request, app_id: str) -> dict:
    await _require_admin(request)
    store = _get_store(request)
    deleted = await store.delete_app(app_id)
    if not deleted:
        raise HTTPException(status_code=404, detail="应用不存在")
    return {"success": True}