import io
import zipfile

import qrcode
from fastapi import APIRouter, Depends, Form, Request, status
from fastapi.responses import HTMLResponse, RedirectResponse, Response, StreamingResponse
from sqlalchemy import func, select
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.orm import selectinload

from app.database import get_db
from app.models import AdminUser, Protocol, VpnClient, VpnServer, XuiPanel, XuiPanelInbound, XuiSiteClient
from app.services import vpn as vpn_service
from app.services import xui_panels as xui_service

router = APIRouter(prefix="/admin", tags=["admin"])


async def require_admin(request: Request, db: AsyncSession = Depends(get_db)) -> AdminUser | RedirectResponse:
    admin_id = request.session.get("admin_id")
    if not admin_id:
        return RedirectResponse("/admin/login", status_code=status.HTTP_303_SEE_OTHER)
    user = await db.get(AdminUser, admin_id)
    if not user or not user.is_active:
        request.session.clear()
        return RedirectResponse("/admin/login", status_code=status.HTTP_303_SEE_OTHER)
    return user


def _is_redirect(value: object) -> bool:
    return isinstance(value, RedirectResponse)


@router.get("", response_class=HTMLResponse)
async def dashboard(request: Request, db: AsyncSession = Depends(get_db), admin=Depends(require_admin)):
    if _is_redirect(admin):
        return admin

    xui_panels = await xui_service.list_panels(db)
    xui_clients_total = await db.scalar(select(func.count()).select_from(XuiSiteClient)) or 0
    user_inbounds_total = await db.scalar(
        select(func.count())
        .select_from(XuiPanelInbound)
        .where(XuiPanelInbound.is_available_for_users.is_(True))
    ) or 0
    user_inbounds_by_panel: dict[int, list] = {}
    for panel in xui_panels:
        rows = await xui_service.list_user_inbounds(db, panel.id)
        user_inbounds_by_panel[panel.id] = [
            {"inbound_id": r.inbound_id, "protocol": r.protocol, "remark": r.remark, "port": r.port}
            for r in rows
        ]

    return request.app.state.templates.TemplateResponse(
        "admin/dashboard.html",
        {
            "request": request,
            "admin": admin,
            "xui_panels": xui_panels,
            "xui_clients_total": xui_clients_total,
            "user_inbounds_total": user_inbounds_total,
            "user_inbounds_by_panel": user_inbounds_by_panel,
            "app_name": request.app.state.settings.app_name,
        },
    )


@router.get("/servers", response_class=HTMLResponse)
async def servers_page(admin=Depends(require_admin)):
    """WG/AWG servers UI временно скрыт — редирект на клиентов 3x-ui."""
    if _is_redirect(admin):
        return admin
    return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/servers")
async def create_server(
    name: str = Form(""),
    protocol: str = Form(...),
    ssh_host: str = Form(...),
    ssh_port: int = Form(22),
    ssh_username: str = Form(...),
    ssh_password: str = Form(""),
    ssh_private_key: str = Form(""),
    public_host: str = Form(""),
    public_port: str = Form(""),
    dns: str = Form("1.1.1.1"),
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    try:
        port_value = int(public_port) if public_port.strip() else None
        await vpn_service.create_server(
            db,
            name=name,
            protocol=protocol,
            ssh_host=ssh_host,
            ssh_port=ssh_port,
            ssh_username=ssh_username,
            ssh_password=ssh_password,
            ssh_private_key=ssh_private_key,
            public_host=public_host or None,
            public_port=port_value,
            dns=dns,
        )
    except Exception as exc:  # noqa: BLE001
        return RedirectResponse(
            f"/admin/servers?flash=error:{exc}",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    return RedirectResponse("/admin/servers?flash=created", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/servers/{server_id}/sync")
async def sync_server(
    server_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    await vpn_service.sync_server_config(db, server_id)
    return RedirectResponse("/admin/servers", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/servers/{server_id}/check-ssh")
async def check_ssh(
    server_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    try:
        await vpn_service.check_server_ssh(db, server_id)
    except Exception as exc:  # noqa: BLE001
        return RedirectResponse(
            f"/admin/servers?flash=error:{exc}",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    return RedirectResponse("/admin/servers?flash=ssh_ok", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/servers/{server_id}/install-vpn")
async def install_vpn(
    server_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    try:
        await vpn_service.install_vpn_on_server(db, server_id)
        return RedirectResponse(
            "/admin/servers?flash=vpn_installed",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    except Exception as exc:  # noqa: BLE001
        return RedirectResponse(
            f"/admin/servers?flash=error:{exc}",
            status_code=status.HTTP_303_SEE_OTHER,
        )


@router.post("/servers/{server_id}/delete")
async def delete_server(
    server_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    server = await db.get(VpnServer, server_id)
    if server:
        await db.delete(server)
        await db.commit()
    return RedirectResponse("/admin/servers?flash=deleted", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/servers/{server_id}")
async def update_server(
    server_id: int,
    name: str = Form(""),
    public_host: str = Form(...),
    public_port: int = Form(...),
    dns: str = Form("1.1.1.1"),
    ssh_host: str = Form(""),
    ssh_port: int = Form(22),
    ssh_username: str = Form(""),
    ssh_password: str = Form(""),
    ssh_private_key: str = Form(""),
    clear_ssh_password: str = Form(""),
    clear_ssh_private_key: str = Form(""),
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    try:
        await vpn_service.update_server_settings(
            db,
            server_id,
            name=name or None,
            public_host=public_host,
            public_port=public_port,
            dns=dns,
            ssh_host=ssh_host,
            ssh_port=ssh_port,
            ssh_username=ssh_username,
            ssh_password=ssh_password,
            ssh_private_key=ssh_private_key,
            clear_ssh_password=clear_ssh_password == "1",
            clear_ssh_private_key=clear_ssh_private_key == "1",
        )
    except Exception as exc:  # noqa: BLE001
        return RedirectResponse(
            f"/admin/servers?flash=error:{exc}",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    return RedirectResponse("/admin/servers?flash=saved", status_code=status.HTTP_303_SEE_OTHER)


@router.get("/clients", response_class=HTMLResponse)
async def clients_page(
    request: Request,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin

    xui_panels = await xui_service.list_panels(db)
    xui_clients = await xui_service.list_all_site_clients(db)
    user_inbounds_by_panel: dict[int, list] = {}
    for panel in xui_panels:
        rows = await xui_service.list_user_inbounds(db, panel.id)
        user_inbounds_by_panel[panel.id] = [
            {
                "inbound_id": r.inbound_id,
                "protocol": r.protocol,
                "remark": r.remark,
                "port": r.port,
            }
            for r in rows
        ]
    panels_with_inbounds = [p for p in xui_panels if user_inbounds_by_panel.get(p.id)]

    return request.app.state.templates.TemplateResponse(
        "admin/clients.html",
        {
            "request": request,
            "admin": admin,
            "xui_panels": xui_panels,
            "xui_clients": xui_clients,
            "user_inbounds_by_panel": user_inbounds_by_panel,
            "panels_with_inbounds": panels_with_inbounds,
            "app_name": request.app.state.settings.app_name,
            "flash": request.query_params.get("flash"),
        },
    )


@router.post("/clients/xui")
async def create_xui_client_from_clients(
    request: Request,
    panel_id: int = Form(...),
    protocol: str = Form(...),
    email: str = Form(...),
    inbound_id: int = Form(...),
    total_gb: int = Form(0),
    limit_ip: int = Form(0),
    expiry_days: int = Form(30),
    start_after_first_use: str = Form(""),
    flow: str = Form(""),
    comment: str = Form(""),
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    panel = await db.get(XuiPanel, panel_id)
    if not panel:
        return RedirectResponse(
            "/admin/clients?flash=error:Панель не найдена",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    try:
        result = await xui_service.add_xui_client(
            db,
            panel,
            protocol=protocol,
            email=email.strip(),
            inbound_id=inbound_id,
            total_gb=total_gb,
            limit_ip=limit_ip,
            expiry_days=expiry_days,
            start_after_first_use=start_after_first_use == "1",
            flow=flow.strip(),
            comment=comment.strip(),
            require_user_available=True,
        )
    except Exception as exc:  # noqa: BLE001
        return RedirectResponse(
            f"/admin/clients?flash=error:{exc}",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    site_id = result.get("site_client_id")
    if site_id:
        return RedirectResponse(
            f"/admin/clients/xui/{site_id}?flash=created",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    return RedirectResponse(
        "/admin/clients?flash=created",
        status_code=status.HTTP_303_SEE_OTHER,
    )


@router.get("/clients/xui/{site_client_id}", response_class=HTMLResponse)
async def xui_site_client_detail(
    site_client_id: int,
    request: Request,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    row = await xui_service.get_site_client(db, site_client_id)
    if not row:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    stem, config = await xui_service.site_client_download_payload(row)
    return request.app.state.templates.TemplateResponse(
        "admin/xui_client_detail.html",
        {
            "request": request,
            "admin": admin,
            "client": row,
            "config": config,
            "filename_stem": stem,
            "app_name": request.app.state.settings.app_name,
            "flash": request.query_params.get("flash"),
        },
    )


@router.get("/clients/xui/{site_client_id}/config")
async def xui_site_client_config(
    site_client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    row = await xui_service.get_site_client(db, site_client_id)
    if not row:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    stem, config = await xui_service.site_client_download_payload(row)
    if not config:
        return RedirectResponse(
            f"/admin/clients/xui/{site_client_id}?flash=error:Нет конфига",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    ext = "conf" if row.protocol == "wireguard" else "txt"
    return Response(
        content=config,
        media_type="text/plain",
        headers={"Content-Disposition": f'attachment; filename="{stem}.{ext}"'},
    )


@router.get("/clients/xui/{site_client_id}/qr")
async def xui_site_client_qr(
    site_client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    row = await xui_service.get_site_client(db, site_client_id)
    if not row:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    _, config = await xui_service.site_client_download_payload(row)
    if not config:
        return Response(status_code=404)
    img = qrcode.make(config)
    buf = io.BytesIO()
    img.save(buf, format="PNG")
    buf.seek(0)
    return StreamingResponse(buf, media_type="image/png")


@router.get("/clients/xui/{site_client_id}/zip")
async def xui_site_client_zip(
    site_client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    row = await xui_service.get_site_client(db, site_client_id)
    if not row:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    stem, config = await xui_service.site_client_download_payload(row)
    if not config:
        return RedirectResponse(
            f"/admin/clients/xui/{site_client_id}?flash=error:Нет конфига",
            status_code=status.HTTP_303_SEE_OTHER,
        )
    ext = "conf" if row.protocol == "wireguard" else "txt"
    buf = io.BytesIO()
    with zipfile.ZipFile(buf, "w", compression=zipfile.ZIP_DEFLATED) as zf:
        zf.writestr(f"{stem}.{ext}", config)
        if row.protocol == "wireguard":
            zf.writestr(
                f"{stem}-info.txt",
                "\n".join(
                    [
                        f"Email: {row.email}",
                        f"Protocol: {row.protocol}",
                        f"Address: {row.address or ''}",
                        f"Endpoint: {row.endpoint or ''}",
                        f"DNS: {row.dns or ''}",
                        f"MTU: {row.mtu or ''}",
                        f"Panel: {row.panel.name if row.panel else ''}",
                        "",
                        "Import the .conf into WireGuard / AmneziaWG, or scan the QR on the panel.",
                        "",
                    ]
                ),
            )
        else:
            zf.writestr(
                f"{stem}-info.txt",
                "\n".join(
                    [
                        f"Email: {row.email}",
                        f"Protocol: {row.protocol}",
                        f"UUID: {row.uuid or ''}",
                        f"Flow: {row.flow or ''}",
                        "",
                        "Import the link into a VLESS client, or scan the QR on the panel.",
                        "",
                    ]
                ),
            )
    buf.seek(0)
    return Response(
        content=buf.getvalue(),
        media_type="application/zip",
        headers={"Content-Disposition": f'attachment; filename="{stem}.zip"'},
    )


@router.post("/clients/{client_id}/toggle")
async def toggle_client(
    client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    client = await db.get(VpnClient, client_id)
    if client:
        await vpn_service.set_client_enabled(db, client_id, not client.is_enabled)
    return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)


@router.post("/clients/{client_id}/delete")
async def remove_client(
    client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    await vpn_service.delete_client(db, client_id)
    return RedirectResponse("/admin/clients?flash=deleted", status_code=status.HTTP_303_SEE_OTHER)


@router.get("/clients/{client_id}", response_class=HTMLResponse)
async def client_detail(
    client_id: int,
    request: Request,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    result = await db.execute(
        select(VpnClient).options(selectinload(VpnClient.server)).where(VpnClient.id == client_id)
    )
    client = result.scalar_one_or_none()
    if not client:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    config = await vpn_service.get_client_config(db, client_id)
    return request.app.state.templates.TemplateResponse(
        "admin/client_detail.html",
        {
            "request": request,
            "admin": admin,
            "client": client,
            "config": config,
            "app_name": request.app.state.settings.app_name,
        },
    )


@router.get("/clients/{client_id}/config")
async def download_config(
    client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    client = await db.get(VpnClient, client_id)
    if not client:
        return RedirectResponse("/admin/clients", status_code=status.HTTP_303_SEE_OTHER)
    config = await vpn_service.get_client_config(db, client_id)
    filename = f"{client.name}.conf"
    return Response(
        content=config,
        media_type="text/plain",
        headers={"Content-Disposition": f'attachment; filename="{filename}"'},
    )


@router.get("/clients/{client_id}/qr")
async def client_qr(
    client_id: int,
    db: AsyncSession = Depends(get_db),
    admin=Depends(require_admin),
):
    if _is_redirect(admin):
        return admin
    config = await vpn_service.get_client_config(db, client_id)
    img = qrcode.make(config)
    buf = io.BytesIO()
    img.save(buf, format="PNG")
    buf.seek(0)
    return StreamingResponse(buf, media_type="image/png")