"""网络管理路由"""
from fastapi import APIRouter, HTTPException, Query
from pydantic import BaseModel, Field
from typing import Optional, List
from lxml import etree

from app.libvirt_conn import conn_pool
import libvirt

router = APIRouter()


class NetworkCreate(BaseModel):
    name: str = Field(..., description="网络名称")
    mode: str = Field("nat", description="模式: nat/bridge/isolated")
    subnet: str = Field("192.168.100.0/24", description="子网")
    bridge: Optional[str] = Field(None, description="桥接网卡名(mode=bridge时必填)")
    dhcp_start: Optional[str] = Field(None, description="DHCP起始IP")
    dhcp_end: Optional[str] = Field(None, description="DHCP结束IP")


@router.get("/list")
async def list_networks(host_id: str = Query("local")):
    """列出所有网络"""
    conn = conn_pool.get_conn(host_id)
    networks = conn.listAllNetworks(0)
    result = []
    for net in networks:
        xml = etree.fromstring(net.XMLDesc(0).encode())

        forward = xml.find("forward")
        mode = forward.get("mode", "isolated") if forward is not None else "isolated"

        ip_elem = xml.find("ip")
        address = ip_elem.get("address", "") if ip_elem is not None else ""
        netmask = ip_elem.get("netmask", "") if ip_elem is not None else ""

        bridge = xml.find("bridge")
        bridge_name = bridge.get("name", "") if bridge is not None else ""

        dhcp_range = None
        dhcp = xml.find(".//dhcp")
        if dhcp is not None:
            r = dhcp.find("range")
            if r is not None:
                dhcp_range = {"start": r.get("start", ""), "end": r.get("end", "")}

        leases = []
        try:
            for lease in net.DHCPLeases():
                leases.append({
                    "ip": lease.get("ipaddr", ""),
                    "mac": lease.get("mac", ""),
                    "hostname": lease.get("hostname", ""),
                    "expiry": lease.get("expirytime", 0),
                })
        except Exception:
            pass

        result.append({
            "name": net.name(),
            "active": net.isActive() == 1,
            "persistent": net.isPersistent() == 1,
            "autostart": net.autostart() == 1,
            "mode": mode,
            "address": address,
            "netmask": netmask,
            "bridge": bridge_name,
            "dhcp": dhcp_range,
            "leases": leases,
        })
    return {"networks": result, "total": len(result)}


@router.get("/detail/{name}")
async def get_network(name: str, host_id: str = Query("local")):
    """获取网络详情"""
    conn = conn_pool.get_conn(host_id)
    try:
        net = conn.networkLookupByName(name)
    except libvirt.libvirtError:
        raise HTTPException(status_code=404, detail=f"网络 '{name}' 不存在")

    xml_str = net.XMLDesc(0)
    return {"name": name, "xml": xml_str, "active": net.isActive() == 1}


@router.post("/create")
async def create_network(net: NetworkCreate, host_id: str = Query("local")):
    """创建网络"""
    if net.mode == "bridge" and not net.bridge:
        raise HTTPException(status_code=400, detail="桥接模式必须指定桥接网卡")

    if net.mode == "bridge":
        xml = f"""<network>
  <name>{net.name}</name>
  <forward mode='bridge'/>
  <bridge name='{net.bridge}'/>
</network>"""
    else:
        import ipaddress
        network = ipaddress.ip_network(net.subnet, strict=False)
        gateway = str(network.network_address + 1)

        dhcp_xml = ""
        if net.mode == "nat":
            start = net.dhcp_start or str(network.network_address + 2)
            end = net.dhcp_end or str(network.network_address + 254)
            dhcp_xml = f"""
    <dhcp>
      <range start='{start}' end='{end}'/>
    </dhcp>"""

        forward_xml = f"<forward mode='{net.mode}'/>" if net.mode == "nat" else ""
        netmask = str(network.netmask)

        xml = f"""<network>
  <name>{net.name}</name>
  {forward_xml}
  <bridge name='virbr-{net.name[:8]}' stp='on' delay='0'/>
  <ip address='{gateway}' netmask='{netmask}'>{dhcp_xml}
  </ip>
</network>"""

    with conn_pool.get_rw(host_id) as rw_conn:
        try:
            n = rw_conn.networkDefineXML(xml)
            n.setAutostart(1)
            n.create()
            return {"message": f"网络 '{net.name}' 创建成功"}
        except libvirt.libvirtError as e:
            raise HTTPException(status_code=500, detail=f"创建网络失败: {str(e)}")


@router.delete("/delete/{name}")
async def delete_network(name: str, host_id: str = Query("local")):
    """删除网络"""
    with conn_pool.get_rw(host_id) as rw_conn:
        try:
            net = rw_conn.networkLookupByName(name)
        except libvirt.libvirtError:
            raise HTTPException(status_code=404, detail=f"网络 '{name}' 不存在")

        if net.isActive():
            net.destroy()
        net.undefine()
        return {"message": f"网络 '{name}' 已删除"}


@router.post("/action/{name}")
async def network_action(name: str, action: str, host_id: str = Query("local")):
    """网络操作: start/stop"""
    with conn_pool.get_rw(host_id) as rw_conn:
        try:
            net = rw_conn.networkLookupByName(name)
        except libvirt.libvirtError:
            raise HTTPException(status_code=404, detail=f"网络 '{name}' 不存在")

        try:
            if action == "start":
                net.create()
            elif action == "stop":
                net.destroy()
            else:
                raise HTTPException(status_code=400, detail=f"不支持的操作: {action}")
            return {"message": f"网络 '{name}' {action} 成功"}
        except libvirt.libvirtError as e:
            raise HTTPException(status_code=500, detail=f"操作失败: {str(e)}")