"""虚拟机 XML 模板和工具函数"""
import uuid
import libvirt
from lxml import etree


def generate_vm_xml(
    name: str,
    memory_mb: int,
    vcpus: int,
    disk_path: str,
    disk_size_gb: int = 20,
    iso_path: str = None,
    network: str = "default",
    vnc_port: int = -1,
    os_type: str = "hvm",
    arch: str = "x86_64",
    machine: str = "pc",
) -> str:
    """生成虚拟机 XML 定义"""

    vm_uuid = str(uuid.uuid4())

    # 基础 XML 结构
    xml_parts = f"""<domain type='kvm'>
  <name>{name}</name>
  <uuid>{vm_uuid}</uuid>
  <memory unit='MiB'>{memory_mb}</memory>
  <currentMemory unit='MiB'>{memory_mb}</currentMemory>
  <vcpu placement='static'>{vcpus}</vcpu>
  <os>
    <type arch='{arch}' machine='{machine}'>{os_type}</type>
    <boot dev='hd'/>
    <boot dev='cdrom'/>
  </os>
  <features>
    <acpi/>
    <apic/>
  </features>
  <cpu mode='host-passthrough'/>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>destroy</on_crash>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='qcow2'/>
      <source file='{disk_path}'/>
      <target dev='vda' bus='virtio'/>
    </disk>"""

    # 光驱（ISO安装）
    if iso_path:
        xml_parts += f"""
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='{iso_path}'/>
      <target dev='hda' bus='ide'/>
      <readonly/>
    </disk>"""

    # VNC
    if vnc_port == -1:
        vnc_port = 5900  # auto-allocate by libvirt
    xml_parts += f"""
    <graphics type='vnc' port='{vnc_port}' autoport='yes' listen='0.0.0.0' passwd=''>
      <listen type='address' address='0.0.0.0'/>
    </graphics>
    <video>
      <model type='virtio' heads='1' primary='yes'/>
    </video>
    <serial type='pty'>
      <target port='0'/>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>"""

    # 网络
    xml_parts += f"""
    <interface type='network'>
      <source network='{network}'/>
      <model type='virtio'/>
    </interface>
    <controller type='usb' model='qemu-xhci'/>
    <input type='tablet' bus='usb'/>
    <memballoon model='virtio'/>
  </devices>
</domain>"""

    return xml_parts


def parse_vm_info(dom) -> dict:
    """从 libvirt domain 对象提取虚拟机信息"""
    from app.libvirt_conn import libvirt_conn

    # 基本信息
    info = {
        "id": dom.ID(),
        "name": dom.name(),
        "uuid": dom.UUIDString(),
        "state": _get_state(dom),
        "autostart": False,
    }

    try:
        info["autostart"] = dom.autostart() == 1
    except Exception:
        pass

    # 解析 XML
    xml_desc = dom.XMLDesc(0)
    tree = etree.fromstring(xml_desc.encode())

    # 内存和CPU
    mem = tree.find(".//memory")
    cur_mem = tree.find(".//currentMemory")
    vcpu = tree.find(".//vcpu")

    mem_unit = mem.get("unit", "KiB") if mem is not None else "KiB"
    mem_val = int(mem.text) if mem is not None else 0
    info["memory_mb"] = _to_mb(mem_val, mem_unit)

    cur_unit = cur_mem.get("unit", "KiB") if cur_mem is not None else "KiB"
    cur_val = int(cur_mem.text) if cur_mem is not None else 0
    info["current_memory_mb"] = _to_mb(cur_val, cur_unit)

    info["vcpus"] = int(vcpu.text) if vcpu is not None else 1

    # CPU type
    cpu = tree.find(".//cpu")
    if cpu is not None:
        info["cpu_mode"] = cpu.get("mode", "unknown")
    else:
        info["cpu_mode"] = "unknown"

    # 磁盘
    disks = []
    for disk in tree.findall(".//disk"):
        if disk.get("device") == "disk":
            source = disk.find("source")
            target = disk.find("target")
            driver = disk.find("driver")
            disk_info = {
                "file": source.get("file", "") if source is not None else "",
                "dev": target.get("dev", "") if target is not None else "",
                "bus": target.get("bus", "") if target is not None else "",
                "format": driver.get("type", "") if driver is not None else "",
            }
            disks.append(disk_info)
    info["disks"] = disks

    # 网络
    interfaces = []
    for iface in tree.findall(".//interface"):
        source = iface.find("source")
        model = iface.find("model")
        iface_info = {
            "type": iface.get("type", ""),
            "network": source.get("network", "") if source is not None else "",
            "model": model.get("type", "") if model is not None else "",
        }
        # 如果运行中，获取MAC和IP
        if info["state"] == "running":
            mac = iface.find("mac")
            if mac is not None:
                iface_info["mac"] = mac.get("address", "")
            # 尝试获取IP地址
            try:
                ifaces = dom.interfaceAddresses(
                    libvirt.VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_AGENT, 0
                )
                if ifaces:
                    for ifname, ifdata in ifaces.items():
                        if mac is not None and ifdata.get("hwaddr", "") == iface_info.get("mac", ""):
                            addrs = ifdata.get("addrs", [])
                            if addrs:
                                iface_info["ip"] = addrs[0].get("addr", "")
            except Exception:
                try:
                    ifaces = dom.interfaceAddresses(
                        libvirt.VIR_DOMAIN_INTERFACE_ADDRESSES_SRC_LEASE, 0
                    )
                    if ifaces:
                        for ifname, ifdata in ifaces.items():
                            addrs = ifdata.get("addrs", [])
                            if addrs:
                                iface_info["ip"] = addrs[0].get("addr", "")
                                break
                except Exception:
                    pass
        interfaces.append(iface_info)
    info["interfaces"] = interfaces

    # VNC
    graphics = tree.find(".//graphics[@type='vnc']")
    if graphics is not None:
        info["vnc_port"] = int(graphics.get("port", -1))
        info["vnc_listen"] = graphics.get("listen", "127.0.0.1")
    else:
        info["vnc_port"] = -1
        info["vnc_listen"] = ""

    # OS info
    os_type = tree.find(".//os/type")
    info["os_type"] = os_type.text if os_type is not None else "hvm"

    return info


def _get_state(dom) -> str:
    """获取虚拟机运行状态"""
    raw = dom.info()
    state = raw[0]
    state_map = {
        libvirt.VIR_DOMAIN_NOSTATE: "nostate",
        libvirt.VIR_DOMAIN_RUNNING: "running",
        libvirt.VIR_DOMAIN_BLOCKED: "blocked",
        libvirt.VIR_DOMAIN_PAUSED: "paused",
        libvirt.VIR_DOMAIN_SHUTDOWN: "shutdown",
        libvirt.VIR_DOMAIN_SHUTOFF: "shutoff",
        libvirt.VIR_DOMAIN_CRASHED: "crashed",
        libvirt.VIR_DOMAIN_PMSUSPENDED: "suspended",
    }
    return state_map.get(state, "unknown")


def _to_mb(value, unit) -> int:
    """转换为 MB"""
    unit = unit.lower()
    if unit in ("kib", "k", "kib"):
        return value // 1024
    elif unit in ("mib", "m", "mib"):
        return value
    elif unit in ("gib", "g", "gib"):
        return value * 1024
    elif unit in ("tib", "t"):
        return value * 1024 * 1024
    elif unit == "b":
        return value // (1024 * 1024)
    return value // 1024  # default KiB