from etcd3_wrapper import EtcdEntry
from .helpers import SpecificEtcdEntryBase


class VMStatus(object):
    # Must be only assigned to brand new VM
    requested_new = "REQUESTED_NEW"

    # Host assigned to VM but not created yet.
    scheduled_deploy = "SCHEDULED_DEPLOY"

    # Only Assigned to already created vm
    requested_start = "REQUESTED_START"

    # These all are for running vms
    requested_shutdown = "REQUESTED_SHUTDOWN"
    requested_suspend = "REQUESTED_SUSPEND"
    requested_resume = "REQUESTED_RESUME"
    requested_migrate = "REQUESTED_MIGRATE"

    # either its image is not found or user requested
    # to delete it
    deleted = "DELETED"
    
    stopped = "STOPPED"  # After requested_shutdown
    killed = "KILLED"  # either host died or vm died itself

    running = "RUNNING"
    suspended = "SUSPENDED"


RUNNING_VM_STATUSES = [VMStatus.requested_shutdown, VMStatus.requested_suspend,
                       VMStatus.requested_resume, VMStatus.requested_migrate,
                       VMStatus.running, VMStatus.suspended]


class VMEntry(SpecificEtcdEntryBase):
    def __init__(self, e: EtcdEntry):
        self.owner = ""
        self.specs = dict()
        self.hostname = ""
        self.status = ""
        self.image_uuid = ""
        
        super().__init__(e)
   
    @property
    def uuid(self):
        return self.key.split("/")[-1]

    def declare_killed(self):
        self.hostname = ""
        if self.status in RUNNING_VM_STATUSES:
            self.status = VMStatus.killed


class VmPool(object):
    def __init__(self, etcd_client, vm_prefix):
        self.client = etcd_client
        self.prefix = vm_prefix

    @property
    def vms(self):
        _vms = self.client.get_prefix(self.prefix, value_in_json=True)
        return [VMEntry(vm) for vm in _vms]

    def by_host(self, host, _vms=None):
        if _vms is None:
            _vms = self.vms
        return list(filter(lambda x: x.hostname == host, _vms))

    def by_status(self, status, _vms=None):
        if _vms is None:
            _vms = self.vms
        return list(filter(lambda x: x.status == status, _vms))

    def except_status(self, status, _vms=None):
        if _vms is None:
            _vms = self.vms
        return list(filter(lambda x: x.status != status, _vms))

    def get(self, key):
        v = self.client.get(key, value_in_json=True)
        return VMEntry(v)
    
    def put(self, obj: VMEntry):
        self.client.put(obj.key, obj.value, value_in_json=True)