"""
Copyright 2024 Entropica Labs Pte Ltd
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
"""
from enum import Enum
from typing import Optional
from uuid import uuid4
from pydantic import Field, field_validator, ValidationInfo
from pydantic.dataclasses import dataclass
from .utilities.validation_tools import (
dataclass_config,
uuid_error,
ValidationInfo,
)
[docs]
class ChannelType(str, Enum):
"""
The type of the channel: QUANTUM or CLASSICAL
More types should be added when we feel the need for it
"""
QUANTUM = "quantum"
CLASSICAL = "classical"
[docs]
def create_default_label(channel_type: ChannelType):
"""
Creates a default label for the channel.
Parameters
----------
channel_type : ChannelType
The type of the channel: QUANTUM or CLASSICAL
Returns
-------
str
The default label for the channel
"""
match channel_type:
case ChannelType.QUANTUM:
return "data_qubit"
case ChannelType.CLASSICAL:
return "classical_bit"
case _:
raise ValueError(f"Channel type {type} not recognized")
[docs]
@dataclass(config=dataclass_config)
class Channel:
"""
Identifies information channels connecting the Circuit elements: examples are
classical or quantum bit channels
Parameter
---------
type: ChannelType
The type of the channel: QUANTUM or CLASSICAL, default is QUANTUM
label: str
The label of the channel, allowing it to be grouped in a user friendly way, E.g.
can be "red", "ancilla_qubit" or "my_favourite_qubit"
id: str
The unique identifier of the channel
"""
type: ChannelType = Field(default=ChannelType.QUANTUM)
label: Optional[str] = Field(default=None, validate_default=True)
id: str = Field(default_factory=lambda: str(uuid4()))
# Validation functions
_validate_uuid = field_validator("id")(uuid_error)
[docs]
@field_validator("label", mode="after")
@classmethod
def set_default_label(cls, v: str, info: ValidationInfo) -> str:
"""
Set the default label based on the type of the channel, according to
the following scheme:
ChannelType.QUANTUM: "data_qubit"
ChannelType.CLASSICAL: "classical_bit"
"""
if v is None and "type" in info.data.keys():
v = create_default_label(info.data["type"])
return v
# Magic methods
def __eq__(self, other):
if isinstance(other, Channel):
return (self.type, self.id) == (other.type, other.id)
return NotImplemented
def __hash__(self) -> int:
return hash((self.type, self.id))
# Convenience methods
[docs]
def is_quantum(self) -> bool:
"""Check if the channel is a quantum channel.
Returns
-------
bool
True if the channel is a quantum channel, False otherwise.
"""
return self.type == ChannelType.QUANTUM
[docs]
def is_classical(self) -> bool:
"""Check if the channel is a classical channel.
Returns
-------
bool
True if the channel is a classical channel, False otherwise.
"""
return self.type == ChannelType.CLASSICAL