import enum
from dataclasses import dataclass

class LcrConnException(Exception):
    """The exception thrown by LCR Connector"""
    pass


class DeviceKind(enum.IntEnum):
    """The kind of device"""
    
    RESISTOR = enum.auto()
    """Resistor device"""
    CAPACITOR = enum.auto()
    """Capacitor device"""
    INDUCTOR = enum.auto()
    """Inductor device"""


class JointKind(enum.IntEnum):
    """The joint type between 2 devices"""
    
    SERIES = enum.auto()
    """Series connection"""
    PARALLEL = enum.auto()
    """Parallel connection"""
    
    def flip(self) -> 'JointKind':
        """
        Flip the joint kind
        
        Flip the joint kind from series to parallel or vice versa

        :return: The flipped joint kind
        """
        match self:
            case JointKind.SERIES:
                return JointKind.PARALLEL
            case JointKind.PARALLEL:
                return JointKind.SERIES


@dataclass
class CircuitJoint:
    """The part of circuit composed of two devices and the joint kind"""

    device_value: float
    """The value of the device"""
    joint_kind: JointKind
    """The joint kind between this device and the next device"""
    
    def compute(self, value: float,  device_kind: DeviceKind) -> float:
        """
        Compute the joint value

        :param value: The value computed from previous devices
        :param device_kind: The kind of the device
        :return: The joint value computed
        """
        if self.device_value <= 0 or value <= 0:
            raise LcrConnException("Device value must be greater than 0")
        
        # We perform series connect for: series resistor, series inductor and parallel capacitor.
        # We perform parallel connect for: parallel resistor, parallel inductor and series capacitor.
        joint_kind = self.joint_kind
        if device_kind == DeviceKind.CAPACITOR:
            joint_kind = joint_kind.flip()

        match joint_kind:
            case JointKind.SERIES:
                return self.device_value + value
            case JointKind.PARALLEL:
                return (self.device_value * value) / (self.device_value + value)


class Circuit:
    """The circuit composed of multiple joints"""

    device_value: float
    """The value of the first device"""
    joints: list[CircuitJoint]
    """The joints between devices"""

    def __init__(self, value: float):
        self.device_value = value
        self.joints = []

    def add_joint(self, joint: CircuitJoint):
        self.joints.append(joint)

    def len_devices(self) -> int:
        return len(self.joints) + 1

    def compute(self, device_kind: DeviceKind) -> float:
        """
        Compute the circuit value

        :param device_kind: The kind of the device
        :return: The circuit value
        """
        if self.device_value <= 0:
            raise LcrConnException("Device value must be greater than 0")
        
        value = self.device_value
        for joint in self.joints:
            value = joint.compute(value, device_kind)
        return value
        

def from_human_readable_value(strl: str) -> float:
    """
    Convert human readable value to float

    :param strl: The human readable value
    :return: The parsed float value
    :raises ValueError: If the input string is not a valid number
    """
    strl = strl.strip()

    if strl.endswith('n'):
        return float(strl[0:-1]) * 1e-12
    if strl.endswith('p'):
        return float(strl[0:-1]) * 1e-9
    if strl.endswith('u'):
        return float(strl[0:-1]) * 1e-6
    if strl.endswith('m'):
        return float(strl[0:-1]) * 1e-3
    if strl.endswith('k'):
        return float(strl[0:-1]) * 1e3
    if strl.endswith('M'):
        return float(strl[0:-1]) * 1e6
    if strl.endswith('G'):
        return float(strl[0:-1]) * 1e9
    return float(strl)



def to_human_readable_value(v: float) -> str:
    """
    Convert float value to human readable value

    :param value: The float value
    :return: The human readable value
    """
    if v / 1e-12 < 1e3:
        return "{:e} n".format(v / 1e-12)
    if v / 1e-9 < 1e3:
        return "{:.4f} p".format(v / 1e-9)
    if v / 1e-6 < 1e3:
        return "{:.4f} u".format(v / 1e-6)
    if v / 1e-3 < 1e3:
        return "{:.4f} m".format(v / 1e-3)
    if v < 1e3:
        return "{:.4f}".format(v)
    if v / 1e3 < 1e3:
        return "{:.4f} k".format(v / 1e3)
    if v / 1e6 < 1e3:
        return "{:.4f} M".format(v / 1e6)
    if v / 1e9 < 1e3:
        return "{:.4f} G".format(v / 1e9)

    return "{:e}".format(v)