r"""Use of reference_circuit_builder to prepare a circuit for a multireference state."""

# imports
from math import sqrt

from inquanto.ansatzes import (
    multi_configuration_preparator,
    multi_configuration_preparator_sparse,
    reference_circuit_builder,
    CircuitAnsatz,
)
from inquanto.states import QubitState, QubitStateString

# 2 basis states, 4 qubits
# we set our coefficients here so that the multiconfigstate will be normalized
qss_1, coeff_qss1 = QubitStateString([1, 1, 0, 0]), sqrt(3 / 4)
qss_2, coeff_qss2 = QubitStateString([0, 0, 1, 1]), sqrt(1 / 4)

qubit_states = QubitState(
    {
        qss_1: coeff_qss1,
        qss_2: coeff_qss2,
    }
)

# We can create a non-symbolic circuit corresponding to the linear combination of terms within the qubit_states.
# We can do this using either multi_configuration_preparator (MultiConfigurationState),
# or using multi_configuration_preparator_sparse (MultiConfigurationStateSparse).


print("\nCircuit created by MultiConfigurationState")
multi_state_circ = reference_circuit_builder(
    qubit_states, multireference_builder=multi_configuration_preparator
)

# Here an Ansatz is constructed from multi_state_circ to make use of InQuanto's ansatz features
ref_circ_ansatz = CircuitAnsatz(multi_state_circ)
print("Ansatz report:\n", ref_circ_ansatz.generate_report())
print("Circuit resources:", ref_circ_ansatz.circuit_resources())
print("Dataframe of state vector:\n", ref_circ_ansatz.df_numeric())


print("\nCircuit created by MultiConfigurationStateSparse")
multi_state_circ_sparse = reference_circuit_builder(
    qubit_states, multireference_builder=multi_configuration_preparator_sparse
)

# Here an Ansatz is constructed from multi_state_circ_sparse to make use of InQuanto's ansatz features
ref_circ_ansatz_sparse = CircuitAnsatz(multi_state_circ_sparse)
print("Ansatz report:\n", ref_circ_ansatz_sparse.generate_report())
print("Circuit resources:", ref_circ_ansatz_sparse.circuit_resources())
print("Dataframe of state vector:\n", ref_circ_ansatz_sparse.df_numeric())