# -*- coding: utf-8 -*-
"""
Created on Sep 14 17:42:42 2021
@author: tuema
"""

print('HSK qiskit Exercises')

#---------------------------------------------------------------------------
#imports
from qiskit import QuantumCircuit, transpile
from qiskit.providers.basic_provider import BasicSimulator
from qiskit.visualization import plot_histogram,plot_bloch_multivector
from qiskit.quantum_info import Statevector
from qiskit import QuantumCircuit,QuantumRegister,ClassicalRegister



#ploting
import matplotlib.pyplot as plt

#math
import numpy as np


###############################################################
# Make a quantum circuit for
#Error Considerations using the u gate and simulate an error
#by adding noise
###############################################################

iterat = 100

num_qubits = 1
q = QuantumRegister(num_qubits)
c = ClassicalRegister(num_qubits)
qc = QuantumCircuit(q,c)


bdelta = np.pi/180
#bdelta = 0
pdelta = np.pi/180
#pdelta = 0

randaver = 0


# 0 < theta < pi
theta0 = np.pi/4
# 0 < phi < 2pi
phi0 = np.pi/2
# 0 < lam < 2pi
lam0 = 0

# 0 < theta < pi
thetad0 = theta0
# 0 < phi < 2pi
phid0 = np.pi - lam0
# 0 < lam < 2pi
lamd0 = (-1)*phi0 





# Create a test circuit


#qc.h(0)

qc.barrier()

#Apply U dagger
#Have to do a phase shift with the p gate to get complete transformation

for i in range(iterat):
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    theta=theta0+(rand * bdelta)
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    phi=phi0+(rand * pdelta)
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    lam=lam0+(rand * pdelta)
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    thetad=thetad0+(rand * bdelta)
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    phid=phid0+(rand * pdelta)
    rand0=np.random.rand()
    rand1=np.random.randint(2)
    rand=rand0 * ((-1)**rand1)
    randaver = randaver + rand
    lamd=lamd0+(rand * pdelta)
    
#    print('i:',i)
#    print('Delta theta:',theta-theta0)
#    print('Delta phi:',phi-phi0)
#    print('Delta lam:',lam-lam0)
#    print('Delta thetad:',thetad-thetad0)
#    print('Delta phid:',phid-phid0)
#    print('Delta lamd:',lamd-lamd0)
    
    
    qc.u(theta,phi,lam,q)
    qc.p(-np.pi,q)
    qc.u(thetad,phid,lamd,q)




qc.barrier()

#qc.h(0)


# Measure 
qc.measure(q[0],c[0])
    
#---------------------------------------------------------------------------
#draw
qc.draw("mpl")
plt.show()    
    
#sv=Statevector(qc)
#plot_bloch_multivector(sv)
#plt.show() 

   
#Simulate the Quantum Circuit
sim_backend = BasicSimulator()
job = sim_backend.run(transpile(qc, sim_backend), shots=1024)
result = job.result()

counts = result.get_counts(qc)
count0 = counts.get('0')
count1 = counts.get('1')
randaver = randaver/iterat

print('----------------------------')
print("Basic simulator : ")
print(result.get_counts(qc))



print('randaver   :',randaver)
print('Count 0    :',count0)
print('Count 1    :',count1)


        


#---------------------------------------------------------------------------
#plot
counts = result.get_counts(qc)
legend = ['First execution']
plot_histogram([counts], legend=legend, color=['midnightblue'],
                title="HSK Base Circuit 3")
plt.show()



#---------------------------------------------------------------------------
#end