# Tool to align the solenoid on the gun.
# S. Bettoni, A. Gobbo, D. Voulot
# 30/05/2016

# Procedure:
    # switch off all the magnets between the gun solenoid and the screen or BPM used for the measurement
    # change the current of the gun soleoid
    # look at the centroid position (BPM or screen) downstream of the gun.

I_set = Channel("SINEG01-MSOL130:I-SET")
I_get = Channel("SINEG01-MSOL130:I-READ")
# cam_x, cam_y = ...       # some camtool command / channel?
bpm_x = ai1                # Channel("SINEG01-DBPM340:X1")
bpm_y = ai2                # Channel("SINEG01-DBPM340:Y1")

def ccr(mag):
    n = 1
    while n > 0:
        sleep(0.5)
        n = caget(mag + ":I-COMP")
def laser_on():
    print(laser_on)    #caput("SIN-CVME-TIMAST-TMA:LaserDelayControl", 0)
def laser_off():
    print(laser_off)    #caput("SIN-CVME-TIMAST-TMA:LaserDelayControl", 1)

I1 = 2.0
I2 = 5.0
dI = 0.5

# Switch off magnets
mag = ["SINEG01-MCRX120","SINEG01-MCRY120"]
for m in mag:
    caput(m + ":I-SET", 0.0)
for m in mag:
    ccr(m)

# Scan using the screen
#r = lscan(I_set, [I_get, cam_x, cam_y], I1, I2, dI, passes = 2, zigzag = True)
# Scan using the BPM
r = lscan(I_set, [I_get, bpm_x, bpm_y], I1, I2, dI, 1.0, before_read = laser_on(), after_read = laser_off())

# take the result of the scan and do the plots
plot(r.getReadable(2), xdata=r.getReadable(1), title = "Centroid excursion")

# save the entry in the logbook
msg = str(r)
msg = msg + "\nFile: " + get_exec_pars().path
msg = msg + "\n\n" + r.print()
elog("Gun solenoid current scan", msg , get_plot_snapshots())