import  ch.psi.pshell.epics.ControlledVariable as ControlledVariable

if get_exec_pars().source == CommandSource.ui:
    start   = -10.0
    stop    = 180.0
    step    = 5.0
    nb      = 3
    lat     = 0.300
else:
    start = args[0]
    stop  = args[1]
    step  = args[2]
    nb    = int(args[3])
    lat   = args[4]

bphase = ControlledVariable("Beam phase", "SINEG01-RSYS:SET-BEAM-PHASE", "SINEG01-RSYS:GET-BEAM-PHASE")
bphase.config.minValue   =-180.0
bphase.config.maxValue   = 360.0
bphase.config.precision  = 3
bphase.config.resolution = 1.0
bphase.config.save()
bphase.initialize()
st = Stream("Schottky", dispatcher)
q       = st.addScalar("Charge",   "SINEG01-DICT215:B1_CHARGE",   1, 0)
st.initialize()
st.start()
rphase  = Channel("SINEG01-RSYS:GET-VSUM-PHASE", type = 'd', alias = 'RF phase')
bphase0 = bphase.read()

try:
    q_averager      = create_averager(q, nb, 0.100)
    rphase_averager = create_averager(rphase, nb, 0.100)
    r = lscan(bphase, (q_averager, rphase_averager), start, stop, step, latency=lat)
    beamphase  = r.getPositions(0)
    charge     = [val.mean for val in r.getReadable(0)]
    chargerms  = [val.stdev for val in r.getReadable(0)]
    rfphase    = [val.mean for val in r.getReadable(1)]
    rfphaserms = [val.stdev for val in r.getReadable(1)]
finally:
    bphase.write(phase0)
    bphase.close()
    st.close()
    q.close()
    rphase.close()

#Setting the return value
index_max = charge.index(max(charge))
rphase_ref = rfphase[index_max] - 80

set_return(rphase_ref)

# save the entry in the logbook
#if get_option("Generated data file:\n" + get_exec_pars().path +"\n\n" + "Save to ELOG?", "YesNo") == "Yes":
#    log_msg =           "Start:        %0.1f"   % start   + "deg\n"
#    log_msg = log_msg + "Stop:         %0.1f"   % stop    + "deg\n"
#    log_msg = log_msg + "Step:         %0.1f"   % nb      + "deg\n"
#    log_msg = log_msg + "Nb samples:   %0.0f"   % nb      + "\n"
#    log_msg = log_msg + "Latency:      %0.3f"   % lat     + "s\n"
#    log_msg = log_msg + "Data file:    " + get_exec_pars().path
#    elog("Schottky Scan", log_msg, get_plot_snapshots())