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

if get_exec_pars().source == CommandSource.ui:
    start   = -180.0
    stop    = 180.0
    step    = 20.0
    nb      = 5
    lat     = 1.0
    disp    = caget("SINBD01-DSCR010:DISPERSION-SIM")
    energy0 = caget("SINBD01-DSCR010:ENERGY-SIM")
else:
    start = args[0]
    stop  = args[1]
    step  = args[2]
    nb    = int(args[3])
    lat   = args[4]
    disp    = args[5]
    energy0 = args[6]

    
phase =  ControlledVariable("Phase", "SINEG01-RSYS:SET-VSUM-PHASE", "SINEG01-RSYS:SET-VSUM-PHASE")
phase.config.minValue   =-180.0
phase.config.maxValue   = 180.0
phase.config.resolution = 0.25
phase.initialize()

check_camtool()
camtool.start("SINBD01-DSCR010")

while camtool.stream.getChild("gr_x_fit_mean") == None:
    time.sleep(0.1)

x  = camtool.stream.getChild("gr_x_fit_mean")
dx  = camtool.stream.getChild("gr_x_fit_standard_deviation")

try:
    xb  = create_averager(x,  nb, -1)    # -1 event based, waits for the next value
    dxb = create_averager(dx, nb, -1)
    dxb.monitored=True     # not blocking, will return last nb values
    r = lscan(phase, [xb, dxb], start, stop, step , latency=lat)
    rf_phase = r.getPositions(0)
    E   = [energy0 * (1 + val.mean / 1e6 / disp) for val in r.getReadable(0)]
    dE  = [energy0 * (val.mean / 1e6 / disp) for val in r.getReadable(1)]
finally:
    phase.close()
    camtool.stop()   # stops camtool but does not close it camtool is a global object

p = plot(None, title="Output")[0]
p.clear()
p.addSeries(LinePlotSeries("Energy"))
p.addSeries(LinePlotSeries("Energy spread"))
p.getSeries(0).setData(to_array(rf_phase, 'd'), E)    
p.getSeries(1).setData(to_array(rf_phase, 'd'), dE)    
p.setLegendVisible(True)

set_return([E,dE])