"""
Arguments:

"""

MOTORS = [Eph]
POSITIONS = [400.0, 401.0]
LATENCY = 0.0

REGION1 = {'elo': 243.0, 'ehi': 245.0, 'estep': 0.1, 'epass': 50, 'tstep': 0.1, 'iter': 1, 'cis': True}
REGION2 = {'elo': 214.0, 'ehi': 217.0, 'estep': 0.1, 'epass': 50, 'tstep': 0.1, 'iter': 1, 'cis': False}
REGIONS = [REGION1, REGION2]

CLOSE_SHUTTER_AT_END = True

Scienta.setAcquisitionMode(ch.psi.pshell.epics.Scienta.AcquisitionMode.Swept)

class SpectrumReader(ReadonlyRegisterBase, ReadonlyRegisterArray):
    def initialize(self):
        super(SpectrumReader, self).initialize()
        
        self.channel_begin_dataset_name = "scan{0}/ScientaChannelBegin{1}".format(self.scan_index + 1, self.region_index + 1)
        self.channel_end_dataset_name = "scan{0}/ScientaChannelEnd{1}".format(self.scan_index + 1, self.region_index + 1)
        create_dataset(self.channel_begin_dataset_name, 'd')
        create_dataset(self.channel_end_dataset_name, 'd')
        
    def setup(self):
        ephot = Eph.read()
        try:
            if self.region['cis']:
                edelta = ephot - self.ephot_start
            else:
                edelta = 0.0
        except AttributeError:
            self.ephot_start = ephot
            edelta = 0.0
        elo = self.region['elo'] + edelta
        ehi = self.region['ehi'] + edelta

        Scienta.lowEnergy.write(elo)
        Scienta.highEnergy.write(ehi)
        Scienta.stepSize.write(self.region['estep'])
        Scienta.setPassEnergy(self.region['epass'])
        Scienta.stepTime.write(self.region['tstep'])
        Scienta.setIterations(self.region['iter'])

        append_dataset(self.channel_begin_dataset_name, elo)
        append_dataset(self.channel_end_dataset_name, ehi)

    def read(self):
        self.setup()
        print "Photon energy {ephot} eV. Acquiring spectrum {elo}-{ehi} eV.".format(ephot=Eph.read(), elo=Scienta.lowEnergy.value, ehi=Scienta.highEnergy.value)
        trig_scienta()
        time.sleep(0.5)
        sp = Scienta.getSpectrum().read()
        return sp

    def getSize(self):
        nx = int((self.region['ehi'] - self.region['elo']) / self.region['estep']) + 1
        return nx


class ImageReader(ReadonlyRegisterBase, ReadonlyRegisterMatrix):   
    def read(self):
        return Scienta.getDataMatrix().read()

    def getWidth(self):
        nx = int((self.region['ehi'] - self.region['elo']) / self.region['estep']) + 1
        return nx

    def getHeight(self):
        ny = Scienta.slices.read()
        return ny

scan_index = -1

def do_scan(motors, positions, regions, latency):
    sensors = [SampleCurrent, RefCurrent]
    scan_index += 1
    
    for (index, region) in enumerate(regions):
        reader = SpectrumReader()
        reader.scan_index = scan_index
        reader.region_index = index
        reader.region = region
        reader.initialize()
        set_device_alias(reader, "ScientaSpectrum{0}".format(index + 1))
        sensors.append(reader)

        image = ImageReader()
        image.region_index = index
        image.region = region
        image.initialize()
        set_device_alias(image, "ScientaImage{0}".format(index + 1))
        sensors.append(image)

    adjust_sensors()
    set_adc_averaging()

    vscan(motors, sensors, positions, True, latency,False, before_read=wait_beam, after_read = after_readout)


try:
    set_preference(Preference.PLOT_TYPES, {'Scienta spectrum':1})
    do_scan(MOTORS, POSITIONS, REGIONS, LATENCY)
finally:
    if CLOSE_SHUTTER_AT_END:
        after_scan()