from cil.framework import DataProcessor, ImageData
import numpy as np

import gi
gi.require_version('Ufo','0.0')
from gi.repository import Ufo

class FBP_Standard(DataProcessor):
    def __init__(self, volume_geometry,
                 sinogram_geometry,
                 z_dim = None):

        kwargs = {
            'volume_geometry': volume_geometry,
            'sinogram_geometry': sinogram_geometry,
            'z_dim': z_dim}

        super(FBP_Standard, self).__init__(**kwargs)

        self.z_dim = 0
        self.set_ImageGeometry(volume_geometry)
        self.set_AcquisitionGeometry(sinogram_geometry)

    def check_input(self, dataset):
        if self.sinogram_geometry.dimension == '2D':
            self.z_dim = 1
        elif self.sinogram_geometry.dimension == '3D':
            self.z_dim = self.sinogram_geometry.shape[2]

        return True

    def set_ImageGeometry(self, volume_geometry):
        self.volume_geometry = volume_geometry

    def set_AcquisitionGeometry(self, sinogram_geometry):
        self.sinogram_geometry = sinogram_geometry

    def process(self, **kwargs):
        # Get DATA
        DATA = self.get_input()
        DATA = DATA.as_array()

        pm = Ufo.PluginManager()
        graph = Ufo.TaskGraph()
        scheduler = Ufo.Scheduler()

        read = pm.get_task('memory-in')
        read.props.pointer = DATA.__array_interface__['data'][0]
        read.props.width = DATA.shape[1]
        read.props.height = DATA.shape[0]
        read.props.number = self.z_dim
        read.props.bitdepth = 32

        fft = pm.get_task('fft')
        fft.props.dimensions = 1

        filter = pm.get_task('filter')

        ifft = pm.get_task('ifft')
        ifft.props.dimensions = 1

        bp = pm.get_task('backproject')
        bp.props.axis_pos = DATA.shape[1] / 2

        vol_arr = np.zeros(self.volume_geometry.shape, dtype=np.float32)

        write = pm.get_task('memory-out')
        write.props.pointer = vol_arr.__array_interface__['data'][0]
        write.props.max_size = vol_arr.nbytes

        graph.connect_nodes(read, fft)
        graph.connect_nodes(fft, filter)
        graph.connect_nodes(filter, ifft)
        graph.connect_nodes(ifft, bp)
        graph.connect_nodes(bp, write)

        scheduler.run(graph)
        vol_arr = ImageData(vol_arr, deep_copy=False, geometry=self.volume_geometry.copy(), suppress_warning=True)

        return vol_arr