"""
    Services implemented: GMS/DEM/calls/slope
    POST: to get a slope map
"""
from monitorT.task import Task
from tools.layer import Layer, OutLayer
import os
import tempfile
# Fix gdal 2.40 and 3.3 integration problems
try:
    import gdal
except ModuleNotFoundError:
    from osgeo import gdal


class TaskCustom(Task):
    """
        clase interna itasker
    """
    CONTROL = True


def post(task, user=None, input_layer: Layer = None,
         output_layer: OutLayer = None, extra=False):
    """

        Servicio que devuelve un mapa de pendientes implementando las
        funcionalidades de GDAL

    Parameters
    ----------
    task
    user
    input_layer: Layer
        capa de entrada con protocolo FTP
    output_layer: OutLayer
        capa de salida
    extra: bool

    Returns
    -------

    """

    if not extra or extra == 'false' or extra == 'none':
        extra = ''
    task.set_progress(5)
    task.status_description = 'cargando capa'
    url_layer = input_layer.gdal_layer(with_vsi=True)
    src_ds = gdal.Open(url_layer)
    if src_ds is None:
        raise NameError("Unable to open INPUT.tif")
    # Generating temporal files
    task.set_progress(50)
    task.status_description = 'generando capa  raster ' \
                              'para almacenar la pendiente'
    tmp_directory = tempfile.mkdtemp(dir='tmp')
    slope_path = tempfile.NamedTemporaryFile(suffix='.tif',
                                             prefix='slope_result_',
                                             dir=tmp_directory).name

    command = "gdaldem slope {input} {output} {extra} -q".format(
        input=input_layer.gdal_layer(with_vsi=True), output=slope_path,
        extra=extra)
    os.system(command)

    task.set_progress(95)
    task.status_description = 'terminando'
    output_layer.attach_sources((slope_path, ))
    output_layer.residual_sources.append(tmp_directory)
    return output_layer