# This file is part of meas_base.
#
# Developed for the LSST Data Management System.
# This product includes software developed by the LSST Project
# (https://www.lsst.org).
# See the COPYRIGHT file at the top-level directory of this distribution
# for details of code ownership.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

from contextlib import contextmanager
import unittest

import lsst.geom
import lsst.daf.base
import lsst.meas.base
import lsst.utils.tests

from lsst.meas.base.tests import (AlgorithmTestCase, CentroidTransformTestCase,
                                  SingleFramePluginTransformSetupHelper, ForcedPluginTransformSetupHelper)


@contextmanager
def onlyLogFatal(log):
    """For the duration of this context, only log ``FATAL`` errors.

    This is convenient when testing algorithms under failure conditions: we
    want to be able to check that they have set appropriate flags without
    spewing alarming & confusing error messages to the console.
    """
    oldLevel = log.getLevel()
    log.setLevel(log.FATAL)
    try:
        yield
    finally:
        log.setLevel(oldLevel)


class SingleFramePeakCentroidTestCase(AlgorithmTestCase, lsst.utils.tests.TestCase):

    def setUp(self):
        self.center = lsst.geom.Point2D(50.1, 49.8)
        self.bbox = lsst.geom.Box2I(lsst.geom.Point2I(-20, -30),
                                    lsst.geom.Extent2I(140, 160))
        self.dataset = lsst.meas.base.tests.TestDataset(self.bbox)
        self.dataset.addSource(1000000.0, self.center)
        self.task = self.makeSingleFrameMeasurementTask("base_PeakCentroid")
        self.exposure, self.catalog = self.dataset.realize(10.0, self.task.schema, randomSeed=0)

    def tearDown(self):
        del self.center
        del self.bbox
        del self.dataset
        del self.task
        del self.exposure
        del self.catalog

    def testSingleFramePlugin(self):
        """Check that we recover the correct location of the centroid.
        """
        self.task.run(self.catalog, self.exposure)
        x = self.catalog[0].get("base_PeakCentroid_x")
        y = self.catalog[0].get("base_PeakCentroid_y")
        self.assertFalse(self.catalog[0].get("base_PeakCentroid_flag"))
        self.assertFloatsAlmostEqual(x, self.center.getX(), atol=None, rtol=.02)
        self.assertFloatsAlmostEqual(y, self.center.getY(), atol=None, rtol=.02)

    def testFlags(self):
        """Test that a flag is set when centroid measurement is impossible.

        Notes
        -----
        In this case, it is impossible to measure the centroid because we
        remove the peaks from the `~lsst.afw.table.SourceRecord`.
        """
        self.catalog[0].getFootprint().getPeaks().clear()
        # The decorator suppresses alarming but expected errors on the console.
        with onlyLogFatal(self.task.log):
            self.task.run(self.catalog, self.exposure)
        self.assertTrue(self.catalog[0].get("base_PeakCentroid_flag"))


class SingleFramePeakCentroidTransformTestCase(CentroidTransformTestCase,
                                               SingleFramePluginTransformSetupHelper,
                                               lsst.utils.tests.TestCase):

    class SingleFramePeakCentroidPluginFactory:
        """Supply an empty ``PropertyList`` to `XingleFramePeakCentroidPlugin`.

        This is a helper class to make testing more convenient.
        """

        def __call__(self, control, name, inputSchema):
            return lsst.meas.base.SingleFramePeakCentroidPlugin(control, name, inputSchema,
                                                                lsst.daf.base.PropertyList())
    controlClass = lsst.meas.base.SingleFramePeakCentroidConfig
    algorithmClass = SingleFramePeakCentroidPluginFactory()
    transformClass = lsst.meas.base.SimpleCentroidTransform
    flagNames = ()
    singleFramePlugins = ("base_PeakCentroid",)


class ForcedPeakCentroidTransformTestCase(CentroidTransformTestCase,
                                          ForcedPluginTransformSetupHelper,
                                          lsst.utils.tests.TestCase):
    controlClass = lsst.meas.base.ForcedPeakCentroidConfig
    algorithmClass = lsst.meas.base.ForcedPeakCentroidPlugin
    transformClass = lsst.meas.base.SimpleCentroidTransform
    flagNames = ()
    forcedPlugins = ("base_PeakCentroid",)


class TestMemory(lsst.utils.tests.MemoryTestCase):
    pass


def setup_module(module):
    lsst.utils.tests.init()


if __name__ == "__main__":
    lsst.utils.tests.init()
    unittest.main()