# *****************************************************************************
#
# 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 2 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, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# Module authors:
#   Markus Zolliker <markus.zolliker@psi.ch>
#
# *****************************************************************************
"""helper devices for lab experiments"""

import time

from nicos.core import Override, Param, Measurable
from nicos.core.params import Value


class Timestamp(Measurable):
    """to be used as a 'detector' in lab experiments

    just waiting the preset time
    """
    parameter_overrides = {
        'unit': Override(default='sec', mandatory=False),
    }
    parameters = {
        'show': Param('show timestamp in data file', type=bool,
                      settable=True, default=True, mandatory=False),
    }

    _preset = 0
    _time_used = 0
    _start = 0

    def _getCache(self):
        """no cache needed"""
        self._cache = None

    def doRead(self, maxage=0):
        return time.time()

    def doStatus(self, maxage=0):
        return 100, ''

    def doSetPreset(self, t=0, **preset):
        self._start = 0
        self._preset = t
        self._value = 0

    def doStart(self):
        self._start = time.time()

    def doPause(self):
        self._time_used = time.time() - self._start
        return True

    def doResume(self):
        self._start = time.time() - self._time_used

    def doFinish(self):
        pass

    def doStop(self):
        pass

    def doIsCompleted(self):
        return time.time() > self._start + self._preset

    def valueInfo(self):
        if self.show:
            return Measurable.valueInfo(self)
        return ()


class Det(Measurable):
    """wrap a Readable into a Detector

    just for placing the result in a scan file in the detector part
    """
    temporary = True

    def __init__(self, dev):
        self._dev = dev
        Measurable.__init__(self, str(dev), unit=dev.unit, fmtstr=dev.fmtstr)

    def _getCache(self):
        """no cache needed"""
        self._cache = None

    def doRead(self, maxage=0):
        return self._dev.doRead(maxage)

    def doStatus(self, maxage=0):
        return self._dev.doStatus(maxage)

    def doSetPreset(self, t=5, **preset):
        self._start = 0
        self._preset = t

    def doStart(self):
        self._start = time.time()

    def doFinish(self):
        pass

    def doStop(self):
        self._start = 0

    def doIsCompleted(self):
        return time.time() > self._start + self._preset

    def valueInfo(self):
        return Value(self.name, unit=self.unit, fmtstr=self.fmtstr),