from qolab.hardware.basic import BasicInstrument
from qolab.hardware.rf_generator import RFGenerator
import serial
import re


class QOL_LMX2487(RFGenerator):
    """
    QOL lab made RF generator based on TI LMX2487 chip.
    The communication with RF generator is done via nodeMCU controlling esp2866 chip.
    """
    def __init__(self, *args,  port='/dev/ttyUSB0', speed=115200, timeout=1, setToDefaults=True, **kwds):
        super().__init__(*args, **kwds)
        self.config['Device model'] = 'QOL made RF generator based on TI LMX2487 chip'
        self.port = port
        self.speed = speed
        self.timeout = timeout
        self.connection = serial.Serial( self.port, self.speed, timeout=self.timeout)
        self.log = []
        self.logCapacity = 10
        self._FreqFixed = None
        self.hopeFreeFreqJump = 100e3 # we break laser lock if Freq change is larger
        self.hopeFree = True
        if setToDefaults:
            self.sendSerialCmd("set_lmx2487_board_to_default_state()")

    def add2log(self, text):
        self.log.append(text)
        while len(self.log) > self.logCapacity:
            self.log.pop(0)

    def log2str(self, interval=None):
        strOut = ""
        for e in self.log:
            strOut += e
        return strOut

    def sendSerialCmd(self, cmd):
        self.connection.write(bytes(cmd+'\r','ascii'))
        if "3.4" == serial.__version__:
            # older version style
            resp = self.connection.read_until(terminator=b'> ')
        else:
            # new style after 20180616
            resp = self.connection.read_until(expected=b'> ')
        resp = resp.decode('utf-8')
        self.add2log(resp)
        return resp

    @BasicInstrument.tsdb_append
    def setFreqFixed(self,freq):
        """ 
        Will do incremental hope free tuning to desired frequency,
        if self.hopeFree is True.
        RF generator itself is fine, but our laser looses lock without it.
        """

        finished = False
        while not finished:
            frNow = self.getFreqFixed()
            dF = freq-frNow
            if dF >= 0:
                dFSign = 1
            else:
                dFSign = -1
            dF = abs(dF)
            if dF <= self.hopeFreeFreqJump or not self.hopeFree:
                fr = freq
                finished = True
            else:
                fr = frNow + dFSign * self.hopeFreeFreqJump
            self._FreqFixed = fr
            cmd_str=f'setFreq({fr:.2f})'
            self.sendSerialCmd(cmd_str)

    @BasicInstrument.tsdb_append
    def getFreqFixed(self):
        # talking to hardware is slow, so we use cached value if we can
        if self._FreqFixed is None:
            resp = self.sendSerialCmd('getFreq()')
            m = re.search('[0-9.]+', resp)
            if m is not None:
                self._FreqFixed = float(m.group())
        return self._FreqFixed


if __name__ == '__main__': 
    import platform
    if platform.system() == 'Linux':
        rfgen=QOL_LMX2487(port='/dev/ttyUSB0', speed=115200, timeout=1)
    else:
        rfgen=QOL_LMX2487(port='COM4', speed=115200, timeout=1)
    print("testing")
    print('------ Header start -------------')
    print(str.join('\n', rfgen.getHeader()))
    print('------ Header ends  -------------')