#Calcul.py

class Calcul():
 
    _current = 0
    _buffer = 0
    _show = 0
    _dec = False
    _decnum = 1
    _last_sign = None
    _input = True

    def press(self, widget, data):
        if self._last_sign == '-':
            self.__minus = -1

        else:
            self.__minus = 1

        if self._input != True:
            self._current = 0
            self._input = True
            __minus = 1

        if ~self._dec :
            self._current = float(self._current*10+self.__minus*data)

        else :
            self._current = float(self._current+self.__minus*data/self._decnum*10)
            self._decnum=+1

        self._show = self._current
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def clear(self, widget):
        self._current = 0
        self._buffer = 0
        self._show = 0
        self._dec = False
        self._decnum = 1
        self._last_sign = None
        self._input = True
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def back(self, widget):
        self._current = float(str(self._current)[:-1])
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def dot(self, widget):
        if self._decnum == 1:
            self._dec = True
    
    def plus(self, widget):
        if self._last_sign in ('+', '-', '*', '/', None):
            self.equals(widget)
        self._input = False
        self._last_sign = '+'
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def minus(self, widget):
        if self._last_sign in ('+', '-', '*', '/', None):
            self.equals(widget)
        self._input = False
        self._last_sign = '-'
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def multiply(self, widget):
        if self._last_sign in ('+', '-', '*', '/', None):
            self.equals(widget)
        self._input = False
        self._last_sign = '*'
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def divide(self, widget):
        if self._last_sign in ('+', '-', '*', '/', None):
            self.equals(widget)
        self._input = False
        self._last_sign = '/'
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)

    def equals(self, widget):
        if self._last_sign == None:
            self._buffer = self._current

        elif self._last_sign in ('+', '+='):
            self._buffer = self._buffer + self._current
            self._last_sign = '+='

        elif self._last_sign in ('-', '-='):
            self._buffer = self._buffer + self._current
            self._last_sign = '-='

        elif self._last_sign in ('*' '*='):
            self._buffer = self._buffer * self._current
            self._last_sign = '*='

        elif self._last_sign in ('/', '/='):
            self._buffer = self._buffer / self._current
            self._last_sign = '/='

        self._show = self._buffer
        self._input = False
        print("current:", self._current, "buffer:", self._buffer,\
                  "show:", self._show, "last sign:", self._last_sign)