def onAutoIndentTriggered(self):
        """Indent current line or selected lines
        """
        cursor = self._qpart.textCursor()

        startBlock = self._qpart.document().findBlock(cursor.selectionStart())
        endBlock = self._qpart.document().findBlock(cursor.selectionEnd())

        if startBlock != endBlock:  # indent multiply lines
            stopBlock = endBlock.next()

            block = startBlock

            with self._qpart:
                while block != stopBlock:
                    self.autoIndentBlock(block, '')
                    block = block.next()
        else:  # indent 1 line
            self.autoIndentBlock(startBlock, '')
def setSaSS(self, lenp2, lenp3, lenp1):
        self.lenp2 = lenp2
        self.lenp3 = lenp3
        self.lenp1 = lenp1
        if(self.lenp1 > (self.lenp2 + self.lenp3)):
        #<CAB 夾角為 180 度, 三點共線且 A 介於 BC 之間
            ret = math.pi
        else :
            # <CAB 夾角為 0, 三點共線且 A 不在 BC 之間
            if((self.lenp1 < (self.lenp2 - self.lenp3)) or (self.lenp1 < (self.lenp3 - self.lenp2))):
                ret = 0.0
            else :
            # 透過餘絃定理求出夾角 <CAB 
                ret = math.acos(((self.lenp2 * self.lenp2 + self.lenp3 * self.lenp3) - self.lenp1 * self.lenp1) / (2 * self.lenp2 * self.lenp3))
        return ret