#WIP !!!
#File could be updated regularly on my website without warning !

import win32com
xsi = win32com.client.Dispatch( 'XSI.Application' ).Application

class Expression:
    '''
    Feel free to add more XSI expressions to the Expression class !
    Then you can send the file to guillaume.laforge.3d@gmail.com
    
    - Those methodes are the same than XSI expressions :
    ctr_dist , abs, pow, at_frame, exp.

    - Those methodes are a combination of several XSI expressions :
    clamp(XSI parameter, mini=1, maxi=0)
    fit(XSI parameter, oldmin, oldmax, newmin=0, newmax=1)
      
    You can use the add, sub, mul and div methods to insert an operator (+ ,- ,* ,/) between two xsi parameter objects in order to get a valid xsi expression.
    
    examples :

    myExpression = Expression(xsi parameter) -> Create an Expression object with the xsi parameter.

    myExpression.Value -> To get the fullName. Ex : null.Kinematics.Local.posx

    myExpression.add(xsi parameter 2) -> insert "+" between the two parameters like this :
                                   null.Kinematics.Local.posx + null.Kinematics.Local.posy

    myExpression.show() -> print the Expression value from a Python Shell.
    myExpression.xsiShow() -> print the Expression value from the xsi script log.

    myExpression.text(a string object, 'end') -> insert a string after the Expression value.
                                         Default Value : before the Expression value

    myExpression.par() -> enclose the expression between parentheses : ( null.Kinematics.Local.posx + null.Kinematics.Local.posy )
    
    '''

    def __init__(self, parm=''):
        self.Value = str(parm)

    def set(self, parm):
        self.Value = str(parm)
    
    #Math Operations
    def add(self, *args):
        for arg in enumerate(args):
            self.Value+=' + '+str(arg[1])

    def sub(self, *args):
        for arg in enumerate(args):
            self.Value+=' - '+str(arg[1])
            
    def mul(self, *args):
        for arg in enumerate(args):
            self.Value+=' * '+str(arg[1])

    def div(self, *args):
        for arg in enumerate(args):
            self.Value+=' / '+str(arg[1])

    def par(self):
        self.Value = ' ( '+self.Value+' ) '


    #Some 'standard' XSI expressions
    def ctr_dist(self, obj1, obj2):
        self.Value = 'ctr_dist( '+str(obj1)+'. , '+str(obj2)+'. )'

    def abs(self):
        self.Value = 'abs('+self.Value+')'

    def at_frame( self, frame, parm):
        self.Value = 'at_frame( Fc - '+str(frame)+','+str(parm)+')'

    def pow( self, parm1 , power=2 ):
            self.Value = 'pow( '+str(parm1)+' , '+str(power)+' )'

    def exp( self, parm1 ):
            self.Value = 'exp( '+str(parm1)+' )'

    def cond( self, cond , true_expr , false_expr ):
            self.Value = 'cond( '+str(cond)+' , '+str(true_expr)+' , '+str(false_expr)+' )'

    #From mixing standard XSI expression
    def clamp(self, parm, mini=1, maxi=0):
        self.Value = 'MIN( MAX( '+str(parm)+', '+str(mini)+' ), '+str(maxi)+' )'

    def fit(self, parm, oldmin, oldmax, newmin=0, newmax=1):
        self.Value = 'cond( '+str(parm)+'<0, ('+str(parm)+'/'+str(oldmin)+')*'+str(newin)+', ('+str(parm)+'/'+str(oldmax)+')*'+str(newmax)+' )'
       
    #Utils
    def show(self):
        print self.Value

    def text(self, text='', pos='start'):
        if pos =='start':
            self.Value= text+self.Value
        else:
            self.Value = self.Value+text            

    #To Log the Expression object value
    def xsiShow(self):
        xsi.LogMessage(self.Value)
    #A quick way to see the doc from XSI
    def xsiDoc(self):
        xsi.LogMessage(self.__doc__)