from Custom import CustomBase
import API
import hashlib

class SHA256 (CustomBase):
    stack = None
    
    def __init__(self, stack):
        self.stack = stack
    # __init__
    
    def help(self):
        msg =  "SHA1\n"
        msg += "----\n\n"
        msg += "Takes r0 from the stack\n\n"
        msg += "Calculates the SHA1 hash of r0\n\n"
        msg += "Pushes the result to r0"
        API.showPopup('Custom function', msg, font=('Courier',API.helpFontSize))
    # help

    def calculate(self):
        if self.stack.inputMode != 'TEXT':
            API.toast('This operation is only supported in TEXT mode')
            return
        if self.stack.finishEntry() == -1: 
            return # abort here because data in input line is invalid
        if self.stack.size() < 1:
            API.toast('This operation needs 1 argument')
            return
        r0 = self.stack.getRegister(0)
        self.stack.pop(1)
        m = hashlib.sha256()
        m.update(bytes(r0, 'utf-8'))
        self.stack.push(m.hexdigest())
    # calculate
    
# SHA256