''' HP 12-C look-alike
    Designed for PythonWin running Tk/Tcl
    License:  Public Domain
    Author:   Raymond Hettinger
    Updates:  http://users.rcn.com/python/download/python.htm
'''

#  Revision In Use:  'File %n, Ver %v, Date %f'
version = 'File TWELVEC.PYW, Ver 35, Date 27-Mar-2002,3:20:02'

# TODO list:
# add scientific features:  trig, log, complex
# try to remove engine's dependencies on specific keys
# Put borders around displays, colors on keys
# try to generalize to work with non-stack calculators
# catch mathErrors like log(-1)
# figure out how to display UniCode through TCL
# idea to use State Pattern to handle digit entry
# implications of Inventors Paradox Pattern (generalized Display,Keyboard,CalcMachine)

#---------- Engine: do() called by Interface, calls updateDisplay, calls keyDefinitions

ZERO = 0.0
stack = []
prevSym = prevPrev = None
lastx = ZERO
deci = 1.0
mem = {}
finReg = [0,0,0,0,0]

def last( symbol ):
    if prevSym in ['Enter', 'CLx']:
        stack.pop()
    return lastx

def dig( symbol ):
    global deci
    if symbol in ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'] and prevSym in ['RCL', 'STO']:
        if prevSym == 'RCL':
            stack.append( mem[symbol] )
        elif prevSym == 'STO':
            mem[symbol] = stack[-1]
        return
    if prevSym in ['Enter', 'CLx']:
        stack[-1] = ZERO
    elif prevPrev in ['RCL', 'STO'] and prevSym in ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']:
        stack.append(ZERO)
    elif prevSym not in ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.', '\261', 'EEx']:
        stack.append(ZERO)
    if symbol == '.':
        deci = 0.1
        return
    if stack[-1] < 0.0:
        sign = -1.0
    else:
        sign = 1.0
    if deci < 1.0:
        stack[-1] += float(symbol) * deci * sign
        deci /= 10.0
    else:
        stack[-1] = stack[-1] * 10.0 + float(symbol) * sign

def do( symbol ):
    global prevSym, lastx, deci, prevPrev
    while( len(stack) < 6 ):
        stack[:0] = [ZERO]
    if function.has_key(symbol):
        if symbol not in ['LSTx', 'CHS', 'Enter', 'Swap', 'Roll', 'CLx']:
            lastx = stack[-1]
        itemsToRemove, commStr = function[symbol]
        (t, z, y, x) = stack[-4:]
        del stack[-itemsToRemove:]
        for command in commStr.split(';'):
            stack.append( eval(command)+0.0 )
        deci = 1.0
    else:
        dig(symbol)
    updateDisplay( stack )
    prevPrev = prevSym
    prevSym = symbol

def solve( objfun, arg, argref ):
    'Zero the objective function by applying Newtons method to arg tuple varying arg[argref]'
    x0 = arg[argref] + 1.0
    y0 = objfun( tuple( list(arg[:argref]) + [x0] + list(arg[argref+1:]) ) )
    x1 = arg[argref]
    for i in range(25):
        y1 = objfun( tuple( list(arg[:argref]) + [x1] + list(arg[argref+1:]) ) )
        if abs(y1-y0) < 1E-5:
            break
        x0, y0, x1 = x1, y1, x1-y1*(x1-x0)/(y1-y0)
    return x1

#---------- User Interface calls do(symbol) for each keypress and accepts calls to updateDisplay(stack) and launch()

from Tkinter import *
display = []

def activate( event ):
    do( event.widget['text'] )

def makeButton( win, symbol, row, col ):
    b = Button( win, bg='LightBlue', fg='Black', font='Lucinda 11 bold', cursor='crosshair', width=4, text=symbol )
    b.bind( '<Button-1>', activate )
    b.grid( row=row, col=col, sticky=W+E )

def addcommas( n ):
    'Converts float -234567890.1234 to string "-234,567,890.1234 "'
    l = list(str(n))
    limit = 4
    if '-' in l:
        limit = 5
    if '.' not in l:
        l.append( '.' )
    pos = l.index('.')
    while pos >= limit:
        pos -= 3
        l[pos:pos] = [',']
    return ''.join(l)

def updateDisplay( results ):
    offset = len(results) - len(display)
    assert offset >= 0, 'Result stack is to short to fully display'
    for i in range(len(display)):
        display[i].set( addcommas(results[i+offset]) )

def launch( layout, numDispLines=1 ):
    root= Tk()
    root.title('HP-12C')
    dispFrame = Frame( root )
    dispFrame.pack( side=TOP )
    for i in range( numDispLines ):
        display.append( StringVar(root) )
        Label( dispFrame, textvariable=display[-1], font='Arial 20 bold' ).grid(row=i,col=0)
    keyFrame = Frame( root )
    keyFrame.pack( side=TOP )
    for row in range(len(layout)):
        colkeys = layout[row].split(' ')
        for col in range(len(colkeys)):
            makeButton( keyFrame, colkeys[col], row, col )
    root.mainloop()

#--------- Resource Entries and Launch Command

from math import *

def fact(n):
    result = 1
    while n>1:
        result *= n
        n -= 1
    return result

def tvm( aTup ):
    'Objective function for Time Value of Money calculations.  Evaluates to zero for valid solutions'
    n, i, pv, pmt, fv = aTup
    i /= 100
    fv1 = (1.0+i)**n
    if abs(i) > 1E-10:
        return pv*fv1 + pmt*(fv1 - 1.0)/i + fv
    elif abs(i) > 1E-11:
        a1 = pv*fv1 + pmt*(fv1 - 1.0)/i + fv
        a2 = pv*fv1 + pmt*n*(1.0-(n+1.0)*i/2.0*(1.0-(n+2.0)*i/3.0)) + fv
        w = ( abs(i) - 1E-11 ) / ( 1E-10 - 1E-11 )
        return w * a1 + (1-w) * a2
    else:
        return pv*fv1 + pmt*n*(1.0-(n+1.0)*i/2.0*(1.0-(n+2.0)*i/3.0)) + fv

def fin(var, x):
    if prevSym in ['n', 'i', 'pv', 'pmt', 'fv']:
        x = solve( tvm, tuple(finReg), var )
    finReg[var] = x
    return x

function = { '+':   (2,'y+x'),
             '-':   (2,'y-x'),
             '\367':   (2,'y/x'),
             'x':   (2,'y*x'),
             '\261': (1,'-x'),
             'Enter':(1,'x;x'),
             'Swap':(2,'x;y'),
             'Roll':(2,'y'),
             'CLx': (1,'0.0'),
             'LSTx': (1,'x;last(x)'),
             '%':   (2,'y;x*y/100.0'),
             '%T':  (2,'y;x/y*100.0'),
             '%Chg':(2,'y;(x-y)/y*100.0'),
             '1/x': (1,'1/x'),
             'y^x': (2,'y**x'),
             'Sqrt':(1,'sqrt(x)'),
             'Ln':  (1,'log(x)'),
             'e^x': (1,'exp(x)'),
             'STO': (1,'x'),
             'RCL': (1,'x'),
             'n':   (1,'fin(0,x)'),
             'i':   (1,'fin(1,x)'),
             'pv':  (1,'fin(2,x)'),
             'pmt': (1,'fin(3,x)'),
             'fv':  (1,'fin(4,x)'),
             'n!':  (1,'fact(x)') }

layout = [ 'n i pv pmt fv', '1/x % LSTx 7 8 9 \367 STO', 'y^x %T CLx 4 5 6 x RCL', 'e^x %Chg Swap 1 2 3 - n!', 'Ln \261 Roll 0 . Enter + Sqrt' ]

launch(layout, numDispLines=1)