#!/usr/bin/env python

import argparse
import os
import re
import sys
from decimal import Decimal as d


class GCodePosition(object):

    def __init__(self, lower, upper, shift):
        self.pos = [d(0), d(0), d(0)]
        self.lower = lower
        self.upper = upper
        self.shift = shift

    def is_inside(self):
        for i in range(len(self.pos)):
            if not ((self.lower[i] is None or (self.lower[i] <= self.pos[i])) and \
                    (self.upper[i] is None or (self.upper[i] >= self.pos[i]))):
                return False
        return True


    def get_shifted_line(self, line):
        """ parse the line, update current position replace shifted values
        """
        axis_pattern = r"\b([XYZ][\+\-0-9\.]+)\b"
        result = []
        # first: update the x/y/z position (make sure that we are in the box)
        for token in re.findall(axis_pattern, line, flags=re.I):
            for i, axis in enumerate("XYZ"):
                if token.upper().startswith(axis):
                    self.pos[i] = d(token[1:])
        # second: replace values
        if self.is_inside():
            def replace_value(match):
                token = match.group(0).upper()
                for i, axis in enumerate("XYZ"):
                    if token.startswith(axis):
                        value = d(token[1:])
                        return token[0] + str(value + self.shift[i])
                return token
            return re.sub(axis_pattern, replace_value, line, re.I)
        else:
            return line


if __name__ == "__main__":
    parser = argparse.ArgumentParser(description="Shift parts of gcode")
    parser.add_argument('--minx', dest="minx", type=d)
    parser.add_argument('--maxx', dest="maxx", type=d)
    parser.add_argument('--miny', dest="miny", type=d)
    parser.add_argument('--maxy', dest="maxy", type=d)
    parser.add_argument('--minz', dest="minz", type=d)
    parser.add_argument('--maxz', dest="maxz", type=d)
    parser.add_argument('--shiftx', dest="shiftx", type=d, default=d(0))
    parser.add_argument('--shifty', dest="shifty", type=d, default=d(0))
    parser.add_argument('--shiftz', dest="shiftz", type=d, default=d(0))
    infile = sys.stdin
    outfile = sys.stdout
    options = parser.parse_args()
    shifter = GCodePosition((options.minx, options.miny, options.minz),
            (options.maxx, options.maxy, options.maxz),
            (options.shiftx, options.shifty, options.shiftz))
    for line in infile.readlines():
        outfile.write(shifter.get_shifted_line(line))