#!/usr/bin/python3

import sys
import re

if len(sys.argv) != 2:
    print("Usage: dptxt2gcode.py <input.dptxt>")
    sys.exit(1)

dptxt = open(sys.argv[1], 'r')

## Context
BRUSH_DIA = [1,1]
PEN_DOWN = False

_brush_dia_re = re.compile(r'size[hl]?=\d+')

## Print header boilerplate
print("""(BOILERPLATE)

G17 G40 G49 G80 G90 G94 G21
G54

(Scale values: pixels to mm)
#1 = 0.5 (X scale)
#2 = -#1  (Y scale)
#3 = [-#1/2] (Z scale)

#4 = 0   (X offset)
#5 = 0   (Y offset)

#6 = 2   (Safe Z height)

(BEGIN)
F600
G00 Z#6
""")

## Process recording
for line in dptxt:
    line = line.strip()
    if not line or line[0] == '#':
        continue

    if line.startswith('ctx '):
        # Update brush diameter
        sizes = _brush_dia_re.findall(line)
        for size in sizes:
            k,v = size.split('=')
            v = int(v)
            if k=='size':
                BRUSH_DIA = [v,v]
            elif k=='sizeh':
                BRUSH_DIA[0] = v
            else:
                BRUSH_DIA[1] = v

    elif line.startswith('move '):
        # Pen motion
        # We don't do anything with the context ID, but it
        # could be used for automatic tool changes.
        pointstr = line[line.find(' ', 5):]
        points = pointstr.split(';')
        for pstr in points:
            if pstr:
                p = pstr.strip().split(' ')
                if len(p) == 2:
                    x,y,z = float(p[0]), float(p[1]), 1.0
                else:
                    x,y,z = (float(v) for v in p)

                # convert pressure value [0..1] to pixel brush diameter pixel value
                z = BRUSH_DIA[1] + (BRUSH_DIA[0]-BRUSH_DIA[1]) * z

                xy_str = "X[#4 + #1*{:.4f}] Y[#5 + #2*{:.4f}]".format(x,y)
                z_str = "Z[#3*{:.4f}]".format(z)
                if PEN_DOWN:
                    print("G01", xy_str, z_str)

                else:
                    PEN_DOWN = True
                    print("G00", xy_str)
                    print("G01", z_str)


    elif line.startswith("penup "):
        # Pen up
        # Context ID is ignored. Only single-user recordings are supported.
        PEN_DOWN = False
        print("G00 Z#6")
        print("")

## Print footer boiler plate
print("""
M2
(END)
""")