# We owe a lot to MCell's implementation of the Margolus neighbourhood. Thanks Mirek!
#
# Tim Hutton <tim.hutton@gmail.com>

import os
import golly
from glife.ReadRuleTable import *
from glife.EmulateMargolus import *

# ask the user for the MCell string to convert (comma-separated works too)
s = golly.getstring(
'''Enter a specification string.

This can either be an MCell format Margolus string
or just a comma-separated list of the 16 case indices.

See: http://psoup.math.wisc.edu/mcell/rullex_marg.html
''',
"MS,D0;8;4;3;2;5;9;7;1;6;10;11;12;13;14;15","Enter Margolus specification") # defaults to BBM

# pull out the 16 numeric tokens that tell us what each partition becomes
becomes = map(int,s.replace('M',' ').replace('S',' ').replace(',',' ').replace('D',' ').replace(';',' ').split())

# write straight into the user's rules folder, so we can call setrule immediately
folder = golly.getdir('rules')

# construct a rule_name from next case indices
rule_name = 'Margolus-' + '-'.join(map(str,becomes))
# ask the user to confirm this name or suggest a more readable one (e.g. "BBM")
rule_name = golly.getstring("Enter a name for the rule:",rule_name,"Enter rule name")

# todo: detect slashes and tildes, tell user that can't change dir like that

# open the rule table file for writing
tablepath = folder + rule_name + '.table'
f = open(tablepath,'w')

# write the initial descriptors and some variables
f.write('# Emulation of Margolus neighbourhood for MCell string:\n# %s\n\n'%s)
f.write('# (see: http://psoup.math.wisc.edu/mcell/rullex_marg.html )\n')
f.write('#\n')
f.write('# Rule table produced by convert-MCell-string.py, which can\n')
f.write('# convert any MCell Margolus specification into a rule table.\n')
f.write('#\n')
f.write('n_states:2\nneighborhood:Margolus\nsymmetries:none\n\n')

# the 16 cases of the (two-state) Margolus partition are:
dot = (0,0,0,0),(1,0,0,0),(0,1,0,0),(1,1,0,0),(0,0,1,0),(1,0,1,0),(0,1,1,0),(1,1,1,0),\
      (0,0,0,1),(1,0,0,1),(0,1,0,1),(1,1,0,1),(0,0,1,1),(1,0,1,1),(0,1,1,1),(1,1,1,1)
# cell order: 1  2
#             3  4
# (see: http://psoup.math.wisc.edu/mcell/rullex_marg.html )

for i in range(16):
    if not i==becomes[i]:
        # (we can skip no-change transitions)
        f.write(','.join(map(str,dot[i]))+' : '+\
            ','.join(map(str,dot[becomes[i]]))+\
            '   # '+str(i)+' -> '+str(becomes[i])+'\n')
f.flush()
f.close()

# emulate the rule table with tree data in a .rule file
n_states, neighborhood, transitions = ReadRuleTable(tablepath)
golly.show("Building rule...")
rule_name = EmulateMargolus(neighborhood, n_states, transitions, tablepath)
os.remove(tablepath)

golly.new(rule_name+'-demo.rle')
golly.setalgo('RuleLoader')
golly.setrule(rule_name)
golly.show('Created '+rule_name+'.rule and selected that rule.')