# -*- mode: python; coding: utf-8 -*-
# Copyright (C) 2018 Laboratoire de Recherche et
# Développement de l'Epita
#
# This file is part of Spot, a model checking library.
#
# Spot is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# Spot is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
# or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
# License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import spot

def incl(a,b):
    return not b.intersects(spot.dualize(spot.tgba_determinize(a)))
def equiv(a,b):
    return incl(a,b) and incl(b,a)

def do_split(f, in_list):
    aut = spot.translate(f)
    inputs = spot.buddy.bddtrue
    for a in in_list:
        inputs &= spot.buddy.bdd_ithvar(aut.get_dict().varnum(spot.formula(a)))
    s = spot.split_2step(aut, inputs)
    return aut,s

aut, s = do_split('(FG !a) <-> (GF b)', ['a'])
assert equiv(aut, spot.unsplit_2step(s))

aut, s = do_split('GFa && GFb', ['a'])
assert equiv(aut, spot.unsplit_2step(s))
assert s.to_str() == """HOA: v1
States: 3
Start: 0
AP: 2 "a" "b"
acc-name: generalized-Buchi 2
Acceptance: 2 Inf(0)&Inf(1)
properties: trans-labels explicit-labels trans-acc complete
properties: deterministic
--BODY--
State: 0
[0] 1
[!0] 2
State: 1
[!1] 0 {0}
[1] 0 {0 1}
State: 2
[!1] 0
[1] 0 {1}
--END--"""

aut, s = do_split('! ((G (req -> (F ack))) && (G (go -> (F grant))))', ['go',
    'req'])
assert equiv(aut, spot.unsplit_2step(s))
# FIXME s.to_str() is NOT the same on Debian stable and on Debian unstable
#       we should investigate this
#assert s.to_str() == """HOA: v1
#States: 9
#Start: 0
#AP: 4 "ack" "req" "go" "grant"
#acc-name: Buchi
#Acceptance: 1 Inf(0)
#properties: trans-labels explicit-labels state-acc
#--BODY--
#State: 0
#[1&!2] 3
#[!1&!2] 4
#[1&2] 5
#[!1&2] 6
#State: 1
#[t] 7
#State: 2
#[t] 8
#State: 3
#[t] 0
#[!0] 1
#State: 4
#[t] 0
#State: 5
#[t] 0
#[!0] 1
#[!3] 2
#State: 6
#[t] 0
#[!3] 2
#State: 7 {0}
#[!0] 1
#State: 8 {0}
#[!3] 2
#--END--"""

aut, s = do_split('((G (((! g_0) || (! g_1)) && ((r_0 && (X r_1)) -> (F (g_0 \
    && g_1))))) && (G (r_0 -> F g_0))) && (G (r_1 -> F g_1))', ['r_0', 'r_1'])
assert equiv(aut, spot.unsplit_2step(s))