#!/usr/bin/python3
# -*- mode: python; coding: utf-8 -*-
# Copyright (C) 2017, 2021, 2022 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
from unittest import TestCase
tc = TestCase()

a = spot.translate('(Ga -> Gb) W c')

try:
    si = spot.scc_info(a, 10)
    exit(2)
except RuntimeError as e:
    tc.assertIn("initial state does not exist", str(e))

si = spot.scc_info(a)
n = si.scc_count()
tc.assertEqual(n, 4)

acc = 0
rej = 0
triv = 0
for i in range(n):
    acc += si.is_accepting_scc(i)
    rej += si.is_rejecting_scc(i)
    triv += si.is_trivial(i)
tc.assertEqual(acc, 3)
tc.assertEqual(rej, 1)
tc.assertEqual(triv, 0)

for scc in si:
    acc -= scc.is_accepting()
    rej -= scc.is_rejecting()
    triv -= scc.is_trivial()
tc.assertEqual(acc, 0)
tc.assertEqual(rej, 0)
tc.assertEqual(triv, 0)

l0 = si.states_of(0)
l1 = si.states_of(1)
l2 = si.states_of(2)
l3 = si.states_of(3)
l = sorted(list(l0) + list(l1) + list(l2) + list(l3))
tc.assertEqual(l, [0, 1, 2, 3, 4])

i = si.initial()
todo = [i]
seen = {i}
trans = []
transi = []
while todo:
    e = todo.pop()
    for t in si.edges_of(e):
        trans.append((t.src, t.dst))
    for t in si.inner_edges_of(e):
        transi.append((t.src, t.dst, a.edge_number(t)))
    for s in si.succ(e):
        if s not in seen:
            seen.add(s)
            todo.append(s)
tc.assertEqual(seen, {0, 1, 2, 3})
tc.assertEqual(trans, [(0, 0), (0, 1), (0, 2), (0, 3),
                       (2, 0), (2, 1), (2, 2), (2, 4),
                       (3, 3), (4, 1), (4, 4), (1, 1)])
tc.assertEqual(transi, [(0, 0, 1), (0, 2, 3), (2, 0, 6),
                        (2, 2, 8), (3, 3, 10), (4, 4, 12), (1, 1, 5)])

tc.assertFalse(spot.is_weak_automaton(a, si))


a = spot.automaton("""
HOA: v1
States: 4
Start: 0
AP: 1 "a"
Acceptance: 2 Inf(0)&Fin(1)
--BODY--
State: 0
[t] 0 {1}
[t] 1 {0}
State: 1
[t] 1 {1}
[t] 0 {1}
[t] 2
State: 2
[t] 2 {1}
[t] 3 {0}
State: 3
[t] 3 {1}
[t] 2
--END--
""")
si = spot.scc_info(a)
si.determine_unknown_acceptance()
tc.assertEqual(si.scc_count(), 2)
tc.assertTrue(si.is_accepting_scc(0))
tc.assertFalse(si.is_rejecting_scc(0))
tc.assertTrue(si.is_rejecting_scc(1))
tc.assertFalse(si.is_accepting_scc(1))