"""Focused tactical and protocol regressions; run directly with Python 3."""
import contextlib
import io
from pathlib import Path
import sys
import unittest

sys.path.insert(0, str(Path(__file__).resolve().parent))
import bot


class BrainTests(unittest.TestCase):
    def setUp(self):
        bot.N = 15
        bot.board.clear()

    def stones(self, points, colour=1):
        bot.board.update((p, colour) for p in points)

    def test_first_move(self):
        self.assertEqual(bot.move(), (7, 7))

    def test_exact_five_in_every_direction(self):
        for dx, dy in bot.DIRECTIONS:
            bot.board.clear()
            self.stones([(7 + i * dx, 7 + i * dy) for i in (-2, -1, 1, 2)])
            self.assertTrue(bot.evaluate((7, 7), 1)[0])
            self.assertEqual(bot.move(), (7, 7))

    def test_overline_is_not_win(self):
        self.stones([(x, 7) for x in (3, 4, 5, 7, 8)])
        self.assertFalse(bot.evaluate((6, 7), 1)[0])

    def test_win_before_block(self):
        self.stones([(x, 4) for x in range(4)], 1)
        self.stones([(x, 10) for x in range(4)], 2)
        self.assertEqual(bot.move(), (4, 4))

    def test_block_opponent_broken_five(self):
        self.stones([(x, 7) for x in (3, 4, 6, 7)], 2)
        self.assertEqual(bot.move(), (5, 7))

    def test_open_line_beats_closed(self):
        self.stones([(6, 7), (8, 7)])
        open_score = bot.evaluate((7, 7), 1)[1]
        self.stones([(5, 7)], 2)
        self.assertGreater(open_score, bot.evaluate((7, 7), 1)[1])

    def test_gap_four_has_winning_completion(self):
        self.stones([(5, 7), (8, 7), (9, 7)])
        _, offsets, _ = bot.line_value(bot.line_at(6, 7, 1, 1, 0))
        self.assertIn(1, offsets)

    def test_open_four_has_two_winning_points(self):
        self.stones([(5, 7), (6, 7), (8, 7)])
        _, offsets, _ = bot.line_value(bot.line_at(7, 7, 1, 1, 0))
        self.assertEqual(offsets, {-3, 2})

    def test_edge_is_closed(self):
        self.stones([(0, 7), (1, 7)])
        _, offsets, _ = bot.line_value(bot.line_at(2, 7, 1, 1, 0))
        self.assertFalse(offsets)
        self.assertNotEqual(bot.line_at(2, 7, 1, 1, 0)[0], '.')

    def test_snapshot_restart_and_blocked_cells(self):
        commands = 'START 15\nBEGIN\nBOARD\n0,0,3\n1,0,2\nDONE\nRESTART\nBEGIN\nEND\n'
        out = io.StringIO()
        old_stdin = sys.stdin
        try:
            sys.stdin = io.StringIO(commands)
            with contextlib.redirect_stdout(out):
                bot.main()
        finally:
            sys.stdin = old_stdin
        lines = out.getvalue().splitlines()
        self.assertEqual(lines[0:2], ['OK', '7,7'])
        self.assertNotIn(lines[2], ['0,0', '1,0'])
        self.assertEqual(lines[3:], ['OK', '7,7'])
        self.assertEqual(bot.board, {(7, 7): 1})

    def test_board_replaces_previous_position(self):
        self.stones([(14, 14)], 2)
        old_stdin = sys.stdin
        try:
            sys.stdin = io.StringIO('BOARD\n0,0,3\n1,0,2\nDONE\nEND\n')
            with contextlib.redirect_stdout(io.StringIO()):
                bot.main()
        finally:
            sys.stdin = old_stdin
        self.assertNotIn((14, 14), bot.board)
        self.assertEqual(bot.board[(0, 0)], 3)
        self.assertEqual(bot.board[(1, 0)], 2)
        self.assertEqual(len(bot.board), 3)


if __name__ == '__main__':
    unittest.main()