import sqlite3 as sqlite
import unittest


@unittest.skipIf(sqlite.sqlite_version_info < (3, 6, 11), "Backup API not supported")
class BackupTests(unittest.TestCase):
 def setUp(self):
 cx = self.cx = sqlite.connect(":memory:")
 cx.execute('CREATE TABLE foo (key INTEGER)')
 cx.executemany('INSERT INTO foo (key) VALUES (?)', [(3,), (4,)])
 cx.commit()

 def tearDown(self):
 self.cx.close()

 def verify_backup(self, bckcx):
 result = bckcx.execute("SELECT key FROM foo ORDER BY key").fetchall()
 self.assertEqual(result[0][0], 3)
 self.assertEqual(result[1][0], 4)

 def test_bad_target_none(self):
 with self.assertRaises(TypeError):
 self.cx.backup(None)

 def test_bad_target_filename(self):
 with self.assertRaises(TypeError):
 self.cx.backup('some_file_name.db')

 def test_bad_target_same_connection(self):
 with self.assertRaises(ValueError):
 self.cx.backup(self.cx)

 def test_bad_target_closed_connection(self):
 bck = sqlite.connect(':memory:')
 bck.close()
 with self.assertRaises(sqlite.ProgrammingError):
 self.cx.backup(bck)

 def test_bad_target_in_transaction(self):
 bck = sqlite.connect(':memory:')
 bck.execute('CREATE TABLE bar (key INTEGER)')
 bck.executemany('INSERT INTO bar (key) VALUES (?)', [(3,), (4,)])
 with self.assertRaises(sqlite.OperationalError) as cm:
 self.cx.backup(bck)
 if sqlite.sqlite_version_info < (3, 8, 8):
 self.assertEqual(str(cm.exception), 'target is in transaction')

 def test_keyword_only_args(self):
 with self.assertRaises(TypeError):
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, 1)

 def test_simple(self):
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck)
 self.verify_backup(bck)

 def test_progress(self):
 journal = []

 def progress(status, remaining, total):
 journal.append(status)

 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, pages=1, progress=progress)
 self.verify_backup(bck)

 self.assertEqual(len(journal), 2)
 self.assertEqual(journal[0], sqlite.SQLITE_OK)
 self.assertEqual(journal[1], sqlite.SQLITE_DONE)

 def test_progress_all_pages_at_once_1(self):
 journal = []

 def progress(status, remaining, total):
 journal.append(remaining)

 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, progress=progress)
 self.verify_backup(bck)

 self.assertEqual(len(journal), 1)
 self.assertEqual(journal[0], 0)

 def test_progress_all_pages_at_once_2(self):
 journal = []

 def progress(status, remaining, total):
 journal.append(remaining)

 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, pages=-1, progress=progress)
 self.verify_backup(bck)

 self.assertEqual(len(journal), 1)
 self.assertEqual(journal[0], 0)

 def test_non_callable_progress(self):
 with self.assertRaises(TypeError) as cm:
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, pages=1, progress='bar')
 self.assertEqual(str(cm.exception), 'progress argument must be a callable')

 def test_modifying_progress(self):
 journal = []

 def progress(status, remaining, total):
 if not journal:
 self.cx.execute('INSERT INTO foo (key) VALUES (?)', (remaining+1000,))
 self.cx.commit()
 journal.append(remaining)

 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, pages=1, progress=progress)
 self.verify_backup(bck)

 result = bck.execute("SELECT key FROM foo"
 " WHERE key >= 1000"
 " ORDER BY key").fetchall()
 self.assertEqual(result[0][0], 1001)

 self.assertEqual(len(journal), 3)
 self.assertEqual(journal[0], 1)
 self.assertEqual(journal[1], 1)
 self.assertEqual(journal[2], 0)

 def test_failing_progress(self):
 def progress(status, remaining, total):
 raise SystemError('nearly out of space')

 with self.assertRaises(SystemError) as err:
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, progress=progress)
 self.assertEqual(str(err.exception), 'nearly out of space')

 def test_database_source_name(self):
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, name='main')
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, name='temp')
 with self.assertRaises(sqlite.OperationalError) as cm:
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, name='non-existing')
 self.assertIn(
 str(cm.exception),
 ['SQL logic error', 'SQL logic error or missing database']
 )

 self.cx.execute("ATTACH DATABASE ':memory:' AS attached_db")
 self.cx.execute('CREATE TABLE attached_db.foo (key INTEGER)')
 self.cx.executemany('INSERT INTO attached_db.foo (key) VALUES (?)', [(3,), (4,)])
 self.cx.commit()
 with sqlite.connect(':memory:') as bck:
 self.cx.backup(bck, name='attached_db')
 self.verify_backup(bck)


def suite():
 return unittest.makeSuite(BackupTests)

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