package net.onrc.onos.core.datastore.hazelcast;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;

import java.nio.charset.StandardCharsets;
import java.util.Map;
import java.util.TreeMap;

import net.onrc.onos.core.datastore.IKVTable.IKVEntry;
import net.onrc.onos.core.datastore.ObjectDoesntExistException;
import net.onrc.onos.core.datastore.ObjectExistsException;
import net.onrc.onos.core.datastore.WrongVersionException;
import net.onrc.onos.core.datastore.hazelcast.HZTable.VersionedValue;
import net.onrc.onos.core.datastore.utils.ByteArrayComparator;

import org.junit.After;
import org.junit.Before;
import org.junit.Ignore;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TestName;

public class HZTableTest {
    @Rule
    public TestName name= new TestName();

    static final String TEST_TABLE_NAME = "TableForUnitTest";
    HZTable table;

    @Before
    public void setUp() throws Exception {
	table = (HZTable) HZClient.getClient().getTable(TEST_TABLE_NAME);
    }

    @After
    public void tearDown() throws Exception {
	HZClient.getClient().dropTable(table);
    }

    public void assertEntryInTable(final byte[] key, final byte[] value, final long version) {
	VersionedValue valueblob = table.getBackendMap().get(key);
	assertNotNull(valueblob);
	assertArrayEquals(value, valueblob.getValue());
	assertEquals(version, valueblob.getVersion());
    }

    public void assertKeyNotInTable(final byte[] key) {
	VersionedValue valueblob = table.getBackendMap().get(key);
	assertNull(valueblob);
    }

    @Test
    public void testGetInitialVersion() {
	final long version1 = HZTable.getInitialVersion();
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version1);

	final long version2 = HZTable.getInitialVersion();
	assertNotEquals(HZClient.VERSION_NONEXISTENT, version2);
	assertNotEquals(version1, version2);
    }

    @Test
    public void testGetNextVersion() {
	final long nextVersion = HZTable.getNextVersion(1);
	assertNotEquals(nextVersion, HZClient.VERSION_NONEXISTENT);
	assertNotEquals(nextVersion, 1);

	final long nextVersion1 = HZTable.getNextVersion(Long.MAX_VALUE);
	assertNotEquals(nextVersion1, HZClient.VERSION_NONEXISTENT);
	assertNotEquals(nextVersion1, Long.MAX_VALUE);

	final long nextVersion11 = HZTable.getNextVersion(HZClient.VERSION_NONEXISTENT-1);
	assertNotEquals(nextVersion11, HZClient.VERSION_NONEXISTENT);
	assertNotEquals(nextVersion11, HZClient.VERSION_NONEXISTENT-1);
    }

    @Ignore // nothing to test for now
    @Test
    public void testHZTable() {
	fail("Not yet implemented");
    }

    @Test
    public void testGetTableName() {
	assertEquals(TEST_TABLE_NAME, table.getTableName());
    }

    @Test
    public void testVERSION_NONEXISTENT() {
	assertEquals(HZClient.VERSION_NONEXISTENT, table.VERSION_NONEXISTENT());
    }

    @Test
    public void testGetTableId() {
	// for Hazelcast implementation IKVTableID is table itself
	assertEquals(table, table.getTableId());
    }

    @Test
    public void testCreate() throws ObjectExistsException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	final long version = table.create(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);

	assertEntryInTable(key, value, version);
    }

    @Test(expected = ObjectExistsException.class)
    public void testCreateConflict() throws ObjectExistsException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	final long version = table.create(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);

	assertEntryInTable(key, value, version);

	table.create(key, value);
	fail("Should have thrown exception");
    }

    @Test
    public void testForceCreate() {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	final long version = table.forceCreate(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);


	final long version1 = table.forceCreate(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version1);
	assertNotEquals(version, version1);
	assertEntryInTable(key, value, version1);
    }

    @Test
    public void testRead() throws ObjectDoesntExistException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	// put data to read
	final long version = table.forceCreate(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);

	// test body
	final IKVEntry readValue = table.read(key);
	assertArrayEquals(key, readValue.getKey());
	assertArrayEquals(value, readValue.getValue());
	assertEquals(version, readValue.getVersion());
    }


    @Test(expected = ObjectDoesntExistException.class)
    public void testReadNotExist() throws ObjectDoesntExistException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);

	table.read(key);
	fail("Should have thrown exception");
    }

    @Test
    public void testUpdateByteArrayByteArrayLongSuccess() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	// put data to update
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);

	final long version = table.update(key, value, oldVersion);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);
    }

    @Test(expected = ObjectDoesntExistException.class)
    public void testUpdateByteArrayByteArrayLongFailNoOldValue() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	final long oldVersion = 0xDEAD;

	final long version = table.update(key, value, oldVersion);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);
    }

    @Test(expected = WrongVersionException.class)
    public void testUpdateByteArrayByteArrayLongFailWrongVersion() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	// put data to update
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);
	// some one updates (from different thread/process in reality)
	table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);


	table.update(key, value, oldVersion);
	fail("Should have thrown exception");
    }

    @Test
    public void testUpdateByteArrayByteArraySuccess() throws ObjectDoesntExistException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	// put data to update
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);

	final long version = table.update(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);
    }

    @Test(expected = ObjectDoesntExistException.class)
    public void testUpdateByteArrayByteArrayFailNoOldValue() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	final long version = table.update(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);
	fail("Should have thrown exception");
    }

    @Test
    public void testUpdateByteArrayByteArraySuccessIgnoreVersion() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);
	final byte[] value = "SomeValue".getBytes(StandardCharsets.UTF_8);

	// put data to update
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);
	// someone updates (from different thread/process in reality)
	table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);


	final long version = table.update(key, value);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,version);
	assertEntryInTable(key, value, version);
    }

    @Test
    public void testDelete() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);

	// put data to delete
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);

	long version = table.delete(key, oldVersion);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEquals(oldVersion, version);
	assertKeyNotInTable(key);
    }

    @Test(expected = ObjectDoesntExistException.class)
    public void testDeleteFailNoEntry() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);

	final long oldVersion = 0xDEAD;

	try {
	    table.delete(key, oldVersion);
	} catch (ObjectDoesntExistException | WrongVersionException e) {
	    assertKeyNotInTable(key);
	    throw e;
	}
	fail("Should have thrown exception");
    }

    @Test(expected = WrongVersionException.class)
    public void testDeleteFailWrongVersion() throws ObjectDoesntExistException, WrongVersionException {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);

	// put data to delete
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);
	// someone updates (from different thread/process in reality)
	final long latestVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,latestVersion);

	try {
	    table.delete(key, oldVersion);
	} catch (ObjectDoesntExistException | WrongVersionException e) {
	    assertEntryInTable(key, oldValue, latestVersion);
	    throw e;
	}
	fail("Should have thrown exception");
    }


    @Test
    public void testForceDelete() {
	final byte[] key = name.getMethodName().getBytes(StandardCharsets.UTF_8);
	final byte[] oldValue = "OldValue".getBytes(StandardCharsets.UTF_8);

	// put data to delete
	final long oldVersion = table.forceCreate(key, oldValue);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEntryInTable(key, oldValue, oldVersion);

	long version = table.forceDelete(key);
	assertNotEquals(HZClient.VERSION_NONEXISTENT,oldVersion);
	assertEquals(oldVersion, version);
	assertKeyNotInTable(key);
    }

    @Test
    public void testGetAllEntries() {
	final int DATASETSIZE = 100;
	final Map<byte[], VersionedValue> testdata = new TreeMap<>(ByteArrayComparator.BYTEARRAY_COMPARATOR);
	for(int i = 0 ; i < DATASETSIZE ; ++i) {
	    final byte[] key = (name.getMethodName()+i).getBytes(StandardCharsets.UTF_8);
	    final byte[] value = ("Value"+i).getBytes(StandardCharsets.UTF_8);

	    // put data to delete
	    final long version = table.forceCreate(key, value);
	    assertNotEquals(HZClient.VERSION_NONEXISTENT, version);
	    assertEntryInTable(key, value, version);

	    testdata.put(key, new VersionedValue(value, version));
	}

	Iterable<IKVEntry> datastore = table.getAllEntries();
	for( IKVEntry entry : datastore ) {
	    VersionedValue expectedValue = testdata.get(entry.getKey());
	    assertNotNull(expectedValue);
	    assertArrayEquals(expectedValue.getValue(), entry.getValue());
	    assertEquals(expectedValue.getVersion(), entry.getVersion());

	    testdata.remove(entry.getKey());
	}

	assertTrue(testdata.isEmpty());
    }

    @Test
    public void testToString() {
	assertEquals("[HZTable " + TEST_TABLE_NAME + "]", table.toString());
    }

}