package edu.uci.ics.asterix.runtime.aggregates.serializable.std;

import java.io.DataOutput;
import java.io.IOException;

import edu.uci.ics.asterix.common.config.GlobalConfig;
import edu.uci.ics.asterix.common.functions.FunctionConstants;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.ADoubleSerializerDeserializer;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.AFloatSerializerDeserializer;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.AInt16SerializerDeserializer;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.AInt32SerializerDeserializer;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.AInt64SerializerDeserializer;
import edu.uci.ics.asterix.dataflow.data.nontagged.serde.AInt8SerializerDeserializer;
import edu.uci.ics.asterix.formats.nontagged.AqlSerializerDeserializerProvider;
import edu.uci.ics.asterix.om.base.AMutableDouble;
import edu.uci.ics.asterix.om.base.AMutableFloat;
import edu.uci.ics.asterix.om.base.AMutableInt16;
import edu.uci.ics.asterix.om.base.AMutableInt32;
import edu.uci.ics.asterix.om.base.AMutableInt64;
import edu.uci.ics.asterix.om.base.AMutableInt8;
import edu.uci.ics.asterix.om.base.ANull;
import edu.uci.ics.asterix.om.types.ATypeTag;
import edu.uci.ics.asterix.om.types.BuiltinType;
import edu.uci.ics.asterix.om.types.EnumDeserializer;
import edu.uci.ics.asterix.runtime.aggregates.base.AbstractSerializableAggregateFunctionDynamicDescriptor;
import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
import edu.uci.ics.hyracks.algebricks.common.exceptions.NotImplementedException;
import edu.uci.ics.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
import edu.uci.ics.hyracks.algebricks.runtime.base.IEvaluator;
import edu.uci.ics.hyracks.algebricks.runtime.base.IEvaluatorFactory;
import edu.uci.ics.hyracks.algebricks.runtime.base.ISerializableAggregateFunction;
import edu.uci.ics.hyracks.algebricks.runtime.base.ISerializableAggregateFunctionFactory;
import edu.uci.ics.hyracks.api.dataflow.value.ISerializerDeserializer;
import edu.uci.ics.hyracks.dataflow.common.data.accessors.ArrayBackedValueStorage;
import edu.uci.ics.hyracks.dataflow.common.data.accessors.IFrameTupleReference;

public class SerializableSumAggregateDescriptor extends AbstractSerializableAggregateFunctionDynamicDescriptor {

    private static final long serialVersionUID = 1L;
    private final static FunctionIdentifier FID = new FunctionIdentifier(FunctionConstants.ASTERIX_NS, "sum-serial", 1,
            true);

    @Override
    public FunctionIdentifier getIdentifier() {
        return FID;
    }

    @Override
    public ISerializableAggregateFunctionFactory createAggregateFunctionFactory(final IEvaluatorFactory[] args)
            throws AlgebricksException {
        return new ISerializableAggregateFunctionFactory() {
            private static final long serialVersionUID = 1L;

            @Override
            public ISerializableAggregateFunction createAggregateFunction() throws AlgebricksException {

                return new ISerializableAggregateFunction() {

                    private ArrayBackedValueStorage inputVal = new ArrayBackedValueStorage();
                    private IEvaluator eval = args[0].createEvaluator(inputVal);
                    private AMutableDouble aDouble = new AMutableDouble(0);
                    private AMutableFloat aFloat = new AMutableFloat(0);
                    private AMutableInt64 aInt64 = new AMutableInt64(0);
                    private AMutableInt32 aInt32 = new AMutableInt32(0);
                    private AMutableInt16 aInt16 = new AMutableInt16((short) 0);
                    private AMutableInt8 aInt8 = new AMutableInt8((byte) 0);
                    @SuppressWarnings("unchecked")
                    private ISerializerDeserializer serde;

                    @Override
                    public void init(DataOutput state) throws AlgebricksException {
                        try {
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeBoolean(false);
                            state.writeDouble(0.0);
                        } catch (IOException e) {
                            throw new AlgebricksException(e);
                        }
                    }

                    @Override
                    public void step(IFrameTupleReference tuple, byte[] state, int start, int len)
                            throws AlgebricksException {
                        int pos = start;
                        boolean metInt8s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt16s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt32s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt64s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metFloats = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metDoubles = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metNull = BufferSerDeUtil.getBoolean(state, pos++);
                        double sum = BufferSerDeUtil.getDouble(state, pos);

                        inputVal.reset();
                        eval.evaluate(tuple);
                        if (inputVal.getLength() > 0) {
                            ATypeTag typeTag = EnumDeserializer.ATYPETAGDESERIALIZER
                                    .deserialize(inputVal.getBytes()[0]);
                            switch (typeTag) {
                                case INT8: {
                                    metInt8s = true;
                                    byte val = AInt8SerializerDeserializer.getByte(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case INT16: {
                                    metInt16s = true;
                                    short val = AInt16SerializerDeserializer.getShort(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case INT32: {
                                    metInt32s = true;
                                    int val = AInt32SerializerDeserializer.getInt(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case INT64: {
                                    metInt64s = true;
                                    long val = AInt64SerializerDeserializer.getLong(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case FLOAT: {
                                    metFloats = true;
                                    float val = AFloatSerializerDeserializer.getFloat(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case DOUBLE: {
                                    metDoubles = true;
                                    double val = ADoubleSerializerDeserializer.getDouble(inputVal.getBytes(), 1);
                                    sum += val;
                                    break;
                                }
                                case NULL: {
                                    metNull = true;
                                    break;
                                }
                                default: {
                                    throw new NotImplementedException("Cannot compute SUM for values of type "
                                            + typeTag);
                                }
                            }
                        }

                        pos = start;
                        BufferSerDeUtil.writeBoolean(metInt8s, state, pos++);
                        BufferSerDeUtil.writeBoolean(metInt16s, state, pos++);
                        BufferSerDeUtil.writeBoolean(metInt32s, state, pos++);
                        BufferSerDeUtil.writeBoolean(metInt64s, state, pos++);
                        BufferSerDeUtil.writeBoolean(metFloats, state, pos++);
                        BufferSerDeUtil.writeBoolean(metDoubles, state, pos++);
                        BufferSerDeUtil.writeBoolean(metNull, state, pos++);
                        BufferSerDeUtil.writeDouble(sum, state, pos);
                    }

                    @SuppressWarnings("unchecked")
                    @Override
                    public void finish(byte[] state, int start, int len, DataOutput out) throws AlgebricksException {
                        int pos = start;
                        boolean metInt8s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt16s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt32s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metInt64s = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metFloats = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metDoubles = BufferSerDeUtil.getBoolean(state, pos++);
                        boolean metNull = BufferSerDeUtil.getBoolean(state, pos++);
                        double sum = BufferSerDeUtil.getDouble(state, pos);
                        try {
                            if (metNull) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.ANULL);
                                serde.serialize(ANull.NULL, out);
                            } else if (metDoubles) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.ADOUBLE);
                                aDouble.setValue(sum);
                                serde.serialize(aDouble, out);
                            } else if (metFloats) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.AFLOAT);
                                aFloat.setValue((float) sum);
                                serde.serialize(aFloat, out);
                            } else if (metInt64s) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.AINT64);
                                aInt64.setValue((long) sum);
                                serde.serialize(aInt64, out);
                            } else if (metInt32s) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.AINT32);
                                aInt32.setValue((int) sum);
                                serde.serialize(aInt32, out);
                            } else if (metInt16s) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.AINT16);
                                aInt16.setValue((short) sum);
                                serde.serialize(aInt16, out);
                            } else if (metInt8s) {
                                serde = AqlSerializerDeserializerProvider.INSTANCE
                                        .getSerializerDeserializer(BuiltinType.AINT8);
                                aInt8.setValue((byte) sum);
                                serde.serialize(aInt8, out);
                            } else {
                                GlobalConfig.ASTERIX_LOGGER.fine("SUM aggregate ran over empty input.");
                            }

                        } catch (IOException e) {
                            throw new AlgebricksException(e);
                        }

                    }

                    @Override
                    public void finishPartial(byte[] state, int start, int len, DataOutput out)
                            throws AlgebricksException {
                        finish(state, start, len, out);
                    }
                };
            }
        };
    }

}