/**
 * Copyright (C) 2009-2015 FoundationDB, LLC
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.foundationdb.server.types.common.funcs;


import com.foundationdb.server.error.InvalidArgumentTypeException;
import com.foundationdb.server.service.blob.BlobRef;
import com.foundationdb.server.service.blob.LobService;
import com.foundationdb.server.types.TScalar;
import com.foundationdb.server.types.TExecutionContext;
import com.foundationdb.server.types.LazyList;
import com.foundationdb.server.types.aksql.aktypes.AkBlob;
import com.foundationdb.server.types.common.types.NoAttrTClass;
import com.foundationdb.server.types.mcompat.mtypes.MNumeric;
import com.foundationdb.server.types.texpressions.TScalarBase;
import com.foundationdb.server.types.texpressions.TInputSetBuilder;
import com.foundationdb.server.types.TOverloadResult;
import com.foundationdb.server.types.value.ValueSource;
import com.foundationdb.server.types.value.ValueTarget;


public class BlobSize extends TScalarBase {
    private NoAttrTClass blobClass;

    public static TScalar blobSize(final NoAttrTClass blob) {
        return new BlobSize(blob);
    }


    private BlobSize(NoAttrTClass blobClass) {
        this.blobClass = blobClass;
    }

    @Override
    protected void buildInputSets(TInputSetBuilder builder) {
        builder.covers(this.blobClass, 0);
    }

    @Override
    protected void doEvaluate(TExecutionContext context, LazyList<? extends ValueSource> inputs, ValueTarget output) {
        long size = 0L;
        BlobRef blobRef;
        if (inputs.get(0).hasAnyValue()) {
            Object o = inputs.get(0).getObject();
            if (o instanceof BlobRef) {
                blobRef = (BlobRef) o;
                String mode = context.getQueryContext().getStore().getConfig().getProperty(AkBlob.RETURN_UNWRAPPED);
                if (mode.equalsIgnoreCase(AkBlob.UNWRAPPED)) {
                    byte[] content = blobRef.getBytes();
                    if (content != null) {
                        size = (long)content.length;
                    }
                }
                else {
                    if (blobRef.isLongLob()) {
                        LobService lobService = context.getQueryContext().getServiceManager().getServiceByClass(LobService.class);
                        size = lobService.sizeBlob(context.getQueryContext().getSession(), blobRef.getId());
                    } else {
                        size = (long) (blobRef.getBytes().length);
                    }
                }
            } else {
                throw new InvalidArgumentTypeException("Should be a blob column");
            }
        }
        output.putInt64(size);
    }

    @Override
    public String displayName() {
        return "BLOB_SIZE";
    }

    @Override
    public String[] registeredNames() {
        return new String[] {displayName(), "octet_length"};
    }

    @Override
    public TOverloadResult resultType() {
        return TOverloadResult.fixed(MNumeric.BIGINT);
    }
}