/*
 * Licensed to Crate under one or more contributor license agreements.
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.  Crate licenses this file
 * to you under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.  You may
 * obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * However, if you have executed another commercial license agreement
 * with Crate these terms will supersede the license and you may use the
 * software solely pursuant to the terms of the relevant commercial
 * agreement.
 */

package io.crate.operation.reference.sys.node.local.fs;

import io.crate.monitor.ExtendedFsStats;
import io.crate.operation.reference.NestedObjectExpression;
import io.crate.operation.reference.sys.SysObjectArrayReference;

import java.util.ArrayList;
import java.util.List;

class NodeFsDisksExpression extends SysObjectArrayReference {

    private final ExtendedFsStats extendedFsStats;

    NodeFsDisksExpression(ExtendedFsStats extendedFsStats) {
        this.extendedFsStats = extendedFsStats;
    }

    @Override
    protected List<io.crate.operation.reference.NestedObjectExpression> getChildImplementations() {
        List<io.crate.operation.reference.NestedObjectExpression> diskRefs = new ArrayList<>(extendedFsStats.size());
        for (ExtendedFsStats.Info info : extendedFsStats) {
            diskRefs.add(new NodeFsDiskChildExpression(info));
        }
        return diskRefs;
    }

    private static class NodeFsDiskChildExpression extends NestedObjectExpression {

        private static final String DEV = "dev";
        private static final String SIZE = "size";
        private static final String USED = "used";
        private static final String AVAILABLE = "available";
        private static final String READS = "reads";
        private static final String BYTES_READ = "bytes_read";
        private static final String WRITES = "writes";
        private static final String BYTES_WRITTEN = "bytes_written";

        final ExtendedFsStats.Info fsInfo;

        NodeFsDiskChildExpression(ExtendedFsStats.Info fsInfo) {
            this.fsInfo = fsInfo;
            addChildImplementations();
        }

        private void addChildImplementations() {
            childImplementations.put(DEV, fsInfo::dev);
            childImplementations.put(SIZE, fsInfo::total);
            childImplementations.put(USED, fsInfo::used);
            childImplementations.put(AVAILABLE, fsInfo::available);
            childImplementations.put(READS, fsInfo::diskReads);
            childImplementations.put(BYTES_READ, fsInfo::diskReadSizeInBytes);
            childImplementations.put(WRITES, fsInfo::diskWrites);
            childImplementations.put(BYTES_WRITTEN, fsInfo::diskWriteSizeInBytes);

        }
    }
}