/*
 * Copyright (c) 2015 EMC Software LLC
 * All Rights Reserved
 */
package com.emc.sa.service.vipr.block;

import static com.emc.sa.service.ServiceParams.LINKED_SNAPSHOT;
import static com.emc.sa.service.ServiceParams.LINKED_SNAPSHOT_COPYMODE;
import static com.emc.sa.service.ServiceParams.LINKED_SNAPSHOT_COUNT;
import static com.emc.sa.service.ServiceParams.LINKED_SNAPSHOT_NAME;
import static com.emc.sa.service.ServiceParams.SNAPSHOT_SESSION;
import static com.emc.sa.service.ServiceParams.STORAGE_TYPE;
import static com.emc.sa.service.ServiceParams.VOLUMES;

import java.util.List;

import com.emc.sa.asset.providers.BlockProvider;
import com.emc.sa.engine.ExecutionUtils;
import com.emc.sa.engine.bind.Param;
import com.emc.sa.engine.service.Service;
import com.emc.sa.service.vipr.ViPRService;
import com.emc.sa.service.vipr.block.tasks.LinkBlockSnapshot;
import com.emc.storageos.model.DataObjectRestRep;
import com.emc.vipr.client.Tasks;

@Service("LinkBlockSnapshot")
public class LinkBlockSnapshotService extends ViPRService {

    @Param(value = STORAGE_TYPE, required = false)
    protected String storageType;

    @Param(VOLUMES)
    protected List<String> volumeIds;
    
    @Param(SNAPSHOT_SESSION)
    protected List<String> snapshotSessionIds;
    
    @Param(value = LINKED_SNAPSHOT, required = false)
    protected List<String> existingLinkedSnapshotIds;
    
    @Param(value = LINKED_SNAPSHOT_NAME, required = false)
    protected String linkedSnapshotName;
    
    @Param(value = LINKED_SNAPSHOT_COUNT, required = false)
    protected Integer linkedSnapshotCount;
    
    @Param(value = LINKED_SNAPSHOT_COPYMODE, required = false)
    protected String linkedSnapshotCopyMode;

    @Override
    public void precheck() {                                            
        if (linkedSnapshotName != null && !linkedSnapshotName.isEmpty()) {
            // Can not relink an existing snapshot and link a new snapshot at the same time
            if (existingLinkedSnapshotIds != null && !existingLinkedSnapshotIds.isEmpty()) {
                ExecutionUtils.fail("failTask.LinkBlockSnapshot.linkNewAndExistingSnapshot.precheck", new Object[] {}, new Object[] {});
            }                
            // If trying to create a new Snapshot Session and the optional linkedSnapshotName 
            // is populated, make sure that linkedSnapshotCount > 0.                      
            if (linkedSnapshotCount == null || linkedSnapshotCount.intValue() <= 0) {
                ExecutionUtils.fail("failTask.CreateBlockSnapshot.linkedSnapshotCount.precheck", new Object[] {}, new Object[] {});
            }
            // Ensure that copy mode is selected            
            if (linkedSnapshotCopyMode == null
                    || !(BlockProvider.LINKED_SNAPSHOT_COPYMODE_VALUE.equals(linkedSnapshotCopyMode)
                            || BlockProvider.LINKED_SNAPSHOT_NOCOPYMODE_VALUE.equals(linkedSnapshotCopyMode))) {
                ExecutionUtils.fail("failTask.CreateBlockSnapshot.linkedSnapshotCopyMode.precheck", new Object[] {}, new Object[] {});
            }
        } else if (existingLinkedSnapshotIds == null || existingLinkedSnapshotIds.isEmpty()) {
            // If we get here, the user hasn't selected existing linked snapshots to relink and also hasn't
            // filled in the correct information needed for linking a new snapshot.
            ExecutionUtils.fail("failTask.LinkBlockSnapshot.linkAtLeastOneSnapshot.precheck", new Object[] {}, new Object[] {});
        }        
    }

    @Override
    public void execute() {      
        Tasks<? extends DataObjectRestRep> tasks;        
        for (String snapshotSessionId : snapshotSessionIds) {
            tasks = execute(new LinkBlockSnapshot(snapshotSessionId, existingLinkedSnapshotIds, linkedSnapshotName, linkedSnapshotCount, linkedSnapshotCopyMode));
            addAffectedResources(tasks);
        }        
    }
}