CompositeId.java

package eu.f3rog.db;

import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.annotation.StringDef;
import android.text.TextUtils;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * Class {@link CompositeId}.
 *
 * @author Frantisek Gazo
 * @version 2015-09-09
 */
public class CompositeId {

    public static final class Builder {

        @Nullable
        private CompositeId mCompositeId;

        public Builder() {
            mCompositeId = new CompositeId();
        }

        public Builder add(@Nullable Integer id, @NonNull @Tag String idTag) {
            return add((id != null) ? "" + id : null, idTag);
        }

        public Builder add(@Nullable Long id, @NonNull @Tag String idTag) {
            return add((id != null) ? "" + id : null, idTag);
        }

        public Builder add(@Nullable String id, @NonNull @Tag String idTag) {
            if (mCompositeId != null && id != null && !id.isEmpty()) {
                mCompositeId.add(id, idTag);
            } else {
                mCompositeId = null;
            }
            return this;
        }

        public Builder add(@Nullable CompositeIdObject obj) {
            if (mCompositeId != null && obj != null && obj.getDatabaseId() != null && !obj.getDatabaseId().isEmpty()) {
                mCompositeId.add(obj.getDatabaseId());
            } else {
                mCompositeId = null;
            }
            return this;
        }

        public Builder add(@Nullable CompositeIdObject obj, @Tag String... onlyIdTags) {
            add((obj != null) ? obj.getDatabaseId() : null, onlyIdTags);
            return this;
        }

        public Builder add(@Nullable CompositeId cid, @Tag String... onlyIdTags) {
            if (mCompositeId != null && cid != null) {
                for (String tag : onlyIdTags) {
                    String id = cid.getId(tag);
                    if (id != null) {
                        mCompositeId.add(id, tag);
                    } else {
                        mCompositeId = null;
                        break;
                    }
                }
            } else {
                mCompositeId = null;
            }
            return this;
        }

        public Builder keep(@NonNull @Tag String... idTags) {
            if (mCompositeId != null) {
                mCompositeId.keepOnly(idTags);
            }
            return this;
        }

        public Builder remove(@NonNull @Tag String... idTags) {
            if (mCompositeId != null) {
                mCompositeId.remove(idTags);
            }
            return this;
        }

        @Nullable
        public CompositeId build() {
            return mCompositeId;
        }

        @Nullable
        public String buildString() {
            return (mCompositeId != null) ? mCompositeId.toString() : null;
        }

        @Nullable
        public String buildRegex() {
            if (mCompositeId != null) {
                return mCompositeId.createRegexId();
            } else {
                return null;
            }
        }

        public static CompositeId buildFrom(String stringId) {
            if (TextUtils.isEmpty(stringId)) {
                return null;
            } else {
                return new CompositeId(stringId);
            }
        }

    }

    //region TAGS ----------------------------------------------

    @Retention(RetentionPolicy.SOURCE)
    @StringDef({
            SOME_TAG,
    })
    public @interface Tag {
    }

    // DO NOT CHANGE tags in SubjectFormDatum because filter expects that Subject.COLUMN_DATABASE_ID is contained in SubjectFormDatum.COLUMN_DATABASE_ID as is
    public static final String END = "<END>";
    public static final String SOME_TAG = "<Tag>";

    /**
     * ATTENTION : All tags have to be the same length !!!
     */
    private static final int TAG_LENGTH = 5;

    public static final String SEPARATOR = "#/#";
    private static final String REGEX_SEPARATOR = "%";

    //endregion TAGS ----------------------------------------------

    @Nullable
    private String mStringId;
    @Nullable
    private Map<String, String> mIds;

    /**
     * Constructs new composite ID.
     */
    private CompositeId() {
        mStringId = "";
        mIds = new HashMap<>();
    }

    /**
     * Constructs new composite ID.
     *
     * @param stringId String representation of composite ID.
     */
    private CompositeId(String stringId) {
        mStringId = stringId;
        mIds = parseIds(mStringId);
    }

    /**
     * Returns ID part based on given tag.
     */
    @Nullable
    public String getId(@Tag String idTag) {
        return getIds().get(idTag);
    }

    @Nullable
    public Long getLongId(@Tag String idTag) {
        String id = getId(idTag);
        return (id != null) ? Long.parseLong(id) : null;
    }

    private void add(@NonNull String id, @Tag String idTag) {
        getIds().put(idTag, id);
        mStringId = null;
    }

    private void add(@NonNull CompositeId compositeId) {
        getIds().putAll(compositeId.getIds());
        mStringId = null;
    }

    private void remove(@Tag String... idTags) {
        getIds().keySet().removeAll(Arrays.asList(idTags));
        mStringId = null;
    }

    private void keepOnly(@Tag String... idTags) {
        getIds().keySet().retainAll(Arrays.asList(idTags));
        mStringId = null;
    }

    public boolean containsIdFor(@Tag String idTag) {
        return getIds().containsKey(idTag);
    }

    /**
     * Returns all parts of this composite ID.
     */
    @NonNull
    private Map<String, String> getIds() {
        if (mIds == null) {
            mIds = parseIds(mStringId);
        }
        return mIds;
    }

    @Override
    public String toString() {
        if (mStringId == null) {
            mStringId = buildStringId(mIds, SEPARATOR);
        }
        return mStringId;
    }

    @Override
    public boolean equals(Object o) {
        return o != null && toString().equals(o.toString());
    }

    @Override
    public int hashCode() {
        return toString().hashCode();
    }

    public boolean isEmpty() {
        return getIds().isEmpty();
    }

    private int getPartsCount() {
        return getIds().size();
    }

    /**
     * Creates regex for LIKE query operator.
     */
    private String createRegexId() {
        return REGEX_SEPARATOR + buildStringId(mIds, SEPARATOR + REGEX_SEPARATOR);
    }

    private Map<String, String> parseIds(String stringId) {
        Map<String, String> ids = new HashMap<>();
        if (stringId != null) {
            String[] splitIds = stringId.split(SEPARATOR);
            for (String s : splitIds) {
                ids.put(s.substring(0, TAG_LENGTH), s.substring(TAG_LENGTH, s.length()));
            }
        }
        ids.remove(END);
        return ids;
    }

    private String buildStringId(Map<String, String> ids, String separator) {
        if (ids == null) {
            return "";
        }
        StringBuilder sb = new StringBuilder();
        List<String> tags = new ArrayList<>(ids.keySet());
        Collections.sort(tags);
        String tag;
        for (int i = 0; i < tags.size(); i++) {
            tag = tags.get(i);
            sb.append(tag).append(ids.get(tag)).append(separator);
        }
        sb.append(END);
        return sb.toString();
    }

}