/**
 * DataCleaner (community edition)
 * Copyright (C) 2014 Neopost - Customer Information Management
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * 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 Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 */
package org.datacleaner.components.convert;

import javax.inject.Inject;
import javax.inject.Named;

import org.datacleaner.api.Alias;
import org.datacleaner.api.Categorized;
import org.datacleaner.api.Configured;
import org.datacleaner.api.Description;
import org.datacleaner.api.InputColumn;
import org.datacleaner.api.InputRow;
import org.datacleaner.api.OutputColumns;
import org.datacleaner.api.Transformer;
import org.datacleaner.components.categories.ConversionCategory;

/**
 * Attempts to convert anything to a Boolean value
 */
@Named("Convert to boolean")
@Description("Converts anything to a boolean (or null).")
@Categorized(ConversionCategory.class)
public class ConvertToBooleanTransformer implements Transformer {

    public static final String[] DEFAULT_TRUE_TOKENS = new String[] { "true", "yes", "1", "x", "y" };
    public static final String[] DEFAULT_FALSE_TOKENS = new String[] { "false", "no", "0", "-", "n" };

    @Inject
    @Configured
    @Alias("Column")
    InputColumn<?>[] input;

    @Configured(required = false)
    Boolean nullReplacement;

    @Configured
    @Description("Text tokens that will translate to 'true'")
    String[] _trueTokens = DEFAULT_TRUE_TOKENS;

    @Configured
    @Description("Text tokens that will translate to 'false'")
    String[] _falseTokens = DEFAULT_FALSE_TOKENS;

    public ConvertToBooleanTransformer(final InputColumn<?>[] input) {
        this.input = input;
    }

    public ConvertToBooleanTransformer() {
        this(null);
    }

    public static Boolean transformValue(final Object value) {
        return transformValue(value, DEFAULT_TRUE_TOKENS, DEFAULT_FALSE_TOKENS);
    }

    public static Boolean transformValue(final Object value, final String[] trueTokens, final String[] falseTokens) {
        Boolean b = null;
        if (value != null) {
            if (value instanceof String) {
                String stringValue = (String) value;
                stringValue = stringValue.trim();

                for (final String token : trueTokens) {
                    if (token.equalsIgnoreCase(stringValue)) {
                        b = true;
                        break;
                    }
                }
                if (b == null) {
                    for (final String token : falseTokens) {
                        if (token.equalsIgnoreCase(stringValue)) {
                            b = false;
                            break;
                        }
                    }
                }
            } else if (value instanceof Number) {
                final Number numberValue = (Number) value;
                if (numberValue.intValue() == 1) {
                    b = true;
                } else if (numberValue.intValue() == 0) {
                    b = false;
                }
            } else if (value instanceof Boolean) {
                b = (Boolean) value;
            }
        }
        return b;
    }

    @Override
    public OutputColumns getOutputColumns() {
        final String[] names = new String[input.length];
        for (int i = 0; i < names.length; i++) {
            names[i] = input[i].getName() + " (as boolean)";
        }
        return new OutputColumns(Boolean.class, names);
    }

    @Override
    public Object[] transform(final InputRow inputRow) {
        final Boolean[] result = new Boolean[input.length];
        for (int i = 0; i < input.length; i++) {
            final Object value = inputRow.getValue(input[i]);
            Boolean b = transformValue(value, _trueTokens, _falseTokens);
            if (b == null) {
                b = nullReplacement;
            }
            result[i] = b;
        }
        return result;
    }

    public String[] getFalseTokens() {
        return _falseTokens;
    }

    public void setFalseTokens(final String[] falseTokens) {
        _falseTokens = falseTokens;
    }

    public InputColumn<?>[] getInput() {
        return input;
    }

    public void setInput(final InputColumn<?>... input) {
        this.input = input;
    }

    public Boolean getNullReplacement() {
        return nullReplacement;
    }

    public void setNullReplacement(final Boolean nullReplacement) {
        this.nullReplacement = nullReplacement;
    }

    public String[] getTrueTokens() {
        return _trueTokens;
    }

    public void setTrueTokens(final String[] trueTokens) {
        _trueTokens = trueTokens;
    }

}