// Copyright 2011 Google Inc. All Rights Reserved.
//
// Licensed 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.

package com.hughes.android.dictionary.engine;

import com.ibm.icu.text.Transliterator;

import java.util.Comparator;

public class NormalizeComparator implements Comparator<String> {

    private final Transliterator normalizer;
    private final Comparator<Object> comparator;
    private final int version;

    public NormalizeComparator(final Transliterator normalizer,
                               final Comparator<Object> comparator, int version) {
        this.normalizer = normalizer;
        this.comparator = comparator;
        this.version = version;
    }

    public static String withoutDash(final String a) {
        return a.replace("-", "").replace("þ", "th").replace("Þ", "Th");
    }

    // Handles comparison between items containing "-".
    // Also replaces other problematic cases like "thorn".
    public static int compareWithoutDash(final String a, final String b, final Comparator<Object> c, int version) {
        if (version < 7) return 0;
        String s1 = withoutDash(a);
        String s2 = withoutDash(b);
        return c.compare(s1, s2);
    }

    @Override
    public int compare(final String s1, final String s2) {
        final String n1 = normalizer == null ? s1.toLowerCase() : normalizer.transform(s1);
        final String n2 = normalizer == null ? s2.toLowerCase() : normalizer.transform(s2);
        int cn = compareWithoutDash(n1, n2, comparator, version);
        if (cn != 0) {
            return cn;
        }
        cn = comparator.compare(n1, n2);
        if (cn != 0) {
            return cn;
        }
        return comparator.compare(s1, s2);
    }

}