/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF 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
 *
 *    https://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 org.grails.cli.interactive.completers

import jline.console.completer.Completer
import jline.console.completer.StringsCompleter

/**
 * JLine Completor that mixes a fixed set of options with file path matches.
 * Fixed options that match will appear first, followed by file path matches.
 *
 * @author Peter Ledbrook
 * @since 2.0
 */
class SimpleOrFileNameCompletor implements Completer {

    private simpleCompletor
    private fileNameCompletor

    SimpleOrFileNameCompletor(List fixedOptions) {
        this(fixedOptions as String[])
    }

    SimpleOrFileNameCompletor(String[] fixedOptions) {
        simpleCompletor = new StringsCompleter(fixedOptions)
        fileNameCompletor = new EscapingFileNameCompletor()
    }

    int complete(String buffer, int cursor, List candidates) {
        // Try the simple completor first...
        def retval = simpleCompletor.complete(buffer, cursor, candidates)

        // ...and then the file path completor. By using the given candidate
        // list with both completors we aggregate the results automatically.
        def fileRetval = fileNameCompletor.complete(buffer, cursor, candidates)

        // If the simple completor has matched, we return its value, otherwise
        // we return whatever the file path matcher returned. This ensures that
        // both simple completor and file path completor candidates appear
        // correctly in the command prompt. If neither competors have matches,
        // we of course return -1.
        if (retval == -1) retval = fileRetval
        return candidates ? retval : -1
    }
}
