/*

 * Copyright (C) 2007-2010 Júlio Vilmar Gesser.

 * Copyright (C) 2011, 2013-2021 The JavaParser Team.

 *

 * This file is part of JavaParser.

 *

 * JavaParser can be used either under the terms of

 * a) the GNU Lesser General Public License as published by

 *     the Free Software Foundation, either version 3 of the License, or

 *     (at your option) any later version.

 * b) the terms of the Apache License

 *

 * You should have received a copy of both licenses in LICENCE.LGPL and

 * LICENCE.APACHE. Please refer to those files for details.

 *

 * JavaParser 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.

 */

package com.github.javaparser;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.io.InputStream;

import java.io.Reader;

import java.nio.charset.Charset;

import java.nio.file.Files;

import java.nio.file.Path;

import static com.github.javaparser.utils.Utils.assertNotNull;

/**

 * Factory for providers of source code for JavaParser. Providers that have no parameter for encoding but need it will

 * use UTF-8.

 */

public final class Providers {

    public static final Charset UTF8 = Charset.forName("utf-8");

    private Providers() {

    }

    public static Provider provider(Reader reader) {

        return new StreamProvider(assertNotNull(reader));

    }

    public static Provider provider(InputStream input, Charset encoding) {

        assertNotNull(input);

        assertNotNull(encoding);

        try {

            return new StreamProvider(input, encoding.name());

        } catch (IOException e) {

            // The only one that is thrown is UnsupportedCharacterEncodingException,

            // and that's a fundamental problem, so runtime exception.

            throw new RuntimeException(e);

        }

    }

    public static Provider provider(InputStream input) {

        return provider(input, UTF8);

    }

    public static Provider provider(File file, Charset encoding) throws FileNotFoundException {

        return provider(new FileInputStream(assertNotNull(file)), assertNotNull(encoding));

    }

    public static Provider provider(File file) throws FileNotFoundException {

        return provider(assertNotNull(file), UTF8);

    }

    public static Provider provider(Path path, Charset encoding) throws IOException {

        return provider(Files.newInputStream(assertNotNull(path)), assertNotNull(encoding));

    }

    public static Provider provider(Path path) throws IOException {

        return provider(assertNotNull(path), UTF8);

    }

    public static Provider provider(String source) {

        return new StringProvider(assertNotNull(source));

    }

    /**

     * Provide a Provider from the resource found in class loader with the provided encoding.<br> As resource is

     * accessed through a class loader, a leading "/" is not allowed in pathToResource

     */

    public static Provider resourceProvider(ClassLoader classLoader, String pathToResource, Charset encoding) throws IOException {

        InputStream resourceAsStream = classLoader.getResourceAsStream(pathToResource);

        if (resourceAsStream == null) {

            throw new IOException("Cannot find " + pathToResource);

        }

        return provider(resourceAsStream, encoding);

    }

    /**

     * Provide a Provider from the resource found in the current class loader with the provided encoding.<br> As

     * resource is accessed through a class loader, a leading "/" is not allowed in pathToResource

     */

    public static Provider resourceProvider(String pathToResource, Charset encoding) throws IOException {

        ClassLoader classLoader = Provider.class.getClassLoader();

        return resourceProvider(classLoader, pathToResource, encoding);

    }

    /**

     * Provide a Provider from the resource found in the current class loader with UTF-8 encoding.<br> As resource is

     * accessed through a class loader, a leading "/" is not allowed in pathToResource

     */

    public static Provider resourceProvider(String pathToResource) throws IOException {

        return resourceProvider(pathToResource, UTF8);

    }

    public interface PreProcessor {

        Provider process(Provider innerProvider);

    }

}