/**
 *  Copyright 2005-2015 Red Hat, Inc.
 *
 *  Red Hat 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
 *
 *     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 io.fabric8.common.util;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.Closeable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.io.Writer;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.ZipFile;

/**
 */
public class IOHelpers {

    protected static final int BUFFER_SIZE = 16 * 1024;

    public static void writeTo(File file, InputStream in) throws IOException {
        writeTo(file, in, BUFFER_SIZE);
    }


    /**
     * Writes the given string as data to the given file
     */
    public static void writeTo(File newFile, String text) throws IOException {
        writeTo(newFile, new ByteArrayInputStream(text.getBytes()));
    }

    public static void writeTo(File file, InputStream in, int bufferSize) throws IOException {
        writeTo(new FileOutputStream(file), in, bufferSize, true);
    }

    public static void writeTo(OutputStream outputStream, InputStream in, boolean close) throws IOException {
        writeTo(outputStream, in, BUFFER_SIZE, close);
    }

    public static void writeTo(OutputStream outputStream, InputStream in, int bufferSize, boolean close) throws IOException {
        BufferedOutputStream out = new BufferedOutputStream(outputStream, bufferSize);
        BufferedInputStream bufferedIn = new BufferedInputStream(in, bufferSize);
        while (true) {
            int b = bufferedIn.read();
            if (b >= 0) {
                out.write(b);
            } else {
                in.close();
                if (close) {
                    out.close();
                } else {
                    out.flush();
                }
                return;
            }
        }
    }

    public static void copy(InputStream inputStream, OutputStream outputStream) throws IOException {
        try {
            byte[] buffer = new byte[8192];
            int len;
            for (; ;) {
                len = inputStream.read(buffer);
                if (len > 0) {
                    outputStream.write(buffer, 0, len);
                } else {
                    outputStream.flush();
                    break;
                }
            }
        } finally {
            close(inputStream, outputStream);
        }
    }

    public static void copy(Reader reader, Writer writer) throws IOException {
        try {
            char[] buffer = new char[8192];
            int len;
            for (; ;) {
                len = reader.read(buffer);
                if (len > 0) {
                    writer.write(buffer, 0, len);
                } else {
                    writer.flush();
                    break;
                }
            }
        } finally {
            close(reader, writer);
        }
    }

    public static void close(ZipFile... closeables) {
        for (ZipFile c : closeables) {
            try {
                if (c != null) {
                    c.close();
                }
            } catch (IOException e) {
            }
        }
    }

    public static void close(Closeable... closeables) {
        for (Closeable c : closeables) {
            try {
                if (c != null) {
                    c.close();
                }
            } catch (IOException e) {
            }
        }
    }

    public static String readFully(File file) throws IOException {
        if (!file.isFile()) {
            return null;
        }
        InputStream in = new FileInputStream(file);
        return readFully(in);
    }

    public static String readFully(InputStream in) throws IOException {
        Reader r = new BufferedReader(new InputStreamReader(in));
        return readFully(r);
    }

    public static String readFully(Reader r) throws IOException {
        StringWriter w = new StringWriter();
        try {
            copy(r, w);
            return w.toString();
        } finally {
            close(r, w);
        }
    }

    public static void writeFully(File file, String content) throws IOException {
        if (content == null) {
            file.delete();
        } else {
            Reader r = new StringReader(content);
            Writer w = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file)));
            try {
                copy(r, w);
            } finally {
                close(r, w);
            }
        }
    }

    public static List<String> readLines(File file) throws IOException {
        List<String> overrides = new ArrayList<String>();
        if (file.exists()) {
            InputStream is = new FileInputStream(file);
            try {
                BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                String line = null;
                while ((line = reader.readLine()) != null) {
                    overrides.add(line);
                }
            } finally {
                is.close();
            }
        }
        return overrides;
    }

    public static void writeLines(File file, List<String> lines) throws IOException {
        OutputStream os = new FileOutputStream(file);
        try {
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(os));
            for (String over : lines) {
                writer.write(over);
                writer.newLine();
            }
            writer.close();
        } finally {
            os.close();
        }
    }

    public static String loadFully(URL url) throws IOException {
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        byte[] buf = new byte[4096];
        int l;
        InputStream is = url.openStream();
        try {
            while ((l = is.read(buf)) >= 0) {
                baos.write(buf, 0, l);
            }
        } finally {
            is.close();
        }
        return baos.toString();
    }

}
