package com.lookcoder.inschool.utils;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.nio.charset.StandardCharsets;

import java.util.HashMap;

import java.util.Iterator;

import java.util.Map;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/**

 * title: 清除注释

 */

public class ClearComment {

    public static void main(String[] args) throws FileNotFoundException {

        String rootDir = "E:\\文档\\SpringWebMvcSource\\spring-webmvc-4.3.9.RELEASE-sources";

        deepDir(rootDir);

    }

    private static void deepDir(String rootDir) throws FileNotFoundException {

        File folder = new File(rootDir);

        if (folder.isDirectory()) {

            String[] files = folder.list();

            if (files != null) {

                for (String file1 : files) {

                    File file = new File(folder, file1);

                    if (file.isDirectory() && !file.isHidden()) {

                        deepDir(file.getPath());

                    } else if (file.isFile() && file.getName().endsWith(".java")) {

                        clearComment(file.getPath());

                    }

                }

            }

        } else if (folder.isFile() && folder.getName().endsWith(".java")) {

            clearComment(folder.getPath());

        }

    }

    private static void clearComment(String filePathAndName)

            throws FileNotFoundException {

        StringBuilder buffer = new StringBuilder();

        String line = null; // 用来保存每行读取的内容

        InputStream is = new FileInputStream(filePathAndName);

        BufferedReader reader = new BufferedReader(new InputStreamReader(is,

                StandardCharsets.UTF_8));

        try {

            line = reader.readLine();

        } catch (IOException e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        } // 读取第一行

        while (line != null) { // 如果 line 为空说明读完了

            buffer.append(line); // 将读到的内容添加到 buffer 中

            buffer.append("\r\n"); // 添加换行符

            try {

                line = reader.readLine();

            } catch (IOException e) {

                e.printStackTrace();

            } // 读取下一行

        }

        // 1、清除单行的注释，如： //某某，正则为 ：\/\/.*

        // 2、清除单行的注释，如：/** 某某 */，正则为：\/\*\*.*\*\/

        // 3、清除单行的注释，如：/* 某某 */，正则为：\/\*.*\*\/

        // 4、清除多行的注释，如:

        // /* 某某1

        // 某某2

        // */

        // 正则为：.*/\*(.*)\*/.*

        // 5、清除多行的注释，如：

        // /** 某某1

        // 某某2

        // */

        // 正则为：/\*\*(\s*\*\s*.*\s*?)*

        String filecontent = buffer.toString();

        Map<String, String> patterns = new HashMap<String, String>();

        patterns.put("([^:])\\/\\/.*", "$1");// 匹配在非冒号后面的注释，此时就不到再遇到http://

        patterns.put("\\s+\\/\\/.*", "");// 匹配“//”前是空白符的注释

        patterns.put("^\\/\\/.*", "");

        patterns.put("^\\/\\*\\*.*\\*\\/$", "");

        patterns.put("\\/\\*.*\\*\\/", "");

        patterns.put("/\\*(\\s*\\*\\s*.*\\s*?)*\\*\\/", "");

        //patterns.put("/\\*(\\s*\\*?\\s*.*\\s*?)*", "");

        Iterator<String> keys = patterns.keySet().iterator();

        String key, value;

        while (keys.hasNext()) {

            // 经过多次替换

            key = keys.next();

            value = patterns.get(key);

            filecontent = replaceAll(filecontent, key, value);

        }

        // 再输出到原文件

        try {

            File f = new File(filePathAndName);

            if (!f.getParentFile().exists()) {

                final boolean mkdirs = f.getParentFile().mkdirs();

            }

            FileOutputStream out = new FileOutputStream(filePathAndName);

            byte[] bytes = filecontent.getBytes(StandardCharsets.UTF_8);

            out.write(bytes);

            out.flush();

            out.close();

        } catch (IOException e) {

            e.printStackTrace();

        }

    }

    /**

     * @param fileContent   内容

     * @param patternString 匹配的正则表达式

     * @param replace       替换的内容

     */

    public static String replaceAll(String fileContent, String patternString, String replace) {

        String str = "";

        Matcher m;

        Pattern p;

        try {

            p = Pattern.compile(patternString);

            m = p.matcher(fileContent);

            str = m.replaceAll(replace);

        } catch (Exception e) {

            e.printStackTrace();

        }

        return str;

    }

}