MiscUtils.java

package com.orgzly.android.util;


import android.net.Uri;
import android.support.design.widget.TextInputLayout;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.TextView;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.security.MessageDigest;

public class MiscUtils {
    public static final int SNACKBAR_WITH_ACTION_DURATION = 8000;

    /**
     * Counts lines in a given string. Empty string counts as one line.
     *
     * @param str string
     * @return number of lines in a string
     */
    public static int lineCount(String str) {
        if (str == null) {
            return 0;
        }

        int lines = 1;
        int pos = 0;

        while ((pos = str.indexOf("\n", pos)) != -1) {
            lines++;
            pos++;
        }

        return lines;
    }

    public static String readStringFromFile(File file) throws IOException {
        StringBuffer fileData = new StringBuffer();
        BufferedReader reader = new BufferedReader(new FileReader(file));
        char[] buf = new char[1024];
        int numRead;
        while ((numRead = reader.read(buf)) != -1) {
            String readData = String.valueOf(buf, 0, numRead);
            fileData.append(readData);
        }
        reader.close();
        return fileData.toString();
    }

    public static void writeStringToFile(String str, File file) throws FileNotFoundException {
        PrintWriter out = new PrintWriter(file);
        try {
            out.write(str);
        } finally {
            out.close();
        }
    }

    /**
     * Compares content of two text files.
     * @return null if files match, difference if they don't
     */
    public static String compareFiles(File file1, File file2) throws IOException {
        String result;

        BufferedReader reader1 = new BufferedReader(new FileReader(file1));
        BufferedReader reader2 = new BufferedReader(new FileReader(file2));

        while (true) {
            String line1 = reader1.readLine();
            String line2 = reader2.readLine();

            if (line1 == null && line2 == null) {
                result = null;
                break;

            } else if (line1 == null && line2 != null) {
                result = "file2 has more lines then file1";
                break;

            } else if (line1 != null && line2 == null) {
                result = "file1 has more lines then file2";
                break;

            } else if (! line1.equals(line2)) {
                result = "Files differ:\n" + line1 + "\n" + line2 + "\n";
                break;
            }
        }

        reader1.close();
        reader2.close();

        return result;
    }

    public static void writeStreamToFile(InputStream in, File file) throws IOException {
        OutputStream out = new FileOutputStream(file);
        try {
            byte[] buffer = new byte[1024];
            int len;
            while ((len = in.read(buffer, 0, buffer.length)) != -1) {
                out.write(buffer, 0, len);
            }
        } finally {
            out.close();
        }
    }

    public static void writeFileToStream(File file, OutputStream out) throws IOException {
        InputStream in = new FileInputStream(file);
        try {
            byte[] buffer = new byte[1024];
            int len;
            while ((len = in.read(buffer, 0, buffer.length)) != -1) {
                out.write(buffer, 0, len);
            }

        } finally {
            in.close();
        }
    }

    /**
     * Surround string with curly quotes (a.k.a. smart quotes).
     */
    public static String quotedString(String str) {
        return "“" + str + "”";
    }

    public static long sha1(String s) {
        long l = 0L;

        try {
            MessageDigest md = MessageDigest.getInstance("SHA-1");
            md.update(s.getBytes("UTF-8"));
            byte[] digest = md.digest();

            /* First 64 bits only */
            for (int i = 0; i < 8; ++i) {
                l <<= 8;
                l |= (0xff & digest[i]);
            }

        } catch (Exception e) {
            e.printStackTrace();
        }

        return l;
    }

    public static void copyFile(File src, File dst) throws IOException {
        InputStream in = new FileInputStream(src);
        OutputStream out = new FileOutputStream(dst);

        byte[] buf = new byte[1024];
        int len;
        while ((len = in.read(buf)) > 0) {
            out.write(buf, 0, len);
        }
        in.close();
        out.close();
    }

    /**
     * Clear {@link TextInputLayout} error after its text has been modified.
     */
    public static void clearErrorOnTextChange(final TextView tv, final TextInputLayout til) {
        tv.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                til.setError(null);
            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {
            }

            @Override
            public void afterTextChanged(Editable s) {
            }
        });
    }

    private static boolean isAllowedInUrlEncoded(char c, String allow) {
        return (c >= 'A' && c <= 'Z')
               || (c >= 'a' && c <= 'z')
               || (c >= '0' && c <= '9')
               || "_-!.~'()*".indexOf(c) != -1
               || (allow != null && allow.indexOf(c) != -1);
    }

    private static boolean isHexChar(char c) {
        return (c >= 'A' && c <= 'F') ||
               (c >= 'a' && c <= 'f') ||
               (c >= '0' && c <= '9');
    }

    static boolean uriPathNeedsEncoding(String str) {
        int percentHexCharsLeft = 0;

        for (int i = 0; i < str.length(); i++) {
            char c = str.charAt(i);

            if (! isAllowedInUrlEncoded(c, "/%")) {
                return true;
            }

            if (percentHexCharsLeft-- > 0) {
                // This char must be digit
                if (! isHexChar(c)) {
                    return true;
                }
            }

            if (c == '%') {
                percentHexCharsLeft = 2;
                // Next two characters must be hex now
            }
        }

        if (percentHexCharsLeft > 0) {
            return true;
        }

        return false;
    }

    public static String encodeUri(String str) {
        /* Scheme part. */
        int i = str.indexOf(":");

        if (i != -1) {
            String rest = str.substring(i + 1);

            if (uriPathNeedsEncoding(rest)) {
                return str.substring(0, i + 1) + Uri.encode(str.substring(i + 1), "/");
            }
        }

        return str;
    }
}