Moves all config migration mappings to its own file

src/main/java/net/knarcraft/stargate/utility/FileHelper.java

@@ -0,0 +1,125 @@
+package net.knarcraft.stargate.utility;
+
+import org.bukkit.ChatColor;
+
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+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.io.OutputStreamWriter;
+import java.nio.charset.StandardCharsets;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Helper class for reading files
+ */
+public final class FileHelper {
+
+    private FileHelper() {
+
+    }
+
+    /**
+     * Gets a buffered reader from a string pointing to a file
+     *
+     * @param file <p>The file to read</p>
+     * @return <p>A buffered reader reading the file</p>
+     */
+    public static InputStream getInputStreamForInternalFile(String file) {
+        return FileHelper.class.getResourceAsStream(file);
+    }
+
+    /**
+     * Gets a buffered reader from a string pointing to a file
+     *
+     * @param file <p>The file to read</p>
+     * @return <p>A buffered reader reading the file</p>
+     * @throws FileNotFoundException <p>If the given file does not exist</p>
+     */
+    public static BufferedReader getBufferedReaderFromString(String file) throws FileNotFoundException {
+        FileInputStream fileInputStream = new FileInputStream(file);
+        return getBufferedReaderFromInputStream(fileInputStream);
+    }
+
+    /**
+     * Gets a buffered reader from an input stream
+     *
+     * @param inputStream <p>The input stream to read</p>
+     * @return <p>A buffered reader reading the stream</p>
+     */
+    public static BufferedReader getBufferedReaderFromInputStream(InputStream inputStream) {
+        InputStreamReader inputStreamReader = new InputStreamReader(inputStream, StandardCharsets.UTF_8);
+        return new BufferedReader(inputStreamReader);
+    }
+
+    /**
+     * Gets a buffered writer from a string pointing to a file
+     *
+     * @param file <p>The file to write to</p>
+     * @return <p>A buffered writer writing to the file</p>
+     * @throws FileNotFoundException <p>If the file does not exist</p>
+     */
+    public static BufferedWriter getBufferedWriterFromString(String file) throws FileNotFoundException {
+        FileOutputStream fileOutputStream = new FileOutputStream(file);
+        OutputStreamWriter outputStreamWriter = new OutputStreamWriter(fileOutputStream, StandardCharsets.UTF_8);
+        return new BufferedWriter(outputStreamWriter);
+    }
+
+    /**
+     * Reads key value pairs from an input stream
+     *
+     * @param bufferedReader <p>The buffered reader to read</p>
+     * @return <p>A map containing the read pairs</p>
+     * @throws IOException <p>If unable to read from the stream</p>
+     */
+    public static Map<String, String> readKeyValuePairs(BufferedReader bufferedReader) throws IOException {
+
+        Map<String, String> readPairs = new HashMap<>();
+
+        String line = bufferedReader.readLine();
+        boolean firstLine = true;
+        while (line != null) {
+            // Strip UTF BOM
+            if (firstLine) {
+                line = removeUTF8BOM(line);
+                firstLine = false;
+            }
+            //Split at first "="
+            int equalSignIndex = line.indexOf('=');
+            if (equalSignIndex == -1) {
+                line = bufferedReader.readLine();
+                continue;
+            }
+
+            //Read the line
+            String key = line.substring(0, equalSignIndex);
+            String value = ChatColor.translateAlternateColorCodes('&', line.substring(equalSignIndex + 1));
+            readPairs.put(key, value);
+
+            line = bufferedReader.readLine();
+        }
+        bufferedReader.close();
+
+        return readPairs;
+    }
+
+    /**
+     * Removes the UTF-8 Byte Order Mark if present
+     *
+     * @param string <p>The string to remove the BOM from</p>
+     * @return <p>A string guaranteed without a BOM</p>
+     */
+    private static String removeUTF8BOM(String string) {
+        String UTF8_BOM = "\uFEFF";
+        if (string.startsWith(UTF8_BOM)) {
+            string = string.substring(1);
+        }
+        return string;
+    }
+
+}