From c69bc74b4b03265508885a2f0aa0ec6e59f02ae0 Mon Sep 17 00:00:00 2001
From: Michael Bayne <mdb@fb.com>
Date: Sun, 3 Apr 2016 08:55:25 -0700
Subject: [PATCH] Allow indent width to be customized in generated code.

---
 .../com/samskivert/depot/tools/GenRecord.java | 52 ++++++++++++++++---
 1 file changed, 44 insertions(+), 8 deletions(-)

diff --git a/src/main/java/com/samskivert/depot/tools/GenRecord.java b/src/main/java/com/samskivert/depot/tools/GenRecord.java
index df1e225..5372560 100644
--- a/src/main/java/com/samskivert/depot/tools/GenRecord.java
+++ b/src/main/java/com/samskivert/depot/tools/GenRecord.java
@@ -6,6 +6,7 @@ package com.samskivert.depot.tools;
 
 import java.io.*;
 import java.lang.annotation.Annotation;
+import java.net.URL;
 import java.nio.charset.Charset;
 import java.util.Arrays;
 import java.util.List;
@@ -16,14 +17,17 @@ import java.util.regex.Pattern;
 
 import java.lang.reflect.*;
 
+import com.google.common.base.Charsets;
 import com.google.common.base.Function;
 import com.google.common.base.Joiner;
+import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
 import com.google.common.collect.Sets;
 import com.google.common.io.CharStreams;
 import com.google.common.io.Files;
+import com.google.common.io.Resources;
 
 import com.samskivert.depot.PersistentRecord;
 import com.samskivert.depot.annotation.GeneratedValue;
@@ -43,6 +47,14 @@ public abstract class GenRecord
         }
     }
 
+    /**
+     * Configures the number of spaces used for each indentation level in generated code. The
+     * default is four.
+     */
+    public void setIndentWidth (int spaces) {
+       _indentWidth = spaces;
+    }
+
     /**
      * Processes a persistent record source file.
      */
@@ -255,9 +267,9 @@ public abstract class GenRecord
         if (fsection.length() > 0) {
             String prev = get(lines, nstart-1);
             if (!isBlank(prev) && !prev.equals("{")) pout.println();
-            pout.println("    " + FIELDS_START);
+            pout.println(makeIndent(1) + FIELDS_START);
             pout.write(fsection.toString());
-            pout.println("    " + FIELDS_END);
+            pout.println(makeIndent(1) + FIELDS_END);
             if (!isBlank(get(lines, nend))) pout.println();
         }
         for (int ii = nend; ii < mstart; ii++) {
@@ -266,9 +278,9 @@ public abstract class GenRecord
 
         if (msection.length() > 0) {
             if (!isBlank(get(lines, mstart-1))) pout.println();
-            pout.println("    " + METHODS_START);
+            pout.println(makeIndent(1) + METHODS_START);
             pout.write(msection.toString());
-            pout.println("    " + METHODS_END);
+            pout.println(makeIndent(1) + METHODS_END);
             String next = get(lines, mend);
             if (!isBlank(next) && !next.equals("}")) pout.println();
         }
@@ -322,11 +334,13 @@ public abstract class GenRecord
     protected String mergeTemplate (String tmpl, Map<String, String> subs)
     {
         try {
-            InputStream in = getClass().getClassLoader().getResourceAsStream(tmpl);
-            String text = CharStreams.toString(new InputStreamReader(in, "UTF-8"));
-            text = text.replace("\n", System.getProperty("line.separator"));
+            URL url = getClass().getClassLoader().getResource(tmpl);
+            List<String> lines = Resources.readLines(url, Charsets.UTF_8);
+            adjustIndent(lines);
+            String lineSep = System.getProperty("line.separator");
+            String text = Joiner.on(lineSep).join(lines) + lineSep;
             for (Map.Entry<String, String> entry : subs.entrySet()) {
-                text = text.replaceAll("@"+entry.getKey()+"@", entry.getValue());
+                text = text.replace("@"+entry.getKey()+"@", entry.getValue());
             }
             return text;
         } catch (Exception e) {
@@ -334,6 +348,18 @@ public abstract class GenRecord
         }
     }
 
+    protected void adjustIndent (List<String> lines) {
+        int tmplWidth = TEMPLATE_INDENT_SPACES;
+        for (int ii = 0, ll = lines.size(); ii < ll; ii++) {
+            String line = lines.get(ii);
+            if (line.length() == 0) continue;
+            int cc = 0;
+            while (line.charAt(cc) == ' ' && cc < line.length()) cc++;
+            int depth = cc / tmplWidth;
+            lines.set(ii, makeIndent(depth) + line.substring(depth * tmplWidth));
+        }
+    }
+
     protected static boolean hasAnnotation (Field field, Class<?> annotation)
     {
         // iterate because getAnnotation() fails if we're dealing with multiple classloaders
@@ -531,6 +557,10 @@ public abstract class GenRecord
         return nname.toString();
     }
 
+    protected String makeIndent (int depth) {
+        return Strings.repeat(" ", depth * _indentWidth);
+    }
+
     /** Used to do our own classpath business. */
     protected final ClassLoader _cloader;
 
@@ -538,6 +568,9 @@ public abstract class GenRecord
      * loaded derived classes. */
     protected final Class<?> _prclass;
 
+    /** The number of spaces to use for an indent. */
+    protected int _indentWidth = TEMPLATE_INDENT_SPACES;
+
     /** Specifies the path to the name code template. */
     protected static final String PROTO_TMPL = "com/samskivert/depot/tools/record_proto.tmpl";
 
@@ -547,6 +580,9 @@ public abstract class GenRecord
     /** Specifies the path to the key code template. */
     protected static final String KEY_TMPL = "com/samskivert/depot/tools/record_key.tmpl";
 
+    /** The number of spaces for each indent used by the template files. */
+    protected static final int TEMPLATE_INDENT_SPACES = 4;
+
     // markers
     protected static final String MARKER = "// AUTO-GENERATED: ";
     protected static final String FIELDS_START = MARKER + "FIELDS START";