From f2c588ef239f34fd363db090a3b35feec7cd7132 Mon Sep 17 00:00:00 2001
From: Prajwal Goudar <prajwaldgoudar@gmail.com>
Date: Mon, 25 Mar 2019 19:44:38 +0530
Subject: [PATCH] support for loading fonts dynamically with an option to
 choose level (#26)

* support for loading fonts dynamically with an option to choose level("easy","medium","hard")

* removed unwanted method

* changes made as required
---
 src/main/java/lc/FontFunCaptcha.java  | 43 ++++++++++++++++++++++-----
 src/main/java/lc/HelperFunctions.java |  4 +++
 src/main/scala/lc/Main.scala          |  2 +-
 3 files changed, 40 insertions(+), 9 deletions(-)

diff --git a/src/main/java/lc/FontFunCaptcha.java b/src/main/java/lc/FontFunCaptcha.java
index 8952613..3603b23 100644
--- a/src/main/java/lc/FontFunCaptcha.java
+++ b/src/main/java/lc/FontFunCaptcha.java
@@ -4,7 +4,8 @@ import javax.imageio.ImageIO;
 import java.awt.*;
 import java.awt.image.BufferedImage;
 import java.io.ByteArrayOutputStream;
-import java.util.Random;
+import java.io.File;
+import java.io.FilenameFilter;
 
 public class FontFunCaptcha implements ChallengeProvider{
 
@@ -12,19 +13,44 @@ public class FontFunCaptcha implements ChallengeProvider{
         return "FontFunCaptcha";
     }
 
-    private byte[] fontFun(String captchaText){
-        String[] fonts = {"Captcha Code","Mom'sTypewriter","Annifont","SF Intoxicated Blues",
-                "BeachType","Batmos","Barbecue","Bad Seed","Aswell","Alien Marksman"};
+    private String getFontName(String path, String level){
+        File file = new File(path+level+"/");
+        FilenameFilter txtFileFilter = new FilenameFilter() {
+            @Override
+            public boolean accept(File dir, String name)
+            {
+                if(name.endsWith(".ttf"))
+                    return true;
+                else
+                    return false;
+            }
+        };
+        File[] files = file.listFiles(txtFileFilter);
+        return path+level.toLowerCase()+"/"+files[HelperFunctions.randomNumber(0,files.length-1)].getName();
+    }
+
+    private Font loadCustomFont(String level, String path) {
+        String fontName = getFontName(path,level);
+        try{
+            Font font = Font.createFont(Font.TRUETYPE_FONT, new File(fontName));
+            font = font.deriveFont(Font.PLAIN, 48f);
+            return font;
+        } catch (Exception e){
+            e.printStackTrace();
+        }
+        return null;
+    }
+
+    private byte[] fontFun(String captchaText, String level, String path){
         String[] colors = {"#f68787","#f8a978","#f1eb9a","#a4f6a5"};
         BufferedImage img = new BufferedImage(350, 100, BufferedImage.TYPE_INT_RGB);
         Graphics2D graphics2D = img.createGraphics();
-        Random rand = new Random();
         for(int i=0; i< captchaText.length(); i++) {
-            Font font = new Font(fonts[rand.nextInt(10)], Font.ROMAN_BASELINE, 48);
+            Font font = loadCustomFont(level,path);
             graphics2D.setFont(font);
             FontMetrics fontMetrics = graphics2D.getFontMetrics();
             HelperFunctions.setRenderingHints(graphics2D);
-            graphics2D.setColor(Color.decode(colors[rand.nextInt(4)]));
+            graphics2D.setColor(Color.decode(colors[HelperFunctions.randomNumber(0,3)]));
             graphics2D.drawString(String.valueOf(captchaText.charAt(i)), (i * 48), fontMetrics.getAscent());
         }
         graphics2D.dispose();
@@ -39,7 +65,8 @@ public class FontFunCaptcha implements ChallengeProvider{
 
     public Challenge returnChallenge() {
         String secret = HelperFunctions.randomString(7);
-        return new Challenge(fontFun(secret),"png",secret.toLowerCase());
+        String path = "./lib/fonts/";
+        return new Challenge(fontFun(secret,"medium",path),"png",secret.toLowerCase());
     }
 
     public boolean checkAnswer(String secret, String answer){
diff --git a/src/main/java/lc/HelperFunctions.java b/src/main/java/lc/HelperFunctions.java
index c1f0b2a..e3882ca 100644
--- a/src/main/java/lc/HelperFunctions.java
+++ b/src/main/java/lc/HelperFunctions.java
@@ -20,4 +20,8 @@ public class HelperFunctions {
         }
         return stringBuilder.toString();
     }
+
+    public static int randomNumber(int min,int max){
+        return (int)(Math.random() * ((max - min) +1)) + min;
+    }
 }
diff --git a/src/main/scala/lc/Main.scala b/src/main/scala/lc/Main.scala
index bae01a4..9b70ad0 100644
--- a/src/main/scala/lc/Main.scala
+++ b/src/main/scala/lc/Main.scala
@@ -45,7 +45,7 @@ class Captcha {
   
   def getChallenge(param: Parameters): Id = {
   	//TODO: eval params to choose a provider
-  	val providerMap = "GifCaptcha"
+  	val providerMap = "FontFunCaptcha"
   	val provider = filters(providerMap)
     val challenge = provider.returnChallenge()
     val blob = new ByteArrayInputStream(challenge.content)