Merge pull request #2832 from MediaBrowser/beta

Beta

1 files changed, 191 insertions, 0 deletions

diff --git a/Emby.Server.Implementations/TextEncoding/UniversalDetector/Core/CharsetProber.cs b/Emby.Server.Implementations/TextEncoding/UniversalDetector/Core/CharsetProber.cs
new file mode 100644
index 000000000..3369dd430
--- /dev/null
+++ b/Emby.Server.Implementations/TextEncoding/UniversalDetector/Core/CharsetProber.cs
@@ -0,0 +1,191 @@
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is Mozilla Universal charset detector code.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 2001
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *          Shy Shalom <shooshX@gmail.com>
+ *          Rudi Pettazzi <rudi.pettazzi@gmail.com> (C# port)
+ * 
+ * Alternatively, the contents of this file may be used under the terms of
+ * either the GNU General Public License Version 2 or later (the "GPL"), or
+ * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+using System.IO;
+
+namespace UniversalDetector.Core
+{
+    public enum ProbingState {                            
+        Detecting = 0, // no sure answer yet, but caller can ask for confidence
+        FoundIt = 1,   // positive answer
+        NotMe = 2      // negative answer 
+    };
+
+    public abstract class CharsetProber
+    {
+        protected const float SHORTCUT_THRESHOLD = 0.95F;
+
+        protected ProbingState state;
+        
+        // ASCII codes
+        private const byte SPACE = 0x20;
+        private const byte CAPITAL_A = 0x41;
+        private const byte CAPITAL_Z = 0x5A;
+        private const byte SMALL_A = 0x61;
+        private const byte SMALL_Z = 0x7A;
+        private const byte LESS_THAN = 0x3C;        
+        private const byte GREATER_THAN = 0x3E;
+        
+        /// <summary>
+        /// Feed data to the prober
+        /// </summary>
+        /// <param name="buf">a buffer</param>
+        /// <param name="offset">offset into buffer</param>
+        /// <param name="len">number of bytes available into buffer</param>
+        /// <returns>
+        /// A <see cref="ProbingState"/>
+        /// </returns>
+        public abstract ProbingState HandleData(byte[] buf, int offset, int len);
+        
+        /// <summary>
+        /// Reset prober state
+        /// </summary>
+        public abstract void Reset();
+
+        public abstract string GetCharsetName();
+        
+        public abstract float GetConfidence();
+        
+        public virtual ProbingState GetState()
+        {
+            return state;
+        }
+
+        public virtual void SetOption()
+        { 
+        
+        }
+
+        public virtual void DumpStatus()
+        { 
+        
+        }
+
+        //
+        // Helper functions used in the Latin1 and Group probers
+        //
+        /// <summary>
+        ///  
+        /// </summary>
+        /// <returns>filtered buffer</returns>
+        protected static byte[] FilterWithoutEnglishLetters(byte[] buf, int offset, int len) 
+        {
+            byte[] result = null;
+
+            using (MemoryStream ms = new MemoryStream(buf.Length)) {
+                
+                bool meetMSB = false;
+                int max = offset + len;
+                int prev = offset;
+                int cur = offset;
+
+                while (cur < max) {
+                    byte b = buf[cur];
+
+                    if ((b & 0x80) != 0) {
+                        meetMSB = true;
+                    } else if (b < CAPITAL_A || (b > CAPITAL_Z && b < SMALL_A)
+                               || b > SMALL_Z) {
+                        if (meetMSB && cur > prev) {
+                            ms.Write(buf, prev, cur - prev);
+                            ms.WriteByte(SPACE);
+                            meetMSB = false;
+                        }
+                        prev = cur + 1;
+                    }
+                    cur++;
+                }
+
+                if (meetMSB && cur > prev)
+                    ms.Write(buf, prev, cur - prev);
+                ms.SetLength(ms.Position);
+                result = ms.ToArray();
+            }
+            return result;
+        }
+
+        /// <summary>
+        /// Do filtering to reduce load to probers (Remove ASCII symbols, 
+        /// collapse spaces). This filter applies to all scripts which contain 
+        /// both English characters and upper ASCII characters.
+        /// </summary>
+        /// <returns>a filtered copy of the input buffer</returns>
+        protected static byte[] FilterWithEnglishLetters(byte[] buf, int offset, int len)
+        {
+            byte[] result = null;
+
+            using (MemoryStream ms = new MemoryStream(buf.Length)) {
+                
+                bool inTag = false;
+                int max = offset + len;
+                int prev = offset;
+                int cur = offset;
+
+                while (cur < max) {
+                    
+                    byte b = buf[cur];
+                    
+                    if (b == GREATER_THAN)
+                        inTag = false;
+                    else if (b == LESS_THAN)
+                        inTag = true;
+
+                    // it's ascii, but it's not a letter
+                    if ((b & 0x80) == 0 && (b < CAPITAL_A || b > SMALL_Z
+                           || (b > CAPITAL_Z && b < SMALL_A))) {
+                        if (cur > prev && !inTag) {
+                            ms.Write(buf, prev, cur - prev);
+                            ms.WriteByte(SPACE);
+                        }
+                        prev = cur + 1;
+                    }
+                    cur++;
+                }
+
+                // If the current segment contains more than just a symbol 
+                // and it is not inside a tag then keep it.
+                if (!inTag && cur > prev)
+                    ms.Write(buf, prev, cur - prev);
+                ms.SetLength(ms.Position);
+                result = ms.ToArray();
+            }
+            return result;
+        }
+    }
+}
+