/*
 * Copyright 2006-2007 Jeremias Maerki.
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

using System.Text;

namespace ZXing.Datamatrix.Encoder
{
   internal sealed class TextEncoder : C40Encoder
   {
      override public int EncodingMode
      {
         get { return Encodation.TEXT; }
      }

      override protected int encodeChar(char c, StringBuilder sb)
      {
         if (c == ' ')
         {
            sb.Append('\u0003');
            return 1;
         }
         if (c >= '0' && c <= '9')
         {
            sb.Append((char)(c - 48 + 4));
            return 1;
         }
         if (c >= 'a' && c <= 'z')
         {
            sb.Append((char)(c - 97 + 14));
            return 1;
         }
         if (c >= '\u0000' && c <= '\u001f')
         {
            sb.Append('\u0000'); //Shift 1 Set
            sb.Append(c);
            return 2;
         }
         if (c >= '!' && c <= '/')
         {
            sb.Append('\u0001'); //Shift 2 Set
            sb.Append((char)(c - 33));
            return 2;
         }
         if (c >= ':' && c <= '@')
         {
            sb.Append('\u0001'); //Shift 2 Set
            sb.Append((char)(c - 58 + 15));
            return 2;
         }
         if (c >= '[' && c <= '_')
         {
            sb.Append('\u0001'); //Shift 2 Set
            sb.Append((char)(c - 91 + 22));
            return 2;
         }
         if (c == '\u0060')
         {
            sb.Append('\u0002'); //Shift 3 Set
            sb.Append((char)(c - 96));
            return 2;
         }
         if (c >= 'A' && c <= 'Z')
         {
            sb.Append('\u0002'); //Shift 3 Set
            sb.Append((char)(c - 65 + 1));
            return 2;
         }
         if (c >= '{' && c <= '\u007f')
         {
            sb.Append('\u0002'); //Shift 3 Set
            sb.Append((char)(c - 123 + 27));
            return 2;
         }
         if (c >= '\u0080')
         {
            sb.Append("\u0001\u001e"); //Shift 2, Upper Shift
            int len = 2;
            len += encodeChar((char)(c - 128), sb);
            return len;
         }
         HighLevelEncoder.illegalCharacter(c);
         return -1;
      }
   }
}