Implemented grammer loading

src/StringReader.cpp

@@ -0,0 +1,103 @@
+#include "StringReader.h"
+
+StringReader::StringReader()
+{
+    str_pos = 0;
+}
+
+StringReader::StringReader(std::string inputString)
+{
+    str_pos = 0;
+    setString(inputString);
+}
+
+StringReader::~StringReader()
+{
+    //dtor
+}
+
+void StringReader::setString(std::string inputString)
+{
+    rd_string = inputString;
+    end_reached = false;
+}
+
+std::string StringReader::word(bool truncateEnd)
+{
+    std::vector<std::string> stop_chars;
+    stop_chars.push_back(" ");
+    stop_chars.push_back("\n");
+    stop_chars.push_back("\t");
+    
+
+    std::string result = getTokens(stop_chars, truncateEnd);
+    while (result == " " || result == "\n" || result == "\t")
+    {
+        result = getTokens(stop_chars, truncateEnd);
+    }
+    return(result);
+}
+
+std::string StringReader::line(bool truncateEnd)
+{
+    std::vector<std::string> stop_chars;
+    stop_chars.push_back("\n");
+    return getTokens(stop_chars, truncateEnd);
+}
+
+std::string StringReader::getTokens(std::vector<std::string> stop_chars, bool truncateEnd)
+{
+    int found_pos, new_found_pos;
+    std::string stop_char;
+
+    found_pos = rd_string.find(stop_chars[0], str_pos);
+    stop_char = stop_chars[0];
+
+    for (unsigned int i = 1; i < stop_chars.size(); i++)
+    {
+        new_found_pos = rd_string.find(stop_chars[i], str_pos);
+        
+        //Ok, if the position we found is closer than what we have and is not the end of file, OR the position we are at is the end of file
+        //assign the new found position to the currrent found position
+        if ( ((new_found_pos <= found_pos) && (new_found_pos != std::string::npos)) || found_pos == std::string::npos )
+        {
+            found_pos = new_found_pos;
+            stop_char = stop_chars[i];
+        }
+    }
+
+    if (found_pos == str_pos)                                   //We are at the endline
+    {
+        str_pos++;
+        return stop_char;
+    } else if (found_pos == std::string::npos)                         //We are at the end of the file
+    {
+        //End of String
+        end_reached = true;
+        std::cout << "Reached end of file!\n";
+        return "";
+    } else {
+
+        std::string string_section;
+
+        if (truncateEnd)                                       //If we want to get rid of the delimiting character, which is the default, don't add the last char. Note we have to increase str_pos by one manually later
+            found_pos -= 1;
+
+        for (; str_pos <= found_pos; str_pos++)
+        {
+            string_section += rd_string[str_pos];
+        }
+
+        if (truncateEnd)                                       //Ok, we didn't add the last char, but str_pos now points at that char. So we move it one ahead.
+            str_pos++;
+        return string_section;
+    }
+}
+
+std::string StringReader::truncateEnd(std::string to_truncate)
+{
+    std::string to_return = "";
+    for (unsigned int i = 0; i < to_truncate.length()-1; i++)
+        to_return = to_return + to_truncate[i];
+    return to_return;
+}