PvlKeyword.cpp

 
/* SPDX-License-Identifier: CC0-1.0 */
 
#include <QDebug>
#include <QString>
#include <QRegularExpression>
#include "PvlKeyword.h"
#include "IException.h"
#include "Message.h"
#include "IString.h"
#include "PvlFormat.h"
#include "PvlSequence.h"
 
using namespace std;
using json = nlohmann::json;
namespace Isis {
  PvlKeyword::PvlKeyword() {
    init();
  }
 
 
  PvlKeyword::PvlKeyword(QString name) {
    init();
    setName(name);
  }
 
 
  PvlKeyword::PvlKeyword(QString name, QString value,
                         QString unit) {
    init();
    setName(name);
    addValue(value, unit);
  }
 
 
  PvlKeyword::PvlKeyword(const PvlKeyword &other) {
    init();
    *this = other;
  }
 
 
  PvlKeyword::~PvlKeyword() {
    if (m_units) {
      delete m_units;
      m_units = NULL;
    }
 
    if (m_comments) {
      delete m_comments;
      m_comments = NULL;
    }
 
    if (m_name) {
      delete [] m_name;
      m_name = NULL;
    }
  }
 
 
  void PvlKeyword::init() {
    m_name = NULL;
    m_units = NULL;
    m_comments = NULL;
    m_width = 0;
    m_indent = 0;
    m_formatter = NULL;
 
    clear();
  }
 
  bool PvlKeyword::isNull(int index) const {
    if (size() == 0) return true;
    if (index < 0 || index >= (int)m_values.size()) {
      QString msg = Message::ArraySubscriptNotInRange(index);
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
    if (stringEqual("NULL", m_values[index])) return true;
    if (stringEqual("", m_values[index])) return true;
    if (stringEqual("\"\"", m_values[index])) return true;
    if (stringEqual("''", m_values[index])) return true;
    return false;
  }
 
  void PvlKeyword::setName(QString name) {
    QString final = name.trimmed();
    if (final.contains(QRegExp("\\s"))) {
      QString msg = "[" + name + "] is invalid. Keyword name cannot ";
      msg += "contain whitespace.";
      throw IException(IException::User, msg, _FILEINFO_);
    }
 
    if (m_name) {
      delete [] m_name;
      m_name = NULL;
    }
 
    if (final != "") {
      QByteArray finalAscii = final.toLatin1();
      m_name = new char[finalAscii.size() + 1];
      strncpy(m_name, finalAscii.data(), final.size() + 1);
    }
  }
 
  void PvlKeyword::setValue(QString value, QString unit) {
    clear();
    addValue(value, unit);
  }
 
  void PvlKeyword::setJsonValue(json jsonobj, QString unit)
  {
    clear();
    addJsonValue(jsonobj, unit);
  }
 
  void PvlKeyword::setUnits(QString units) {
    if (!m_units) {
      m_units = new std::vector<QString>();
    }
 
    m_units->clear();
 
    for (int i = 0; i < m_values.size(); i++) {
      m_units->push_back(units);
    }
  }
 
 
  void PvlKeyword::setUnits(QString value, QString units) {
 
    bool found = false;
    int i = -1;
    while(!found && ++i < (int) m_values.size()) {
      if (value == m_values[i]) {
        found = true;
      }
    }
 
    if (found) {
      if (!m_units) {
        m_units = new std::vector<QString>(m_values.size());
      }
      else {
        m_units->resize(m_values.size());
      }
 
      (*m_units)[i] = units;
    }
    else {
      IString msg = "PvlKeyword::setUnits called with value [" + value +
                    "] which does not exist in this Keyword";
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
  }
 
  PvlKeyword &PvlKeyword::operator=(QString value) {
    clear();
    addValue(value);
    return *this;
  }
 
  void PvlKeyword::addValue(QString value, QString unit) {
    m_values.append(value);
 
    if (unit != "") {
      if (!m_units) {
        m_units = new std::vector<QString>(m_values.size());
      }
      else {
        m_units->resize(m_values.size());
      }
 
      (*m_units)[m_units->size() - 1] = unit;
    }
    else if (m_units) {
      m_units->push_back("");
    }
  }
 
  void PvlKeyword::addJsonValue(json jsonobj, QString unit) {
    QString value;
    if (jsonobj.is_array()) {
      QString msg = "Unable to convert " + name() + " with nested json array value into PvlKeyword";
      throw IException(IException::Unknown, msg, _FILEINFO_);
    }
    else if (jsonobj.is_number())
    {
      value = QString::number(jsonobj.get<double>(), 'g', 16);
    }
    else if (jsonobj.is_boolean())
    {
      value = QString(jsonobj.get<bool>() ? "true" : "false");
    }
    else if (jsonobj.is_null())
    {
      value = QString("Null");
    }
    else
    {
      value = QString::fromStdString(jsonobj);
    }
    addValue(value, unit);
  }
 
  PvlKeyword &PvlKeyword::operator+=(QString value) {
    addValue(value);
    return *this;
  }
 
  void PvlKeyword::clear() {
    m_values.clear();
 
    if (m_units) {
      delete m_units;
      m_units = NULL;
    }
  }
 
 
  PvlKeyword::operator QString() const {
    return operator[](0);
  }
 
 
  QString &PvlKeyword::operator[](int index) {
    if (index < 0 || index >= (int)m_values.size()) {
      QString msg = (Message::ArraySubscriptNotInRange(index)) +
                   "for Keyword [" + QString(m_name) + "]";
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
 
    return m_values[index];
  }
 
  const QString &PvlKeyword::operator[](int index) const {
    if (index < 0 || index >= (int)m_values.size()) {
      QString msg = Message::ArraySubscriptNotInRange(index);
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
    return m_values[index];
  }
 
  QString PvlKeyword::unit(int index) const {
    if (!m_units) return "";
 
    if (index < 0 || index >= (int)m_units->size()) {
      QString msg = Message::ArraySubscriptNotInRange(index);
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
    return (*m_units)[index];
  }
 
  void PvlKeyword::addComment(QString comment) {
    if (!m_comments) {
      m_comments = new std::vector<QString>();
    }
 
    if (comment.size() == 0) {
      m_comments->push_back("#");
    }
    if (comment[0] == '#') {
      m_comments->push_back(comment);
    }
    else if (comment.size() == 1) {
      m_comments->push_back("# " + comment);
    }
    else if ((comment[0] == '/') && (comment[1] == '*')) {
      m_comments->push_back(comment);
    }
    else if ((comment[0] == '/') && (comment[1] == '/')) {
      m_comments->push_back(comment);
    }
    else {
      m_comments->push_back("# " + comment);
    }
  }
 
  void PvlKeyword::addCommentWrapped(QString comment) {
    IString cmt = comment;
    IString token = cmt.Token(" ");
    while(cmt != "") {
      IString temp = token;
      token = cmt.Token(" ");
      int length = temp.size() + token.size() + 1;
      while((length < 72) && (token.size() > 0)) {
        temp += " " + token;
        token = cmt.Token(" ");
        length = temp.size() + token.size() + 1;
      }
      addComment(temp.c_str());
    }
    if (token.size() != 0) addComment(token.c_str());
  }
 
  void PvlKeyword::clearComment() {
    if (m_comments) {
      delete m_comments;
      m_comments = NULL;
    }
  }
 
  QString PvlKeyword::comment(int index) const {
    if (!m_comments) return "";
 
    if (index < 0 || index >= (int)m_comments->size()) {
      QString msg = Message::ArraySubscriptNotInRange(index);
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
    return (*m_comments)[index];
  };
 
  QString PvlKeyword::reform(const QString &value) const {
#if 0
    static bool firstTime = true;
    static bool iPVL = true;
    if (firstTime) {
      firstTime = false;
      Isis::PvlGroup &g = Isis::Preference::Preferences().findGroup(
                            "UserInterface", Isis::Pvl::Traverse);
 
      Isis::IString s = (QString) g["PvlFormat"];
      s.UpCase();
      if (s == "PVL") iPVL = false;
    }
 
    if (iPVL) return toIPvl(value);
#endif
    return toPvl(value);
  }
 
  QString PvlKeyword::toIPvl(const QString &value) const {
    QString out;
    bool upcase = true;
    bool lastlower = true;
    for (int i = 0; i < value.size(); i++) {
      if ((lastlower) && (value[i].isUpper())) upcase = true;
      if (value[i] == '_') {
        upcase = true;
      }
      else if (upcase) {
        out += value[i].toUpper();
        lastlower = false;
        upcase = false;
      }
      else {
        out += value[i].toLower();
        if (value[i].isLower()) lastlower = true;
        upcase = false;
      }
    }
    return out;
  }
 
  QString PvlKeyword::toPvl(const QString &value) const {
    QString out;
    bool lastlower = false;
    for (int i = 0; i < value.size(); i++) {
      if ((lastlower) && (value[i].isUpper())) out += "_";
      if (value[i] == '_') {
        out += "_";
        lastlower = false;
      }
      else {
        out += value[i].toUpper();
        if (value[i].isLower()) lastlower = true;
      }
    }
    return out;
  }
 
  bool PvlKeyword::stringEqual(const QString &QString1,
                               const QString &QString2) {
    Isis::IString s1(QString1);
    Isis::IString s2(QString2);
 
    s1.ConvertWhiteSpace();
    s2.ConvertWhiteSpace();
 
    s1.Remove(" _");
    s2.Remove(" _");
 
    s1.UpCase();
    s2.UpCase();
 
    if (s1 == s2) return true;
    return false;
  }
 
  bool PvlKeyword::isEquivalent(QString QString1, int index) const {
    if (index < 0 || index >= (int)m_values.size()) {
      QString msg = Message::ArraySubscriptNotInRange(index);
      throw IException(IException::Programmer, msg, _FILEINFO_);
    }
 
    return stringEqual(m_values[index], QString1);
  }
 
  PvlKeyword &PvlKeyword::operator=(Isis::PvlSequence &seq) {
    clear();
    for (int i = 0; i < seq.Size(); i++) {
      QString temp = "(";
      for (int j = 0; j < (int)seq[i].size(); j++) {
        QString val = seq[i][j];
        if (val.contains(" ")) {
          temp += "\"" + val + "\"";
        }
        else {
          temp += val;
        }
        if (j < (int) seq[i].size() - 1) temp += ", ";
      }
      temp += ")";
      this->operator+=(temp);
    }
 
    return *this;
  }
 
  ostream &PvlKeyword::writeWithWrap(std::ostream &os,
                                     const QString &textToWrite,
                                     int startColumn,
                                     PvlFormat &format) const {
 
    /*
    http://pds.jpl.nasa.gov/tools/standards-reference.shtml
 
    pds.jpl.nasa.gov/documents/sr/Chapter12.pdf
 
    Object Description Language Specification and Usage
    The following provides a complete specification for Object Description Language
    (ODL), the language used to encode data labels for the Planetary Data System
    (PDS) and other NASA data systems. This standard contains a formal definition of
    the grammar semantics of the language. PDS specific implementation notes and
    standards are referenced in separate sections.
 
    12.5.3.1 Implementation of String Values
    A text QString read in from a label is reassembled into a QString of characters.
    The way in which the QString is broken into lines in a label does not affect the
    format of the QString after it has been reassembled. The following rules are used
              when reading text QStrings: If a format effector or a sequence of
              format effectors is encountered within a text QString,
              the effector (or sequence of effectors) is replaced by a single space
              character, unless the last character is a hyphen (dash) character. Any
              spacing characters at the end of the line are removed and any spacing
              characters at the beginning of the following line are removed. This
              allows a text QString in a label to appear with the left and right
              margins set at arbitrary points without changing the QString value. For
                       example, the following two QStrings are the same: "To be or
                       not to be" and
                       "To be or
                       not to be"
              If the last character on a line prior to a format effector is a hyphen
              (dash) character, the hyphen is removed with any spacing characters at
              the beginning of the following line. This follows the standard
              convention in English of using a hyphen to break a word across lines.
              For example, the following two QStrings are the same:
                        "The planet Jupiter is very big" and
                       "The planet Jupi-
                       ter is very big"
              Control codes, other than the horizontal tabulation character and
              format effectors, appearing within a text QString are removed.
        */
 
    /*
      We will be adding a condition for human-readable purposes:
        If a quoted QString of text does not fit on the current line,
        but will fit on the next line, use the next line.
    */
 
    // Position set
    QString remainingText = textToWrite;
    int spaceForText = format.charLimit() - 1 - format.formatEOL().length() - startColumn;
 
    // indexOf quote positions to better determine which line to put the
    //  QString on. Data structure: vector< startPos, endPos > where
    //  remainingText[startPos] and remainingText[endPos] must both be quotes.
    vector< pair<int, int> > quotedAreas;
    int  quoteStart = -1;
 
    // if its an array, indent subsequent lines 1 more
    if (textToWrite.count() > 0 && (textToWrite[0] == '(' || textToWrite[0] == '"')) {
      startColumn ++;
    }
 
    /* Standard 12.3.3.1 ->
      A quoted text QString may not contain the quotation mark, which is reserved
      to be the text QString delimiter.
 
      So we don't have to worry about escaped quotes.
    */
 
    vector< pair<char, char> > quoteStartEnds;
    quoteStartEnds.push_back(pair<char, char>('"', '"'));
    quoteStartEnds.push_back(pair<char, char>('\'', '\''));
    quoteStartEnds.push_back(pair<char, char>('<', '>'));
 
    // clean up any EOL characters, they mustn't interfere, remove sections of
    //   multiple spaces (make them into one), and indexOf quoted areas
    for (int pos = 0; pos < remainingText.size(); pos++) {
      // remove \r and \n from QString
      if (remainingText[pos] == '\n' || remainingText[pos] == '\r') {
        if (pos != remainingText.size() - 1) {
          remainingText = remainingText.mid(0, pos) +
                          remainingText.mid(pos + 1);
        }
        else {
          remainingText = remainingText.mid(0, pos);
        }
      }
 
      // convert "      " to " " if not quoted
      if (quoteStart == -1) {
        while(pos > 0 &&
              remainingText[pos-1] == ' ' &&
              remainingText[pos] == ' ') {
          remainingText = remainingText.mid(0, pos) +
                          remainingText.mid(pos + 1);
        }
      }
 
      // Find quotes
      for (unsigned int i = 0;
          (quoteStart < 0) && i < quoteStartEnds.size();
          i++) {
        if (quoteStartEnds[i].first == remainingText[pos]) {
          quoteStart = pos;
        }
      }
 
 
      //bool mismatchQuote = false;
 
      // Check to see if we're ending a quote if we didn't just
      //   start the quote and we are inside a quote
      if (quoteStart != (int)pos && quoteStart != -1) {
        for (unsigned int i = 0; i < quoteStartEnds.size(); i++) {
          if (quoteStartEnds[i].second == remainingText[pos]) {
            if (quoteStartEnds[i].first != remainingText[quoteStart]) {
              continue;
              //  mismatchQuote = true;
            }
 
            quotedAreas.push_back(pair<int, int>(quoteStart, pos));
 
            quoteStart = -1;
          }
        }
      }
 
      //if (mismatchQuote) {
      //  IString msg = "Pvl keyword values [" + textToWrite +
      //    "] can not have embedded quotes";
      //  throw iException::Message(iException::Programmer, msg, _FILEINFO_);
      //}
    }
 
    int charsLeft = spaceForText;
    int printedSoFar = 0;
 
    // while we have something to write, keep going
    while(!remainingText.isEmpty()) {
      // search backwards for the last space or comma *in the limit* (80 chars)
      int lastSpacePosition = charsLeft;
 
      // if everything fits into our remaining space, consider the last
      //   spot in the QString to be printed still the split position.
      if (lastSpacePosition >= (int)remainingText.length()) {
        lastSpacePosition = remainingText.length();
      }
      else {
        // Everything does not fit; use good space for mediocre splits (inside
        //  quoted QStrings), and excellent space for good splits (between array
        //  values for example)
        int goodSpace = -1;
        int excellentSpace = -1;
        int searchPosition = lastSpacePosition;
        bool doneSearching = false;
 
        while(!doneSearching) {
          bool currentPosQuoted = false;
 
          for (unsigned int i = 0; i < quotedAreas.size(); i++) {
            if (searchPosition + printedSoFar >= quotedAreas[i].first &&
                searchPosition + printedSoFar <= quotedAreas[i].second) {
              currentPosQuoted = true;
            }
          }
 
          if (remainingText[searchPosition] == ' ') {
            bool validSpace = true;
 
            // this really isn't a good space if the previous character is a
            // '-' though - then it would be read wrong when re-imported.
            if (searchPosition > 0 && remainingText[searchPosition - 1] == '-') {
              validSpace = false;
            }
 
            if (validSpace && goodSpace < 0) {
              goodSpace = searchPosition;
            }
 
            // An excellent space is the prefential break - not quoted and
            //   not units next.
            // we were already done if we had an excellent space
            if (validSpace && !currentPosQuoted) {
              if ((int)searchPosition < (int)(remainingText.size() - 1) &&
                  remainingText[searchPosition+1] != '<') {
                excellentSpace = searchPosition;
              }
            }
          }
 
          doneSearching = (excellentSpace >= 0 || searchPosition <= 1);
          searchPosition --;
        }
 
        // Use the best breaking point we have
        if (excellentSpace > 0) {
          lastSpacePosition = excellentSpace;
        }
        else if (goodSpace > 0) {
          lastSpacePosition = goodSpace;
        }
        else {
          lastSpacePosition = -1;
        }
      }
 
      // we found a space or comma in our limit, write to that chatacter
      //   and repeat the loop
      if (lastSpacePosition >= 0) {
        os << remainingText.mid(0, lastSpacePosition);
 
        remainingText = remainingText.mid(lastSpacePosition);
        printedSoFar += lastSpacePosition;
      }
      // we failed to indexOf a space or a comma in our limit,
      //   use a hyphen (-)
      else {
        // Make sure we don't break on "//" since Isis thinks that is a comment
        if (remainingText.mid(charsLeft-1, 2) == "//") {
          os << remainingText.mid(0, charsLeft - 2);
          os << "-";
          remainingText = remainingText.mid(charsLeft - 2);
          printedSoFar += charsLeft - 2;
        }
        else {
          os << remainingText.mid(0, charsLeft - 1);
          os << "-";
          remainingText = remainingText.mid(charsLeft - 1);
          printedSoFar += charsLeft - 1;
        }
      }
 
      // we wrote as much as possible, do a newline and repeat
      if (!remainingText.isEmpty()) {
        os << format.formatEOL();
        writeSpaces(os, startColumn);
 
        // dont allow spaces to begin the next line inside what we're printing
        if (remainingText[0] == ' ') {
          remainingText = remainingText.mid(1);
          printedSoFar += 1;
        }
      }
 
      charsLeft = spaceForText;
    }
 
    return os;
  }
 
 
  void PvlKeyword::writeSpaces(std::ostream &os, int numSpaces) const {
    for (int space = 0; space < numSpaces; space ++) {
      os << " ";
    }
  }
 
 
  void PvlKeyword::setFormat(PvlFormat *formatter) {
    m_formatter = formatter;
  }
 
 
  PvlFormat *PvlKeyword::format() {
    return m_formatter;
  };
 
  std::istream &operator>>(std::istream &is, PvlKeyword &result) {
    result = PvlKeyword();
    QString line;
    QString keywordString;
 
    bool keywordDone = false;
    bool multiLineComment = false;
    bool error = !is.good();
 
    while(!error && !keywordDone) {
      istream::pos_type beforeLine = is.tellg();
 
      line = PvlKeyword::readLine(is, multiLineComment);
 
      // We read an empty line (failed to read next non-empty line)
      // and didnt complete our keyword, essentially we hit the implicit
      // keyword named "End"
      if (line.isEmpty() && !is.good()) {
        if (keywordString.isEmpty() ||
            keywordString[keywordString.size()-1] == '\n') {
          line = "End";
 
          if (multiLineComment) {
            error = true;
          }
        }
        else {
          error = true;
        }
      }
 
      bool comment = false;
 
      if (!multiLineComment) {
        if (line.size() > 0 && line[0] == '#') {
          comment = true;
        }
 
        if (line.size() > 1 && line[0] == '/' &&
            (line[1] == '*' || line[1] == '/')) {
          comment = true;
 
          if (line[1] == '*') {
            multiLineComment = true;
            keywordString += line.mid(0, 2);
            line = line.mid(2).trimmed();
          }
        }
      }
 
      if (multiLineComment) {
        comment = true;
 
        if (line.contains("/*")) {
          IString msg = "Error when reading a pvl: Cannot have ['/*'] inside a "
                        "multi-line comment";
          throw IException(IException::Unknown, msg, _FILEINFO_);
        }
 
        if (line.contains("*/")) {
          multiLineComment = false;
 
          line = line.mid(0, line.indexOf("*/")).trimmed() + " */";
        }
      }
 
      if (line.isEmpty()) {
        continue;
      }
      // comment line
      else if (comment) {
        keywordString += line + '\n';
        continue;
      }
      // first line of keyword data
      else if (keywordString.isEmpty()) {
        keywordString = line;
      }
      // concatenation
      else if (!comment && keywordString[keywordString.size()-1] == '-') {
        keywordString = keywordString.mid(0, keywordString.size() - 1) + line;
      }
      // Non-commented and non-concatenation -> put in the space
      else {
        keywordString += " " + line;
      }
      // if this line concatenates with the next, read the next
      if (line[line.size()-1] == '-') {
        continue;
      }
 
      std::vector<QString> keywordComments;
      QString keywordName;
      std::vector< std::pair<QString, QString> > keywordValues;
 
      bool attemptedRead = false;
 
      try {
        attemptedRead = PvlKeyword::readCleanKeyword(keywordString,
                        keywordComments,
                        keywordName,
                        keywordValues);
      }
      catch (IException &e) {
        if (is.eof() && !is.bad()) {
          is.clear();
          is.unget();
        }
 
        is.seekg(beforeLine, ios::beg);
 
        QString msg = "Unable to read PVL keyword [";
        msg += keywordString;
        msg += "]";
 
        throw IException(e, IException::Unknown, msg, _FILEINFO_);
      }
 
      // Result valid?
      if (attemptedRead) {
        // if the next line starts with '<' then it should be read too...
        // it should be units
        // however, you can't have units if there is no value
        if (is.good() && is.peek() == '<' && !keywordValues.empty()) {
          continue;
        }
 
        result.setName(keywordName);
        result.addComments(keywordComments);
 
        for (unsigned int value = 0; value < keywordValues.size(); value++) {
          result.addValue(keywordValues[value].first,
                          keywordValues[value].second);
        }
 
        keywordDone = true;
      }
 
      if (!attemptedRead) {
        error = error || !is.good();
      }
      // else we need to keep reading
    }
 
    if (error) {
      // skip comments
      while(keywordString.contains('\n')) {
        keywordString = keywordString.mid(keywordString.indexOf('\n') + 1);
      }
 
      QString msg;
 
      if (keywordString.isEmpty() && !multiLineComment) {
        msg = "PVL input contains no Pvl Keywords";
      }
      else if (multiLineComment) {
        msg = "PVL input ends while still in a multi-line comment";
      }
      else {
        msg = "The PVL keyword [" + keywordString + "] does not appear to be";
        msg += " a valid Pvl Keyword";
      }
 
      throw IException(IException::Unknown, msg, _FILEINFO_);
    }
 
    if (!keywordDone) {
      // skip comments
      while(keywordString.contains('\n'))
        keywordString = keywordString.mid(keywordString.indexOf('\n') + 1);
 
      QString msg;
 
      if (keywordString.isEmpty()) {
        msg = "Error reading PVL keyword";
      }
      else {
        msg = "The PVL keyword [" + keywordString + "] does not appear to be";
        msg += " complete";
      }
 
      throw IException(IException::Unknown, msg, _FILEINFO_);
    }
 
    return is;
  }
 
  void PvlKeyword::addComments(const std::vector<QString> &comments) {
    for (unsigned int i = 0; i < comments.size(); i++) {
      addComment(comments[i]);
    }
  }
 
  bool PvlKeyword::readCleanKeyword(QString keyword,
                                    std::vector<QString> &keywordComments,
                                    QString &keywordName,
                                    std::vector< std::pair<QString, QString> > &keywordValues) {
    // Reset outputs
    keywordComments.clear();
    keywordName = "";
    keywordValues.clear();
 
    // This is in case a close quote doesn't exist
    bool explicitIncomplete = false;
 
    // Possible (known) comment starts in pvl
    QString comments[] = {
      "#",
      "//"
    };
 
    // Need more data if nothing is here!
    if (keyword.isEmpty()) return 0;
 
    /*
      Step 1: Read Comments
 
      Theoretically, we should have an input that looks like this:
        #Comment
        //Comment
        / * Comment
            Comment * /
        Keyword = Data
 
      So we could just grab all of the first lines; however, this method
      needs to be as error-proof as possible (it is the basis of reading
      all PVLs after all), so verify we have things that look like comments
      first, strip them & store them.
     */
 
    // While we have newlines, we have comments
    while(keyword.contains("\n")) {
      // Make sure we strip data every loop of comment types; otherwise we
      // have no comment and need to error out.
      bool noneStripped = true;
 
      // Check every comment type now and make sure this line (it isn't the last
      // line since a newline exists) starts in a comment
      QString keywordStart = keyword.mid(0, 2);
 
      // Handle multi-line comments
      if (keywordStart == "/*") {
        noneStripped = false;
        bool inComment = true;
 
        while(inComment && keyword.contains("*/")) {
          // Correct the */ to make sure it has a \n after it,
          // without this we risk an infinite loop
          int closePos = keyword.indexOf("*/\n");
 
          if (closePos == -1) {
            closePos = keyword.indexOf("*/") + 2;
            keyword = keyword.mid(0, closePos) + "\n" +
                      keyword.mid(closePos);
          }
 
          QString comment = keyword.mid(0, keyword.indexOf("\n")).trimmed();
 
          // Set these to true if too small, false if not (they need if
          //   cant currently fit).
          bool needsStart = (comment.size() < 2);
          bool needsStartSpace = comment.size() < 3;
 
          int commentEndPos = comment.size() - 2;
          bool needsEnd = (commentEndPos < 0);
          bool needsEndSpace = comment.size() < 3;
 
          // Needs are currently set based on QString size, apply real logic
          //   to test for character sequences (try to convert them from false
          //   to true).
          if (!needsStart) {
            needsStart = (comment.mid(0, 2) != "/*");
          }
 
          if (!needsEnd) {
            needsEnd = (comment.mid(commentEndPos, 2) != "*/");
          }
 
          if (!needsStartSpace) {
            needsStartSpace = (comment.mid(0, 3) != "/* ");
          }
 
          if (!needsEndSpace) {
            needsEndSpace = (comment.mid(commentEndPos - 1, 3) != " */");
          }
 
          if (needsStart) {
            comment = "/* " + comment;
          }
          else if (needsStartSpace) {
            comment = "/* " + comment.mid(2);
          }
 
          if (needsEnd) {
            comment = comment + " */";
          }
          else if (needsEndSpace) {
            comment = comment.mid(0, comment.size() - 2) + " */";;
          }
 
          inComment = needsEnd;
 
          keywordComments.push_back(comment);
 
          if (keyword.contains("\n")) {
            keyword = keyword.mid(keyword.indexOf("\n") + 1).trimmed();
          }
 
          // Check for another comment start
          if (!inComment) {
            if (keyword.size() >= 2)
              keywordStart = keyword.mid(0, 2);
 
            inComment = (keywordStart == "/*");
          }
        }
 
        // So we have a bunch of multi-line commands... make them the same size
        //   Find longest
        int longest = 0;
        for (unsigned int index = 0; index < keywordComments.size(); index++) {
          QString comment = keywordComments[index];
 
          if (comment.size() > longest)
            longest = comment.size();
        }
 
        // Now make all the sizes match longest
        for (unsigned int index = 0; index < keywordComments.size(); index++) {
          QString comment = keywordComments[index];
 
          while(comment.size() < longest) {
            // This adds a space to the end of the comment
            comment = comment.mid(0, comment.size() - 2) + " */";
          }
 
          keywordComments[index] = comment;
        }
        // They should all be the same length now
      }
 
      // Search for single line comments
      for (unsigned int commentType = 0;
          commentType < sizeof(comments) / sizeof(QString);
          commentType++) {
 
        if (keywordStart.startsWith(comments[commentType])) {
          // Found a comment start; strip this line out and store it as a
          // comment!
          QString comment = keyword.mid(0, keyword.indexOf("\n"));
          keywordComments.push_back(comment.trimmed());
 
          noneStripped = false;
 
          if (keyword.contains("\n")) {
            keyword = keyword.mid(keyword.indexOf("\n") + 1).trimmed();
          }
        }
      }
 
      // Does it look like Name=Value/*comm
      //                              mment*/ ?
      if (noneStripped && keyword.contains("/*") &&
          keyword.contains("*/")) {
        QString firstPart = keyword.mid(0, keyword.indexOf("\n"));
        QString lastPart = keyword.mid(keyword.indexOf("\n") + 1);
 
        keyword = firstPart.trimmed() + " " + lastPart.trimmed();
        noneStripped = false;
      }
 
      if (noneStripped) {
        QString msg = "Expected a comment in PVL but found [";
        msg += keyword;
        msg += "]";
        throw IException(IException::Unknown, msg, _FILEINFO_);
      }
    }
 
    // Do we have a keyword at all?
    if (keyword.isEmpty()) {
      return false; // need more data
    }
 
    /*
      Step 2: Determine Keyword Format
 
      Make sure we have a keyword after the comments first. We expect
      one of three formats:
        KEYWORD                             PROCESSED IN STEP 3.1
        KEYWORD = (VALUE,VALUE,...)         PROCESSED IN STEP 3.2
        KEYWORD = VALUE                     PROCESSED IN STEP 3.3
     */
 
    // Get the keyword name
    keywordName = readValue(keyword, explicitIncomplete);
 
    // we have taken the name; if nothing remains then it is value-less
    // and we are done.
    if (keyword.isEmpty()) {
      /*
        Step 3.1
 
        Format is determined to be:
          KEYWORD
 
        Well, no value/units may exist so we're done processing this keyword.
       */
      return 1; // Valid & Successful
    }
 
    // if we don't have an equal, then we have a problem - an invalid symbol.
    // Our possible remaining formats both are KEYWORD = ...
    if (keyword[0] != '=') {
      QString msg = "Expected an assignment [=] when reading PVL, but found [";
      msg += keyword[0];
      msg += "]";
 
      throw IException(IException::Unknown, msg, _FILEINFO_);
    }
 
    keyword = keyword.mid(1).trimmed();
 
    if (keyword.isEmpty()) {
      return false;
    }
 
    // now we need to split into two possibilities: array or non-array
    if (keyword[0] == '(' || keyword[0] == '{') {
      /*
        Step 3.2
 
        Our format is confirmed as:
          KEYWORD = (...)
 
        We need to read each value/unit in the array.
      */
 
      char closingParen = ((keyword[0] == '(') ? ')' : '}');
      char wrongClosingParen = ((keyword[0] == '(') ? '}' : ')');
      bool closedProperly = false;
 
      vector< pair<char, char> > extraDelims;
      extraDelims.push_back(pair<char, char>('(', ')'));
      extraDelims.push_back(pair<char, char>('{', '}'));
 
      // strip '(' - onetime, this makes every element in the array the same
      // (except the last)
      keyword = keyword.mid(1).trimmed();
 
      // handle empty arrays: KEYWORD = ()
      if (!keyword.isEmpty() && keyword[0] == closingParen) {
        closedProperly = true;
      }
 
      // Each iteration of this loop should consume 1 value in the array,
      // including the comma, i.e. we should start out with:
      //  'VALUE,VALUE,...)' until we hit ')' (our exit condition)
      while(!keyword.isEmpty() && keyword[0] != closingParen) {
        // foundComma delimits the end of this element in the array (remains
        //  false for last value which has no comma at the end)
        bool foundComma = false;
        // keyword should be of the format: VALUE <UNIT>,....)
        // Read VALUE from it
        QString nextItem = readValue(keyword, explicitIncomplete, extraDelims);
 
        if (!keyword.isEmpty() && keyword[0] == wrongClosingParen) {
 
          QString msg = "Incorrect array close when reading PVL; expected [";
          msg += closingParen;
          msg += "] but found [";
          msg += wrongClosingParen;
          msg += "] in keyword named [";
          msg += keywordName;
          msg += "]";
          throw IException(IException::Unknown, msg, _FILEINFO_);
        }
 
        // This contains <VALUE, UNIT>
        pair<QString, QString> keywordValue;
 
        // Store VALUE
        keywordValue.first = nextItem;
 
        // Now there's 2 possibilities: units or no units ->
        //   if we have units, read them
        if (!keyword.isEmpty() && keyword[0] == '<') {
          QString unitsValue = readValue(keyword, explicitIncomplete);
          keywordValue.second = unitsValue;
        }
 
        // Now we should* have a comma, strip it
        if (!keyword.isEmpty() && keyword[0] == ',') {
          foundComma = true;
          keyword = keyword.mid(1).trimmed();
        }
 
        // No comma and nothing more in QString - we found
        //  KEYWORD = (VALUE,VALUE\0
        //  we need more information to finish this keyword
        if (!foundComma && keyword.isEmpty()) {
          return false; // could become valid later
        }
 
        bool foundCloseParen = (!keyword.isEmpty() && keyword[0] == closingParen);
 
        if (foundCloseParen) {
          closedProperly = true;
        }
 
        // Check for the condition of:
        //  keyword = (VALUE,VALUE,)
        // which is unrecoverable
        if (foundComma && foundCloseParen) {
          QString msg = "Unexpected close of keyword-value array when reading "
                       "PVL";
          throw IException(IException::Unknown, msg, _FILEINFO_);
        }
 
        // Check for (VALUE VALUE
        if (!foundComma && !foundCloseParen) {
          // We have ("VALUE VALUE
          if (explicitIncomplete) return false;
 
          // We have (VALUE VALUE
          QString msg = "Found extra data after [";
          msg += nextItem;
          msg += "] in array when reading PVL";
          throw IException(IException::Unknown, msg, _FILEINFO_);
        }
 
        // we're good with this element of the array, remember it
        keywordValues.push_back(keywordValue);
      }
 
      if (!closedProperly) {
        return false;
      }
 
      // Trim off the closing paren
      if (!keyword.isEmpty()) {
        keyword = keyword.mid(1).trimmed();
      }
 
      // Read units here if they exist and apply them
      //  case: (A,B,C) <unit>
      if (!keyword.isEmpty() && keyword[0] == '<') {
        QString units = readValue(keyword, explicitIncomplete);
        for (unsigned int val = 0; val < keywordValues.size(); val++) {
          if (keywordValues[val].second.isEmpty()) {
            keywordValues[val].second = units;
          }
        }
      }
    }
    else {
      /*
        Step 3.3
 
        Our format is confirmed as:
          "KEYWORD = VALUE <UNIT>"
 
        We need to read the single value/unit in the keywordValues array.
       */
      pair<QString, QString> keywordValue;
      keywordValue.first = readValue(keyword, explicitIncomplete);
 
      if (!keyword.isEmpty() && keyword[0] == '<') {
        keywordValue.second = readValue(keyword, explicitIncomplete);
      }
 
      keywordValues.push_back(keywordValue);
    }
 
    /*
      This is set when a quote is opened somewhere and never closed, it means
      we need more information
     */
    if (explicitIncomplete) {
      return false; // unclosed quote at end... need more information
    }
 
    /*
      See if we have a comment at the end of the keyword...
     */
    if (!keyword.isEmpty()) {
      // if the data left is a comment, we can handle it probably
      if (keyword[0] == '#' ||
          ((keyword.size() > 1 && keyword[0] == '/') &&
           (keyword[1] == '/' || keyword[1] == '*'))) {
        keywordComments.push_back(keyword);
 
        if (keyword.size() > 1 && keyword.mid(0, 2) == "/*") {
          if (keyword.mid(keyword.size() - 2, 2) != "*/")
            return false; // need more comment data
        }
 
        keyword = "";
      }
    }
 
    // check for extraneous data in the keyword ... ,2,3
    QRegularExpression regex("^,");
    QRegularExpressionMatch match = regex.match(keyword);
    if (!keyword.isEmpty() && match.hasMatch()) {
          keywordValues.at(0).first += keyword;
          keyword = "";
    }
 
    /*
      If more data remains, it is unrecognized.
    */
    if (!keyword.isEmpty()) {
      QString msg = "Keyword has extraneous data [";
      msg += keyword;
      msg += "] at the end";
      throw IException(IException::Unknown, msg, _FILEINFO_);
    }
 
    // We've parsed this keyword! :)
    return true;
  }
 
 
  QString PvlKeyword::readValue(QString &keyword, bool &quoteProblem) {
    std::vector< std::pair<char, char> > otherDelims;
 
    return readValue(keyword, quoteProblem, otherDelims);
  }
 
  QString PvlKeyword::readValue(QString &keyword, bool &quoteProblem,
                                    const std::vector< std::pair<char, char> > &
                                    otherDelimiters) {
    QString value = "";
 
    // This method ignores spaces except as delimiters; let's trim the QString
    // to start
    keyword = keyword.trimmed();
 
    if (keyword.isEmpty()) {
      return "";
    }
 
    // An implied quote is one that is started without a special character, for
    //  example HELLO WORLD has HELLO and WORLD separately as implied quotes for
    //  PVLs. However, "HELLO WORLD" has an explicit (not implied) double quote.
    //  We do consider <> as quotes.
    bool impliedQuote = true;
    QChar quoteEnd = ' ';
    bool keepQuotes = false;
 
    if (keyword[0] == '\'' || keyword[0] == '"') {
      quoteEnd = keyword[0];
      impliedQuote = false;
    }
    else if (keyword[0] == '<') {
      quoteEnd = '>';
      impliedQuote = false;
    }
    else {
      // we're not quoted, look for alternative delimiters.
      char implicitQuotes[] = {
        ')',
        '}',
        ',',
        ' ',
        '\t',
        '<',
        '='
      };
 
      bool foundImplicitQuote = false;
 
      int currentPos = 0;
      while(!foundImplicitQuote && currentPos != keyword.size()) {
        for (unsigned int quote = 0;
            quote < sizeof(implicitQuotes) / sizeof(char);
            quote ++) {
          if (keyword[currentPos] == implicitQuotes[quote]) {
            quoteEnd = implicitQuotes[quote];
            foundImplicitQuote = true;
          }
        }
 
        if (!foundImplicitQuote) {
          currentPos ++;
        }
      }
    }
 
    for (unsigned int delim = 0; delim < otherDelimiters.size(); delim ++) {
      if (keyword[0] == otherDelimiters[delim].first) {
        quoteEnd = otherDelimiters[delim].second;
        keepQuotes = true;
        impliedQuote = false;
      }
    }
 
    QString startQuote;
    // non-implied delimeters need the opening delimiter ignored. Remember
    //  startQuote in case of error later on we can reconstruct the original
    //  QString.
    if (!impliedQuote) {
      startQuote += keyword[0];
      keyword = keyword.mid(1);
    }
 
    // Do we have a known quote end?
    int quoteEndPos = keyword.indexOf(quoteEnd);
 
    if (quoteEndPos != -1) {
      value = keyword.mid(0, quoteEndPos);
 
      // Trim keyword 1 past end delimiter (if end delimiter is last, this
      // results in empty QString). If the close delimiter is ')' or ',' then
      // leave it be however, since we need to preserve that to denote this was
      //  an end of a valuein array keyword.
      if (!impliedQuote) {
        keyword = keyword.mid(quoteEndPos + 1);
      }
      else {
        keyword = keyword.mid(quoteEndPos);
      }
 
      // Make sure we dont have padding
      keyword = keyword.trimmed();
 
      if (keepQuotes) {
        value = startQuote + value + quoteEnd;
      }
 
      return value;
    }
    // implied quotes terminate at end of keyword; otherwise we have a problem
    //   (which is this condition)
    else if (!impliedQuote) {
      // restore the original QString
      keyword = startQuote + keyword;
      quoteProblem = true;
 
      return "";
    }
 
    // we have an implied quote but no quote character, the rest must be the
    //  value.
    value = keyword;
    keyword = "";
 
    return value;
  }
 
 
  QString PvlKeyword::readLine(std::istream &is, bool insideComment) {
    QString lineOfData;
 
    while(is.good() && lineOfData.isEmpty()) {
 
      // read until \n (works for both \r\n and \n) or */
      while(is.good() &&
            (!lineOfData.size() || lineOfData[lineOfData.size() - 1] != '\n')) {
        char next = is.get();
 
        // if non-ascii found then we're done... immediately
        if (next <= 0) {
          is.seekg(0, ios::end);
          is.get();
          return lineOfData;
        }
 
        // if any errors (i.e. eof) happen in the get operation then don't
        //   store this data
        if (is.good()) {
          lineOfData += next;
        }
 
        if (insideComment &&
            lineOfData.size() >= 2 && lineOfData[lineOfData.size() - 2] == '*' &&
            lineOfData[lineOfData.size() - 1] == '/') {
          // End of multi-line comment = end of line!
          break;
        }
        else if (lineOfData.size() >= 2 &&
                lineOfData[lineOfData.size() - 2] == '/' &&
                lineOfData[lineOfData.size() - 1] == '*') {
          insideComment = true;
        }
      }
 
      // Trim off non-visible characters from this line of data
      lineOfData = lineOfData.trimmed();
 
      // read up to next non-whitespace in input stream
      while(is.good() &&
            (is.peek() == ' ' ||
             is.peek() == '\r' ||
             is.peek() == '\n')) {
        is.get();
      }
 
      // if lineOfData is empty (line was empty), we repeat
    }
 
    return lineOfData;
  }
 
 
  ostream &operator<<(std::ostream &os, const Isis::PvlKeyword &keyword) {
    // Set up a Formatter
    PvlFormat *tempFormat = keyword.m_formatter;
    bool removeFormatter = false;
    if (tempFormat == NULL) {
      tempFormat = new PvlFormat();
      removeFormatter = true;
    }
 
    // Write out the comments
    for (int i = 0; i < keyword.comments(); i++) {
      for (int j = 0; j < keyword.indent(); j++) os << " ";
      os << keyword.comment(i) << tempFormat->formatEOL();
    }
 
    // Write the keyword name & add length to startColumn.
    int startColumn = 0;
    for (int i = 0; i < keyword.indent(); i++) {
      os << " ";
      ++startColumn;
    }
    QString keyname = tempFormat->formatName(keyword);
    os << keyname;
    startColumn += keyname.length();
 
    // Add padding and then write equal sign.
    for (int i = 0; i < keyword.width() - (int)keyname.size(); ++i) {
      os << " ";
      ++startColumn;
    }
    os << " = ";
    startColumn += 3;
 
    // If it has no value then write a NULL
    if (keyword.size() == 0) {
      os << tempFormat->formatValue(keyword);
    }
 
    // Loop and write each array value
    QString stringToWrite;
    for (int i = 0; i < keyword.size(); i ++) {
      stringToWrite += tempFormat->formatValue(keyword, i);
    }
 
    keyword.writeWithWrap(os,
                          stringToWrite,
                          startColumn,
                          *tempFormat);
 
    if (removeFormatter) delete tempFormat;
 
    return os;
  }
 
 
  const PvlKeyword &PvlKeyword::operator=(const PvlKeyword &other) {
    if (this != &other) {
      m_formatter = other.m_formatter;
 
      if (m_name) {
        delete [] m_name;
        m_name = NULL;
      }
 
      if (other.m_name) {
        setName(other.m_name);
      }
 
      m_values = other.m_values;
 
      if (m_units) {
        delete m_units;
        m_units = NULL;
      }
 
      if (other.m_units) {
        m_units = new std::vector<QString>(*other.m_units);
      }
 
      if (m_comments) {
        delete m_comments;
        m_comments = NULL;
      }
 
      if (other.m_comments) {
        m_comments = new std::vector<QString>(*other.m_comments);
      }
 
      m_width = other.m_width;
      m_indent = other.m_indent;
    }
 
    return *this;
  }
 
  void PvlKeyword::validateKeyword(PvlKeyword & pvlKwrd, QString psValueType, PvlKeyword* pvlKwrdValue)
  {
    int iSize = pvlKwrd.size();
 
    QString sType = m_values[0].toLower();
 
    // Value type
    if (psValueType.length()) {
      psValueType = psValueType.toLower();
    }
 
    double dRangeMin=0, dRangeMax=0;
    bool bRange = false;
    bool bValue = false;
    if (pvlKwrdValue != NULL) {
      QString sValueName = pvlKwrdValue->name();
 
      // Check for Range
      if (sValueName.contains("__Range")) {
        dRangeMin = toDouble((*pvlKwrdValue)[0]);
        dRangeMax = toDouble((*pvlKwrdValue)[1]);
        bRange = true;
      }
      else if (sValueName.contains("__Value")) {
        bValue = true;
      }
    }
 
    // Type integer
    if (sType == "integer") {
      for (int i=0; i<iSize; i++) {
        QString sValue = pvlKwrd[i].toLower();
        if (sValue != "null"){
          int iValue=0;
          try {
            iValue = toInt(sValue);
          } catch (IException & e) {
            QString sErrMsg = "\"" +pvlKwrd.name() +"\" expects an Integer value";
            throw IException(e, IException::User, sErrMsg, _FILEINFO_);
          }
          if (bRange && (iValue < dRangeMin || iValue > dRangeMax)) {
            QString sErrMsg = "\"" +pvlKwrd.name() +"\" is not in the specified Range";
            throw IException(IException::User, sErrMsg, _FILEINFO_);
          }
          if (bValue) {
            bool bFound = false;
            for (int j=0; j<pvlKwrdValue->size(); j++) {
              if (iValue == toInt((*pvlKwrdValue)[j])) {
                bFound = true;
                break;
              }
            }
            if (!bFound) {
              QString sErrMsg = "\"" +pvlKwrd.name() +"\" has value not in the accepted list";
              throw IException(IException::User, sErrMsg, _FILEINFO_);
            }
          }
          // Type is specified (positive / negative)
          if (psValueType.length()) {
            if ((psValueType == "positive" && iValue < 0) || (psValueType == "negative" && iValue >= 0) ) {
              QString sErrMsg = "\"" +pvlKwrd.name() +"\" has invalid value";
              throw IException(IException::User, sErrMsg, _FILEINFO_);
            }
          }
        }
      }
      return;
    }
 
    // Type double
    if (sType == "double") {
      for (int i=0; i<iSize; i++) {
        QString sValue = pvlKwrd[i].toLower();
        if (sValue != "null"){
          double dValue = toDouble(sValue);
          if (bRange && (dValue < dRangeMin || dValue > dRangeMax)) {
            QString sErrMsg = "\"" +pvlKwrd.name() +"\" is not in the specified Range";
            throw IException(IException::User, sErrMsg, _FILEINFO_);
          }
          if (bValue) {
            bool bFound = false;
            for (int j=0; j<pvlKwrdValue->size(); j++) {
              if (dValue == toDouble((*pvlKwrdValue)[j])) {
                bFound = true;
                break;
              }
            }
            if (!bFound) {
              QString sErrMsg = "\"" +pvlKwrd.name() +"\" has value not in the accepted list";
              throw IException(IException::User, sErrMsg, _FILEINFO_);
            }
          }
          // Type is specified (positive / negative)
          if (psValueType.length()) {
            if ((psValueType == "positive" && dValue < 0) || (psValueType == "negative" && dValue >= 0) ) {
              QString sErrMsg = "\"" +pvlKwrd.name() +"\" has invalid value";
              throw IException(IException::User, sErrMsg, _FILEINFO_);
            }
          }
        }
      }
      return;
    }
 
    // Type boolean
    if (sType == "boolean") {
      for (int i=0; i<iSize; i++) {
        QString sValue = pvlKwrd[i].toLower();
        if (sValue != "null" && sValue != "true" && sValue != "false"){
          QString sErrMsg = "Wrong Type of value in the Keyword \"" + name() + "\" \n";
          throw IException(IException::User, sErrMsg, _FILEINFO_);
        }
      }
      return;
    }
 
    // Type String
    if (sType == "string") {
      for (int i=0; i<iSize; i++) {
        QString sValue = pvlKwrd[i].toLower();
        if (bValue) {
          bool bValFound = false;
          for (int i=0; i<pvlKwrdValue->size(); i++) {
            if (sValue == (*pvlKwrdValue)[i].toLower()) {
              bValFound = true;
              break;
            }
          }
          if (!bValFound) {
            QString sErrMsg = "Wrong Type of value in the Keyword \"" + name() + "\" \n";
            throw IException(IException::User, sErrMsg, _FILEINFO_);
          }
        }
      }
    }
  }
}