#include "Util.hpp"

#include <QRegularExpression>

namespace Util {
    QString trimQuotes(QString string, bool& trimmed)
    {
        if(string.isEmpty()) return string;

        trimmed = false;
        if(string.length() >= 2 && string.at(0) == '"' && string.at(string.length() - 1) == '"')
        {
            string.remove(0, 1);
            string.remove(string.length() - 1, 1);
            trimmed = true;
        }
        return string;
    }

    QString unescape(const QString &string, const QChar escapeChar)
    {
        if(string.isEmpty()) return string;
        QString ret;
        bool escaped = false;
        QChar c = string.at(0);
        for(int i = 0; i < string.length(); ++i)
        {
            c = string.at(i);
            if(!escaped)
            {
                if(c == escapeChar)
                {
                    escaped = true;
                    continue;
                }
                else
                {
                    ret.append(c);
                }
            }
            else
            {
                if(unescapeChars.contains(c))
                {
                    ret.append(unescapeChars.value(c));
                }
                else
                {
                    ret.append(c);
                }
                escaped = false;
            }
        }
        if(escaped)
        {
            ret.append(escapeChar);
        }
        return ret;
    }

    QString escape(const QString &string, const QChar escapeChar, const QString &escapeChars)
    {
        QString ret;

        for(int i = 0; i < string.length(); ++i)
        {
            QChar c = string.at(i);

            if(c == escapeChar)
            {
                ret.append(escapeChar);
                ret.append(escapeChar);
            }
            else if(escapeChars.contains(c))
            {
                ret.append(escapeChar);
                ret.append(c);
            }
            else if(unescapeChars.values().contains(c))
            {
                ret.append(unescapeChars.key(c));
            }
            else
            {
                ret.append(c);
            }
        }

        return ret;
    }

    QString joinEscape(const QStringList &list, const QChar joinChar, const QChar escapeChar)
    {
        QString ret;
        bool first = true;
        foreach(const QString& part, list)
        {
            if(!first)
            {
                ret.append(joinChar);
            }
            else
            {
                first = false;
            }
            ret.append(escape(part, escapeChar, joinChar));
        }
        return ret;
    }

    QStringList splitEscaped(const QString &joined, const QChar splitChar, const QChar escapeChar)
    {
        QStringList ret;

        int partPos = 0;
        bool escaped = false;
        for(int i = 0; i < joined.length(); ++i)
        {
            QChar c = joined.at(i);
            if(!escaped)
            {
                if(c == escapeChar)
                {
                    escaped = true;
                }
                else if(c == splitChar)
                {
                    ret.append(Util::unescape(joined.mid(partPos, i - partPos), escapeChar));
                    partPos = i + 1;
                }
            }
            else
            {
                escaped = false;
            }
        }
        ret.append(Util::unescape(joined.mid(partPos), escapeChar));

        return ret;
    }

    QString& unescapeClonkString(QString&& string)
    {
        static QRegularExpression escapeExp(R"(\\[0-7]+)");
        QRegularExpressionMatch match;
        while((match = escapeExp.match(string)).hasMatch())
        {
            unsigned char c = (unsigned char)match.capturedRef(0).mid(1).toInt(0, 8);

            string.replace(match.capturedStart(), match.capturedLength(), c);
        }
        return string;
    }

    int indexOfEscaped(const QString& string, const QChar subject, int startPos, const QChar escapeChar)
    {
        if(string.isEmpty())
        {
            return -1;
        }
        if(startPos < 0)
        {
            startPos += string.length();
        }
        bool escaped = false;
        for(int pos = startPos; pos < string.length(); ++pos)
        {
            QChar c = string.at(pos);
            if(!escaped)
            {
                if(c == escapeChar)
                {
                    escaped = true;
                    continue;
                }
                else
                {
                    if(c == subject)
                    {
                        return pos;
                    }
                }
            }
            else
            {
                escaped = false;
            }
        }
        return -1;
    }
}