/*
 * Copyright (C) 2004-2020 ZNC, see the NOTICE file for details.
 *
 * 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.
 */

#include <znc/ZNCString.h>
#include <znc/FileUtils.h>
#include <znc/Utils.h>
#include <znc/MD5.h>
#include <znc/SHA256.h>
#include <sstream>

using std::stringstream;

CString::CString(char c) : string() {
    stringstream s;
    s << c;
    *this = s.str();
}
CString::CString(unsigned char c) : string() {
    stringstream s;
    s << c;
    *this = s.str();
}
CString::CString(short i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(unsigned short i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(int i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(unsigned int i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(long i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(unsigned long i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(long long i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(unsigned long long i) : string() {
    stringstream s;
    s << i;
    *this = s.str();
}
CString::CString(double i, int precision) : string() {
    stringstream s;
    s.precision(precision);
    s << std::fixed << i;
    *this = s.str();
}
CString::CString(float i, int precision) : string() {
    stringstream s;
    s.precision(precision);
    s << std::fixed << i;
    *this = s.str();
}

unsigned char* CString::strnchr(const unsigned char* src, unsigned char c,
                                unsigned int iMaxBytes, unsigned char* pFill,
                                unsigned int* piCount) const {
    for (unsigned int a = 0; a < iMaxBytes && *src; a++, src++) {
        if (pFill) {
            pFill[a] = *src;
        }

        if (*src == c) {
            if (pFill) {
                pFill[a + 1] = 0;
            }

            if (piCount) {
                *piCount = a;
            }

            return (unsigned char*)src;
        }
    }

    if (pFill) {
        *pFill = 0;
    }

    if (piCount) {
        *piCount = 0;
    }

    return nullptr;
}

int CString::CaseCmp(const CString& s, CString::size_type uLen) const {
    if (uLen != CString::npos) {
        return strncasecmp(c_str(), s.c_str(), uLen);
    }
    return strcasecmp(c_str(), s.c_str());
}

int CString::StrCmp(const CString& s, CString::size_type uLen) const {
    if (uLen != CString::npos) {
        return strncmp(c_str(), s.c_str(), uLen);
    }
    return strcmp(c_str(), s.c_str());
}

bool CString::Equals(const CString& s, CaseSensitivity cs) const {
    if (cs == CaseSensitive) {
        return (StrCmp(s) == 0);
    } else {
        return (CaseCmp(s) == 0);
    }
}

bool CString::Equals(const CString& s, bool bCaseSensitive,
                     CString::size_type uLen) const {
    if (bCaseSensitive) {
        return (StrCmp(s, uLen) == 0);
    } else {
        return (CaseCmp(s, uLen) == 0);
    }
}

bool CString::WildCmp(const CString& sWild, const CString& sString,
                      CaseSensitivity cs) {
    // avoid a copy when cs == CaseSensitive (C++ deliberately specifies that
    // binding a temporary object to a reference to const on the stack
    // lengthens the lifetime of the temporary to the lifetime of the reference
    // itself)
    const CString& sWld = (cs == CaseSensitive ? sWild : sWild.AsLower());
    const CString& sStr = (cs == CaseSensitive ? sString : sString.AsLower());

    // Written by Jack Handy - jakkhandy@hotmail.com
    const char* wild = sWld.c_str(), *CString = sStr.c_str();
    const char* cp = nullptr, *mp = nullptr;

    while ((*CString) && (*wild != '*')) {
        if ((*wild != *CString) && (*wild != '?')) {
            return false;
        }

        wild++;
        CString++;
    }

    while (*CString) {
        if (*wild == '*') {
            if (!*++wild) {
                return true;
            }

            mp = wild;
            cp = CString + 1;
        } else if ((*wild == *CString) || (*wild == '?')) {
            wild++;
            CString++;
        } else {
            wild = mp;
            CString = cp++;
        }
    }

    while (*wild == '*') {
        wild++;
    }

    return (*wild == 0);
}

bool CString::WildCmp(const CString& sWild, CaseSensitivity cs) const {
    return CString::WildCmp(sWild, *this, cs);
}

CString& CString::MakeUpper() {
    for (char& c : *this) {
        // TODO use unicode
        c = (char)toupper(c);
    }

    return *this;
}

CString& CString::MakeLower() {
    for (char& c : *this) {
        // TODO use unicode
        c = (char)tolower(c);
    }

    return *this;
}

CString CString::AsUpper() const {
    CString sRet = *this;
    sRet.MakeUpper();
    return sRet;
}

CString CString::AsLower() const {
    CString sRet = *this;
    sRet.MakeLower();
    return sRet;
}

CString::EEscape CString::ToEscape(const CString& sEsc) {
    if (sEsc.Equals("ASCII")) {
        return EASCII;
    } else if (sEsc.Equals("HTML")) {
        return EHTML;
    } else if (sEsc.Equals("URL")) {
        return EURL;
    } else if (sEsc.Equals("SQL")) {
        return ESQL;
    } else if (sEsc.Equals("NAMEDFMT")) {
        return ENAMEDFMT;
    } else if (sEsc.Equals("DEBUG")) {
        return EDEBUG;
    } else if (sEsc.Equals("MSGTAG")) {
        return EMSGTAG;
    } else if (sEsc.Equals("HEXCOLON")) {
        return EHEXCOLON;
    }

    return EASCII;
}

CString CString::Escape_n(EEscape eFrom, EEscape eTo) const {
    CString sRet;
    const char szHex[] = "0123456789ABCDEF";
    const unsigned char* pStart = (const unsigned char*)data();
    const unsigned char* p = (const unsigned char*)data();
    size_type iLength = length();
    sRet.reserve(iLength * 3);
    unsigned char pTmp[21] = {};
    unsigned int iCounted = 0;

    for (unsigned int a = 0; a < iLength; a++, p = pStart + a) {
        unsigned char ch = 0;

        switch (eFrom) {
            case EHTML:
                if ((*p == '&') &&
                    (strnchr((unsigned char*)p, ';', sizeof(pTmp) - 1, pTmp,
                             &iCounted))) {
                    // please note that we do not have any Unicode or UTF-8
                    // support here at all.

                    if ((iCounted >= 3) &&
                        (pTmp[1] == '#')) {  // do XML and HTML &#97; &#x3c
                        int base = 10;

                        if ((pTmp[2] & 0xDF) == 'X') {
                            base = 16;
                        }

                        char* endptr = nullptr;
                        unsigned long int b =
                            strtol((const char*)(pTmp + 2 + (base == 16)),
                                   &endptr, base);

                        if ((*endptr == ';') && (b <= 255)) {
                            // incase they do something like &#7777777777;
                            ch = (unsigned char)b;
                            a += iCounted;
                            break;
                        }
                    }

                    if (ch == 0) {
                        if (!strncasecmp((const char*)&pTmp, "&lt;", 4))
                            ch = '<';
                        else if (!strncasecmp((const char*)&pTmp, "&gt;", 4))
                            ch = '>';
                        else if (!strncasecmp((const char*)&pTmp, "&quot;", 6))
                            ch = '"';
                        else if (!strncasecmp((const char*)&pTmp, "&amp;", 5))
                            ch = '&';
                    }

                    if (ch > 0) {
                        a += iCounted;
                    } else {
                        ch = *p;  // Not a valid escape, just record the &
                    }
                } else {
                    ch = *p;
                }
                break;
            case EASCII:
                ch = *p;
                break;
            case EURL:
                if (*p == '%' && (a + 2) < iLength && isxdigit(*(p + 1)) &&
                    isxdigit(*(p + 2))) {
                    p++;
                    if (isdigit(*p)) {
                        ch = (unsigned char)((*p - '0') << 4);
                    } else {
                        ch = (unsigned char)((tolower(*p) - 'a' + 10) << 4);
                    }

                    p++;
                    if (isdigit(*p)) {
                        ch |= (unsigned char)(*p - '0');
                    } else {
                        ch |= (unsigned char)(tolower(*p) - 'a' + 10);
                    }

                    a += 2;
                } else if (pStart[a] == '+') {
                    ch = ' ';
                } else {
                    ch = *p;
                }

                break;
            case ESQL:
                if (*p != '\\' || iLength < (a + 1)) {
                    ch = *p;
                } else {
                    a++;
                    p++;

                    if (*p == 'n') {
                        ch = '\n';
                    } else if (*p == 'r') {
                        ch = '\r';
                    } else if (*p == '0') {
                        ch = '\0';
                    } else if (*p == 't') {
                        ch = '\t';
                    } else if (*p == 'b') {
                        ch = '\b';
                    } else {
                        ch = *p;
                    }
                }

                break;
            case ENAMEDFMT:
                if (*p != '\\' || iLength < (a + 1)) {
                    ch = *p;
                } else {
                    a++;
                    p++;
                    ch = *p;
                }

                break;
            case EDEBUG:
                if (*p == '\\' && (a + 3) < iLength && *(p + 1) == 'x' &&
                    isxdigit(*(p + 2)) && isxdigit(*(p + 3))) {
                    p += 2;
                    if (isdigit(*p)) {
                        ch = (unsigned char)((*p - '0') << 4);
                    } else {
                        ch = (unsigned char)((tolower(*p) - 'a' + 10) << 4);
                    }

                    p++;
                    if (isdigit(*p)) {
                        ch |= (unsigned char)(*p - '0');
                    } else {
                        ch |= (unsigned char)(tolower(*p) - 'a' + 10);
                    }

                    a += 3;
                } else if (*p == '\\' && a + 1 < iLength && *(p + 1) == '.') {
                    a++;
                    p++;
                    ch = '\\';
                } else {
                    ch = *p;
                }

                break;
            case EMSGTAG:
                if (*p != '\\' || iLength < (a + 1)) {
                    ch = *p;
                } else {
                    a++;
                    p++;

                    if (*p == ':') {
                        ch = ';';
                    } else if (*p == 's') {
                        ch = ' ';
                    } else if (*p == '0') {
                        ch = '\0';
                    } else if (*p == '\\') {
                        ch = '\\';
                    } else if (*p == 'r') {
                        ch = '\r';
                    } else if (*p == 'n') {
                        ch = '\n';
                    } else {
                        ch = *p;
                    }
                }

                break;
            case EHEXCOLON: {
                while (!isxdigit(*p) && a < iLength) {
                    a++;
                    p++;
                }
                if (a == iLength) {
                    continue;
                }
                if (isdigit(*p)) {
                    ch = (unsigned char)((*p - '0') << 4);
                } else {
                    ch = (unsigned char)((tolower(*p) - 'a' + 10) << 4);
                }
                a++;
                p++;
                while (!isxdigit(*p) && a < iLength) {
                    a++;
                    p++;
                }
                if (a == iLength) {
                    continue;
                }
                if (isdigit(*p)) {
                    ch |= (unsigned char)(*p - '0');
                } else {
                    ch |= (unsigned char)(tolower(*p) - 'a' + 10);
                }
            } break;
        }

        switch (eTo) {
            case EHTML:
                if (ch == '<')
                    sRet += "&lt;";
                else if (ch == '>')
                    sRet += "&gt;";
                else if (ch == '"')
                    sRet += "&quot;";
                else if (ch == '&')
                    sRet += "&amp;";
                else {
                    sRet += ch;
                }

                break;
            case EASCII:
                sRet += ch;
                break;
            case EURL:
                if (isalnum(ch) || ch == '_' || ch == '.' || ch == '-') {
                    sRet += ch;
                } else if (ch == ' ') {
                    sRet += '+';
                } else {
                    sRet += '%';
                    sRet += szHex[ch >> 4];
                    sRet += szHex[ch & 0xf];
                }

                break;
            case ESQL:
                if (ch == '\0') {
                    sRet += '\\';
                    sRet += '0';
                } else if (ch == '\n') {
                    sRet += '\\';
                    sRet += 'n';
                } else if (ch == '\t') {
                    sRet += '\\';
                    sRet += 't';
                } else if (ch == '\r') {
                    sRet += '\\';
                    sRet += 'r';
                } else if (ch == '\b') {
                    sRet += '\\';
                    sRet += 'b';
                } else if (ch == '\"') {
                    sRet += '\\';
                    sRet += '\"';
                } else if (ch == '\'') {
                    sRet += '\\';
                    sRet += '\'';
                } else if (ch == '\\') {
                    sRet += '\\';
                    sRet += '\\';
                } else {
                    sRet += ch;
                }

                break;
            case ENAMEDFMT:
                if (ch == '\\') {
                    sRet += '\\';
                    sRet += '\\';
                } else if (ch == '{') {
                    sRet += '\\';
                    sRet += '{';
                } else if (ch == '}') {
                    sRet += '\\';
                    sRet += '}';
                } else {
                    sRet += ch;
                }

                break;
            case EDEBUG:
                if (ch < 0x20 || ch == 0x7F) {
                    sRet += "\\x";
                    sRet += szHex[ch >> 4];
                    sRet += szHex[ch & 0xf];
                } else if (ch == '\\') {
                    sRet += "\\.";
                } else {
                    sRet += ch;
                }

                break;
            case EMSGTAG:
                if (ch == ';') {
                    sRet += '\\';
                    sRet += ':';
                } else if (ch == ' ') {
                    sRet += '\\';
                    sRet += 's';
                } else if (ch == '\0') {
                    sRet += '\\';
                    sRet += '0';
                } else if (ch == '\\') {
                    sRet += '\\';
                    sRet += '\\';
                } else if (ch == '\r') {
                    sRet += '\\';
                    sRet += 'r';
                } else if (ch == '\n') {
                    sRet += '\\';
                    sRet += 'n';
                } else {
                    sRet += ch;
                }

                break;
            case EHEXCOLON: {
                sRet += tolower(szHex[ch >> 4]);
                sRet += tolower(szHex[ch & 0xf]);
                sRet += ":";
            } break;
        }
    }

    if (eTo == EHEXCOLON) {
        sRet.TrimRight(":");
    }

    return sRet;
}

CString CString::Escape_n(EEscape eTo) const { return Escape_n(EASCII, eTo); }

CString& CString::Escape(EEscape eFrom, EEscape eTo) {
    return (*this = Escape_n(eFrom, eTo));
}

CString& CString::Escape(EEscape eTo) { return (*this = Escape_n(eTo)); }

CString CString::Replace_n(const CString& sReplace, const CString& sWith,
                           const CString& sLeft, const CString& sRight,
                           bool bRemoveDelims) const {
    CString sRet = *this;
    CString::Replace(sRet, sReplace, sWith, sLeft, sRight, bRemoveDelims);
    return sRet;
}

unsigned int CString::Replace(const CString& sReplace, const CString& sWith,
                              const CString& sLeft, const CString& sRight,
                              bool bRemoveDelims) {
    return CString::Replace(*this, sReplace, sWith, sLeft, sRight,
                            bRemoveDelims);
}

unsigned int CString::Replace(CString& sStr, const CString& sReplace,
                              const CString& sWith, const CString& sLeft,
                              const CString& sRight, bool bRemoveDelims) {
    unsigned int uRet = 0;
    CString sCopy = sStr;
    sStr.clear();

    size_type uReplaceWidth = sReplace.length();
    size_type uLeftWidth = sLeft.length();
    size_type uRightWidth = sRight.length();
    const char* p = sCopy.c_str();
    bool bInside = false;

    while (*p) {
        if (!bInside && uLeftWidth &&
            strncmp(p, sLeft.c_str(), uLeftWidth) == 0) {
            if (!bRemoveDelims) {
                sStr += sLeft;
            }

            p += uLeftWidth - 1;
            bInside = true;
        } else if (bInside && uRightWidth &&
                   strncmp(p, sRight.c_str(), uRightWidth) == 0) {
            if (!bRemoveDelims) {
                sStr += sRight;
            }

            p += uRightWidth - 1;
            bInside = false;
        } else if (!bInside &&
                   strncmp(p, sReplace.c_str(), uReplaceWidth) == 0) {
            sStr += sWith;
            p += uReplaceWidth - 1;
            uRet++;
        } else {
            sStr.append(p, 1);
        }

        p++;
    }

    return uRet;
}

CString CString::Token(size_t uPos, bool bRest, const CString& sSep,
                       bool bAllowEmpty, const CString& sLeft,
                       const CString& sRight, bool bTrimQuotes) const {
    VCString vsTokens;
    if (Split(sSep, vsTokens, bAllowEmpty, sLeft, sRight, bTrimQuotes) > uPos) {
        CString sRet;

        for (size_t a = uPos; a < vsTokens.size(); a++) {
            if (a > uPos) {
                sRet += sSep;
            }

            sRet += vsTokens[a];

            if (!bRest) {
                break;
            }
        }

        return sRet;
    }

    return Token(uPos, bRest, sSep, bAllowEmpty);
}

CString CString::Token(size_t uPos, bool bRest, const CString& sSep,
                       bool bAllowEmpty) const {
    const char* sep_str = sSep.c_str();
    size_t sep_len = sSep.length();
    const char* str = c_str();
    size_t str_len = length();
    size_t start_pos = 0;
    size_t end_pos;

    if (!bAllowEmpty) {
        while (strncmp(&str[start_pos], sep_str, sep_len) == 0) {
            start_pos += sep_len;
        }
    }

    // First, find the start of our token
    while (uPos != 0 && start_pos < str_len) {
        bool bFoundSep = false;

        while (strncmp(&str[start_pos], sep_str, sep_len) == 0 &&
               (!bFoundSep || !bAllowEmpty)) {
            start_pos += sep_len;
            bFoundSep = true;
        }

        if (bFoundSep) {
            uPos--;
        } else {
            start_pos++;
        }
    }

    // String is over?
    if (start_pos >= str_len) return "";

    // If they want everything from here on, give it to them
    if (bRest) {
        return substr(start_pos);
    }

    // Now look for the end of the token they want
    end_pos = start_pos;
    while (end_pos < str_len) {
        if (strncmp(&str[end_pos], sep_str, sep_len) == 0)
            return substr(start_pos, end_pos - start_pos);

        end_pos++;
    }

    // They want the last token in the string, not something in between
    return substr(start_pos);
}

CString CString::Ellipsize(unsigned int uLen) const {
    if (uLen >= size()) {
        return *this;
    }

    string sRet;

    // @todo this looks suspect
    if (uLen < 4) {
        for (unsigned int a = 0; a < uLen; a++) {
            sRet += ".";
        }

        return sRet;
    }

    sRet = substr(0, uLen - 3) + "...";

    return sRet;
}

CString CString::Left(size_type uCount) const {
    uCount = (uCount > length()) ? length() : uCount;
    return substr(0, uCount);
}

CString CString::Right(size_type uCount) const {
    uCount = (uCount > length()) ? length() : uCount;
    return substr(length() - uCount, uCount);
}

CString::size_type CString::URLSplit(MCString& msRet) const {
    msRet.clear();

    VCString vsPairs;
    Split("&", vsPairs);

    for (const CString& sPair : vsPairs) {
        msRet[sPair.Token(0, false, "=")
                  .Escape(CString::EURL, CString::EASCII)] =
            sPair.Token(1, true, "=").Escape(CString::EURL, CString::EASCII);
    }

    return msRet.size();
}

CString::size_type CString::OptionSplit(MCString& msRet,
                                        bool bUpperKeys) const {
    CString sName;
    CString sCopy(*this);
    msRet.clear();

    while (!sCopy.empty()) {
        sName = sCopy.Token(0, false, "=", false, "\"", "\"", false).Trim_n();
        sCopy =
            sCopy.Token(1, true, "=", false, "\"", "\"", false).TrimLeft_n();

        if (sName.empty()) {
            continue;
        }

        VCString vsNames;
        sName.Split(" ", vsNames, false, "\"", "\"");

        for (unsigned int a = 0; a < vsNames.size(); a++) {
            CString sKeyName = vsNames[a];

            if (bUpperKeys) {
                sKeyName.MakeUpper();
            }

            if ((a + 1) == vsNames.size()) {
                msRet[sKeyName] = sCopy.Token(0, false, " ", false, "\"", "\"");
                sCopy = sCopy.Token(1, true, " ", false, "\"", "\"", false);
            } else {
                msRet[sKeyName] = "";
            }
        }
    }

    return msRet.size();
}

CString::size_type CString::QuoteSplit(VCString& vsRet) const {
    vsRet.clear();
    return Split(" ", vsRet, false, "\"", "\"", true);
}

CString::size_type CString::Split(const CString& sDelim, VCString& vsRet,
                                  bool bAllowEmpty, const CString& sLeft,
                                  const CString& sRight, bool bTrimQuotes,
                                  bool bTrimWhiteSpace) const {
    vsRet.clear();

    if (empty()) {
        return 0;
    }

    CString sTmp;
    bool bInside = false;
    size_type uDelimLen = sDelim.length();
    size_type uLeftLen = sLeft.length();
    size_type uRightLen = sRight.length();
    const char* p = c_str();

    if (!bAllowEmpty) {
        while (strncasecmp(p, sDelim.c_str(), uDelimLen) == 0) {
            p += uDelimLen;
        }
    }

    while (*p) {
        if (uLeftLen && uRightLen && !bInside &&
            strncasecmp(p, sLeft.c_str(), uLeftLen) == 0) {
            if (!bTrimQuotes) {
                sTmp += sLeft;
            }

            p += uLeftLen;
            bInside = true;
            continue;
        }

        if (uLeftLen && uRightLen && bInside &&
            strncasecmp(p, sRight.c_str(), uRightLen) == 0) {
            if (!bTrimQuotes) {
                sTmp += sRight;
            }

            p += uRightLen;
            bInside = false;
            continue;
        }

        if (uDelimLen && !bInside &&
            strncasecmp(p, sDelim.c_str(), uDelimLen) == 0) {
            if (bTrimWhiteSpace) {
                sTmp.Trim();
            }

            vsRet.push_back(sTmp);
            sTmp.clear();
            p += uDelimLen;

            if (!bAllowEmpty) {
                while (strncasecmp(p, sDelim.c_str(), uDelimLen) == 0) {
                    p += uDelimLen;
                }
            }

            bInside = false;
            continue;
        } else {
            sTmp += *p;
        }

        p++;
    }

    if (!sTmp.empty()) {
        if (bTrimWhiteSpace) {
            sTmp.Trim();
        }

        vsRet.push_back(sTmp);
    }

    return vsRet.size();
}

CString::size_type CString::Split(const CString& sDelim, SCString& ssRet,
                                  bool bAllowEmpty, const CString& sLeft,
                                  const CString& sRight, bool bTrimQuotes,
                                  bool bTrimWhiteSpace) const {
    VCString vsTokens;

    Split(sDelim, vsTokens, bAllowEmpty, sLeft, sRight, bTrimQuotes,
          bTrimWhiteSpace);

    ssRet.clear();

    for (const CString& sToken : vsTokens) {
        ssRet.insert(sToken);
    }

    return ssRet.size();
}

CString CString::NamedFormat(const CString& sFormat, const MCString& msValues) {
    CString sRet;

    CString sKey;
    bool bEscape = false;
    bool bParam = false;
    const char* p = sFormat.c_str();

    while (*p) {
        if (!bParam) {
            if (bEscape) {
                sRet += *p;
                bEscape = false;
            } else if (*p == '\\') {
                bEscape = true;
            } else if (*p == '{') {
                bParam = true;
                sKey.clear();
            } else {
                sRet += *p;
            }

        } else {
            if (bEscape) {
                sKey += *p;
                bEscape = false;
            } else if (*p == '\\') {
                bEscape = true;
            } else if (*p == '}') {
                bParam = false;
                MCString::const_iterator it = msValues.find(sKey);
                if (it != msValues.end()) {
                    sRet += (*it).second;
                }
            } else {
                sKey += *p;
            }
        }

        p++;
    }

    return sRet;
}

CString CString::RandomString(unsigned int uLength) {
    const char chars[] =
        "abcdefghijklmnopqrstuvwxyz"
        "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
        "0123456789!?.,:;/*-+_()";
    // -1 because sizeof() includes the trailing '\0' byte
    const size_t len = sizeof(chars) / sizeof(chars[0]) - 1;
    size_t p;
    CString sRet;

    for (unsigned int a = 0; a < uLength; a++) {
        p = (size_t)(len * (rand() / (RAND_MAX + 1.0)));
        sRet += chars[p];
    }

    return sRet;
}

bool CString::Base64Encode(unsigned int uWrap) {
    CString sCopy(*this);
    return sCopy.Base64Encode(*this, uWrap);
}

unsigned long CString::Base64Decode() {
    CString sCopy(*this);
    return sCopy.Base64Decode(*this);
}

CString CString::Base64Encode_n(unsigned int uWrap) const {
    CString sRet;
    Base64Encode(sRet, uWrap);
    return sRet;
}

CString CString::Base64Decode_n() const {
    CString sRet;
    Base64Decode(sRet);
    return sRet;
}

bool CString::Base64Encode(CString& sRet, unsigned int uWrap) const {
    const char b64table[] =
        "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
    sRet.clear();
    size_t len = size();
    const unsigned char* input = (const unsigned char*)c_str();
    unsigned char* output, *p;
    size_t i = 0, mod = len % 3, toalloc;
    toalloc = (len / 3) * 4 + (3 - mod) % 3 + 1 + 8;

    if (uWrap) {
        toalloc += len / 57;
        if (len % 57) {
            toalloc++;
        }
    }

    if (toalloc < len) {
        return 0;
    }

    p = output = new unsigned char[toalloc]{};

    while (i < len - mod) {
        *p++ = b64table[input[i++] >> 2];
        *p++ = b64table[((input[i - 1] << 4) | (input[i] >> 4)) & 0x3f];
        *p++ = b64table[((input[i] << 2) | (input[i + 1] >> 6)) & 0x3f];
        *p++ = b64table[input[i + 1] & 0x3f];
        i += 2;

        if (uWrap && !(i % 57)) {
            *p++ = '\n';
        }
    }

    if (!mod) {
        if (uWrap && i % 57) {
            *p++ = '\n';
        }
    } else {
        *p++ = b64table[input[i++] >> 2];
        *p++ = b64table[((input[i - 1] << 4) | (input[i] >> 4)) & 0x3f];
        if (mod == 1) {
            *p++ = '=';
        } else {
            *p++ = b64table[(input[i] << 2) & 0x3f];
        }

        *p++ = '=';

        if (uWrap) {
            *p++ = '\n';
        }
    }

    *p = 0;
    sRet = (char*)output;
    delete[] output;
    return true;
}

unsigned long CString::Base64Decode(CString& sRet) const {
    CString sTmp(*this);
    // remove new lines
    sTmp.Replace("\r", "");
    sTmp.Replace("\n", "");

    const char* in = sTmp.c_str();
    char c, c1, *p;
    unsigned long i;
    unsigned long uLen = sTmp.size();
    char* out = new char[uLen + 1]{};

    for (i = 0, p = out; i < uLen; i++) {
        c = (char)base64_table[(unsigned char)in[i++]];
        c1 = (char)base64_table[(unsigned char)in[i++]];
        *p++ = char((c << 2) | ((c1 >> 4) & 0x3));

        if (i < uLen) {
            if (in[i] == '=') {
                break;
            }
            c = (char)base64_table[(unsigned char)in[i]];
            *p++ = char(((c1 << 4) & 0xf0) | ((c >> 2) & 0xf));
        }

        if (++i < uLen) {
            if (in[i] == '=') {
                break;
            }
            *p++ = char(((c << 6) & 0xc0) |
                        (char)base64_table[(unsigned char)in[i]]);
        }
    }

    *p = '\0';
    unsigned long uRet = p - out;
    sRet.clear();
    sRet.append(out, uRet);
    delete[] out;

    return uRet;
}

CString CString::MD5() const { return (const char*)CMD5(*this); }

CString CString::SHA256() const {
    unsigned char digest[SHA256_DIGEST_SIZE];
    char digest_hex[SHA256_DIGEST_SIZE * 2 + 1];
    const unsigned char* message = (const unsigned char*)c_str();

    sha256(message, length(), digest);

    snprintf(digest_hex, sizeof(digest_hex),
             "%02x%02x%02x%02x%02x%02x%02x%02x"
             "%02x%02x%02x%02x%02x%02x%02x%02x"
             "%02x%02x%02x%02x%02x%02x%02x%02x"
             "%02x%02x%02x%02x%02x%02x%02x%02x",
             digest[0], digest[1], digest[2], digest[3], digest[4], digest[5],
             digest[6], digest[7], digest[8], digest[9], digest[10], digest[11],
             digest[12], digest[13], digest[14], digest[15], digest[16],
             digest[17], digest[18], digest[19], digest[20], digest[21],
             digest[22], digest[23], digest[24], digest[25], digest[26],
             digest[27], digest[28], digest[29], digest[30], digest[31]);

    return digest_hex;
}

#ifdef HAVE_LIBSSL
CString CString::Encrypt_n(const CString& sPass, const CString& sIvec) const {
    CString sRet;
    sRet.Encrypt(sPass, sIvec);
    return sRet;
}

CString CString::Decrypt_n(const CString& sPass, const CString& sIvec) const {
    CString sRet;
    sRet.Decrypt(sPass, sIvec);
    return sRet;
}

void CString::Encrypt(const CString& sPass, const CString& sIvec) {
    Crypt(sPass, true, sIvec);
}

void CString::Decrypt(const CString& sPass, const CString& sIvec) {
    Crypt(sPass, false, sIvec);
}

void CString::Crypt(const CString& sPass, bool bEncrypt, const CString& sIvec) {
    unsigned char szIvec[8] = {0, 0, 0, 0, 0, 0, 0, 0};
    BF_KEY bKey;

    if (sIvec.length() >= 8) {
        memcpy(szIvec, sIvec.data(), 8);
    }

    BF_set_key(&bKey, (unsigned int)sPass.length(),
               (unsigned char*)sPass.data());
    unsigned int uPad = (length() % 8);

    if (uPad) {
        uPad = 8 - uPad;
        append(uPad, '\0');
    }

    size_t uLen = length();
    unsigned char* szBuff = (unsigned char*)malloc(uLen);
    BF_cbc_encrypt((const unsigned char*)data(), szBuff, uLen, &bKey, szIvec,
                   ((bEncrypt) ? BF_ENCRYPT : BF_DECRYPT));

    clear();
    append((const char*)szBuff, uLen);
    free(szBuff);
}
#endif  // HAVE_LIBSSL

CString CString::ToPercent(double d) {
    char szRet[32];
    snprintf(szRet, 32, "%.02f%%", d);
    return szRet;
}

CString CString::ToByteStr(unsigned long long d) {
    const unsigned long long KiB = 1024;
    const unsigned long long MiB = KiB * 1024;
    const unsigned long long GiB = MiB * 1024;
    const unsigned long long TiB = GiB * 1024;

    if (d > TiB) {
        return CString(d / TiB) + " TiB";
    } else if (d > GiB) {
        return CString(d / GiB) + " GiB";
    } else if (d > MiB) {
        return CString(d / MiB) + " MiB";
    } else if (d > KiB) {
        return CString(d / KiB) + " KiB";
    }

    return CString(d) + " B";
}

CString CString::ToTimeStr(unsigned long s) {
    const unsigned long m = 60;
    const unsigned long h = m * 60;
    const unsigned long d = h * 24;
    const unsigned long w = d * 7;
    const unsigned long y = d * 365;
    CString sRet;

#define TIMESPAN(time, str)                  \
    if (s >= time) {                         \
        sRet += CString(s / time) + str " "; \
        s = s % time;                        \
    }
    TIMESPAN(y, "y");
    TIMESPAN(w, "w");
    TIMESPAN(d, "d");
    TIMESPAN(h, "h");
    TIMESPAN(m, "m");
    TIMESPAN(1, "s");

    if (sRet.empty()) return "0s";

    return sRet.RightChomp_n();
}

bool CString::ToBool() const {
    CString sTrimmed = Trim_n();
    return (!sTrimmed.Trim_n("0").empty() && !sTrimmed.Equals("false") &&
            !sTrimmed.Equals("off") && !sTrimmed.Equals("no") &&
            !sTrimmed.Equals("n"));
}

short CString::ToShort() const {
    return (short int)strtol(this->c_str(), (char**)nullptr, 10);
}
unsigned short CString::ToUShort() const {
    return (unsigned short int)strtoul(this->c_str(), (char**)nullptr, 10);
}
unsigned int CString::ToUInt() const {
    return (unsigned int)strtoul(this->c_str(), (char**)nullptr, 10);
}
int CString::ToInt() const {
    return (int)strtol(this->c_str(), (char**)nullptr, 10);
}
long CString::ToLong() const {
    return strtol(this->c_str(), (char**)nullptr, 10);
}
unsigned long CString::ToULong() const { return strtoul(c_str(), nullptr, 10); }
unsigned long long CString::ToULongLong() const {
    return strtoull(c_str(), nullptr, 10);
}
long long CString::ToLongLong() const { return strtoll(c_str(), nullptr, 10); }
double CString::ToDouble() const { return strtod(c_str(), nullptr); }

bool CString::Trim(const CString& s) {
    bool bLeft = TrimLeft(s);
    return (TrimRight(s) || bLeft);
}

bool CString::TrimLeft(const CString& s) {
    size_type i = find_first_not_of(s);

    if (i == 0) return false;

    if (i != npos)
        this->erase(0, i);
    else
        this->clear();

    return true;
}

bool CString::TrimRight(const CString& s) {
    size_type i = find_last_not_of(s);

    if (i + 1 == length()) return false;

    if (i != npos)
        this->erase(i + 1, npos);
    else
        this->clear();

    return true;
}

CString CString::Trim_n(const CString& s) const {
    CString sRet = *this;
    sRet.Trim(s);
    return sRet;
}

CString CString::TrimLeft_n(const CString& s) const {
    CString sRet = *this;
    sRet.TrimLeft(s);
    return sRet;
}

CString CString::TrimRight_n(const CString& s) const {
    CString sRet = *this;
    sRet.TrimRight(s);
    return sRet;
}

bool CString::TrimPrefix(const CString& sPrefix) {
    if (StartsWith(sPrefix)) {
        LeftChomp(sPrefix.length());
        return true;
    } else {
        return false;
    }
}

bool CString::TrimSuffix(const CString& sSuffix) {
    if (Right(sSuffix.length()).Equals(sSuffix)) {
        RightChomp(sSuffix.length());
        return true;
    } else {
        return false;
    }
}

size_t CString::Find(const CString& s, CaseSensitivity cs) const {
    if (cs == CaseSensitive) {
        return find(s);
    } else {
        return AsLower().find(s.AsLower());
    }
}

bool CString::StartsWith(const CString& sPrefix, CaseSensitivity cs) const {
    return Left(sPrefix.length()).Equals(sPrefix, cs);
}

bool CString::EndsWith(const CString& sSuffix, CaseSensitivity cs) const {
    return Right(sSuffix.length()).Equals(sSuffix, cs);
}

bool CString::Contains(const CString& s, CaseSensitivity cs) const {
    return Find(s, cs) != npos;
}

CString CString::TrimPrefix_n(const CString& sPrefix) const {
    CString sRet = *this;
    sRet.TrimPrefix(sPrefix);
    return sRet;
}

CString CString::TrimSuffix_n(const CString& sSuffix) const {
    CString sRet = *this;
    sRet.TrimSuffix(sSuffix);
    return sRet;
}

CString CString::LeftChomp_n(size_type uLen) const {
    CString sRet = *this;
    sRet.LeftChomp(uLen);
    return sRet;
}

CString CString::RightChomp_n(size_type uLen) const {
    CString sRet = *this;
    sRet.RightChomp(uLen);
    return sRet;
}

bool CString::LeftChomp(size_type uLen) {
    bool bRet = false;

    while ((uLen--) && (length())) {
        erase(0, 1);
        bRet = true;
    }

    return bRet;
}

bool CString::RightChomp(size_type uLen) {
    bool bRet = false;

    while ((uLen--) && (length())) {
        erase(length() - 1);
        bRet = true;
    }

    return bRet;
}

CString CString::StripControls_n() const {
    CString sRet;
    const unsigned char* pStart = (const unsigned char*)data();
    unsigned char ch = *pStart;
    size_type iLength = length();
    sRet.reserve(iLength);
    bool colorCode = false;
    unsigned int digits = 0;
    bool comma = false;

    for (unsigned int a = 0; a < iLength; a++, ch = pStart[a]) {
        // Color code. Format: \x03([0-9]{1,2}(,[0-9]{1,2})?)?
        if (ch == 0x03) {
            colorCode = true;
            digits = 0;
            comma = false;
            continue;
        }
        if (colorCode) {
            if (isdigit(ch) && digits < 2) {
                digits++;
                continue;
            }
            if (ch == ',' && !comma) {
                comma = true;
                digits = 0;
                continue;
            }

            colorCode = false;

            if (digits == 0 && comma) {
                // There was a ',' which wasn't followed by digits, we should
                // print it.
                sRet += ',';
            }
        }
        // CO controls codes
        if (ch < 0x20 || ch == 0x7F) continue;
        sRet += ch;
    }
    if (colorCode && digits == 0 && comma) {
        sRet += ',';
    }

    sRet.reserve(0);
    return sRet;
}

CString& CString::StripControls() { return (*this = StripControls_n()); }

//////////////// MCString ////////////////
const MCString MCString::EmptyMap;

MCString::status_t MCString::WriteToDisk(const CString& sPath,
                                         mode_t iMode) const {
    CFile cFile(sPath);

    if (this->empty()) {
        if (!cFile.Exists()) return MCS_SUCCESS;
        if (cFile.Delete()) return MCS_SUCCESS;
    }

    if (!cFile.Open(O_WRONLY | O_CREAT | O_TRUNC, iMode)) {
        return MCS_EOPEN;
    }

    for (const auto& it : *this) {
        CString sKey = it.first;
        CString sValue = it.second;
        if (!WriteFilter(sKey, sValue)) {
            return MCS_EWRITEFIL;
        }

        if (sKey.empty()) {
            continue;
        }

        if (cFile.Write(Encode(sKey) + " " + Encode(sValue) + "\n") <= 0) {
            return MCS_EWRITE;
        }
    }

    cFile.Close();

    return MCS_SUCCESS;
}

MCString::status_t MCString::ReadFromDisk(const CString& sPath) {
    clear();
    CFile cFile(sPath);
    if (!cFile.Open(O_RDONLY)) {
        return MCS_EOPEN;
    }

    CString sBuffer;

    while (cFile.ReadLine(sBuffer)) {
        sBuffer.Trim();
        CString sKey = sBuffer.Token(0);
        CString sValue = sBuffer.Token(1);
        Decode(sKey);
        Decode(sValue);

        if (!ReadFilter(sKey, sValue)) return MCS_EREADFIL;

        (*this)[sKey] = sValue;
    }
    cFile.Close();

    return MCS_SUCCESS;
}

static const char hexdigits[] = "0123456789abcdef";

CString& MCString::Encode(CString& sValue) const {
    CString sTmp;
    for (unsigned char c : sValue) {
        // isalnum() needs unsigned char as argument and this code
        // assumes unsigned, too.
        if (isalnum(c)) {
            sTmp += c;
        } else {
            sTmp += "%";
            sTmp += hexdigits[c >> 4];
            sTmp += hexdigits[c & 0xf];
            sTmp += ";";
        }
    }
    sValue = sTmp;
    return sValue;
}

CString& MCString::Decode(CString& sValue) const {
    const char* pTmp = sValue.c_str();
    char* endptr;
    CString sTmp;

    while (*pTmp) {
        if (*pTmp != '%') {
            sTmp += *pTmp++;
        } else {
            char ch = (char)strtol(pTmp + 1, &endptr, 16);
            if (*endptr == ';') {
                sTmp += ch;
                pTmp = ++endptr;
            } else {
                sTmp += *pTmp++;
            }
        }
    }

    sValue = sTmp;
    return sValue;
}
