//
// VMime library (http://www.vmime.org)
// Copyright (C) 2002 Vincent Richard <vincent@vmime.org>
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 3 of
// the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// Linking this library statically or dynamically with other modules is making
// a combined work based on this library.  Thus, the terms and conditions of
// the GNU General Public License cover the whole combination.
//

#include "vmime/emailAddress.hpp"

#include "vmime/platform.hpp"

#include "vmime/parserHelpers.hpp"
#include "vmime/utility/outputStreamAdapter.hpp"
#include "vmime/utility/outputStreamStringAdapter.hpp"
#include "vmime/utility/stringUtils.hpp"


namespace vmime {


/** Decode an IDNA-encoded domain name ("xn--5rtw95l.xn--wgv71a")
  * to a fully decoded domain name in UTF-8 ("黒川.日本").
  *
  * @param idnaDomain domain name encoded with IDNA
  * @return decoded domain name in UTF-8
  */
static const string domainNameFromIDNA(const string& idnaDomain) {

	std::ostringstream domainName;
	size_t p = 0;

	for (size_t n = idnaDomain.find('.', p) ;
	     (n = idnaDomain.find('.', p)) != string::npos ; p = n + 1) {

		const string encodedPart(idnaDomain.begin() + p, idnaDomain.begin() + n);

		if (encodedPart.length() > 4 &&
		    encodedPart[0] == 'x' && encodedPart[1] == 'n' &&
		    encodedPart[2] == '-' && encodedPart[3] == '-') {

			string decodedPart;
			charset::convert(
				encodedPart, decodedPart,
				vmime::charsets::IDNA, vmime::charsets::UTF_8
			);

			domainName << decodedPart << '.';

		} else {

			domainName << encodedPart << '.';  // not encoded
		}
	}

	if (p < idnaDomain.length()) {

		const string encodedPart(idnaDomain.begin() + p, idnaDomain.end());

		if (encodedPart.length() > 4 &&
		    encodedPart[0] == 'x' && encodedPart[1] == 'n' &&
		    encodedPart[2] == '-' && encodedPart[3] == '-') {

			string decodedPart;
			charset::convert(
				encodedPart, decodedPart,
				vmime::charsets::IDNA, vmime::charsets::UTF_8
			);

			domainName << decodedPart;

		} else {

			domainName << encodedPart;  // not encoded
		}
	}

	return domainName.str();
}


/** Encode an UTF-8 domain name ("黒川.日本") to an IDNA-encoded
  * domain name ("xn--5rtw95l.xn--wgv71a").
  *
  * @param domainName domain name in UTF-8
  * @return domain name encoded with IDNA
  */
static const string domainNameToIDNA(const string& domainName) {

	std::ostringstream idnaDomain;
	size_t p = 0;

	for (size_t n = domainName.find('.', p) ;
	     (n = domainName.find('.', p)) != string::npos ; p = n + 1) {

		string idnaPart;
		charset::convert(
			string(domainName.begin() + p, domainName.begin() + n), idnaPart,
			vmime::charsets::UTF_8, vmime::charsets::IDNA
		);

		idnaDomain << idnaPart << '.';
	}

	if (p < domainName.length()) {

		string idnaPart;
		charset::convert(
			string(domainName.begin() + p, domainName.end()), idnaPart,
			vmime::charsets::UTF_8, vmime::charsets::IDNA
		);

		idnaDomain << idnaPart;
	}

	return idnaDomain.str();
}




emailAddress::emailAddress() {

}


emailAddress::emailAddress(const emailAddress& eml)
	: component(),
	  m_localName(eml.m_localName),
	  m_domainName(eml.m_domainName) {

}


emailAddress::emailAddress(const string& email) {

	parse(email);
}


emailAddress::emailAddress(const char* email) {

	parse(email);
}


emailAddress::emailAddress(const string& localName, const string& domainName)
	: component(),
	  m_localName(word(localName, vmime::charsets::UTF_8)),
	  m_domainName(word(domainName, vmime::charsets::UTF_8)) {

}


emailAddress::emailAddress(const word& localName, const word& domainName)
	: component(),
	  m_localName(localName),
	  m_domainName(domainName) {

}


void emailAddress::parseImpl(
	const parsingContext& /* ctx */,
	const string& buffer,
	const size_t position,
	const size_t end,
	size_t* newPosition
) {

	const char* const pend = buffer.data() + end;
	const char* const pstart = buffer.data() + position;
	const char* p = pstart;

	enum ParserStates {
		State_Before,
		State_LocalPartStart,
		State_LocalPartMiddle,
		State_LocalPartComment,
		State_LocalPartQuoted,
		State_LocalPartRFC2047Start,
		State_LocalPartRFC2047Middle,
		State_LocalPartRFC2047MiddleQM,
		State_LocalPartRFC2047End,
		State_DomainPartStart,
		State_DomainPartMiddle,
		State_DomainPartComment,
		State_End,
		State_Error
	} state = State_Before;

	std::ostringstream localPart;
	std::ostringstream domainPart;

	bool escapeNext = false;  // for quoting
	bool prevIsDot = false;
	bool atFound = false;
	bool stop = false;
	int commentLevel = 0;
	bool localPartIsRFC2047 = false;

	while (p < pend && !stop) {

		const char c = *p;

		if ((localPart.str().length() + domainPart.str().length()) >= 256) {
			state = State_Error;
			break;
		}

		switch (state) {

			case State_Before:

				if (parserHelpers::isSpace(c)) {
					++p;
				} else {
					state = State_LocalPartStart;
				}

				break;

			case State_LocalPartStart:

				if (c == '"') {

					state = State_LocalPartQuoted;
					++p;

				} else if (c == '=') {

					state = State_LocalPartRFC2047Start;
					++p;

				} else if (c == '(') {

					state = State_LocalPartComment;
					++commentLevel;
					++p;

				} else {

					state = State_LocalPartMiddle;
					localPart << c;
					++p;
				}

				break;

			case State_LocalPartComment:

				if (escapeNext) {

					escapeNext = false;
					++p;

				} else if (c == '\\') {

					escapeNext = true;
					++p;

				} else if (c == '(') {

					++commentLevel;
					++p;

				} else if (c == ')') {

					if (--commentLevel == 0) {
						// End of comment
						state = State_LocalPartMiddle;
					}

					++p;

				} else {

					// Comment continues
					++p;
				}

				break;

			case State_LocalPartQuoted:

				if (escapeNext) {

					escapeNext = false;

					if (c == '"' || c == '\\') {

						localPart << c;
						++p;

					} else {

						// This char cannot be escaped
						state = State_Error;
					}

				} else if (c == '"') {

					// End of quoted string
					state = State_LocalPartMiddle;
					++p;

				} else if (c == '\\') {

					escapeNext = true;
					++p;

				} else {

					localPart << c;
					++p;
				}

				break;

			case State_LocalPartRFC2047Start:

				if (c == '?') {

					state = State_LocalPartRFC2047Middle;
					localPart << "=?";
					localPartIsRFC2047 = true;
					++p;

				} else {

					state = State_LocalPartMiddle;
					localPart << '=';
					localPart << c;
					++p;
				}

				break;

			case State_LocalPartMiddle:

				if (c == '.') {

					prevIsDot = true;
					localPart << c;
					++p;

				} else if (c == '"' && prevIsDot) {

					prevIsDot = false;
					state = State_LocalPartQuoted;
					++p;

				} else if (c == '(') {

					// By allowing comments anywhere in the local part,
					// we are more permissive than RFC-2822
					state = State_LocalPartComment;
					++commentLevel;
					++p;

				} else if (c == '@') {

					atFound = true;
					state = State_DomainPartStart;
					++p;

				} else if (parserHelpers::isSpace(c)) {

					// Allow not specifying domain part
					state = State_End;

				} else {

					prevIsDot = false;
					localPart << c;
					++p;
				}

				break;

			case State_LocalPartRFC2047Middle:

				if (c == '?') {

					state = State_LocalPartRFC2047MiddleQM;
					++p;

				} else {

					localPart << c;
					++p;
				}

				break;

			case State_LocalPartRFC2047MiddleQM:

				if (c == '=') {

					// End of RFC-2047 encoded word
					state = State_LocalPartRFC2047End;
					localPart << "?=";
					++p;

				} else {

					state = State_LocalPartRFC2047Middle;
					localPart << '?';
					localPart << c;
					++p;
				}

				break;

			case State_LocalPartRFC2047End:

				if (c == '@') {

					atFound = true;
					state = State_DomainPartStart;
					++p;

				} else {

					state = State_End;
				}

				break;

			case State_DomainPartStart:

				if (c == '(') {

					state = State_DomainPartComment;
					++commentLevel;
					++p;

				} else {

					state = State_DomainPartMiddle;
					domainPart << c;
					++p;
				}

				break;

			case State_DomainPartMiddle:

				if (parserHelpers::isSpace(c)) {

					state = State_End;

				} else if (c == '(') {

					// By allowing comments anywhere in the domain part,
					// we are more permissive than RFC-2822
					state = State_DomainPartComment;
					++commentLevel;
					++p;

				} else {

					domainPart << c;
					++p;
				}

				break;

			case State_DomainPartComment:

				if (escapeNext) {

					escapeNext = false;
					++p;

				} else if (c == '\\') {

					escapeNext = true;
					++p;

				} else if (c == '(') {

					++commentLevel;
					++p;

				} else if (c == ')') {

					if (--commentLevel == 0) {

						// End of comment
						state = State_DomainPartMiddle;
					}

					++p;

				} else {

					// Comment continues
					++p;
				}

				break;

			case State_End:
			case State_Error:

				stop = true;
				break;
		}
	}

	if (p == pend && state != State_Error) {

		if (state == State_DomainPartMiddle) {
			state = State_End;
		} else if (state == State_LocalPartMiddle) {
			state = State_End;  // allow not specifying domain part
		}
	}

	if (state != State_End) {

		m_localName = word("invalid", vmime::charsets::UTF_8);
		m_domainName = word("invalid", vmime::charsets::UTF_8);

	} else {

		// If the domain part is missing, use local host name
		if (domainPart.str().empty() && !atFound) {
			domainPart << platform::getHandler()->getHostName();
		}

		if (localPartIsRFC2047) {
			m_localName.parse(localPart.str());
		} else {
			m_localName = word(localPart.str(), vmime::charsets::UTF_8);
		}

		m_domainName = word(domainNameFromIDNA(domainPart.str()), vmime::charsets::UTF_8);
	}

	setParsedBounds(position, p - pend);

	if (newPosition) {
		*newPosition = p - pend;
	}
}


void emailAddress::generateImpl(
	const generationContext& ctx,
	utility::outputStream& os,
	const size_t curLinePos,
	size_t* newLinePos
) const {

	string localPart, domainPart;

	if (ctx.getInternationalizedEmailSupport() &&
	    (!utility::stringUtils::is7bit(m_localName.getBuffer()) ||
	     !utility::stringUtils::is7bit(m_domainName.getBuffer()))) {

		// Local part
		string localPartUTF8(m_localName.getConvertedText(vmime::charsets::UTF_8));
		word localPartWord(localPartUTF8, vmime::charsets::UTF_8);

		vmime::utility::outputStreamStringAdapter os(localPart);
		localPartWord.generate(ctx, os, 0, NULL, text::FORCE_NO_ENCODING | text::QUOTE_IF_NEEDED, NULL);

		// Domain part
		domainPart = m_domainName.getConvertedText(vmime::charsets::UTF_8);

	} else {

		// Local part
		vmime::utility::outputStreamStringAdapter os(localPart);
		m_localName.generate(ctx, os, 0, NULL, text::QUOTE_IF_NEEDED, NULL);

		// Domain part as IDNA
		domainPart = domainNameToIDNA(m_domainName.getConvertedText(vmime::charsets::UTF_8));
	}

	os << localPart
	   << "@"
	   << domainPart;

	if (newLinePos) {

		*newLinePos = curLinePos
			+ localPart.length()
			+ 1 // @
			+ domainPart.length();
	}
}


bool emailAddress::operator==(const class emailAddress& eml) const {

	return m_localName == eml.m_localName &&
	       m_domainName == eml.m_domainName;
}


bool emailAddress::operator!=(const class emailAddress& eml) const {

	return !(*this == eml);
}


void emailAddress::copyFrom(const component& other) {

	const emailAddress& source = dynamic_cast <const emailAddress&>(other);

	m_localName = source.m_localName;
	m_domainName = source.m_domainName;
}


emailAddress& emailAddress::operator=(const emailAddress& other) {

	copyFrom(other);
	return *this;
}


shared_ptr <component>emailAddress::clone() const {

	return make_shared <emailAddress>(*this);
}


const word& emailAddress::getLocalName() const {

	return m_localName;
}


void emailAddress::setLocalName(const word& localName) {

	m_localName = localName;
}


const word& emailAddress::getDomainName() const {

	return m_domainName;
}


void emailAddress::setDomainName(const word& domainName) {

	m_domainName = domainName;
}


const std::vector <shared_ptr <component> > emailAddress::getChildComponents() {

	return std::vector <shared_ptr <component> >();
}


bool emailAddress::isEmpty() const {

	return m_localName.isEmpty();
}


const string emailAddress::toString() const {

	std::ostringstream oss;
	utility::outputStreamAdapter adapter(oss);

	generationContext ctx(generationContext::getDefaultContext());
	ctx.setMaxLineLength(lineLengthLimits::infinite);

	generateImpl(ctx, adapter, 0, NULL);

	return oss.str();
}


const text emailAddress::toText() const {

	text txt;
	txt.appendWord(make_shared <vmime::word>(m_localName));
	txt.appendWord(make_shared <vmime::word>("@", vmime::charsets::US_ASCII));
	txt.appendWord(make_shared <vmime::word>(m_domainName));

	return txt;
}


} // vmime