/*
  gpgsignkeyeditinteractor.cpp - Edit Interactor to change the expiry time of an OpenPGP key
  Copyright (C) 2007 Klarälvdalens Datakonsult AB

  This file is part of GPGME++.

  GPGME++ is free software; you can redistribute it and/or
  modify it under the terms of the GNU Library General Public
  License as published by the Free Software Foundation; either
  version 2 of the License, or (at your option) any later version.

  GPGME++ 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 Library General Public License for more details.

  You should have received a copy of the GNU Library General Public License
  along with GPGME++; see the file COPYING.LIB.  If not, write to the
  Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  Boston, MA 02110-1301, USA.
*/

#include "gpgsignkeyeditinteractor.h"
#include "error.h"
#include "key.h"

#include <gpgme.h>

#include <boost/tuple/tuple.hpp>
#include <boost/tuple/tuple_comparison.hpp>

#include <map>
#include <string>
#include <sstream>

#include <cassert>
#include <cstring>

using std::strcmp;

// avoid conflict (msvc)
#ifdef ERROR
# undef ERROR
#endif

#ifdef _MSC_VER
#undef snprintf
#define snprintf _snprintf
#endif

using namespace boost;
using namespace GpgME;

class GpgSignKeyEditInteractor::Private
{
public:
    Private();

    std::string scratch;
    bool started;
    int options;
    std::vector<unsigned int> userIDs;
    std::vector<unsigned int>::const_iterator currentId, nextId;
    unsigned int checkLevel;

    const char *command() const
    {
        const bool local = (options & Exportable) == 0;
        const bool nonRevoc = options & NonRevocable;
        const bool trust = options & Trust;
        //TODO: check if all combinations are valid
        if (local && nonRevoc && trust) {
            return "ltnrsign";
        }
        if (local && nonRevoc) {
            return "lnrsign";
        }
        if (local && trust) {
            return "ltsign";
        }
        if (local) {
            return "lsign";
        }
        if (nonRevoc && trust) {
            return "tnrsign";
        }
        if (nonRevoc) {
            return "nrsign";
        }
        if (trust) {
            return "tsign";
        }
        return "sign";
    }

    bool signAll() const
    {
        return userIDs.empty();
    }
    unsigned int nextUserID()
    {
        assert(nextId != userIDs.end());
        currentId = nextId++;
        return currentUserID();
    }

    bool allUserIDsListed() const
    {
        return nextId == userIDs.end();
    }

    unsigned int currentUserID() const
    {
        assert(currentId != userIDs.end());
        return *currentId + 1;
    }

};

GpgSignKeyEditInteractor::Private::Private()
    :
    started(false),
    options(0),
    userIDs(),
    currentId(),
    nextId(),
    checkLevel(0)
{
}

GpgSignKeyEditInteractor::GpgSignKeyEditInteractor()
    : EditInteractor(), d(new Private)
{

}

GpgSignKeyEditInteractor::~GpgSignKeyEditInteractor()
{
    delete d;
}

// work around --enable-final
namespace GpgSignKeyEditInteractor_Private
{
enum SignKeyState {
    START = EditInteractor::StartState,
    COMMAND,
    UIDS_ANSWER_SIGN_ALL,
    UIDS_LIST_SEPARATELY,
    // all these free slots belong to UIDS_LIST_SEPARATELY, too
    // (we increase state() by one for each UID, so that action() is called)
    UIDS_LIST_SEPARATELY_DONE = 1000000,
    SET_EXPIRE,
    SET_CHECK_LEVEL,
    SET_TRUST_VALUE,
    SET_TRUST_DEPTH,
    SET_TRUST_REGEXP,
    CONFIRM,
    QUIT,
    SAVE,
    ERROR = EditInteractor::ErrorState
};

typedef std::map<tuple<SignKeyState, unsigned int, std::string>, SignKeyState> TransitionMap;

}

static const char *answer(bool b)
{
    return b ? "Y" : "N";
}

static GpgSignKeyEditInteractor_Private::TransitionMap makeTable()
{
    using namespace GpgSignKeyEditInteractor_Private;
    TransitionMap tab;
    const unsigned int GET_BOOL = GPGME_STATUS_GET_BOOL;
    const unsigned int GET_LINE = GPGME_STATUS_GET_LINE;
#define addEntry( s1, status, str, s2 ) tab[make_tuple( s1, status, str)] = s2
    addEntry(START, GET_LINE, "keyedit.prompt", COMMAND);
    addEntry(COMMAND, GET_BOOL, "keyedit.sign_all.okay", UIDS_ANSWER_SIGN_ALL);
    addEntry(COMMAND, GET_BOOL, "sign_uid.okay", CONFIRM);
    addEntry(UIDS_ANSWER_SIGN_ALL, GET_BOOL, "sign_uid.okay", CONFIRM);
    addEntry(UIDS_ANSWER_SIGN_ALL, GET_LINE, "sign_uid.expire", SET_EXPIRE);
    addEntry(UIDS_ANSWER_SIGN_ALL, GET_LINE, "sign_uid.class", SET_CHECK_LEVEL);
    addEntry(SET_TRUST_VALUE, GET_LINE, "trustsign_prompt.trust_depth", SET_TRUST_DEPTH);
    addEntry(SET_TRUST_DEPTH, GET_LINE, "trustsign_prompt.trust_regexp", SET_TRUST_REGEXP);
    addEntry(SET_TRUST_REGEXP, GET_LINE, "sign_uid.okay", CONFIRM);
    addEntry(SET_CHECK_LEVEL, GET_BOOL, "sign_uid.okay", CONFIRM);
    addEntry(SET_EXPIRE, GET_BOOL, "sign_uid.class", SET_CHECK_LEVEL);
    addEntry(CONFIRM, GET_BOOL, "sign_uid.local_promote_okay", CONFIRM);
    addEntry(CONFIRM, GET_BOOL, "sign_uid.okay", CONFIRM);
    addEntry(CONFIRM, GET_LINE, "keyedit.prompt", COMMAND);
    addEntry(CONFIRM, GET_LINE, "trustsign_prompt.trust_value", SET_TRUST_VALUE);
    addEntry(CONFIRM, GET_LINE, "sign_uid.expire", SET_EXPIRE);
    addEntry(CONFIRM, GET_LINE, "sign_uid.class", SET_CHECK_LEVEL);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_BOOL, "sign_uid.local_promote_okay", CONFIRM);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_LINE, "keyedit.prompt", COMMAND);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_LINE, "trustsign_prompt.trust_value", SET_TRUST_VALUE);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_LINE, "sign_uid.expire", SET_EXPIRE);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_LINE, "sign_uid.class", SET_CHECK_LEVEL);
    addEntry(UIDS_LIST_SEPARATELY_DONE, GET_BOOL, "sign_uid.okay", CONFIRM);
    addEntry(CONFIRM, GET_LINE, "keyedit.prompt", QUIT);
    addEntry(ERROR, GET_LINE, "keyedit.prompt", QUIT);
    addEntry(QUIT, GET_BOOL, "keyedit.save.okay", SAVE);
#undef addEntry
    return tab;
}

const char *GpgSignKeyEditInteractor::action(Error &err) const
{
    static const char check_level_strings[][2] = { "0", "1", "2", "3" };
    using namespace GpgSignKeyEditInteractor_Private;
    using namespace std;

    switch (const unsigned int st = state()) {
    case COMMAND:
        return d->command();
    case UIDS_ANSWER_SIGN_ALL:
        return answer(d->signAll());
    case UIDS_LIST_SEPARATELY_DONE:
        return d->command();
    case SET_EXPIRE:
        return answer(true);
    case SET_TRUST_VALUE:
    // TODO
    case SET_TRUST_DEPTH:
    //TODO
    case SET_TRUST_REGEXP:
        //TODO
        return 0;
    case SET_CHECK_LEVEL:
        return check_level_strings[d->checkLevel];
    case CONFIRM:
        return answer(true);
    case QUIT:
        return "quit";
    case SAVE:
        return answer(true);
    default:
        if (st >= UIDS_LIST_SEPARATELY && st < UIDS_LIST_SEPARATELY_DONE) {
            std::stringstream ss;
            ss << d->nextUserID();
            d->scratch = ss.str();
            return d->scratch.c_str();
        }
    // fall through
    case ERROR:
        err = Error::fromCode(GPG_ERR_GENERAL);
        return 0;
    }
}

unsigned int GpgSignKeyEditInteractor::nextState(unsigned int status, const char *args, Error &err) const
{
    d->started = true;
    using namespace GpgSignKeyEditInteractor_Private;
    static const Error GENERAL_ERROR = Error::fromCode(GPG_ERR_GENERAL);
    //static const Error INV_TIME_ERROR = Error::fromCode( GPG_ERR_INV_TIME );
    static const TransitionMap table(makeTable());
    if (needsNoResponse(status)) {
        return state();
    }

    using namespace GpgSignKeyEditInteractor_Private;

    //lookup transition in map
    const TransitionMap::const_iterator it = table.find(boost::make_tuple(static_cast<SignKeyState>(state()), status, std::string(args)));
    if (it != table.end()) {
        return it->second;
    }

    //handle cases that cannot be handled via the map
    switch (const unsigned int st = state()) {
    case UIDS_ANSWER_SIGN_ALL:
        if (status == GPGME_STATUS_GET_LINE &&
                strcmp(args, "keyedit.prompt") == 0) {
            if (!d->signAll()) {
                return UIDS_LIST_SEPARATELY;
            }
            err = Error::fromCode(GPG_ERR_UNUSABLE_PUBKEY);
            return ERROR;
        }
        break;
    default:
        if (st >= UIDS_LIST_SEPARATELY && st < UIDS_LIST_SEPARATELY_DONE) {
            if (status == GPGME_STATUS_GET_LINE &&
                    strcmp(args, "keyedit.prompt") == 0) {
                return d->allUserIDsListed() ? UIDS_LIST_SEPARATELY_DONE : st + 1 ;
            }
        }
        break;
    case CONFIRM:
    case ERROR:
        err = lastError();
        return ERROR;
    }

    err = GENERAL_ERROR;
    return ERROR;
}

void GpgSignKeyEditInteractor::setCheckLevel(unsigned int checkLevel)
{
    assert(!d->started);
    assert(checkLevel <= 3);
    d->checkLevel = checkLevel;
}

void GpgSignKeyEditInteractor::setUserIDsToSign(const std::vector<unsigned int> &userIDsToSign)
{
    assert(!d->started);
    d->userIDs = userIDsToSign;
    d->nextId = d->userIDs.begin();
    d->currentId = d->userIDs.end();

}
void GpgSignKeyEditInteractor::setSigningOptions(int options)
{
    assert(!d->started);
    d->options = options;
}