/* vi: set sw=4 ts=4:
 *
 * Copyright (C) 2001 - 2014 Christian Hohnstaedt.
 *
 * All rights reserved.
 */

/* here we have the possibility to add our own OIDS */

#include <openssl/objects.h>
#include <QStringList>
#include <QStandardPaths>
#include <QRegularExpression>
#include <QDebug>
#include <QDir>
#include "func.h"
#include "oid.h"
#include "XcaWarningCore.h"

int first_additional_oid = 0;

NIDlist extkeyuse_nid;
NIDlist distname_nid;

QMap<QString,const char*> oid_name_clash;
QMap<QString,int> oid_lower_map;

static QStringList searchdirs()
{
	QStringList dirs = QStandardPaths::standardLocations(
				QStandardPaths::AppDataLocation);
#ifdef INSTALL_DATA_PREFIX
	dirs << QString(INSTALL_DATA_PREFIX);
#endif
	return dirs;
}

static void addToLowerMap(int nid)
{
	QString n = OBJ_nid2sn(nid);
	QString l = n.toLower();

	if (n != l)
		oid_lower_map[l] = nid;
	n = OBJ_nid2ln(nid);
	l = n.toLower();
	if (n != l)
		oid_lower_map[l] = nid;
}

/* reads additional OIDs from a file: oid, sn, ln */
static void insert_new_oid(const QStringList &sl, QString fname, int line)
{
	bool differs = false;
	QByteArray in_use, oid, sn, ln;

	if (sl.count() != 3) {
		XCA_WARN(QObject::tr("Error reading config file %1 at line %2")
			.arg(fname).arg(line));
		return;
	}
	oid = sl[0].toLatin1();
	sn = sl[1].toLatin1();
	ln = sl[2].toLatin1();

	int nid = OBJ_txt2nid(oid.constData());
	if (nid != NID_undef) {
		/* OID already known by OpenSSL */
		if (sn != OBJ_nid2sn(nid)) {
			/* ... but with a different ShortName */
			qWarning() << "OID: " << oid << "SN differs: " << sn <<
				" " << OBJ_nid2sn(nid);
			oid_name_clash[sn] = OBJ_nid2sn(nid);
			differs = true;
		}
		if (ln != OBJ_nid2ln(nid)) {
			/* ... but with a different LongName */
			qWarning() << "OID: " << oid << "LN differs: " << ln <<
				" " << OBJ_nid2ln(nid);
			oid_name_clash[ln] = OBJ_nid2ln(nid);
			differs = true;
		}
	} else {
		/* Check whether ShortName or LongName are already in use
		 * for a different OID */
		if (OBJ_txt2nid(sn.constData()) != NID_undef)
			in_use = sn;
		if (OBJ_txt2nid(ln.constData()) != NID_undef)
			in_use = ln;
	}
	ign_openssl_error();
	if (differs) {
		/* OID exists with different SN or LN. The differing names
		 * are added as "alias" in "oid_name_clash" used when loading
		 * dn.txt and eku.txt */
		XCA_WARN(QObject::tr("The Object '%1' from file %2 line %3 is already known as '%4:%5:%6' and should be removed.")
			.arg(sl.join(":")).arg(fname).arg(line)
			.arg(OBJ_obj2QString(OBJ_nid2obj(nid), 1))
			.arg(OBJ_nid2sn(nid)).arg(OBJ_nid2ln(nid))
		);
	} else if (!in_use.isEmpty()) {
		/* OID does not exist, but SN or LN however do.
		 * Do NOT create OID and tell the user about */
		nid = OBJ_txt2nid(in_use.constData());
		XCA_WARN(QObject::tr("The identifier '%1' for OID %2 from file %3 line %4 is already used for a different OID as '%5:%6:%7' and should be changed to avoid conflicts.")
			.arg(in_use.constData())
			.arg(oid.constData())
			.arg(fname).arg(line)
			.arg(OBJ_obj2QString(OBJ_nid2obj(nid), 1))
			.arg(OBJ_nid2sn(nid)).arg(OBJ_nid2ln(nid))
		);
	} else if (nid == NID_undef) {
		nid=OBJ_create(oid.constData(), sn.constData(), ln.constData());
		qDebug() << "Creating OID:" << fname << line <<
						nid << oid << sn << ln;
		try {
			openssl_error();
			addToLowerMap(nid);
		} catch (errorEx &e) {
			errorEx err(errorEx(e.getString() +
				QString("%1:%2 OID: %3")
				.arg(fname).arg(line).arg(oid.constData())));
			XCA_ERROR(err);
		}
	}
}

static void readOIDs(const QString &fname)
{
	int line = 0;
	QFile file(fname);
	if (!file.open(QIODevice::ReadOnly))
		return;
	qDebug() << "Read additional OIDs from" << fname;
	QTextStream in(&file);
	while (!in.atEnd()) {
		QString entry = in.readLine().trimmed();
		line++;
		if (entry.startsWith('#') || entry.isEmpty())
			continue;
		insert_new_oid(entry.split(QRegularExpression("\\s*:\\s*")),
									fname, line);
	}
}

/* reads a list of OIDs/SNs from a file and turns them into a QValueList
 * of integers, representing the NIDs. Usually to be used by NewX509 for
 * the list of ExtendedKeyUsage and Distinguished Name
 */
static NIDlist readNIDlist(const QString &fname)
{
	int line = 0, nid;
	NIDlist nl;
	QFile file(fname);
	if (!file.open(QIODevice::ReadOnly))
                return nl;

	QTextStream in(&file);
	while (!in.atEnd()) {
		const char *userdefined;
		QString entry = in.readLine().trimmed();
		line++;
		if (entry.startsWith('#') || entry.isEmpty())
			continue;
		userdefined = oid_name_clash[entry];
		if (userdefined)
			entry = userdefined;
		nid = OBJ_txt2nid(CCHAR(entry));
		if (nid == NID_undef)
			XCA_WARN(QObject::tr("Unknown object '%1' in file %2 line %3")
				.arg(entry).arg(fname).arg(line));
		else
			nl += nid;
	}
	openssl_error();
	return nl;
}

/* creates a new nid list from the given filename */
static NIDlist read_nidlist(const QString &name)
{
	NIDlist nl;

	foreach(QString d, searchdirs())
	{
		nl = readNIDlist(d + "/" + name);
		qDebug() << "Read" << nl.count() << "NIDs from"
				 << d + "/" + name;
		if (nl.count() > 0)
			break;
	}
	return nl;
}

void initOIDs()
{
	first_additional_oid = OBJ_new_nid(0);
	openssl_error();
	for (int i=0; i<first_additional_oid;i++)
		addToLowerMap(i);
	ign_openssl_error();

	foreach(QString d, searchdirs())
		readOIDs(d + "/oids.txt");

	extkeyuse_nid = read_nidlist("eku.txt");
	distname_nid = read_nidlist("dn.txt");

	openssl_error();
}