New command line parser

A new, more flexible and restrictive parser to improve the
usage and experience of Flameshot in the command line.
This parser is based on a parent-child node model and is very easy
to define relationships between arguments and options with
informative error checking. You can define lambdas to check the
received values for every option and custom error messages

src/cli/commandoption.h

@@ -0,0 +1,68 @@
+// Copyright 2017 Alejandro Sirgo Rica
+//
+// This file is part of Flameshot.
+//
+//     Flameshot 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.
+//
+//     Flameshot 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 Flameshot.  If not, see <http://www.gnu.org/licenses/>.
+
+#ifndef COMMANDOPTION_H
+#define COMMANDOPTION_H
+
+#include <QStringList>
+#include <functional>
+
+using std::function;
+
+class CommandOption
+{
+public:
+    CommandOption(const QString &name, const QString &description,
+                  const QString &valueName = QString(),
+                  const QString &defaultValue = QString());
+
+    CommandOption(const QStringList &names, const QString &description,
+                  const QString &valueName = QString(),
+                  const QString &defaultValue = QString());
+
+    void setName(const QString &name);
+    void setNames(const QStringList &names);
+    QStringList names() const;
+
+    void setValueName(const QString &name);
+    QString valueName() const;
+
+    void setValue(const QString &value);
+    QString value() const;
+
+    void addChecker(const function<bool(QString const&)> checker, const QString &errMsg);
+    bool checkValue(const QString &value) const;
+
+    QString description() const;
+    void setDescription(const QString &description);
+
+    QString errorMsg() const;
+
+    bool operator==(const CommandOption &option) const;
+
+private:
+    QStringList m_names;
+    QString m_description;
+    QString m_valueName;
+    QString m_value;
+
+    function<bool(QString const&)> m_checker;
+    QString m_errorMsg;
+
+};
+
+#endif // COMMANDOPTION_H