/*
    Copyright 2015-2016 Amebis
    Copyright 2016 GÉANT

    This file is part of GÉANTLink.

    GÉANTLink 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.

    GÉANTLink 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 GÉANTLink. If not, see <http://www.gnu.org/licenses/>.
*/

#include <sal.h>

namespace eap
{
    ///
    /// Base class for method credential storage
    ///
    class credentials;

    ///
    /// Password based method credentials
    ///
    class credentials_pass;
}

#pragma once

#include "Config.h"
#include "Module.h"

#include "../../../include/Version.h"

#include <WinStd/Common.h>

#include <Windows.h>
#include <eaptypes.h> // Must include after <Windows.h>
#include <tchar.h>
#include <wincred.h>

#include <string>


namespace eap
{
    class credentials : public config
    {
    public:
        ///
        /// Credential source when combined
        ///
        enum  source_t {
            source_unknown = -1, ///< Unknown source
            source_cache = 0,    ///< Credentials were obtained from EapHost cache
            source_preshared,    ///< Credentials were set by method configuration
            source_storage       ///< Credentials were loaded from Windows Credential Manager
        };


    public:
        ///
        /// Constructs credentials
        ///
        /// \param[in] mod  EAP module to use for global services
        ///
        credentials(_In_ module &mod);

        ///
        /// Copies credentials
        ///
        /// \param[in] other  Credentials to copy from
        ///
        credentials(_In_ const credentials &other);

        ///
        /// Moves credentials
        ///
        /// \param[in] other  Credentials to move from
        ///
        credentials(_Inout_ credentials &&other);

        ///
        /// Copies credentials
        ///
        /// \param[in] other  Credentials to copy from
        ///
        /// \returns Reference to this object
        ///
        credentials& operator=(_In_ const credentials &other);

        ///
        /// Moves credentials
        ///
        /// \param[in] other  Configuration to move from
        ///
        /// \returns Reference to this object
        ///
        credentials& operator=(_Inout_ credentials &&other);

        ///
        /// Resets credentials
        ///
        virtual void clear();

        ///
        /// Test credentials if blank
        ///
        /// \returns
        /// - \c true if blank
        /// - \c false otherwise
        ///
        virtual bool empty() const;

        /// \name XML configuration management
        /// @{

        ///
        /// Save to XML document
        ///
        /// \param[in]  pDoc         XML document
        /// \param[in]  pConfigRoot  Suggested root element for saving
        ///
        virtual void save(_In_ IXMLDOMDocument *pDoc, _In_ IXMLDOMNode *pConfigRoot) const;

        ///
        /// Load from XML document
        ///
        /// \param[in]  pConfigRoot  Root element for loading
        ///
        virtual void load(_In_ IXMLDOMNode *pConfigRoot);

        /// @}

        /// \name BLOB management
        /// @{

        ///
        /// Packs a configuration
        ///
        /// \param[inout] cursor  Memory cursor
        ///
        virtual void operator<<(_Inout_ cursor_out &cursor) const;

        ///
        /// Returns packed size of a configuration
        ///
        /// \returns Size of data when packed (in bytes)
        ///
        virtual size_t get_pk_size() const;

        ///
        /// Unpacks a configuration
        ///
        /// \param[inout] cursor  Memory cursor
        ///
        virtual void operator>>(_Inout_ cursor_in &cursor);

        /// @}

        /// \name Storage
        /// @{

        ///
        /// Save credentials to Windows Credential Manager
        ///
        /// \param[in]  pszTargetName  The name in Windows Credential Manager to store credentials as
        ///
        virtual void store(_In_z_ LPCTSTR pszTargetName) const = 0;

        ///
        /// Retrieve credentials from Windows Credential Manager
        ///
        /// \param[in]  pszTargetName  The name in Windows Credential Manager to retrieve credentials from
        ///
        virtual void retrieve(_In_z_ LPCTSTR pszTargetName) = 0;

        ///
        /// Returns target name for Windows Credential Manager credential name
        ///
        /// \param[in]  pszTargetName  The name in Windows Credential Manager to retrieve credentials from
        ///
        /// \returns Final target name to store/retrieve credentials in Windows Credential Manager
        ///
        inline winstd::tstring target_name(_In_z_ LPCTSTR pszTargetName) const
        {
            winstd::tstring target_name(_T(PRODUCT_NAME_STR) _T("/"));
            target_name += pszTargetName;
            target_name += _T('/');
            target_name += target_suffix();
            assert(target_name.length() < CRED_MAX_GENERIC_TARGET_NAME_LENGTH);
            return target_name;
        }

        ///
        /// Return target suffix for Windows Credential Manager credential name
        ///
        virtual LPCTSTR target_suffix() const = 0;

        /// @}

        ///
        /// Returns credential identity.
        ///
        virtual std::wstring get_identity() const;

        ///
        /// Returns credential name (for GUI display).
        ///
        virtual winstd::tstring get_name() const;

    public:
        std::wstring m_identity;    ///< Identity (username\@domain, certificate name etc.)
    };


    class credentials_pass : public credentials
    {
    public:
        ///
        /// Constructs credentials
        ///
        /// \param[in] mod  EAP module to use for global services
        ///
        credentials_pass(_In_ module &mod);

        ///
        /// Copies credentials
        ///
        /// \param[in] other  Credentials to copy from
        ///
        credentials_pass(_In_ const credentials_pass &other);

        ///
        /// Moves credentials
        ///
        /// \param[in] other  Credentials to move from
        ///
        credentials_pass(_Inout_ credentials_pass &&other);

        ///
        /// Copies credentials
        ///
        /// \param[in] other  Credentials to copy from
        ///
        /// \returns Reference to this object
        ///
        credentials_pass& operator=(_In_ const credentials_pass &other);

        ///
        /// Moves credentials
        ///
        /// \param[in] other  Credentials to move from
        ///
        /// \returns Reference to this object
        ///
        credentials_pass& operator=(_Inout_ credentials_pass &&other);

        ///
        /// Resets credentials
        ///
        virtual void clear();

        ///
        /// Test credentials if blank
        ///
        /// \returns
        /// - \c true if blank
        /// - \c false otherwise
        ///
        virtual bool empty() const;

        /// \name XML configuration management
        /// @{

        ///
        /// Save to XML document
        ///
        /// \param[in]  pDoc         XML document
        /// \param[in]  pConfigRoot  Suggested root element for saving
        ///
        virtual void save(_In_ IXMLDOMDocument *pDoc, _In_ IXMLDOMNode *pConfigRoot) const;

        ///
        /// Load from XML document
        ///
        /// \param[in]  pConfigRoot  Root element for loading
        ///
        virtual void load(_In_ IXMLDOMNode *pConfigRoot);

        /// @}

        /// \name BLOB management
        /// @{

        ///
        /// Packs a configuration
        ///
        /// \param[inout] cursor  Memory cursor
        ///
        virtual void operator<<(_Inout_ cursor_out &cursor) const;

        ///
        /// Returns packed size of a configuration
        ///
        /// \returns Size of data when packed (in bytes)
        ///
        virtual size_t get_pk_size() const;

        ///
        /// Unpacks a configuration
        ///
        /// \param[inout] cursor  Memory cursor
        ///
        virtual void operator>>(_Inout_ cursor_in &cursor);

        /// @}

        /// \name Storage
        /// @{

        ///
        /// Save credentials to Windows Credential Manager
        ///
        /// \param[in]  pszTargetName  The name in Windows Credential Manager to store credentials as
        ///
        virtual void store(_In_z_ LPCTSTR pszTargetName) const;

        ///
        /// Retrieve credentials from Windows Credential Manager
        ///
        /// \param[in]  pszTargetName  The name in Windows Credential Manager to retrieve credentials from
        ///
        virtual void retrieve(_In_z_ LPCTSTR pszTargetName);

        /// @}

    public:
        winstd::sanitizing_wstring m_password;  ///< Password

    private:
        /// \cond internal
        static const unsigned char s_entropy[1024];
        /// \endcond
    };
}
