/*
  This file is part of Anastasis
  Copyright (C) 2020 Taler Systems SA

  Anastasis is free software; you can redistribute it and/or modify it under the
  terms of the GNU Lesser General Public License as published by the Free Software
  Foundation; either version 3, or (at your option) any later version.

  Anastasis 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
  Anastasis; see the file COPYING.GPL.  If not, see <http://www.gnu.org/licenses/>
*/
/**
 * @file include/anastasis_json.h
 * @brief anastasis de-/serialization api
 * @author Christian Grothoff
 * @author Dominik Meister
 * @author Dennis Neufeld
 */
#ifndef ANASTASIS_JSON_H
#define ANASTASIS_JSON_H

#include <jansson.h>
#include <gnunet/gnunet_util_lib.h>
#include "anastasis_error_codes.h"

/**
 * Enumeration of possible backup process status.
 */
enum ANASTASIS_BackupStatus
{
  ANASTASIS_BS_INITIAL,
  ANASTASIS_BS_SELECT_CONTINENT,
  ANASTASIS_BS_SELECT_COUNTRY,
  ANASTASIS_BS_ENTER_USER_ATTRIBUTES,
  ANASTASIS_BS_ADD_AUTHENTICATION_METHOD,
  ANASTASIS_BS_ADD_POLICY,
  ANASTASIS_BS_PAY
};

/**
 * Enumeration of possible recovery process status.
 */
enum ANASTASIS_RecoveryStatus
{
  ANASTASIS_RS_INITIAL,
  ANASTASIS_RS_SELECT_CONTINENT,
  ANASTASIS_RS_SELECT_COUNTRY,
  ANASTASIS_RS_ENTER_USER_ATTRIBUTES,
  ANASTASIS_RS_SOLVE_CHALLENGE
};

// A state for the backup process.
struct ANASTASIS_BackupState
{
  enum ANASTASIS_BackupStatus status;

  union
  {

    struct
    {
      // empty!
    } select_continent;

    struct
    {
      const char *continent;
    } select_country;

    struct
    {
      const char *continent;
      const char *country;
      const char *currency;       // derived or per manual override!
      json_t *user_attributes;
    } enter_attributes;

    struct
    {
      const char *continent;
      const char *country;
      const char *currency;
      json_t *user_attributes;

      struct AuthenticationDetails
      {
        enum AuthenticationMethod
        {
          SMS,
          VIDEO,
          SECQUEST,
          EMAIL,
          SNAILMAIL
        };
        char *provider_url;
        union Truth
        {

          struct
          {
            char *phone_number;
          } sms;

          struct
          {
            char *question;
            char *answer;             // FIXME: Reasonable to store answer in clear text here?
          } secquest;

          struct
          {
            char *mailaddress;
          } email;

          struct
          {
            char *full_name;
            char *street;             // street name + number
            char *postal_code;
            char *city;
            char *country;
          } snailmail;

          struct
          {
            char *path_to_picture;
          } video;
        } truth;
      }*ad;       // array
      size_t ad_length;
    } add_authentication;
    struct
    {
      const char *continent;
      const char *country;
      const char *currency;
      json_t *user_attributes;

      struct AuthenticationDetails
      {
        enum AuthenticationMethod
        {
          SMS,
          VIDEO,
          SECQUEST,
          EMAIL,
          SNAILMAIL
        };
        char *provider_url;
        union Truth
        {

          struct
          {
            char *phone_number;
          } sms;

          struct
          {
            char *question;
            char *answer;             // FIXME: Reasonable to store answer in clear text here?
          } secquest;

          struct
          {
            char *mailaddress;
          } email;

          struct
          {
            char *full_name;
            char *street;             // street name + number
            char *postal_code;
            char *city;
            char *country;
          } snailmail;

          struct
          {
            char *path_to_picture;
          } video;
        } truth;
      }*ad;       // array
      size_t ad_length;

      struct PolicyDetails
      {
        struct AuthenticationDetails *ad;         // array
      }*pd;       // array
      size_t pd_length;
    } add_policy;
    // FIXME: add_payment
  } details;
};


// A state for the recovery process.
struct ANASTASIS_RecoveryState
{
  enum ANASTASIS_RecoveryStatus status;

  struct
  {
    // empty!
  } select_continent;

  struct
  {
    const char *continent;
  } select_country;

  struct
  {
    const char *continent;
    const char *country;
    const char *currency;         // derived or per manual override!
    json_t *user_attributes;
  } enter_attributes;

  struct
  {
    const char *continent;
    const char *country;
    const char *currency;
    json_t *user_attributes;

    struct ChallengeDetails
    {
      enum AuthenticationMethod
      {
        SMS,
        VIDEO,
        SECQUEST,
        EMAIL,
        SNAILMAIL
      };
      char *provider_url;
      union Challenge
      {

        struct
        {
          char *phone_number;
          char *code;
        } sms;

        struct
        {
          char *question;
          char *answer;             // FIXME: Reasonable to store answer in clear text here?
        } secquest;

        struct
        {
          char *mailaddress;
          char *code;
        } email;

        struct
        {
          char *full_name;
          char *street;             // street name + number
          char *postal_code;
          char *city;
          char *country;
          char *code;
        } snailmail;

        struct
        {
          char *path_to_picture;
          char *code;
        } video;
      } truth;
    }*cd;         // array
    size_t cd_length;
  } solve_challenge;
};

/**
 * Definition of actions on ANASTASIS_BackupState.
 */
struct ANASTASIS_BackupAction
{
  enum action
  {
    ANASTASIS_BA_GET_SELECT_CONTINENT,
    ANASTASIS_BA_GET_SELECT_COUNTRY,
    ANASTASIS_BA_GET_ENTER_USER_ATTRIBUTES,
    ANASTASIS_BA_GET_ADD_AUTHENTICATION_METHOD,
    ANASTASIS_BA_GET_ADD_POLICY,
    ANASTASIS_BA_GET_PAY,
    ANASTASIS_BA_SET_SELECT_CONTINENT,
    ANASTASIS_BA_SET_SELECT_COUNTRY,
    ANASTASIS_BA_SET_ENTER_USER_ATTRIBUTES,
    ANASTASIS_BA_SET_ADD_AUTHENTICATION_METHOD,
    ANASTASIS_BA_SET_ADD_POLICY,
    ANASTASIS_BA_SET_PAY
  };
};

/**
 * Definition of actions on ANASTASIS_RecoveryState.
 */
struct ANASTASIS_RecoveryAction
{
  enum action
  {
    ANASTASIS_RS_GET_SELECT_CONTINENT,
    ANASTASIS_RS_GET_SELECT_COUNTRY,
    ANASTASIS_RS_GET_ENTER_USER_ATTRIBUTES,
    ANASTASIS_RS_GET_SOLVE_CHALLENGE,
    ANASTASIS_RS_SET_SELECT_CONTINENT,
    ANASTASIS_RS_SET_SELECT_COUNTRY,
    ANASTASIS_RS_SET_ENTER_USER_ATTRIBUTES,
    ANASTASIS_RS_SET_SOLVE_CHALLENGE
  };
};


/**
 * Signature of the callback bassed to #ANASTASIS_apply_anastasis_backup_action
 * for asynchronous actions on a #ANASTASIS_BackupState.
 *
 * @param cls closure
 * @param new_bs the new #ANASTASIS_BackupState
 * @param error error code
 */
typedef void
(*ANASTASIS_BackupApplyActionCallback)(
  void *cls,
  const struct ANASTASIS_BackupState *new_bs,
  enum TALER_ErrorCode error);


/**
 * Signature of the callback bassed to #ANASTASIS_apply_anastasis_recovery_action
 * for asynchronous actions on a #ANASTASIS_RecoveryState.
 *
 * @param cls closure
 * @param new_bs the new #ANASTASIS_RecoveryState
 * @param error error code
 */
typedef void
(*ANASTASIS_RecoveryApplyActionCallback)(
  void *cls,
  const struct ANASTASIS_RecoveryState *new_rs,
  enum TALER_ErrorCode error);


/**
 * Returns an initial ANASTASIS_BackupState.
 *
 * @return initial ANASTASIS_BackupState
 */
struct ANASTASIS_BackupState *
ANASTASIS_get_initial_backup_state ();


/**
 * Returns an initial ANASTASIS_RecoveryState.
 *
 * @return initial ANASTASIS_RecoveryState
 */
struct ANASTASIS_RecoveryState *
ANASTASIS_get_initial_recovery_state ();


/**
 * Operates on a backup state depending on given #ANASTASIS_BackupState
 * and #ANASTASIS_BackupAction. The new #ANASTASIS_BackupState is returned
 * by a callback function.
 * This function can do network access to talk to anastasis service providers.
 *
 * @param ctx url context for the event loop
 * @param bs the previous *ANASTASIS_BackupState
 * @param ba the action to do on #ANASTASIS_BackupState
 * @param cb callback function to call with the action
 */
void
ANASTASIS_apply_anastasis_backup_action (
  struct GNUNET_CURL_Context *ctx,
  struct ANASTASIS_BackupState *bs,
  struct ANASTASIS_BackupAction *ba,
  ANASTASIS_BackupApplyActionCallback cb);


/**
 * Operates on a recovery state depending on given #ANASTASIS_RecoveryState
 * and #ANASTASIS_RecoveryAction. The new #ANASTASIS_RecoveryState is returned
 * by a callback function.
 * This function can do network access to talk to anastasis service providers.
 *
 * @param ctx url context for the event loop
 * @param bs the previous *ANASTASIS_RecoveryState
 * @param ba the action to do on #ANASTASIS_RecoveryState
 * @param cb callback function to call with the action
 */
void
ANASTASIS_apply_anastasis_recovery_action (
  struct GNUNET_CURL_Context *ctx,
  struct ANASTASIS_RecoveryState *rs,
  struct ANASTASIS_RecoveryAction *ra,
  ANASTASIS_RecoveryApplyActionCallback cb);

#endif  /* _ANASTASIS_JSON_H */