/*
  This file is part of TALER
  (C) 2022-2024 Taler Systems SA

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

  TALER 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 TALER; see the file COPYING.  If not,
  see <http://www.gnu.org/licenses/>
*/

/**
 * @file taler-merchant-httpd_private-post-templates.c
 * @brief implementing POST /templates request handling
 * @author Priscilla HUANG
 */
#include "platform.h"
#include "taler-merchant-httpd_private-post-templates.h"
#include "taler-merchant-httpd_helper.h"
#include <taler/taler_json_lib.h>


/**
 * Check if the two templates are identical.
 *
 * @param t1 template to compare
 * @param t2 other template to compare
 * @return true if they are 'equal', false if not or of payto_uris is not an array
 */
static bool
templates_equal (const struct TALER_MERCHANTDB_TemplateDetails *t1,
                 const struct TALER_MERCHANTDB_TemplateDetails *t2)
{
  return ( (0 == strcmp (t1->template_description,
                         t2->template_description)) &&
           ( ( (NULL == t1->otp_id) &&
               (NULL == t2->otp_id) ) ||
             ( (NULL != t1->otp_id) &&
               (NULL != t2->otp_id) &&
               (0 == strcmp (t1->otp_id,
                             t2->otp_id))) ) &&
           ( ( (NULL == t1->required_currency) &&
               (NULL == t2->required_currency) ) ||
             ( (NULL != t1->required_currency) &&
               (NULL != t2->required_currency) &&
               (0 == strcmp (t1->required_currency,
                             t2->required_currency))) ) &&
           ( ( (NULL == t1->editable_defaults) &&
               (NULL == t2->editable_defaults) ) ||
             ( (NULL != t1->editable_defaults) &&
               (NULL != t2->editable_defaults) &&
               (1 == json_equal (t1->editable_defaults,
                                 t2->editable_defaults))) ) &&
           (1 == json_equal (t1->template_contract,
                             t2->template_contract)) );
}


MHD_RESULT
TMH_private_post_templates (const struct TMH_RequestHandler *rh,
                            struct MHD_Connection *connection,
                            struct TMH_HandlerContext *hc)
{
  struct TMH_MerchantInstance *mi = hc->instance;
  struct TALER_MERCHANTDB_TemplateDetails tp = { 0 };
  const char *template_id;
  enum GNUNET_DB_QueryStatus qs;
  struct GNUNET_JSON_Specification spec[] = {
    GNUNET_JSON_spec_string ("template_id",
                             &template_id),
    GNUNET_JSON_spec_string ("template_description",
                             (const char **) &tp.template_description),
    GNUNET_JSON_spec_mark_optional (
      GNUNET_JSON_spec_string ("otp_id",
                               (const char **) &tp.otp_id),
      NULL),
    GNUNET_JSON_spec_json ("template_contract",
                           &tp.template_contract),
    GNUNET_JSON_spec_mark_optional (
      GNUNET_JSON_spec_string ("required_currency",
                               (const char **) &tp.required_currency),
      NULL),
    GNUNET_JSON_spec_mark_optional (
      GNUNET_JSON_spec_json ("editable_defaults",
                             &tp.editable_defaults),
      NULL),
    GNUNET_JSON_spec_end ()
  };
  uint64_t otp_serial = 0;

  GNUNET_assert (NULL != mi);
  {
    enum GNUNET_GenericReturnValue res;

    res = TALER_MHD_parse_json_data (connection,
                                     hc->request_body,
                                     spec);
    if (GNUNET_OK != res)
    {
      GNUNET_break_op (0);
      return (GNUNET_NO == res)
             ? MHD_YES
             : MHD_NO;
    }
  }
  if (! TMH_template_contract_valid (tp.template_contract))
  {
    GNUNET_break_op (0);
    json_dumpf (tp.template_contract,
                stderr,
                JSON_INDENT (2));
    GNUNET_JSON_parse_free (spec);
    return TALER_MHD_reply_with_error (connection,
                                       MHD_HTTP_BAD_REQUEST,
                                       TALER_EC_GENERIC_PARAMETER_MALFORMED,
                                       "template_contract");
  }

  if ( (NULL != tp.required_currency) &&
       (GNUNET_OK !=
        TALER_check_currency (tp.required_currency)) )
  {
    GNUNET_break_op (0);
    GNUNET_JSON_parse_free (spec);
    return TALER_MHD_reply_with_error (connection,
                                       MHD_HTTP_BAD_REQUEST,
                                       TALER_EC_GENERIC_PARAMETER_MALFORMED,
                                       "required_currency");
  }
  if ( (NULL != tp.required_currency) &&
       (NULL != json_object_get (tp.template_contract,
                                 "amount")) )
  {
    GNUNET_break_op (0);
    GNUNET_JSON_parse_free (spec);
    return TALER_MHD_reply_with_error (connection,
                                       MHD_HTTP_BAD_REQUEST,
                                       TALER_EC_GENERIC_PARAMETER_MALFORMED,
                                       "required_currency and contract::amount specified");
  }
  if (NULL != tp.editable_defaults)
  {
    const char *key;
    json_t *val;

    json_object_foreach (tp.editable_defaults, key, val)
    {
      if (NULL !=
          json_object_get (tp.template_contract,
                           key))
      {
        char *msg;
        MHD_RESULT ret;

        GNUNET_break_op (0);
        GNUNET_asprintf (&msg,
                         "editable_defaults::%s conflicts with template_contract",
                         key);
        GNUNET_JSON_parse_free (spec);
        ret = TALER_MHD_reply_with_error (connection,
                                          MHD_HTTP_BAD_REQUEST,
                                          TALER_EC_GENERIC_PARAMETER_MALFORMED,
                                          msg);
        GNUNET_free (msg);
        return ret;
      }
    }
  }

  if (NULL != tp.otp_id)
  {
    qs = TMH_db->select_otp_serial (TMH_db->cls,
                                    mi->settings.id,
                                    tp.otp_id,
                                    &otp_serial);
    switch (qs)
    {
    case GNUNET_DB_STATUS_HARD_ERROR:
    case GNUNET_DB_STATUS_SOFT_ERROR:
      GNUNET_break (0);
      GNUNET_JSON_parse_free (spec);
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_GENERIC_DB_STORE_FAILED,
                                         "select_otp_serial");
    case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
      GNUNET_JSON_parse_free (spec);
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_NOT_FOUND,
                                         TALER_EC_MERCHANT_GENERIC_OTP_DEVICE_UNKNOWN,
                                         NULL);
    case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
      break;
    }
  }

  qs = TMH_db->insert_template (TMH_db->cls,
                                mi->settings.id,
                                template_id,
                                otp_serial,
                                &tp);
  switch (qs)
  {
  case GNUNET_DB_STATUS_HARD_ERROR:
  case GNUNET_DB_STATUS_SOFT_ERROR:
    GNUNET_break (0);
    GNUNET_JSON_parse_free (spec);
    return TALER_MHD_reply_with_error (connection,
                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
                                       TALER_EC_GENERIC_DB_STORE_FAILED,
                                       NULL);
  case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
    GNUNET_JSON_parse_free (spec);
    return TALER_MHD_reply_static (connection,
                                   MHD_HTTP_NO_CONTENT,
                                   NULL,
                                   NULL,
                                   0);
  case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
    break;
  }

  {
    /* Test if a template of this id is known */
    struct TALER_MERCHANTDB_TemplateDetails etp;

    qs = TMH_db->lookup_template (TMH_db->cls,
                                  mi->settings.id,
                                  template_id,
                                  &etp);
    switch (qs)
    {
    case GNUNET_DB_STATUS_HARD_ERROR:
    case GNUNET_DB_STATUS_SOFT_ERROR:
      /* Clean up and fail hard */
      GNUNET_break (0);
      GNUNET_JSON_parse_free (spec);
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_GENERIC_DB_FETCH_FAILED,
                                         NULL);
    case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
      GNUNET_break (0);
      GNUNET_JSON_parse_free (spec);
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_GENERIC_DB_FETCH_FAILED,
                                         "logic error");
    case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
      break;
    }
    /* idempotency check: is etp == tp? */
    {
      bool eq;

      eq = templates_equal (&tp,
                            &etp);
      TALER_MERCHANTDB_template_details_free (&etp);
      TMH_db->rollback (TMH_db->cls);
      GNUNET_JSON_parse_free (spec);
      return eq
        ? TALER_MHD_reply_static (connection,
                                  MHD_HTTP_NO_CONTENT,
                                  NULL,
                                  NULL,
                                  0)
        : TALER_MHD_reply_with_error (connection,
                                      MHD_HTTP_CONFLICT,
                                      TALER_EC_MERCHANT_PRIVATE_POST_TEMPLATES_CONFLICT_TEMPLATE_EXISTS,
                                      template_id);
    }
  }
}


/* end of taler-merchant-httpd_private-post-templates.c */