/*
 This file is part of GNUnet.
 Copyright (C) 2012-2015 GNUnet e.V.

   GNUnet 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 of the License,
   or (at your option) any later version.

   GNUnet 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
   Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */
/**
 * @author Martin Schanzenbach
 * @author Philippe Buschmann
 * @file identity/plugin_rest_identity.c
 * @brief GNUnet Identity REST plugin
 */

#include "platform.h"
#include "gnunet_rest_plugin.h"
#include "gnunet_identity_service.h"
#include "gnunet_rest_lib.h"
#include "microhttpd.h"
#include <jansson.h>

/**
 * Identity Namespace
 */
#define GNUNET_REST_API_NS_IDENTITY "/identity"

/**
 * Identity Namespace with public key specifier
 */
#define GNUNET_REST_API_NS_IDENTITY_ALL "/identity/all"

/**
 * Identity Namespace with public key specifier
 */
#define GNUNET_REST_API_NS_IDENTITY_PUBKEY "/identity/pubkey"

/**
 * Identity Namespace with public key specifier
 */
#define GNUNET_REST_API_NS_IDENTITY_NAME "/identity/name"

/**
 * Identity Subsystem Namespace
 */
#define GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM "/identity/subsystem"

/**
 * Parameter public key
 */
#define GNUNET_REST_IDENTITY_PARAM_PUBKEY "pubkey"

/**
 * Parameter subsystem
 */
#define GNUNET_REST_IDENTITY_PARAM_SUBSYSTEM "subsystem"

/**
 * Parameter name
 */
#define GNUNET_REST_IDENTITY_PARAM_NAME "name"

/**
 * Parameter new name
 */
#define GNUNET_REST_IDENTITY_PARAM_NEWNAME "newname"

/**
 * Error message Unknown Error
 */
#define GNUNET_REST_IDENTITY_ERROR_UNKNOWN "Unknown Error"

/**
 * Error message No identity found
 */
#define GNUNET_REST_IDENTITY_NOT_FOUND "No identity found"

/**
 * Error message Missing identity name
 */
#define GNUNET_REST_IDENTITY_MISSING_NAME "Missing identity name"

/**
 * Error message Missing identity name
 */
#define GNUNET_REST_IDENTITY_MISSING_PUBKEY "Missing identity public key"

/**
 * Error message No data
 */
#define GNUNET_REST_ERROR_NO_DATA "No data"

/**
 * Error message Data invalid
 */
#define GNUNET_REST_ERROR_DATA_INVALID "Data invalid"

/**
 * State while collecting all egos
 */
#define ID_REST_STATE_INIT 0

/**
 * Done collecting egos
 */
#define ID_REST_STATE_POST_INIT 1

/**
 * The configuration handle
 */
const struct GNUNET_CONFIGURATION_Handle *cfg;

/**
 * HTTP methods allows for this plugin
 */
static char* allow_methods;

/**
 * @brief struct returned by the initialization function of the plugin
 */
struct Plugin
{
  const struct GNUNET_CONFIGURATION_Handle *cfg;
};

/**
 * The ego list
 */
struct EgoEntry
{
  /**
   * DLL
   */
  struct EgoEntry *next;

  /**
   * DLL
   */
  struct EgoEntry *prev;

  /**
   * Ego Identifier
   */
  char *identifier;

  /**
   * Public key string
   */
  char *keystring;

  /**
   * The Ego
   */
  struct GNUNET_IDENTITY_Ego *ego;
};

/**
 * The request handle
 */
struct RequestHandle
{
  /**
   * The data from the REST request
   */
  const char* data;

  /**
   * The name to look up
   */
  char *name;

  /**
   * the length of the REST data
   */
  size_t data_size;


  /**
   * Ego list
   */
  struct EgoEntry *ego_head;

  /**
   * Ego list
   */
  struct EgoEntry *ego_tail;

  /**
   * The processing state
   */
  int state;

  /**
   * Handle to Identity service.
   */
  struct GNUNET_IDENTITY_Handle *identity_handle;

  /**
   * IDENTITY Operation
   */
  struct GNUNET_IDENTITY_Operation *op;

  /**
   * Rest connection
   */
  struct GNUNET_REST_RequestHandle *rest_handle;

  /**
   * Desired timeout for the lookup (default is no timeout).
   */
  struct GNUNET_TIME_Relative timeout;

  /**
   * ID of a task associated with the resolution process.
   */
  struct GNUNET_SCHEDULER_Task *timeout_task;

  /**
   * The plugin result processor
   */
  GNUNET_REST_ResultProcessor proc;

  /**
   * The closure of the result processor
   */
  void *proc_cls;

  /**
   * The url
   */
  char *url;

  /**
   * Error response message
   */
  char *emsg;

  /**
   * Response code
   */
  int response_code;

};

/**
 * Cleanup lookup handle
 * @param handle Handle to clean up
 */
static void
cleanup_handle (void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  struct EgoEntry *ego_tmp;

  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Cleaning up\n");
  if (NULL != handle->timeout_task)
  {
    GNUNET_SCHEDULER_cancel (handle->timeout_task);
    handle->timeout_task = NULL;
  }

  if (NULL != handle->url)
    GNUNET_free(handle->url);
  if (NULL != handle->emsg)
    GNUNET_free(handle->emsg);
  if (NULL != handle->name)
    GNUNET_free (handle->name);
  if (NULL != handle->identity_handle)
    GNUNET_IDENTITY_disconnect (handle->identity_handle);

  for (ego_entry = handle->ego_head;
  NULL != ego_entry;)
  {
    ego_tmp = ego_entry;
    ego_entry = ego_entry->next;
    GNUNET_free(ego_tmp->identifier);
    GNUNET_free(ego_tmp->keystring);
    GNUNET_free(ego_tmp);
  }

  GNUNET_free(handle);
}

/**
 * Task run on errors.  Reports an error and cleans up everything.
 *
 * @param cls the `struct RequestHandle`
 */
static void
do_error (void *cls)
{
  struct RequestHandle *handle = cls;
  struct MHD_Response *resp;
  json_t *json_error = json_object();
  char *response;

  if (NULL == handle->emsg)
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_ERROR_UNKNOWN);

  json_object_set_new(json_error,"error", json_string(handle->emsg));

  if (0 == handle->response_code)
    handle->response_code = MHD_HTTP_OK;
  response = json_dumps (json_error, 0);
  resp = GNUNET_REST_create_response (response);
  handle->proc (handle->proc_cls, resp, handle->response_code);
  json_decref(json_error);
  GNUNET_free(response);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
}



/**
 * Get EgoEntry from list with either a public key or a name
 * If public key and name are not NULL, it returns the public key result first
 *
 * @param handle the RequestHandle
 * @param pubkey the public key of an identity (only one can be NULL)
 * @param name the name of an identity (only one can be NULL)
 * @return EgoEntry or NULL if not found
 */
struct EgoEntry*
get_egoentry(struct RequestHandle *handle, char* pubkey, char *name)
{
  struct EgoEntry *ego_entry;
  if (NULL != pubkey)
  {
    for (ego_entry = handle->ego_head;
	NULL != ego_entry;
	ego_entry = ego_entry->next)
    {
      if (0 != strcasecmp (pubkey, ego_entry->keystring))
	continue;
      return ego_entry;
    }
  }
  if (NULL != name)
  {
    for (ego_entry = handle->ego_head;
	NULL != ego_entry;
	ego_entry = ego_entry->next)
    {
      if (0 != strcasecmp (name, ego_entry->identifier))
	continue;
      return ego_entry;
    }
  }
  return NULL;
}


/**
 * Callback for GET Request with subsystem
 *
 * @param cls the RequestHandle
 * @param ego the Ego found
 * @param ctx the context
 * @param name the id of the ego
 */
static void
ego_get_for_subsystem (void *cls,
		       struct GNUNET_IDENTITY_Ego *ego,
		       void **ctx,
		       const char *name)
{
  struct RequestHandle *handle = cls;
  struct MHD_Response *resp;
  struct GNUNET_CRYPTO_EcdsaPublicKey public_key;
  json_t *json_root;
  char *result_str;
  char *public_key_string;

  if(NULL == ego)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  GNUNET_IDENTITY_ego_get_public_key(ego,&public_key);
  public_key_string = GNUNET_CRYPTO_ecdsa_public_key_to_string(&public_key);

  // create json with subsystem identity
  json_root = json_object ();
  json_object_set_new (json_root,
		       GNUNET_REST_IDENTITY_PARAM_PUBKEY,
		       json_string(public_key_string));
  json_object_set_new (json_root,
		       GNUNET_REST_IDENTITY_PARAM_NAME,
		       json_string(name));

  result_str = json_dumps (json_root, 0);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Result %s\n", result_str);
  resp = GNUNET_REST_create_response (result_str);

  json_decref (json_root);
  handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
  GNUNET_free(result_str);
  GNUNET_free(public_key_string);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
}

/**
 * Handle identity GET request for subsystem
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_get_subsystem (struct GNUNET_REST_RequestHandle *con_handle,
		   const char* url,
		   void *cls)
{
  struct RequestHandle *handle = cls;
  char *subsystem;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM) >= strlen (handle->url))
  {
    handle->emsg = GNUNET_strdup("Missing subsystem name");
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  subsystem = &handle->url[strlen (
      GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM) + 1];
  //requested default identity of subsystem
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Looking for %s's ego\n", subsystem);

  handle->op = GNUNET_IDENTITY_get (handle->identity_handle,
				    subsystem,
				    &ego_get_for_subsystem,
				    handle);

  if (NULL == handle->op)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
}


/**
 * Handle identity GET request - responds with all identities
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_get_all (struct GNUNET_REST_RequestHandle *con_handle,
	     const char* url,
	     void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  struct MHD_Response *resp;
  json_t *json_root;
  json_t *json_ego;
  char *result_str;

  json_root = json_array ();
  //Return ego/egos
  for (ego_entry = handle->ego_head;
  NULL != ego_entry; ego_entry = ego_entry->next)
  {
    json_ego = json_object ();
    json_object_set_new (json_ego,
			 GNUNET_REST_IDENTITY_PARAM_PUBKEY,
			 json_string (ego_entry->keystring));
    json_object_set_new (json_ego,
			 GNUNET_REST_IDENTITY_PARAM_NAME,
			 json_string (ego_entry->identifier));
    json_array_append (json_root, json_ego);
    json_decref (json_ego);
  }

  if ((size_t) 0 == json_array_size (json_root))
  {
    json_decref (json_root);
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  result_str = json_dumps (json_root, 0);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Result %s\n", result_str);
  resp = GNUNET_REST_create_response (result_str);

  json_decref (json_root);
  handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
  GNUNET_free(result_str);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
}


/**
 * Responds with the ego_entry identity
 *
 * @param handle the struct RequestHandle
 * @param ego_entry the struct EgoEntry for the response
 */
void
ego_get_response (struct RequestHandle *handle, struct EgoEntry *ego_entry)
{
  struct MHD_Response *resp;
  json_t *json_ego;
  char *result_str;

  json_ego = json_object ();
  json_object_set_new (json_ego,
		       GNUNET_REST_IDENTITY_PARAM_PUBKEY,
		       json_string (ego_entry->keystring));
  json_object_set_new (json_ego,
		       GNUNET_REST_IDENTITY_PARAM_NAME,
		       json_string (ego_entry->identifier));

  result_str = json_dumps (json_ego, 0);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Result %s\n", result_str);
  resp = GNUNET_REST_create_response (result_str);
  handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);

  json_decref (json_ego);
  GNUNET_free(result_str);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
}


/**
 * Handle identity GET request with a public key
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_get_pubkey (struct GNUNET_REST_RequestHandle *con_handle,
		const char* url,
		void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *keystring;

  keystring = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_PUBKEY);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  keystring = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY)+1];
  ego_entry = get_egoentry(handle, keystring, NULL);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  ego_get_response(handle, ego_entry);
}

/**
 * Handle identity GET request with a name
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_get_name (struct GNUNET_REST_RequestHandle *con_handle,
	      const char* url,
	      void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *egoname;

  egoname = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_NAME) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_NAME);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  egoname = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_NAME)+1];
  ego_entry = get_egoentry(handle, NULL, egoname);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  ego_get_response(handle, ego_entry);
}


/**
 * Processing finished
 *
 * @param cls request handle
 * @param emsg error message
 */
static void
do_finished (void *cls, const char *emsg)
{
  struct RequestHandle *handle = cls;
  struct MHD_Response *resp;

  handle->op = NULL;
  if (NULL != emsg)
  {
    handle->emsg = GNUNET_strdup(emsg);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  if (0 == handle->response_code)
  {
    handle->response_code = MHD_HTTP_NO_CONTENT;
  }
  resp = GNUNET_REST_create_response (NULL);
  handle->proc (handle->proc_cls, resp, handle->response_code);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
}


/**
 * Processing edit ego with EgoEntry ego_entry
 *
 * @param handle the struct RequestHandle
 * @param ego_entry the struct EgoEntry we want to edit
 */
void
ego_edit (struct RequestHandle *handle, struct EgoEntry *ego_entry)
{
  struct EgoEntry *ego_entry_tmp;
  struct MHD_Response *resp;
  json_t *data_js;
  json_error_t err;
  char *newname;
  char term_data[handle->data_size + 1];
  int json_state;

  //if no data
  if (0 >= handle->data_size)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  //if not json
  term_data[handle->data_size] = '\0';
  GNUNET_memcpy(term_data, handle->data, handle->data_size);
  data_js = json_loads (term_data,JSON_DECODE_ANY,&err);

  if (NULL == data_js)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  newname = NULL;
  //NEW NAME
  json_state = 0;
  json_state = json_unpack(data_js,
			   "{s:s!}",
			   GNUNET_REST_IDENTITY_PARAM_NEWNAME,
			   &newname);
  //Change name with pubkey or name identifier
  if (0 != json_state)
  {

    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  if (NULL == newname)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  if (0 >= strlen (newname))
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  ego_entry_tmp = get_egoentry (handle, NULL, newname);
  if (NULL != ego_entry_tmp)
  {
    //Ego with same name not allowed (even if its the ego we change)
    resp = GNUNET_REST_create_response (NULL);
    handle->proc (handle->proc_cls, resp, MHD_HTTP_CONFLICT);
    GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
    json_decref (data_js);
    return;
  }
  handle->op = GNUNET_IDENTITY_rename (handle->identity_handle,
				       ego_entry->identifier,
				       newname,
				       &do_finished,
				       handle);
  if (NULL == handle->op)
  {
    handle->emsg = GNUNET_strdup("Rename failed");
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }
  json_decref (data_js);
  return;

}


/**
 * Handle identity PUT request with public key
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_edit_pubkey (struct GNUNET_REST_RequestHandle *con_handle,
		 const char* url,
		 void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *keystring;

  keystring = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_PUBKEY);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  keystring = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY)+1];
  ego_entry = get_egoentry(handle, keystring, NULL);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  ego_edit(handle,ego_entry);
}

/**
 * Handle identity PUT request with name
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_edit_name (struct GNUNET_REST_RequestHandle *con_handle,
	       const char* url,
	       void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *name;

  name = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_NAME) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_NAME);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  name = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_NAME)+1];
  ego_entry = get_egoentry(handle, NULL, name);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  ego_edit(handle,ego_entry);
}

/**
 * Handle identity subsystem PUT request with name
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_edit_subsystem (struct GNUNET_REST_RequestHandle *con_handle,
		    const char* url,
		    void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  json_t *data_js;
  json_error_t err;
  char *newsubsys;
  char *name;
  char term_data[handle->data_size + 1];
  int json_state;

  name = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_NAME);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  name = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM)+1];
  ego_entry = get_egoentry(handle, NULL, name);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  //if no data
  if (0 >= handle->data_size)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  //if not json
  term_data[handle->data_size] = '\0';
  GNUNET_memcpy(term_data, handle->data, handle->data_size);
  data_js = json_loads (term_data,JSON_DECODE_ANY,&err);

  if (NULL == data_js)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  newsubsys = NULL;
  //SUBSYSTEM
  json_state = 0;
  json_state = json_unpack(data_js,
			   "{s:s!}",
			   GNUNET_REST_IDENTITY_PARAM_SUBSYSTEM,
			   &newsubsys);
  //Change subsystem with pubkey or name identifier
  if (0 != json_state)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  if (NULL == newsubsys)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  if (0 >= strlen (newsubsys))
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  handle->response_code = MHD_HTTP_NO_CONTENT;
  handle->op = GNUNET_IDENTITY_set (handle->identity_handle,
				    newsubsys,
				    ego_entry->ego,
				    &do_finished,
				    handle);
  if (NULL == handle->op)
  {
    handle->emsg = GNUNET_strdup("Setting subsystem failed");
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  json_decref (data_js);
  return;

}

/**
 * Handle identity POST request
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_create (struct GNUNET_REST_RequestHandle *con_handle,
	    const char* url,
	    void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  struct MHD_Response *resp;
  json_t *data_js;
  json_error_t err;
  char* egoname;
  int json_unpack_state;
  char term_data[handle->data_size + 1];

  if (strlen (GNUNET_REST_API_NS_IDENTITY) != strlen (handle->url))
  {
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  if (0 >= handle->data_size)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  term_data[handle->data_size] = '\0';
  GNUNET_memcpy(term_data, handle->data, handle->data_size);
  data_js = json_loads (term_data,
			JSON_DECODE_ANY,
			&err);
  if (NULL == data_js)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_NO_DATA);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }
  json_unpack_state = 0;
  json_unpack_state = json_unpack(data_js,
				  "{s:s!}",
				  GNUNET_REST_IDENTITY_PARAM_NAME,
				  &egoname);
  if (0 != json_unpack_state)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }

  if (NULL == egoname)
  {
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    json_decref (data_js);
    return;
  }
  if (0 >= strlen (egoname))
  {
    json_decref (data_js);
    handle->emsg = GNUNET_strdup(GNUNET_REST_ERROR_DATA_INVALID);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  GNUNET_STRINGS_utf8_tolower(egoname, egoname);
  for (ego_entry = handle->ego_head;
  NULL != ego_entry; ego_entry = ego_entry->next)
  {
    if (0 == strcasecmp (egoname, ego_entry->identifier))
    {
      resp = GNUNET_REST_create_response (NULL);
      handle->proc (handle->proc_cls, resp, MHD_HTTP_CONFLICT);
      GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
      json_decref (data_js);
      return;
    }
  }
  handle->name = GNUNET_strdup(egoname);
  json_decref (data_js);
  handle->response_code = MHD_HTTP_CREATED;
  handle->op = GNUNET_IDENTITY_create (handle->identity_handle, handle->name,
				       &do_finished, handle);
}

/**
 * Handle identity DELETE request with public key
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_delete_pubkey (struct GNUNET_REST_RequestHandle *con_handle,
		   const char* url,
		   void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *keystring;

  keystring = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_PUBKEY);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  keystring = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_PUBKEY)+1];
  ego_entry = get_egoentry(handle, keystring, NULL);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  handle->response_code = MHD_HTTP_NO_CONTENT;
  handle->op = GNUNET_IDENTITY_delete (handle->identity_handle,
				       ego_entry->identifier,
				       &do_finished,
				       handle);
}


/**
 * Handle identity DELETE request with name
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
void
ego_delete_name (struct GNUNET_REST_RequestHandle *con_handle,
		   const char* url,
		   void *cls)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  char *name;

  name = NULL;

  if (strlen (GNUNET_REST_API_NS_IDENTITY_NAME) >= strlen (handle->url))
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_MISSING_NAME);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }
  name = &handle->url[strlen (GNUNET_REST_API_NS_IDENTITY_NAME)+1];
  ego_entry = get_egoentry(handle, NULL, name);

  if (NULL == ego_entry)
  {
    handle->response_code = MHD_HTTP_NOT_FOUND;
    handle->emsg = GNUNET_strdup(GNUNET_REST_IDENTITY_NOT_FOUND);
    GNUNET_SCHEDULER_add_now (&do_error, handle);
    return;
  }

  handle->response_code = MHD_HTTP_NO_CONTENT;
  handle->op = GNUNET_IDENTITY_delete (handle->identity_handle,
				       ego_entry->identifier,
				       &do_finished,
				       handle);
}


/**
 * Respond to OPTIONS request
 *
 * @param con_handle the connection handle
 * @param url the url
 * @param cls the RequestHandle
 */
static void
options_cont (struct GNUNET_REST_RequestHandle *con_handle, const char* url,
	      void *cls)
{
  struct MHD_Response *resp;
  struct RequestHandle *handle = cls;

  //For now, independent of path return all options
  resp = GNUNET_REST_create_response (NULL);
  MHD_add_response_header (resp, "Access-Control-Allow-Methods", allow_methods);
  handle->proc (handle->proc_cls, resp, MHD_HTTP_OK);
  GNUNET_SCHEDULER_add_now (&cleanup_handle, handle);
  return;
}

/**
 * Handle rest request
 *
 * @param handle the request handle
 */
static void
init_cont (struct RequestHandle *handle)
{
  struct GNUNET_REST_RequestHandlerError err;
  static const struct GNUNET_REST_RequestHandler handlers[] = {
      { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_IDENTITY_ALL, &ego_get_all },
      { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_IDENTITY_PUBKEY, &ego_get_pubkey },
      { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_IDENTITY_NAME, &ego_get_name },
      { MHD_HTTP_METHOD_GET, GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM, &ego_get_subsystem },
      { MHD_HTTP_METHOD_PUT, GNUNET_REST_API_NS_IDENTITY_PUBKEY, &ego_edit_pubkey },
      { MHD_HTTP_METHOD_PUT, GNUNET_REST_API_NS_IDENTITY_NAME, &ego_edit_name },
      { MHD_HTTP_METHOD_PUT, GNUNET_REST_API_NS_IDENTITY_SUBSYSTEM, &ego_edit_subsystem },
      { MHD_HTTP_METHOD_POST, GNUNET_REST_API_NS_IDENTITY, &ego_create },
      { MHD_HTTP_METHOD_DELETE, GNUNET_REST_API_NS_IDENTITY_PUBKEY, &ego_delete_pubkey },
      { MHD_HTTP_METHOD_DELETE, GNUNET_REST_API_NS_IDENTITY_NAME, &ego_delete_name },
      { MHD_HTTP_METHOD_OPTIONS, GNUNET_REST_API_NS_IDENTITY, &options_cont },
      GNUNET_REST_HANDLER_END
  };

  if (GNUNET_NO
      == GNUNET_REST_handle_request (handle->rest_handle, handlers, &err,
				     handle))
  {
    handle->response_code = err.error_code;
    GNUNET_SCHEDULER_add_now (&do_error, handle);
  }
}

/**
 * If listing is enabled, prints information about the egos.
 *
 * This function is initially called for all egos and then again
 * whenever a ego's identifier changes or if it is deleted.  At the
 * end of the initial pass over all egos, the function is once called
 * with 'NULL' for 'ego'. That does NOT mean that the callback won't
 * be invoked in the future or that there was an error.
 *
 * When used with 'GNUNET_IDENTITY_create' or 'GNUNET_IDENTITY_get',
 * this function is only called ONCE, and 'NULL' being passed in
 * 'ego' does indicate an error (i.e. name is taken or no default
 * value is known).  If 'ego' is non-NULL and if '*ctx'
 * is set in those callbacks, the value WILL be passed to a subsequent
 * call to the identity callback of 'GNUNET_IDENTITY_connect' (if
 * that one was not NULL).
 *
 * When an identity is renamed, this function is called with the
 * (known) ego but the NEW identifier.
 *
 * When an identity is deleted, this function is called with the
 * (known) ego and "NULL" for the 'identifier'.  In this case,
 * the 'ego' is henceforth invalid (and the 'ctx' should also be
 * cleaned up).
 *
 * @param cls closure
 * @param ego ego handle
 * @param ctx context for application to store data for this ego
 *                 (during the lifetime of this process, initially NULL)
 * @param identifier identifier assigned by the user for this ego,
 *                   NULL if the user just deleted the ego and it
 *                   must thus no longer be used
 */
static void
init_egos (void *cls, struct GNUNET_IDENTITY_Ego *ego, void **ctx,
	   const char *identifier)
{
  struct RequestHandle *handle = cls;
  struct EgoEntry *ego_entry;
  struct GNUNET_CRYPTO_EcdsaPublicKey pk;

  if ((NULL == ego) && (ID_REST_STATE_INIT == handle->state))
  {
    handle->state = ID_REST_STATE_POST_INIT;
    init_cont (handle);
    return;
  }
  if (ID_REST_STATE_INIT == handle->state)
  {
    ego_entry = GNUNET_new(struct EgoEntry);
    GNUNET_IDENTITY_ego_get_public_key (ego, &pk);
    ego_entry->keystring = GNUNET_CRYPTO_ecdsa_public_key_to_string (&pk);
    ego_entry->ego = ego;
    GNUNET_asprintf (&ego_entry->identifier, "%s", identifier);
    GNUNET_CONTAINER_DLL_insert_tail(handle->ego_head, handle->ego_tail,
				     ego_entry);
  }
}

/**
 * Function processing the REST call
 *
 * @param method HTTP method
 * @param url URL of the HTTP request
 * @param data body of the HTTP request (optional)
 * @param data_size length of the body
 * @param proc callback function for the result
 * @param proc_cls closure for callback function
 * @return GNUNET_OK if request accepted
 */
static void
rest_process_request (struct GNUNET_REST_RequestHandle *rest_handle,
		      GNUNET_REST_ResultProcessor proc, void *proc_cls)
{
  struct RequestHandle *handle = GNUNET_new(struct RequestHandle);

  handle->response_code = 0;
  handle->timeout = GNUNET_TIME_UNIT_FOREVER_REL;
  handle->proc_cls = proc_cls;
  handle->proc = proc;
  handle->rest_handle = rest_handle;
  handle->data = rest_handle->data;
  handle->data_size = rest_handle->data_size;

  handle->url = GNUNET_strdup(rest_handle->url);
  if (handle->url[strlen (handle->url) - 1] == '/')
    handle->url[strlen (handle->url) - 1] = '\0';
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connecting...\n");

  handle->identity_handle = GNUNET_IDENTITY_connect (cfg, &init_egos, handle);

  handle->timeout_task = GNUNET_SCHEDULER_add_delayed (handle->timeout,
						       &do_error, handle);

  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Connected\n");
}

/**
 * Entry point for the plugin.
 *
 * @param cls Config info
 * @return NULL on error, otherwise the plugin context
 */
void *
libgnunet_plugin_rest_identity_init (void *cls)
{
  static struct Plugin plugin;
  struct GNUNET_REST_Plugin *api;

  cfg = cls;
  if (NULL != plugin.cfg)
    return NULL; /* can only initialize once! */
  memset (&plugin, 0, sizeof(struct Plugin));
  plugin.cfg = cfg;
  api = GNUNET_new(struct GNUNET_REST_Plugin);
  api->cls = &plugin;
  api->name = GNUNET_REST_API_NS_IDENTITY;
  api->process_request = &rest_process_request;
  GNUNET_asprintf (&allow_methods, "%s, %s, %s, %s, %s",
		   MHD_HTTP_METHOD_GET,
		   MHD_HTTP_METHOD_POST,
		   MHD_HTTP_METHOD_PUT,
		   MHD_HTTP_METHOD_DELETE,
		   MHD_HTTP_METHOD_OPTIONS);

  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, _("Identity REST API initialized\n"));
  return api;
}

/**
 * Exit point from the plugin.
 *
 * @param cls the plugin context (as returned by "init")
 * @return always NULL
 */
void *
libgnunet_plugin_rest_identity_done (void *cls)
{
  struct GNUNET_REST_Plugin *api = cls;
  struct Plugin *plugin = api->cls;
  plugin->cfg = NULL;

  GNUNET_free_non_null(allow_methods);
  GNUNET_free(api);
  GNUNET_log(GNUNET_ERROR_TYPE_DEBUG, "Identity REST plugin is finished\n");
  return NULL;
}

/* end of plugin_rest_identity.c */