/*
  This file is part of TALER
  Copyright (C) 2018 Taler Systems SA

  TALER 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, 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 exchange-lib/testing_api_cmd_withdraw.c
 * @brief main interpreter loop for testcases
 * @author Christian Grothoff
 * @author Marcello Stanisci
 */
#include "platform.h"
#include "taler_json_lib.h"
#include <gnunet/gnunet_curl_lib.h>
#include "exchange_api_handle.h"
#include "taler_signatures.h"
#include "taler_testing_lib.h"


struct WithdrawState
{

  /**
   * Which reserve should we withdraw from?
   */
  const char *reserve_reference;

  /**
   * String describing the denomination value we should withdraw.
   * A corresponding denomination key must exist in the exchange's
   * offerings.  Can be NULL if @e pk is set instead.
   */
  struct TALER_Amount amount;

  /**
   * If @e amount is NULL, this specifies the denomination key to
   * use.  Otherwise, this will be set (by the interpreter) to the
   * denomination PK matching @e amount.
   */
  const struct TALER_EXCHANGE_DenomPublicKey *pk;

  /**
   * Exchange we should use for the withdrawal.
   */
  struct TALER_EXCHANGE_Handle *exchange;

  /**
   * Exchange base URL.
   */
  char *exchange_url;

  /**
   * Interpreter state (during command).
   */
  struct TALER_TESTING_Interpreter *is;

  /**
   * Set (by the interpreter) to the exchange's signature over the
   * coin's public key.
   */
  struct TALER_DenominationSignature sig;

  /**
   * Private key material of the coin, set by the interpreter.
   */
  struct TALER_PlanchetSecretsP ps;

  /**
   * Withdraw handle (while operation is running).
   */
  struct TALER_EXCHANGE_ReserveWithdrawHandle *wsh;

  /**
   * Expected HTTP response code to the request.
   */
  unsigned int expected_response_code;

};


/**
 * Function called upon completion of our /reserve/withdraw
 * request.
 *
 * @param cls closure with the withdraw state
 * @param http_status HTTP response code, #MHD_HTTP_OK (200) for
 *        successful status request; 0 if the exchange's reply is
 *        bogus (fails to follow the protocol)
 * @param ec taler-specific error code, #TALER_EC_NONE on success
 * @param sig signature over the coin, NULL on error
 * @param full_response full response from the exchange (for
 *        logging, in case of errors)
 */
static void
reserve_withdraw_cb (void *cls,
                     unsigned int http_status,
		     enum TALER_ErrorCode ec,
                     const struct TALER_DenominationSignature *sig,
                     const json_t *full_response)
{
  struct WithdrawState *ws = cls;
  struct TALER_TESTING_Interpreter *is = ws->is;

  ws->wsh = NULL;
  if (ws->expected_response_code != http_status)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Unexpected response code %u to command %s\n",
                http_status,
                TALER_TESTING_interpreter_get_current_label (is));
    json_dumpf (full_response,
                stderr,
                0);
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (is);
    return;
  }
  switch (http_status)
  {
  case MHD_HTTP_OK:
    if (NULL == sig)
    {
      GNUNET_break (0);
      TALER_TESTING_interpreter_fail (is);
      return;
    }
    ws->sig.rsa_signature
      = GNUNET_CRYPTO_rsa_signature_dup (sig->rsa_signature);
    break;
  case MHD_HTTP_FORBIDDEN:
    /* nothing to check */
    break;
  case MHD_HTTP_NOT_FOUND:
    /* nothing to check */
    break;
  default:
    /* Unsupported status code (by test harness) */
    GNUNET_break (0);
    break;
  }
  TALER_TESTING_interpreter_next (is);
}


/**
 * Runs the command.  Note that upon return, the interpreter
 * will not automatically run the next command, as the command
 * may continue asynchronously in other scheduler tasks.  Thus,
 * the command must ensure to eventually call
 * #TALER_TESTING_interpreter_next() or
 * #TALER_TESTING_interpreter_fail().
 *
 * @param is interpreter state
 */
static void
withdraw_run (void *cls,
              const struct TALER_TESTING_Command *cmd,
              struct TALER_TESTING_Interpreter *is)
{
  struct WithdrawState *ws = cls;
  struct TALER_ReservePrivateKeyP *rp;
  const struct TALER_TESTING_Command *create_reserve;

  create_reserve = TALER_TESTING_interpreter_lookup_command
    (is, ws->reserve_reference);
  if (NULL == create_reserve)
  {
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (is);
    return;
  }
  if (GNUNET_OK !=
      TALER_TESTING_get_trait_reserve_priv (create_reserve,
                                            0,
                                            &rp))
  {
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (is);
    return;
  }
  TALER_planchet_setup_random (&ws->ps);
  ws->is = is;
  ws->wsh
    = TALER_EXCHANGE_reserve_withdraw (ws->exchange,
                                       ws->pk,
                                       rp,
                                       &ws->ps,
                                       &reserve_withdraw_cb,
                                       ws);
  if (NULL == ws->wsh)
  {
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (is);
    return;
  }
}


/**
 * Clean up after the command.  Run during forced termination
 * (CTRL-C) or test failure or test success.
 *
 * @param cls closure
 */
static void
withdraw_cleanup (void *cls,
                  const struct TALER_TESTING_Command *cmd)
{
  struct WithdrawState *ws = cls;

  if (NULL != ws->wsh)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                "Command %s did not complete\n",
                cmd->label);
    TALER_EXCHANGE_reserve_withdraw_cancel (ws->wsh);
    ws->wsh = NULL;
  }
  if (NULL != ws->sig.rsa_signature)
  {
    GNUNET_CRYPTO_rsa_signature_free (ws->sig.rsa_signature);
    ws->sig.rsa_signature = NULL;
  }
  GNUNET_free_non_null (ws->exchange_url);
  GNUNET_free (ws);
}


/**
 * Extract information from a command that is useful for other
 * commands.
 *
 * @param cls closure
 * @param ret[out] result (could be anything)
 * @param trait name of the trait
 * @param selector more detailed information about which object
 *                 to return in case there were multiple generated
 *                 by the command
 * @return #GNUNET_OK on success
 */
static int
withdraw_traits (void *cls,
                 void **ret,
                 const char *trait,
                 unsigned int index)
{
  struct WithdrawState *ws = cls;
  const struct TALER_TESTING_Command *reserve_cmd;
  struct TALER_ReservePrivateKeyP *reserve_priv;

  /* We offer the reserve key where these coins were withdrawn
   * from. */
  reserve_cmd = TALER_TESTING_interpreter_lookup_command
    (ws->is, ws->reserve_reference);

  if (NULL == reserve_cmd)
  {
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (ws->is);
    return GNUNET_SYSERR;  
  }

  if (GNUNET_OK != TALER_TESTING_get_trait_reserve_priv
    (reserve_cmd, 0, &reserve_priv))
  {
    GNUNET_break (0);
    TALER_TESTING_interpreter_fail (ws->is);
    return GNUNET_SYSERR;  
  }

  struct TALER_TESTING_Trait traits[] = {
    TALER_TESTING_make_trait_coin_priv (0 /* only one coin */,
                                        &ws->ps.coin_priv),
    TALER_TESTING_make_trait_blinding_key (0 /* only one coin */,
                                           &ws->ps.blinding_key),
    TALER_TESTING_make_trait_denom_pub (0 /* only one coin */,
                                        ws->pk),
    TALER_TESTING_make_trait_denom_sig (0 /* only one coin */,
                                        &ws->sig),
    TALER_TESTING_make_trait_reserve_priv (0,
                                           reserve_priv),
    TALER_TESTING_make_trait_amount_obj (0,
                                         &ws->amount),
    TALER_TESTING_make_trait_url (0, ws->exchange_url),

    TALER_TESTING_trait_end ()
  };

  return TALER_TESTING_get_trait (traits,
                                  ret,
                                  trait,
                                  index);
}


/**
 * Create a withdraw command.
 *
 * @param label command label, used by other commands to
 *        reference this.
 * @param exchange handle to the exchange.
 * @param amount how much we withdraw.
 * @param expected_response_code which HTTP response code
 *        we expect from the exchange.
 *
 * @return the withdraw command to be executed by the interpreter.
 */
struct TALER_TESTING_Command
TALER_TESTING_cmd_withdraw_amount
  (const char *label,
   struct TALER_EXCHANGE_Handle *exchange,
   const char *reserve_reference,
   const char *amount,
   unsigned int expected_response_code)
{
  struct TALER_TESTING_Command cmd;
  struct WithdrawState *ws;

  ws = GNUNET_new (struct WithdrawState);
  ws->reserve_reference = reserve_reference;

  if (GNUNET_OK !=
      TALER_string_to_amount (amount,
                              &ws->amount))
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Failed to parse amount `%s' at %s\n",
                amount,
                label);
    GNUNET_assert (0);
  }
  ws->pk = TALER_TESTING_find_pk
    (TALER_EXCHANGE_get_keys (exchange),
     &ws->amount);
  if (NULL == ws->pk)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Failed to determine denomination key at %s\n",
                label);
    GNUNET_assert (0);
  }
  ws->expected_response_code = expected_response_code;
  ws->exchange = exchange;
  cmd.cls = ws;
  cmd.label = label;
  cmd.run = &withdraw_run;
  cmd.cleanup = &withdraw_cleanup;
  cmd.traits = &withdraw_traits;
  return cmd;
}


/**
 * Create withdraw command.
 *
 */
struct TALER_TESTING_Command
TALER_TESTING_cmd_withdraw_denomination
  (const char *label,
   struct TALER_EXCHANGE_Handle *exchange,
   const char *reserve_reference,
   const struct TALER_EXCHANGE_DenomPublicKey *dk,
   unsigned int expected_response_code)
{
  struct TALER_TESTING_Command cmd;
  struct WithdrawState *ws;

  if (NULL == dk)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Denomination key not specified at %s\n",
                label);
    GNUNET_assert (0);
  }
  ws = GNUNET_new (struct WithdrawState);
  ws->reserve_reference = reserve_reference;
  ws->pk = dk;
  ws->expected_response_code = expected_response_code;
  ws->exchange = exchange;
  ws->exchange_url = MAH_path_to_url (ws->exchange, "/");

  cmd.cls = ws;
  cmd.label = label;
  cmd.run = &withdraw_run;
  cmd.cleanup = &withdraw_cleanup;
  cmd.traits = &withdraw_traits;
  return cmd;
}


/* end of testing_api_cmd_withdraw.c */