/*
 *
 * Copyright 2015, Google Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *     * Neither the name of Google Inc. nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */

#include "test/core/security/oauth2_utils.h"

#include <string.h>

#include <grpc/grpc.h>
#include <grpc/grpc_security.h>
#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/slice.h>
#include <grpc/support/sync.h>

#include "src/core/security/credentials.h"

typedef struct
{
  grpc_pollset pollset;
  int is_done;
  char *token;
} oauth2_request;

static void
on_oauth2_response (grpc_exec_ctx * exec_ctx, void *user_data, grpc_credentials_md * md_elems, size_t num_md, grpc_credentials_status status)
{
  oauth2_request *request = user_data;
  char *token = NULL;
  gpr_slice token_slice;
  if (status == GRPC_CREDENTIALS_ERROR)
    {
      gpr_log (GPR_ERROR, "Fetching token failed.");
    }
  else
    {
      GPR_ASSERT (num_md == 1);
      token_slice = md_elems[0].value;
      token = gpr_malloc (GPR_SLICE_LENGTH (token_slice) + 1);
      memcpy (token, GPR_SLICE_START_PTR (token_slice), GPR_SLICE_LENGTH (token_slice));
      token[GPR_SLICE_LENGTH (token_slice)] = '\0';
    }
  gpr_mu_lock (GRPC_POLLSET_MU (&request->pollset));
  request->is_done = 1;
  request->token = token;
  grpc_pollset_kick (&request->pollset, NULL);
  gpr_mu_unlock (GRPC_POLLSET_MU (&request->pollset));
}

static void
do_nothing (grpc_exec_ctx * exec_ctx, void *unused, int success)
{
}

char *
grpc_test_fetch_oauth2_token_with_credentials (grpc_credentials * creds)
{
  oauth2_request request;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  grpc_closure do_nothing_closure;
  grpc_pollset_init (&request.pollset);
  request.is_done = 0;

  grpc_closure_init (&do_nothing_closure, do_nothing, NULL);

  grpc_credentials_get_request_metadata (&exec_ctx, creds, &request.pollset, "", on_oauth2_response, &request);

  grpc_exec_ctx_finish (&exec_ctx);

  gpr_mu_lock (GRPC_POLLSET_MU (&request.pollset));
  while (!request.is_done)
    {
      grpc_pollset_worker worker;
      grpc_pollset_work (&exec_ctx, &request.pollset, &worker, gpr_now (GPR_CLOCK_MONOTONIC), gpr_inf_future (GPR_CLOCK_MONOTONIC));
    }
  gpr_mu_unlock (GRPC_POLLSET_MU (&request.pollset));

  grpc_pollset_shutdown (&exec_ctx, &request.pollset, &do_nothing_closure);
  grpc_exec_ctx_finish (&exec_ctx);
  grpc_pollset_destroy (&request.pollset);
  return request.token;
}