/*
 *
 * Copyright 2015 gRPC authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */

#include <string.h>

#include <grpc/support/alloc.h>
#include <grpc/support/log.h>
#include <grpc/support/string_util.h>

#include "src/core/ext/filters/client_channel/resolver_registry.h"
#include "src/core/lib/channel/channel_args.h"
#include "src/core/lib/iomgr/combiner.h"

#include "test/core/util/test_config.h"

static grpc_combiner* g_combiner;

typedef struct on_resolution_arg {
  char* expected_server_name;
  grpc_channel_args* resolver_result;
} on_resolution_arg;

void on_resolution_cb(void* arg, grpc_error* error) {
  on_resolution_arg* res = static_cast<on_resolution_arg*>(arg);
  grpc_channel_args_destroy(res->resolver_result);
}

static void test_succeeds(grpc_core::ResolverFactory* factory,
                          const char* string) {
  gpr_log(GPR_DEBUG, "test: '%s' should be valid for '%s'", string,
          factory->scheme());
  grpc_core::ExecCtx exec_ctx;
  grpc_uri* uri = grpc_uri_parse(string, 0);
  GPR_ASSERT(uri);
  grpc_core::ResolverArgs args;
  args.uri = uri;
  args.combiner = g_combiner;
  grpc_core::OrphanablePtr<grpc_core::Resolver> resolver =
      factory->CreateResolver(args);
  GPR_ASSERT(resolver != nullptr);

  on_resolution_arg on_res_arg;
  memset(&on_res_arg, 0, sizeof(on_res_arg));
  on_res_arg.expected_server_name = uri->path;
  grpc_closure* on_resolution = GRPC_CLOSURE_CREATE(
      on_resolution_cb, &on_res_arg, grpc_schedule_on_exec_ctx);

  resolver->NextLocked(&on_res_arg.resolver_result, on_resolution);
  grpc_uri_destroy(uri);
  /* Flush ExecCtx to avoid stack-use-after-scope on on_res_arg which is
   * accessed in the closure on_resolution_cb */
  grpc_core::ExecCtx::Get()->Flush();
}

static void test_fails(grpc_core::ResolverFactory* factory,
                       const char* string) {
  gpr_log(GPR_DEBUG, "test: '%s' should be invalid for '%s'", string,
          factory->scheme());
  grpc_core::ExecCtx exec_ctx;
  grpc_uri* uri = grpc_uri_parse(string, 0);
  GPR_ASSERT(uri);
  grpc_core::ResolverArgs args;
  args.uri = uri;
  args.combiner = g_combiner;
  grpc_core::OrphanablePtr<grpc_core::Resolver> resolver =
      factory->CreateResolver(args);
  GPR_ASSERT(resolver == nullptr);
  grpc_uri_destroy(uri);
}

int main(int argc, char** argv) {
  grpc::testing::TestEnvironment env(argc, argv);
  grpc_init();

  g_combiner = grpc_combiner_create();

  grpc_core::ResolverFactory* ipv4 =
      grpc_core::ResolverRegistry::LookupResolverFactory("ipv4");
  grpc_core::ResolverFactory* ipv6 =
      grpc_core::ResolverRegistry::LookupResolverFactory("ipv6");

  test_fails(ipv4, "ipv4:10.2.1.1");
  test_succeeds(ipv4, "ipv4:10.2.1.1:1234");
  test_succeeds(ipv4, "ipv4:10.2.1.1:1234,127.0.0.1:4321");
  test_fails(ipv4, "ipv4:10.2.1.1:123456");
  test_fails(ipv4, "ipv4:www.google.com");
  test_fails(ipv4, "ipv4:[");
  test_fails(ipv4, "ipv4://8.8.8.8/8.8.8.8:8888");

  test_fails(ipv6, "ipv6:[");
  test_fails(ipv6, "ipv6:[::]");
  test_succeeds(ipv6, "ipv6:[::]:1234");
  test_fails(ipv6, "ipv6:[::]:123456");
  test_fails(ipv6, "ipv6:www.google.com");

  {
    grpc_core::ExecCtx exec_ctx;
    GRPC_COMBINER_UNREF(g_combiner, "test");
  }
  grpc_shutdown();

  return 0;
}