/*
 *
 * Copyright 2016, 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,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/* With the addition of a libuv endpoint, sockaddr.h now includes uv.h when
   using that endpoint. Because of various transitive includes in uv.h,
   including windows.h on Windows, uv.h must be included before other system
   headers. Therefore, sockaddr.h must always be included first */
#include "src/core/lib/iomgr/sockaddr.h"

#include <string.h>

#include <grpc/grpc.h>
#include <grpc/slice.h>
#include <grpc/support/alloc.h>
#include <grpc/support/host_port.h>
#include <grpc/support/log.h>
#include <grpc/support/thd.h>

#include "src/core/lib/iomgr/sockaddr.h"
#include "src/core/lib/slice/slice_internal.h"
#include "src/core/lib/slice/slice_string_helpers.h"
#include "src/core/lib/support/string.h"
#include "test/core/end2end/cq_verifier.h"
#include "test/core/util/port.h"
#include "test/core/util/test_config.h"
#include "test/core/util/test_tcp_server.h"

#define HTTP1_RESP                           \
  "HTTP/1.0 400 Bad Request\n"               \
  "Content-Type: text/html; charset=UTF-8\n" \
  "Content-Length: 0\n"                      \
  "Date: Tue, 07 Jun 2016 17:43:20 GMT\n\n"

#define HTTP2_RESP(STATUS_CODE)          \
  "\x00\x00\x00\x04\x00\x00\x00\x00\x00" \
  "\x00\x00>\x01\x04\x00\x00\x00\x01"    \
  "\x10\x0e"                             \
  "content-length\x01"                   \
  "0"                                    \
  "\x10\x0c"                             \
  "content-type\x10"                     \
  "application/grpc"                     \
  "\x10\x07:status\x03" #STATUS_CODE

#define UNPARSEABLE_RESP "Bad Request\n"

#define HTTP2_DETAIL_MSG(STATUS_CODE) \
  "Received http2 header with status: " #STATUS_CODE

#define UNPARSEABLE_DETAIL_MSG "Failed parsing HTTP/2"

#define HTTP1_DETAIL_MSG "Trying to connect an http1.x server"

/* TODO(zyc) Check the content of incomming data instead of using this length */
/* The 'bad' server will start sending responses after reading this amount of
 * data from the client. */
#define SERVER_INCOMING_DATA_LENGTH_LOWER_THRESHOLD (size_t)200

struct rpc_state {
  char *target;
  grpc_completion_queue *cq;
  grpc_channel *channel;
  grpc_call *call;
  size_t incoming_data_length;
  grpc_slice_buffer temp_incoming_buffer;
  grpc_slice_buffer outgoing_buffer;
  grpc_endpoint *tcp;
  gpr_atm done_atm;
  bool write_done;
  const char *response_payload;
  size_t response_payload_length;
};

static int server_port;
static struct rpc_state state;
static grpc_closure on_read;
static grpc_closure on_write;

static void *tag(intptr_t t) { return (void *)t; }

static void done_write(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
  GPR_ASSERT(error == GRPC_ERROR_NONE);

  gpr_atm_rel_store(&state.done_atm, 1);
}

static void handle_write(grpc_exec_ctx *exec_ctx) {
  grpc_slice slice = grpc_slice_from_copied_buffer(
      state.response_payload, state.response_payload_length);

  grpc_slice_buffer_reset_and_unref(&state.outgoing_buffer);
  grpc_slice_buffer_add(&state.outgoing_buffer, slice);
  grpc_endpoint_write(exec_ctx, state.tcp, &state.outgoing_buffer, &on_write);
}

static void handle_read(grpc_exec_ctx *exec_ctx, void *arg, grpc_error *error) {
  GPR_ASSERT(error == GRPC_ERROR_NONE);
  state.incoming_data_length += state.temp_incoming_buffer.length;

  size_t i;
  for (i = 0; i < state.temp_incoming_buffer.count; i++) {
    char *dump = grpc_dump_slice(state.temp_incoming_buffer.slices[i],
                                 GPR_DUMP_HEX | GPR_DUMP_ASCII);
    gpr_log(GPR_DEBUG, "Server received: %s", dump);
    gpr_free(dump);
  }

  gpr_log(GPR_DEBUG, "got %" PRIuPTR " bytes, expected %" PRIuPTR " bytes",
          state.incoming_data_length,
          SERVER_INCOMING_DATA_LENGTH_LOWER_THRESHOLD);
  if (state.incoming_data_length >=
      SERVER_INCOMING_DATA_LENGTH_LOWER_THRESHOLD) {
    handle_write(exec_ctx);
  } else {
    grpc_endpoint_read(exec_ctx, state.tcp, &state.temp_incoming_buffer,
                       &on_read);
  }
}

static void on_connect(grpc_exec_ctx *exec_ctx, void *arg, grpc_endpoint *tcp,
                       grpc_pollset *accepting_pollset,
                       grpc_tcp_server_acceptor *acceptor) {
  gpr_free(acceptor);
  test_tcp_server *server = arg;
  grpc_closure_init(&on_read, handle_read, NULL, grpc_schedule_on_exec_ctx);
  grpc_closure_init(&on_write, done_write, NULL, grpc_schedule_on_exec_ctx);
  grpc_slice_buffer_init(&state.temp_incoming_buffer);
  grpc_slice_buffer_init(&state.outgoing_buffer);
  state.tcp = tcp;
  state.incoming_data_length = 0;
  grpc_endpoint_add_to_pollset(exec_ctx, tcp, server->pollset);
  grpc_endpoint_read(exec_ctx, tcp, &state.temp_incoming_buffer, &on_read);
}

static gpr_timespec n_sec_deadline(int seconds) {
  return gpr_time_add(gpr_now(GPR_CLOCK_REALTIME),
                      gpr_time_from_seconds(seconds, GPR_TIMESPAN));
}

static void start_rpc(int target_port, grpc_status_code expected_status,
                      const char *expected_detail) {
  grpc_op ops[6];
  grpc_op *op;
  grpc_metadata_array initial_metadata_recv;
  grpc_metadata_array trailing_metadata_recv;
  grpc_status_code status;
  grpc_call_error error;
  cq_verifier *cqv;
  grpc_slice details;

  state.cq = grpc_completion_queue_create_for_next(NULL);
  cqv = cq_verifier_create(state.cq);
  gpr_join_host_port(&state.target, "127.0.0.1", target_port);
  state.channel = grpc_insecure_channel_create(state.target, NULL, NULL);
  grpc_slice host = grpc_slice_from_static_string("localhost");
  state.call = grpc_channel_create_call(
      state.channel, NULL, GRPC_PROPAGATE_DEFAULTS, state.cq,
      grpc_slice_from_static_string("/Service/Method"), &host,
      gpr_inf_future(GPR_CLOCK_REALTIME), NULL);

  grpc_metadata_array_init(&initial_metadata_recv);
  grpc_metadata_array_init(&trailing_metadata_recv);

  memset(ops, 0, sizeof(ops));
  op = ops;
  op->op = GRPC_OP_SEND_INITIAL_METADATA;
  op->data.send_initial_metadata.count = 0;
  op->flags = 0;
  op->reserved = NULL;
  op++;
  op->op = GRPC_OP_SEND_CLOSE_FROM_CLIENT;
  op->flags = 0;
  op->reserved = NULL;
  op++;
  op->op = GRPC_OP_RECV_INITIAL_METADATA;
  op->data.recv_initial_metadata.recv_initial_metadata = &initial_metadata_recv;
  op->flags = 0;
  op->reserved = NULL;
  op++;
  op->op = GRPC_OP_RECV_STATUS_ON_CLIENT;
  op->data.recv_status_on_client.trailing_metadata = &trailing_metadata_recv;
  op->data.recv_status_on_client.status = &status;
  op->data.recv_status_on_client.status_details = &details;
  op->flags = 0;
  op->reserved = NULL;
  op++;
  error =
      grpc_call_start_batch(state.call, ops, (size_t)(op - ops), tag(1), NULL);

  GPR_ASSERT(GRPC_CALL_OK == error);

  CQ_EXPECT_COMPLETION(cqv, tag(1), 1);
  cq_verify(cqv);

  GPR_ASSERT(status == expected_status);
  GPR_ASSERT(-1 != grpc_slice_slice(details, grpc_slice_from_static_string(
                                                 expected_detail)));

  grpc_metadata_array_destroy(&initial_metadata_recv);
  grpc_metadata_array_destroy(&trailing_metadata_recv);
  grpc_slice_unref(details);
  cq_verifier_destroy(cqv);
}

static void cleanup_rpc(grpc_exec_ctx *exec_ctx) {
  grpc_event ev;
  grpc_slice_buffer_destroy_internal(exec_ctx, &state.temp_incoming_buffer);
  grpc_slice_buffer_destroy_internal(exec_ctx, &state.outgoing_buffer);
  grpc_call_unref(state.call);
  grpc_completion_queue_shutdown(state.cq);
  do {
    ev = grpc_completion_queue_next(state.cq, n_sec_deadline(1), NULL);
  } while (ev.type != GRPC_QUEUE_SHUTDOWN);
  grpc_completion_queue_destroy(state.cq);
  grpc_channel_destroy(state.channel);
  gpr_free(state.target);
}

typedef struct {
  test_tcp_server *server;
  gpr_event *signal_when_done;
} poll_args;

static void actually_poll_server(void *arg) {
  poll_args *pa = arg;
  gpr_timespec deadline = n_sec_deadline(10);
  while (true) {
    bool done = gpr_atm_acq_load(&state.done_atm) != 0;
    gpr_timespec time_left =
        gpr_time_sub(deadline, gpr_now(GPR_CLOCK_REALTIME));
    gpr_log(GPR_DEBUG, "done=%d, time_left=%" PRId64 ".%09d", done,
            time_left.tv_sec, time_left.tv_nsec);
    if (done || gpr_time_cmp(time_left, gpr_time_0(GPR_TIMESPAN)) < 0) {
      break;
    }
    test_tcp_server_poll(pa->server, 1);
  }
  gpr_event_set(pa->signal_when_done, (void *)1);
  gpr_free(pa);
}

static void poll_server_until_read_done(test_tcp_server *server,
                                        gpr_event *signal_when_done) {
  gpr_atm_rel_store(&state.done_atm, 0);
  state.write_done = 0;
  gpr_thd_id id;
  poll_args *pa = gpr_malloc(sizeof(*pa));
  pa->server = server;
  pa->signal_when_done = signal_when_done;
  gpr_thd_new(&id, actually_poll_server, pa, NULL);
}

static void run_test(const char *response_payload,
                     size_t response_payload_length,
                     grpc_status_code expected_status,
                     const char *expected_detail) {
  test_tcp_server test_server;
  grpc_exec_ctx exec_ctx = GRPC_EXEC_CTX_INIT;
  gpr_event ev;

  grpc_init();
  gpr_event_init(&ev);
  server_port = grpc_pick_unused_port_or_die();
  test_tcp_server_init(&test_server, on_connect, &test_server);
  test_tcp_server_start(&test_server, server_port);
  state.response_payload = response_payload;
  state.response_payload_length = response_payload_length;

  /* poll server until sending out the response */
  poll_server_until_read_done(&test_server, &ev);
  start_rpc(server_port, expected_status, expected_detail);
  gpr_event_wait(&ev, gpr_inf_future(GPR_CLOCK_REALTIME));

  /* clean up */
  grpc_endpoint_shutdown(&exec_ctx, state.tcp,
                         GRPC_ERROR_CREATE_FROM_STATIC_STRING("Test Shutdown"));
  grpc_endpoint_destroy(&exec_ctx, state.tcp);
  cleanup_rpc(&exec_ctx);
  grpc_exec_ctx_finish(&exec_ctx);
  test_tcp_server_destroy(&test_server);

  grpc_shutdown();
}

int main(int argc, char **argv) {
  grpc_test_init(argc, argv);

  /* status defined in hpack static table */
  run_test(HTTP2_RESP(204), sizeof(HTTP2_RESP(204)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(204));

  run_test(HTTP2_RESP(206), sizeof(HTTP2_RESP(206)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(206));

  run_test(HTTP2_RESP(304), sizeof(HTTP2_RESP(304)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(304));

  run_test(HTTP2_RESP(400), sizeof(HTTP2_RESP(400)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(400));

  run_test(HTTP2_RESP(404), sizeof(HTTP2_RESP(404)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(404));

  run_test(HTTP2_RESP(500), sizeof(HTTP2_RESP(500)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(500));

  /* status not defined in hpack static table */
  run_test(HTTP2_RESP(401), sizeof(HTTP2_RESP(401)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(401));

  run_test(HTTP2_RESP(403), sizeof(HTTP2_RESP(403)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(403));

  run_test(HTTP2_RESP(502), sizeof(HTTP2_RESP(502)) - 1, GRPC_STATUS_CANCELLED,
           HTTP2_DETAIL_MSG(502));

  /* unparseable response */
  run_test(UNPARSEABLE_RESP, sizeof(UNPARSEABLE_RESP) - 1,
           GRPC_STATUS_UNAVAILABLE, UNPARSEABLE_DETAIL_MSG);

  /* http1 response */
  run_test(HTTP1_RESP, sizeof(HTTP1_RESP) - 1, GRPC_STATUS_UNAVAILABLE,
           HTTP1_DETAIL_MSG);

  return 0;
}