/*
 * nghttp3
 *
 * Copyright (c) 2019 nghttp3 contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject to
 * the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include "nghttp3_test_helper.h"

#include <string.h>
#include <assert.h>

#include "nghttp3_str.h"
#include "nghttp3_conv.h"

void nghttp3_write_frame(nghttp3_buf *dest, const nghttp3_frame *fr) {
  int64_t payloadlen;

  switch (fr->hd.type) {
  case NGHTTP3_FRAME_SETTINGS:
    nghttp3_frame_write_settings_len(&payloadlen, &fr->settings);
    dest->last =
      nghttp3_frame_write_settings(dest->last, &fr->settings, payloadlen);
    break;
  case NGHTTP3_FRAME_GOAWAY:
    nghttp3_frame_write_goaway_len(&payloadlen, &fr->goaway);
    dest->last =
      nghttp3_frame_write_goaway(dest->last, &fr->goaway, payloadlen);
    break;
  case NGHTTP3_FRAME_PRIORITY_UPDATE:
  case NGHTTP3_FRAME_PRIORITY_UPDATE_PUSH_ID:
    nghttp3_frame_write_priority_update_len(&payloadlen, &fr->priority_update);
    dest->last = nghttp3_frame_write_priority_update(
      dest->last, &fr->priority_update, payloadlen);
    break;
  case NGHTTP3_FRAME_ORIGIN:
    nghttp3_frame_write_origin_len(&payloadlen, &fr->origin);
    dest->last =
      nghttp3_frame_write_origin(dest->last, &fr->origin, payloadlen);
    break;
  default:
    assert(0);
  }
}

void nghttp3_write_frame_qpack(nghttp3_buf *dest, nghttp3_qpack_encoder *qenc,
                               int64_t stream_id, const nghttp3_frame *fr) {
  int rv;
  const nghttp3_nv *nva;
  size_t nvlen;
  nghttp3_buf pbuf, rbuf, ebuf;
  const nghttp3_mem *mem = nghttp3_mem_default();
  int64_t payloadlen;
  (void)rv;

  switch (fr->hd.type) {
  case NGHTTP3_FRAME_HEADERS:
    nva = fr->headers.nva;
    nvlen = fr->headers.nvlen;
    break;
  default:
    assert(0);
    abort();
  }

  nghttp3_buf_init(&pbuf);
  nghttp3_buf_init(&rbuf);
  nghttp3_buf_init(&ebuf);

  rv = nghttp3_qpack_encoder_encode(qenc, &pbuf, &rbuf, &ebuf, stream_id, nva,
                                    nvlen);
  assert(0 == rv);
  assert(0 == nghttp3_buf_len(&ebuf));

  payloadlen = (int64_t)(nghttp3_buf_len(&pbuf) + nghttp3_buf_len(&rbuf));

  dest->last = nghttp3_frame_write_hd(dest->last, fr->headers.type, payloadlen);
  dest->last = nghttp3_cpymem(dest->last, pbuf.pos, nghttp3_buf_len(&pbuf));
  dest->last = nghttp3_cpymem(dest->last, rbuf.pos, nghttp3_buf_len(&rbuf));

  nghttp3_buf_free(&rbuf, mem);
  nghttp3_buf_free(&pbuf, mem);
}

void nghttp3_write_frame_qpack_dyn(nghttp3_buf *dest, nghttp3_buf *ebuf,
                                   nghttp3_qpack_encoder *qenc,
                                   int64_t stream_id, const nghttp3_frame *fr) {
  int rv;
  const nghttp3_nv *nva;
  size_t nvlen;
  nghttp3_buf pbuf, rbuf;
  const nghttp3_mem *mem = nghttp3_mem_default();
  int64_t payloadlen;
  (void)rv;

  switch (fr->hd.type) {
  case NGHTTP3_FRAME_HEADERS:
    nva = fr->headers.nva;
    nvlen = fr->headers.nvlen;
    break;
  default:
    assert(0);
    abort();
  }

  nghttp3_buf_init(&pbuf);
  nghttp3_buf_init(&rbuf);

  rv = nghttp3_qpack_encoder_encode(qenc, &pbuf, &rbuf, ebuf, stream_id, nva,
                                    nvlen);
  assert(0 == rv);

  payloadlen = (int64_t)(nghttp3_buf_len(&pbuf) + nghttp3_buf_len(&rbuf));

  dest->last = nghttp3_frame_write_hd(dest->last, fr->headers.type, payloadlen);
  dest->last = nghttp3_cpymem(dest->last, pbuf.pos, nghttp3_buf_len(&pbuf));
  dest->last = nghttp3_cpymem(dest->last, rbuf.pos, nghttp3_buf_len(&rbuf));

  nghttp3_buf_free(&rbuf, mem);
  nghttp3_buf_free(&pbuf, mem);
}

void nghttp3_write_frame_data(nghttp3_buf *dest, size_t len) {
  dest->last =
    nghttp3_frame_write_hd(dest->last, NGHTTP3_FRAME_DATA, (int64_t)len);
  memset(dest->last, 0, len);
  dest->last += len;
}

nghttp3_ssize nghttp3_decode_raw_frame_hd(nghttp3_raw_frame_hd *hd,
                                          const nghttp3_vec *vec,
                                          size_t veccnt) {
  const uint8_t *p = vec->base;
  size_t len = 2;
  size_t vlen;

  if (veccnt == 0 || vec->len < len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  vlen = nghttp3_get_varintlen(p);
  len += vlen - 1;
  if (len > vec->len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  p = nghttp3_get_varint(&hd->type, p);

  vlen = nghttp3_get_varintlen(p);
  len += vlen - 1;
  if (len > vec->len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  p = nghttp3_get_varint(&hd->length, p);

  return p - vec->base;
}

nghttp3_ssize
nghttp3_decode_priority_update_frame(nghttp3_frame_priority_update *fr,
                                     const nghttp3_vec *vec, size_t veccnt) {
  const uint8_t *p = vec->base;
  size_t vlen;
  nghttp3_ssize hdlen;
  nghttp3_raw_frame_hd hd;
  int64_t pri_elem_id;

  hdlen = nghttp3_decode_raw_frame_hd(&hd, vec, veccnt);
  if (hdlen < 0) {
    return hdlen;
  }

  if (hd.type != NGHTTP3_FRAME_PRIORITY_UPDATE) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  if (hd.length == 0 || (int64_t)hdlen + hd.length > (int64_t)vec->len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  p += hdlen;

  vlen = nghttp3_get_varintlen(p);
  if ((int64_t)vlen > hd.length) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  p = nghttp3_get_varint(&pri_elem_id, p);

  *fr = (nghttp3_frame_priority_update){
    .type = hd.type,
    .pri_elem_id = pri_elem_id,
    .data = (uint8_t *)p,
    .datalen = (size_t)hd.length - vlen,
  };

  return hdlen + (nghttp3_ssize)hd.length;
}

nghttp3_ssize nghttp3_decode_settings_frame(nghttp3_frame_settings *fr,
                                            const nghttp3_vec *vec,
                                            size_t veccnt) {
  const uint8_t *p = vec->base;
  uint64_t len;
  size_t vlen;
  size_t i;
  nghttp3_ssize hdlen;
  nghttp3_raw_frame_hd hd;

  hdlen = nghttp3_decode_raw_frame_hd(&hd, vec, veccnt);
  if (hdlen < 0) {
    return hdlen;
  }

  if (hd.type != NGHTTP3_FRAME_SETTINGS) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  if (hd.length == 0) {
    *fr = (nghttp3_frame_settings){
      .type = hd.type,
    };
    return hdlen;
  }

  if ((int64_t)hdlen + hd.length > (int64_t)vec->len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  p += hdlen;

  len = 0;

  for (i = 0; len < (uint64_t)hd.length; ++i) {
    if (i > 16) {
      return NGHTTP3_ERR_INVALID_ARGUMENT;
    }

    len += 2;
    if (len > (uint64_t)hd.length) {
      return NGHTTP3_ERR_INVALID_ARGUMENT;
    }

    vlen = nghttp3_get_varintlen(p);
    len += vlen - 1;

    if (len > (uint64_t)hd.length) {
      return NGHTTP3_ERR_INVALID_ARGUMENT;
    }

    p += vlen;
    vlen = nghttp3_get_varintlen(p);
    len += vlen - 1;

    if (len > (uint64_t)hd.length) {
      return NGHTTP3_ERR_INVALID_ARGUMENT;
    }

    p += vlen;
  }

  p = vec->base + hdlen;

  fr->type = hd.type;
  fr->niv = i;

  for (i = 0; i < fr->niv; ++i) {
    p = nghttp3_get_varint((int64_t *)&fr->iv[i].id, p);
    p = nghttp3_get_varint((int64_t *)&fr->iv[i].value, p);
  }

  return hdlen + (nghttp3_ssize)hd.length;
}

nghttp3_ssize nghttp3_decode_origin_frame(nghttp3_frame_origin *fr,
                                          const nghttp3_vec *vec,
                                          size_t veccnt) {
  nghttp3_ssize hdlen;
  nghttp3_raw_frame_hd hd;

  hdlen = nghttp3_decode_raw_frame_hd(&hd, vec, veccnt);
  if (hdlen < 0) {
    return hdlen;
  }

  if (hd.type != NGHTTP3_FRAME_ORIGIN || vec->len != (size_t)hdlen) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  if (hd.length == 0) {
    *fr = (nghttp3_frame_origin){
      .type = hd.type,
    };

    return hdlen;
  }

  if (veccnt < 2) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  ++vec;

  if (hd.length > (int64_t)vec->len) {
    return NGHTTP3_ERR_INVALID_ARGUMENT;
  }

  *fr = (nghttp3_frame_origin){
    .type = hd.type,
    .origin_list =
      {
        .base = vec->base,
        .len = (size_t)hd.length,
      },
  };

  return hdlen + (nghttp3_ssize)hd.length;
}