/*

 * Copyright (c) 2019 Fastly

 *

 * 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 <ctype.h>

#include "h2o.h"

#include "h2o/absprio.h"

h2o_absprio_t h2o_absprio_default = {H2O_ABSPRIO_DEFAULT_URGENCY, 0};

void h2o_absprio_parse_priority(const char *s, size_t len, h2o_absprio_t *prio)

{

    h2o_iovec_t iter = h2o_iovec_init(s, len), value;

    const char *token;

    size_t token_len;

    while ((token = h2o_next_token(&iter, ',', ',', &token_len, &value)) != NULL) {

        if (token_len != 1) {

            /* Currently only "u=" and "i=" are supported. Thus token_len should always be 1.

             * Ignore unknown keys. */

            continue;

        }

        if (token[0] == 'u') {

            H2O_BUILD_ASSERT(H2O_ABSPRIO_NUM_URGENCY_LEVELS < 10);

            if (value.base != NULL && value.len == 1 && '0' <= value.base[0] &&

                value.base[0] <= '0' + H2O_ABSPRIO_NUM_URGENCY_LEVELS - 1)

                prio->urgency = value.base[0] - '0';

        } else if (token[0] == 'i') {

            if (value.base != NULL) {

                if (value.len == 2 && value.base[0] == '?') {

                    /* value should contain '?0' or '?1' */

                    if (value.base[1] == '0')

                        prio->incremental = 0;

                    else if (value.base[1] == '1')

                        prio->incremental = 1;

                    /* All other cases mean invalid format. Just ignore. */

                }

            } else {

                /* value omitted, meaning that i is true */

                prio->incremental = 1;

            }

        }

    }

}