/*

 * Authored by Alex Hultman, 2018-2020.

 * Intellectual property of third-party.

 * 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.

 */

/* Implements the common parser (RFC 822) used in both HTTP and Multipart parsing */

#ifndef UWS_MESSAGE_PARSER_H

#define UWS_MESSAGE_PARSER_H

#include <string_view>

#include <utility>

#include <cstring>

/* For now we have this one here */

#define MAX_HEADERS 10

namespace uWS {

    // should be templated on whether it needs at lest one header (http), or not (multipart)

    static inline unsigned int getHeaders(char *postPaddedBuffer, char *end, std::pair<std::string_view, std::string_view> *headers) {

        char *preliminaryKey, *preliminaryValue, *start = postPaddedBuffer;

        for (unsigned int i = 0; i < MAX_HEADERS; i++) {

            for (preliminaryKey = postPaddedBuffer; (*postPaddedBuffer != ':') & (*(unsigned char *)postPaddedBuffer > 32); *(postPaddedBuffer++) |= 32);

            if (*postPaddedBuffer == '\r') {

                if ((postPaddedBuffer != end) & (postPaddedBuffer[1] == '\n') /* & (i > 0) */) { // multipart does not require any headers like http does

                    headers->first = std::string_view(nullptr, 0);

                    return (unsigned int) ((postPaddedBuffer + 2) - start);

                } else {

                    return 0;

                }

            } else {

                headers->first = std::string_view(preliminaryKey, (size_t) (postPaddedBuffer - preliminaryKey));

                for (postPaddedBuffer++; (*postPaddedBuffer == ':' || *(unsigned char *)postPaddedBuffer < 33) && *postPaddedBuffer != '\r'; postPaddedBuffer++);

                preliminaryValue = postPaddedBuffer;

                postPaddedBuffer = (char *) memchr(postPaddedBuffer, '\r', end - postPaddedBuffer);

                if (postPaddedBuffer && postPaddedBuffer[1] == '\n') {

                    headers->second = std::string_view(preliminaryValue, (size_t) (postPaddedBuffer - preliminaryValue));

                    postPaddedBuffer += 2;

                    headers++;

                } else {

                    return 0;

                }

            }

        }

        return 0;

    }

}

#endif