/*
 * Copyright (c) 2013, Institute for Pervasive Computing, ETH Zurich
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the Institute 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 INSTITUTE 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 INSTITUTE 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.
 *
 * This file is part of the Contiki operating system.
 */

/**
 * \file
 *      An implementation of the Constrained Application Protocol (RFC).
 * \author
 *      Matthias Kovatsch <kovatsch@inf.ethz.ch>
 */

#include <string.h>
#include <stdio.h>
//#include "contiki.h"
//#include "sys/cc.h"
//#include "contiki-net.h"

#include "bh_common.h"
#include "er-coap.h"
/*#include "er-coap-transactions.h"*/

#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#define PRINT6ADDR(addr) PRINTF("[%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x]", ((uint8_t *)addr)[0], ((uint8_t *)addr)[1], ((uint8_t *)addr)[2], ((uint8_t *)addr)[3], ((uint8_t *)addr)[4], ((uint8_t *)addr)[5], ((uint8_t *)addr)[6], ((uint8_t *)addr)[7], ((uint8_t *)addr)[8], ((uint8_t *)addr)[9], ((uint8_t *)addr)[10], ((uint8_t *)addr)[11], ((uint8_t *)addr)[12], ((uint8_t *)addr)[13], ((uint8_t *)addr)[14], ((uint8_t *)addr)[15])
#define PRINTLLADDR(lladdr) PRINTF("[%02x:%02x:%02x:%02x:%02x:%02x]", (lladdr)->addr[0], (lladdr)->addr[1], (lladdr)->addr[2], (lladdr)->addr[3], (lladdr)->addr[4], (lladdr)->addr[5])
#else
#define PRINTF(...)
#define PRINT6ADDR(addr)
#define PRINTLLADDR(addr)
#endif

/*---------------------------------------------------------------------------*/
/*- Variables ---------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
static uint16_t current_mid = 0;

coap_status_t erbium_status_code = NO_ERROR;
char *coap_error_message = "";
/*---------------------------------------------------------------------------*/
/*- Local helper functions --------------------------------------------------*/
/*---------------------------------------------------------------------------*/
uint16_t coap_log_2(uint16_t value)
{
    uint16_t result = 0;

    do {
        value = value >> 1;
        result++;
    } while (value);

    return result ? result - 1 : result;
}
/*---------------------------------------------------------------------------*/
uint32_t coap_parse_int_option(uint8_t *bytes, size_t length)
{
    uint32_t var = 0;
    int i = 0;

    while (i < length) {
        var <<= 8;
        var |= bytes[i++];
    }
    return var;
}
/*---------------------------------------------------------------------------*/
static uint8_t coap_option_nibble(unsigned int value)
{
    if (value < 13) {
        return value;
    } else if (value <= 0xFF + 13) {
        return 13;
    } else {
        return 14;
    }
}
/*---------------------------------------------------------------------------*/
static size_t coap_set_option_header(unsigned int delta, size_t length,
        uint8_t *buffer)
{
    size_t written = 0;

    buffer[0] = coap_option_nibble(delta) << 4 | coap_option_nibble(length);

    /* avoids code duplication without function overhead */
    unsigned int *x = &delta;

    do {
        if (*x > 268) {
            buffer[++written] = (*x - 269) >> 8;
            buffer[++written] = (*x - 269);
        } else if (*x > 12) {
            buffer[++written] = (*x - 13);
        }
    } while (x != (unsigned int*) &length && (x = (unsigned int*) &length));

    PRINTF("WRITTEN %u B opt header\n", 1 + written);

    return ++written;
}
/*---------------------------------------------------------------------------*/
size_t coap_serialize_int_option(unsigned int number,
        unsigned int current_number, uint8_t *buffer, uint32_t value)
{
    size_t i = 0;

    if (0xFF000000 & value) {
        ++i;
    }
    if (0xFFFF0000 & value) {
        ++i;
    }
    if (0xFFFFFF00 & value) {
        ++i;
    }
    // if(0xFFFFFFFF & value) {
    ++i;
    // }
    PRINTF("OPTION %u (delta %u, len %u)\n", number, number - current_number,
            i);

    i = coap_set_option_header(number - current_number, i, buffer);

    if (0xFF000000 & value) {
        buffer[i++] = (uint8_t)(value >> 24);
    }
    if (0xFFFF0000 & value) {
        buffer[i++] = (uint8_t)(value >> 16);
    }
    if (0xFFFFFF00 & value) {
        buffer[i++] = (uint8_t)(value >> 8);
    }
    // if(0xFFFFFFFF & value) {
    buffer[i++] = (uint8_t)(value);
    // }
    return i;
}
/*---------------------------------------------------------------------------*/
size_t coap_serialize_array_option(unsigned int number,
        unsigned int current_number, uint8_t *buffer, uint8_t *array,
        size_t length, char split_char)
{
    size_t i = 0;

    PRINTF("ARRAY type %u, len %u, full [%.*s]\n", number, length, length,
            array);

    if (split_char != '\0') {
        int j;
        uint8_t *part_start = array;
        uint8_t *part_end = NULL;
        size_t temp_length;

        for (j = 0; j <= length + 1; ++j) {
            PRINTF("STEP %u/%u (%c)\n", j, length, array[j]);
            if (array[j] == split_char || j == length) {
                part_end = array + j;
                temp_length = part_end - part_start;

                i += coap_set_option_header(number - current_number,
                        temp_length, &buffer[i]);
                bh_memcpy_s(&buffer[i], temp_length, part_start, temp_length);
                i += temp_length;

                PRINTF("OPTION type %u, delta %u, len %u, part [%.*s]\n", number,
                        number - current_number, i, temp_length, part_start);

                ++j; /* skip the splitter */
                current_number = number;
                part_start = array + j;
            }
        } /* for */
    } else {
        i += coap_set_option_header(number - current_number, length,
                &buffer[i]);
        bh_memcpy_s(&buffer[i], length, array, length);
        i += length;

        PRINTF("OPTION type %u, delta %u, len %u\n", number,
                number - current_number, length);
    }

    return i;
}
/*---------------------------------------------------------------------------*/
void coap_merge_multi_option(char **dst, size_t *dst_len, uint8_t *option,
        size_t option_len, char separator)
{
    /* merge multiple options */
    if (*dst_len > 0) {
        /* dst already contains an option: concatenate */
        (*dst)[*dst_len] = separator;
        *dst_len += 1;

        /* memmove handles 2-byte option headers */
        memmove((*dst) + (*dst_len), option, option_len);

        *dst_len += option_len;
    } else {
        /* dst is empty: set to option */
        *dst = (char *) option;
        *dst_len = option_len;
    }
}
/*---------------------------------------------------------------------------*/
#if 0
static int
coap_get_variable(const char *buffer, size_t length, const char *name,
        const char **output)
{
    const char *start = NULL;
    const char *end = NULL;
    const char *value_end = NULL;
    size_t name_len = 0;

    /*initialize the output buffer first */
    *output = 0;

    name_len = strlen(name);
    end = buffer + length;

    for(start = buffer; start + name_len < end; ++start) {
        if((start == buffer || start[-1] == '&') && start[name_len] == '='
                && strncmp(name, start, name_len) == 0) {

            /* Point start to variable value */
            start += name_len + 1;

            /* Point end to the end of the value */
            value_end = (const char *)memchr(start, '&', end - start);
            if(value_end == NULL) {
                value_end = end;
            }
            *output = start;

            return value_end - start;
        }
    }
    return 0;
}
#endif
/*---------------------------------------------------------------------------*/
/*- Internal API ------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/

/*---------------------------------------------------------------------------*/
uint16_t coap_get_mid()
{
    return ++current_mid;
}

/*---------------------------------------------------------------------------*/
void coap_init_message(void *packet, coap_message_type_t type, uint8_t code,
        uint16_t mid)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    /* Important thing */
    memset(coap_pkt, 0, sizeof(coap_packet_t));

    coap_pkt->type = type;
    coap_pkt->code = code;
    coap_pkt->mid = mid;
}
#if 0
/*---------------------------------------------------------------------------*/
size_t
coap_serialize_message(void *packet, uint8_t *buffer)
{
    coap_packet_t *const coap_pkt = (coap_packet_t *)packet;
    uint8_t *option;
    unsigned int current_number = 0;

    /* Initialize */
    coap_pkt->buffer = buffer;
    coap_pkt->version = 1;

    PRINTF("-Serializing MID %u to %p, ", coap_pkt->mid, coap_pkt->buffer);

    /* set header fields */
    coap_pkt->buffer[0] = 0x00;
    coap_pkt->buffer[0] |= COAP_HEADER_VERSION_MASK
    & (coap_pkt->version) << COAP_HEADER_VERSION_POSITION;
    coap_pkt->buffer[0] |= COAP_HEADER_TYPE_MASK
    & (coap_pkt->type) << COAP_HEADER_TYPE_POSITION;
    coap_pkt->buffer[0] |= COAP_HEADER_TOKEN_LEN_MASK
    & (coap_pkt->token_len) << COAP_HEADER_TOKEN_LEN_POSITION;
    coap_pkt->buffer[1] = coap_pkt->code;
    coap_pkt->buffer[2] = (uint8_t)((coap_pkt->mid) >> 8);
    coap_pkt->buffer[3] = (uint8_t)(coap_pkt->mid);

    /* empty packet, dont need to do more stuff */
    if(!coap_pkt->code) {
        PRINTF("-Done serializing empty message at %p-\n", option);
        return 4;
    }

    /* set Token */
    PRINTF("Token (len %u)", coap_pkt->token_len);
    option = coap_pkt->buffer + COAP_HEADER_LEN;
    for(current_number = 0; current_number < coap_pkt->token_len;
            ++current_number) {
        PRINTF(" %02X", coap_pkt->token[current_number]);
        *option = coap_pkt->token[current_number];
        ++option;
    }
    PRINTF("-\n");

    /* Serialize options */
    current_number = 0;

    PRINTF("-Serializing options at %p-\n", option);

    /* The options must be serialized in the order of their number */
    COAP_SERIALIZE_BYTE_OPTION(COAP_OPTION_IF_MATCH, if_match, "If-Match");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_URI_HOST, uri_host, '\0',
            "Uri-Host");
    COAP_SERIALIZE_BYTE_OPTION(COAP_OPTION_ETAG, etag, "ETag");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_IF_NONE_MATCH,
            content_format -
            coap_pkt->
            content_format /* hack to get a zero field */,
            "If-None-Match");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_OBSERVE, observe, "Observe");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_URI_PORT, uri_port, "Uri-Port");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_LOCATION_PATH, location_path, '/',
            "Location-Path");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_URI_PATH, uri_path, '/',
            "Uri-Path");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_CONTENT_FORMAT, content_format,
            "Content-Format");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_MAX_AGE, max_age, "Max-Age");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_URI_QUERY, uri_query, '&',
            "Uri-Query");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_ACCEPT, accept, "Accept");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_LOCATION_QUERY, location_query,
            '&', "Location-Query");
    COAP_SERIALIZE_BLOCK_OPTION(COAP_OPTION_BLOCK2, block2, "Block2");
    COAP_SERIALIZE_BLOCK_OPTION(COAP_OPTION_BLOCK1, block1, "Block1");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_SIZE2, size2, "Size2");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_PROXY_URI, proxy_uri, '\0',
            "Proxy-Uri");
    COAP_SERIALIZE_STRING_OPTION(COAP_OPTION_PROXY_SCHEME, proxy_scheme, '\0',
            "Proxy-Scheme");
    COAP_SERIALIZE_INT_OPTION(COAP_OPTION_SIZE1, size1, "Size1");

    PRINTF("-Done serializing at %p----\n", option);

    /* Pack payload */
    if((option - coap_pkt->buffer) <= COAP_MAX_HEADER_SIZE) {
        /* Payload marker */
        if(coap_pkt->payload_len) {
            *option = 0xFF;
            ++option;
        }
        memmove(option, coap_pkt->payload, coap_pkt->payload_len);
    } else {
        /* an error occurred: caller must check for !=0 */
        coap_pkt->buffer = NULL;
        coap_error_message = "Serialized header exceeds COAP_MAX_HEADER_SIZE";
        return 0;
    }

    PRINTF("-Done %u B (header len %u, payload len %u)-\n",
            coap_pkt->payload_len + option - buffer, option - buffer,
            coap_pkt->payload_len);

    PRINTF("Dump [0x%02X %02X %02X %02X  %02X %02X %02X %02X]\n",
            coap_pkt->buffer[0],
            coap_pkt->buffer[1],
            coap_pkt->buffer[2],
            coap_pkt->buffer[3],
            coap_pkt->buffer[4],
            coap_pkt->buffer[5], coap_pkt->buffer[6], coap_pkt->buffer[7]
    );

    return (option - buffer) + coap_pkt->payload_len; /* packet length */
}

/*---------------------------------------------------------------------------*/
coap_status_t
coap_parse_message(void *packet, uint8_t *data, uint16_t data_len)
{
    coap_packet_t *const coap_pkt = (coap_packet_t *)packet;

    /* initialize packet */
    memset(coap_pkt, 0, sizeof(coap_packet_t));

    /* pointer to packet bytes */
    coap_pkt->buffer = data;

    /* parse header fields */
    coap_pkt->version = (COAP_HEADER_VERSION_MASK & coap_pkt->buffer[0])
    >> COAP_HEADER_VERSION_POSITION;
    coap_pkt->type = (COAP_HEADER_TYPE_MASK & coap_pkt->buffer[0])
    >> COAP_HEADER_TYPE_POSITION;
    coap_pkt->token_len =
    MIN(COAP_TOKEN_LEN,
            (COAP_HEADER_TOKEN_LEN_MASK & coap_pkt->
                    buffer[0]) >> COAP_HEADER_TOKEN_LEN_POSITION);
    coap_pkt->code = coap_pkt->buffer[1];
    coap_pkt->mid = coap_pkt->buffer[2] << 8 | coap_pkt->buffer[3];

    if(coap_pkt->version != 1) {
        coap_error_message = "CoAP version must be 1";
        return BAD_REQUEST_4_00;
    }

    uint8_t *current_option = data + COAP_HEADER_LEN;

    bh_memcpy_s(coap_pkt->token, COAP_TOKEN_LEN, current_option, coap_pkt->token_len);
    PRINTF("Token (len %u) [0x%02X%02X%02X%02X%02X%02X%02X%02X]\n",
            coap_pkt->token_len, coap_pkt->token[0], coap_pkt->token[1],
            coap_pkt->token[2], coap_pkt->token[3], coap_pkt->token[4],
            coap_pkt->token[5], coap_pkt->token[6], coap_pkt->token[7]
    ); /*FIXME always prints 8 bytes */

    /* parse options */
    memset(coap_pkt->options, 0, sizeof(coap_pkt->options));
    current_option += coap_pkt->token_len;

    unsigned int option_number = 0;
    unsigned int option_delta = 0;
    size_t option_length = 0;

    while(current_option < data + data_len) {
        /* payload marker 0xFF, currently only checking for 0xF* because rest is reserved */
        if((current_option[0] & 0xF0) == 0xF0) {
            coap_pkt->payload = ++current_option;
            coap_pkt->payload_len = data_len - (coap_pkt->payload - data);

            /* also for receiving, the Erbium upper bound is REST_MAX_CHUNK_SIZE */
            if(coap_pkt->payload_len > REST_MAX_CHUNK_SIZE) {
                coap_pkt->payload_len = REST_MAX_CHUNK_SIZE;
                /* null-terminate payload */
            }
            coap_pkt->payload[coap_pkt->payload_len] = '\0';

            break;
        }

        option_delta = current_option[0] >> 4;
        option_length = current_option[0] & 0x0F;
        ++current_option;

        /* avoids code duplication without function overhead */
        unsigned int *x = &option_delta;

        do {
            if(*x == 13) {
                *x += current_option[0];
                ++current_option;
            } else if(*x == 14) {
                *x += 255;
                *x += current_option[0] << 8;
                ++current_option;
                *x += current_option[0];
                ++current_option;
            }
        }while(x != (unsigned int*)&option_length && (x = (unsigned int*)&option_length));

        option_number += option_delta;

        PRINTF("OPTION %u (delta %u, len %u): ", option_number, option_delta,
                option_length);

        SET_OPTION(coap_pkt, option_number);

        switch(option_number) {
            case COAP_OPTION_CONTENT_FORMAT:
            coap_pkt->content_format = coap_parse_int_option(current_option,
                    option_length);
            PRINTF("Content-Format [%u]\n", coap_pkt->content_format);
            break;
            case COAP_OPTION_MAX_AGE:
            coap_pkt->max_age = coap_parse_int_option(current_option,
                    option_length);
            PRINTF("Max-Age [%lu]\n", coap_pkt->max_age);
            break;
            case COAP_OPTION_ETAG:
            coap_pkt->etag_len = MIN(COAP_ETAG_LEN, option_length);
            bh_memcpy_s(coap_pkt->etag, COAP_ETAG_LEN, current_option, coap_pkt->etag_len);
            PRINTF("ETag %u [0x%02X%02X%02X%02X%02X%02X%02X%02X]\n",
                    coap_pkt->etag_len, coap_pkt->etag[0], coap_pkt->etag[1],
                    coap_pkt->etag[2], coap_pkt->etag[3], coap_pkt->etag[4],
                    coap_pkt->etag[5], coap_pkt->etag[6], coap_pkt->etag[7]
            ); /*FIXME always prints 8 bytes */
            break;
            case COAP_OPTION_ACCEPT:
            coap_pkt->accept = coap_parse_int_option(current_option, option_length);
            PRINTF("Accept [%u]\n", coap_pkt->accept);
            break;
            case COAP_OPTION_IF_MATCH:
            /* TODO support multiple ETags */
            coap_pkt->if_match_len = MIN(COAP_ETAG_LEN, option_length);
            bh_memcpy_s(coap_pkt->if_match, COAP_ETAG_LEN, current_option, coap_pkt->if_match_len);
            PRINTF("If-Match %u [0x%02X%02X%02X%02X%02X%02X%02X%02X]\n",
                    coap_pkt->if_match_len, coap_pkt->if_match[0],
                    coap_pkt->if_match[1], coap_pkt->if_match[2],
                    coap_pkt->if_match[3], coap_pkt->if_match[4],
                    coap_pkt->if_match[5], coap_pkt->if_match[6],
                    coap_pkt->if_match[7]
            ); /* FIXME always prints 8 bytes */
            break;
            case COAP_OPTION_IF_NONE_MATCH:
            coap_pkt->if_none_match = 1;
            PRINTF("If-None-Match\n");
            break;

            case COAP_OPTION_PROXY_URI:
#if COAP_PROXY_OPTION_PROCESSING
            coap_pkt->proxy_uri = (char *)current_option;
            coap_pkt->proxy_uri_len = option_length;
#endif
            PRINTF("Proxy-Uri NOT IMPLEMENTED [%.*s]\n", coap_pkt->proxy_uri_len,
                    coap_pkt->proxy_uri);
            coap_error_message = "This is a constrained server (Contiki)";
            return PROXYING_NOT_SUPPORTED_5_05;
            break;
            case COAP_OPTION_PROXY_SCHEME:
#if COAP_PROXY_OPTION_PROCESSING
            coap_pkt->proxy_scheme = (char *)current_option;
            coap_pkt->proxy_scheme_len = option_length;
#endif
            PRINTF("Proxy-Scheme NOT IMPLEMENTED [%.*s]\n",
                    coap_pkt->proxy_scheme_len, coap_pkt->proxy_scheme);
            coap_error_message = "This is a constrained server (Contiki)";
            return PROXYING_NOT_SUPPORTED_5_05;
            break;

            case COAP_OPTION_URI_HOST:
            coap_pkt->uri_host = (char *)current_option;
            coap_pkt->uri_host_len = option_length;
            PRINTF("Uri-Host [%.*s]\n", coap_pkt->uri_host_len, coap_pkt->uri_host);
            break;
            case COAP_OPTION_URI_PORT:
            coap_pkt->uri_port = coap_parse_int_option(current_option,
                    option_length);
            PRINTF("Uri-Port [%u]\n", coap_pkt->uri_port);
            break;
            case COAP_OPTION_URI_PATH:
            /* coap_merge_multi_option() operates in-place on the IPBUF, but final packet field should be const string -> cast to string */
            coap_merge_multi_option((char **)&(coap_pkt->uri_path),
                    &(coap_pkt->uri_path_len), current_option,
                    option_length, '/');
            PRINTF("Uri-Path [%.*s]\n", coap_pkt->uri_path_len, coap_pkt->uri_path);
            break;
            case COAP_OPTION_URI_QUERY:
            /* coap_merge_multi_option() operates in-place on the IPBUF, but final packet field should be const string -> cast to string */
            coap_merge_multi_option((char **)&(coap_pkt->uri_query),
                    &(coap_pkt->uri_query_len), current_option,
                    option_length, '&');
            PRINTF("Uri-Query [%.*s]\n", coap_pkt->uri_query_len,
                    coap_pkt->uri_query);
            break;

            case COAP_OPTION_LOCATION_PATH:
            /* coap_merge_multi_option() operates in-place on the IPBUF, but final packet field should be const string -> cast to string */
            coap_merge_multi_option((char **)&(coap_pkt->location_path),
                    &(coap_pkt->location_path_len), current_option,
                    option_length, '/');
            PRINTF("Location-Path [%.*s]\n", coap_pkt->location_path_len,
                    coap_pkt->location_path);
            break;
            case COAP_OPTION_LOCATION_QUERY:
            /* coap_merge_multi_option() operates in-place on the IPBUF, but final packet field should be const string -> cast to string */
            coap_merge_multi_option((char **)&(coap_pkt->location_query),
                    &(coap_pkt->location_query_len), current_option,
                    option_length, '&');
            PRINTF("Location-Query [%.*s]\n", coap_pkt->location_query_len,
                    coap_pkt->location_query);
            break;

            case COAP_OPTION_OBSERVE:
            coap_pkt->observe = coap_parse_int_option(current_option,
                    option_length);
            PRINTF("Observe [%lu]\n", coap_pkt->observe);
            break;
            case COAP_OPTION_BLOCK2:
            coap_pkt->block2_num = coap_parse_int_option(current_option,
                    option_length);
            coap_pkt->block2_more = (coap_pkt->block2_num & 0x08) >> 3;
            coap_pkt->block2_size = 16 << (coap_pkt->block2_num & 0x07);
            coap_pkt->block2_offset = (coap_pkt->block2_num & ~0x0000000F)
            << (coap_pkt->block2_num & 0x07);
            coap_pkt->block2_num >>= 4;
            PRINTF("Block2 [%lu%s (%u B/blk)]\n", coap_pkt->block2_num,
                    coap_pkt->block2_more ? "+" : "", coap_pkt->block2_size);
            break;
            case COAP_OPTION_BLOCK1:
            coap_pkt->block1_num = coap_parse_int_option(current_option,
                    option_length);
            coap_pkt->block1_more = (coap_pkt->block1_num & 0x08) >> 3;
            coap_pkt->block1_size = 16 << (coap_pkt->block1_num & 0x07);
            coap_pkt->block1_offset = (coap_pkt->block1_num & ~0x0000000F)
            << (coap_pkt->block1_num & 0x07);
            coap_pkt->block1_num >>= 4;
            PRINTF("Block1 [%lu%s (%u B/blk)]\n", coap_pkt->block1_num,
                    coap_pkt->block1_more ? "+" : "", coap_pkt->block1_size);
            break;
            case COAP_OPTION_SIZE2:
            coap_pkt->size2 = coap_parse_int_option(current_option, option_length);
            PRINTF("Size2 [%lu]\n", coap_pkt->size2);
            break;
            case COAP_OPTION_SIZE1:
            coap_pkt->size1 = coap_parse_int_option(current_option, option_length);
            PRINTF("Size1 [%lu]\n", coap_pkt->size1);
            break;
            default:
            PRINTF("unknown (%u)\n", option_number);
            /* check if critical (odd) */
            if(option_number & 1) {
                coap_error_message = "Unsupported critical option";
                return BAD_OPTION_4_02;
            }
        }

        current_option += option_length;
    } /* for */
    PRINTF("-Done parsing-------\n");

    return NO_ERROR;
}
/*---------------------------------------------------------------------------*/
/*- REST Engine API ---------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
int
coap_get_query_variable(void *packet, const char *name, const char **output)
{
    coap_packet_t *const coap_pkt = (coap_packet_t *)packet;

    if(IS_OPTION(coap_pkt, COAP_OPTION_URI_QUERY)) {
        return coap_get_variable(coap_pkt->uri_query, coap_pkt->uri_query_len,
                name, output);
    }
    return 0;
}
int
coap_get_post_variable(void *packet, const char *name, const char **output)
{
    coap_packet_t *const coap_pkt = (coap_packet_t *)packet;

    if(coap_pkt->payload_len) {
        return coap_get_variable((const char *)coap_pkt->payload,
                coap_pkt->payload_len, name, output);
    }
    return 0;
}
#endif
/*---------------------------------------------------------------------------*/
int coap_set_status_code(void *packet, unsigned int code)
{
    if (code <= 0xFF) {
        ((coap_packet_t *) packet)->code = (uint8_t) code;
        return 1;
    } else {
        return 0;
    }
}
/*---------------------------------------------------------------------------*/
int coap_set_token(void *packet, const uint8_t *token, size_t token_len)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->token_len = MIN(COAP_TOKEN_LEN, token_len);
    bh_memcpy_s(coap_pkt->token, COAP_TOKEN_LEN, token, coap_pkt->token_len);

    return coap_pkt->token_len;
}
/*---------------------------------------------------------------------------*/
/*- CoAP REST Implementation API --------------------------------------------*/
/*---------------------------------------------------------------------------*/
int coap_get_header_content_format(void *packet, unsigned int *format)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_CONTENT_FORMAT)) {
        return 0;
    }
    *format = coap_pkt->content_format;
    return 1;
}
int coap_set_header_content_format(void *packet, unsigned int format)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->content_format = (coap_content_format_t) format;
    SET_OPTION(coap_pkt, COAP_OPTION_CONTENT_FORMAT);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_accept(void *packet, unsigned int *accept)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_ACCEPT)) {
        return 0;
    }
    *accept = coap_pkt->accept;
    return 1;
}
int coap_set_header_accept(void *packet, unsigned int accept)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->accept = (coap_content_format_t) accept;
    SET_OPTION(coap_pkt, COAP_OPTION_ACCEPT);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_max_age(void *packet, uint32_t *age)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_MAX_AGE)) {
        *age = COAP_DEFAULT_MAX_AGE;
    } else {
        *age = coap_pkt->max_age;
    }
    return 1;
}
int coap_set_header_max_age(void *packet, uint32_t age)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->max_age = age;
    SET_OPTION(coap_pkt, COAP_OPTION_MAX_AGE);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_etag(void *packet, const uint8_t **etag)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_ETAG)) {
        return 0;
    }
    *etag = coap_pkt->etag;
    return coap_pkt->etag_len;
}
int coap_set_header_etag(void *packet, const uint8_t *etag, size_t etag_len)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->etag_len = MIN(COAP_ETAG_LEN, etag_len);
    bh_memcpy_s(coap_pkt->etag, COAP_ETAG_LEN, etag, coap_pkt->etag_len);

    SET_OPTION(coap_pkt, COAP_OPTION_ETAG);
    return coap_pkt->etag_len;
}
/*---------------------------------------------------------------------------*/
/*FIXME support multiple ETags */
int coap_get_header_if_match(void *packet, const uint8_t **etag)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_IF_MATCH)) {
        return 0;
    }
    *etag = coap_pkt->if_match;
    return coap_pkt->if_match_len;
}
int coap_set_header_if_match(void *packet, const uint8_t *etag, size_t etag_len)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->if_match_len = MIN(COAP_ETAG_LEN, etag_len);
    bh_memcpy_s(coap_pkt->if_match, COAP_ETAG_LEN, etag,
            coap_pkt->if_match_len);

    SET_OPTION(coap_pkt, COAP_OPTION_IF_MATCH);
    return coap_pkt->if_match_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_if_none_match(void *packet)
{
    return IS_OPTION((coap_packet_t *)packet,
            COAP_OPTION_IF_NONE_MATCH) ? 1 : 0;
}
int coap_set_header_if_none_match(void *packet)
{
    SET_OPTION((coap_packet_t * )packet, COAP_OPTION_IF_NONE_MATCH);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_proxy_uri(void *packet, const char **uri)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_PROXY_URI)) {
        return 0;
    }
    *uri = coap_pkt->proxy_uri;
    return coap_pkt->proxy_uri_len;
}
int coap_set_header_proxy_uri(void *packet, const char *uri)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    /*TODO Provide alternative that sets Proxy-Scheme and Uri-* options and provide er-coap-conf define */

    coap_pkt->proxy_uri = uri;
    coap_pkt->proxy_uri_len = strlen(uri);

    SET_OPTION(coap_pkt, COAP_OPTION_PROXY_URI);
    return coap_pkt->proxy_uri_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_uri_host(void *packet, const char **host)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_URI_HOST)) {
        return 0;
    }
    *host = coap_pkt->uri_host;
    return coap_pkt->uri_host_len;
}
int coap_set_header_uri_host(void *packet, const char *host)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->uri_host = host;
    coap_pkt->uri_host_len = strlen(host);

    SET_OPTION(coap_pkt, COAP_OPTION_URI_HOST);
    return coap_pkt->uri_host_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_uri_path(void *packet, const char **path)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_URI_PATH)) {
        return 0;
    }
    *path = coap_pkt->uri_path;
    return coap_pkt->uri_path_len;
}
int coap_set_header_uri_path(void *packet, const char *path)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

//  while(path[0] == '/')
//    ++path;

    coap_pkt->uri_path = path;
    coap_pkt->uri_path_len = strlen(path);

    SET_OPTION(coap_pkt, COAP_OPTION_URI_PATH);
    return coap_pkt->uri_path_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_uri_query(void *packet, const char **query)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_URI_QUERY)) {
        return 0;
    }
    *query = coap_pkt->uri_query;
    return coap_pkt->uri_query_len;
}
int coap_set_header_uri_query(void *packet, const char *query)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    while (query[0] == '?')
        ++query;

    coap_pkt->uri_query = query;
    coap_pkt->uri_query_len = strlen(query);

    SET_OPTION(coap_pkt, COAP_OPTION_URI_QUERY);
    return coap_pkt->uri_query_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_location_path(void *packet, const char **path)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_LOCATION_PATH)) {
        return 0;
    }
    *path = coap_pkt->location_path;
    return coap_pkt->location_path_len;
}
int coap_set_header_location_path(void *packet, const char *path)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    char *query;

    while (path[0] == '/')
        ++path;

    if ((query = strchr(path, '?'))) {
        coap_set_header_location_query(packet, query + 1);
        coap_pkt->location_path_len = query - path;
    } else {
        coap_pkt->location_path_len = strlen(path);
    }
    coap_pkt->location_path = path;

    if (coap_pkt->location_path_len > 0) {
        SET_OPTION(coap_pkt, COAP_OPTION_LOCATION_PATH);
    }
    return coap_pkt->location_path_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_location_query(void *packet, const char **query)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_LOCATION_QUERY)) {
        return 0;
    }
    *query = coap_pkt->location_query;
    return coap_pkt->location_query_len;
}
int coap_set_header_location_query(void *packet, const char *query)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    while (query[0] == '?')
        ++query;

    coap_pkt->location_query = query;
    coap_pkt->location_query_len = strlen(query);

    SET_OPTION(coap_pkt, COAP_OPTION_LOCATION_QUERY);
    return coap_pkt->location_query_len;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_observe(void *packet, uint32_t *observe)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_OBSERVE)) {
        return 0;
    }
    *observe = coap_pkt->observe;
    return 1;
}
int coap_set_header_observe(void *packet, uint32_t observe)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->observe = observe;
    SET_OPTION(coap_pkt, COAP_OPTION_OBSERVE);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_block2(void *packet, uint32_t *num, uint8_t *more,
        uint32_t *size, uint32_t *offset)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_BLOCK2)) {
        return 0;
    }
    /* pointers may be NULL to get only specific block parameters */
    if (num != NULL) {
        *num = coap_pkt->block2_num;
    }
    if (more != NULL) {
        *more = coap_pkt->block2_more;
    }
    if (size != NULL) {
        *size = coap_pkt->block2_size;
    }
    if (offset != NULL) {
        *offset = coap_pkt->block2_offset;
    }
    return 1;
}
int coap_set_header_block2(void *packet, uint32_t num, uint8_t more,
        uint32_t size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (size < 16) {
        return 0;
    }
    if (size > 2048) {
        return 0;
    }
    if (num > 0x0FFFFF) {
        return 0;
    }
    coap_pkt->block2_num = num;
    coap_pkt->block2_more = more ? 1 : 0;
    coap_pkt->block2_size = size;

    SET_OPTION(coap_pkt, COAP_OPTION_BLOCK2);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_block1(void *packet, uint32_t *num, uint8_t *more,
        uint16_t *size, uint32_t *offset)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_BLOCK1)) {
        return 0;
    }
    /* pointers may be NULL to get only specific block parameters */
    if (num != NULL) {
        *num = coap_pkt->block1_num;
    }
    if (more != NULL) {
        *more = coap_pkt->block1_more;
    }
    if (size != NULL) {
        *size = coap_pkt->block1_size;
    }
    if (offset != NULL) {
        *offset = coap_pkt->block1_offset;
    }
    return 1;
}
int coap_set_header_block1(void *packet, uint32_t num, uint8_t more,
        uint16_t size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (size < 16) {
        return 0;
    }
    if (size > 2048) {
        return 0;
    }
    if (num > 0x0FFFFF) {
        return 0;
    }
    coap_pkt->block1_num = num;
    coap_pkt->block1_more = more;
    coap_pkt->block1_size = size;

    SET_OPTION(coap_pkt, COAP_OPTION_BLOCK1);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_size2(void *packet, uint32_t *size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_SIZE2)) {
        return 0;
    }
    *size = coap_pkt->size2;
    return 1;
}
int coap_set_header_size2(void *packet, uint32_t size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->size2 = size;
    SET_OPTION(coap_pkt, COAP_OPTION_SIZE2);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_header_size1(void *packet, uint32_t *size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (!IS_OPTION(coap_pkt, COAP_OPTION_SIZE1)) {
        return 0;
    }
    *size = coap_pkt->size1;
    return 1;
}
int coap_set_header_size1(void *packet, uint32_t size)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->size1 = size;
    SET_OPTION(coap_pkt, COAP_OPTION_SIZE1);
    return 1;
}
/*---------------------------------------------------------------------------*/
int coap_get_payload(void *packet, const uint8_t **payload)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    if (coap_pkt->payload) {
        *payload = coap_pkt->payload;
        return coap_pkt->payload_len;
    } else {
        *payload = NULL;
        return 0;
    }
}
int coap_set_payload(void *packet, const void *payload, size_t length)
{
    coap_packet_t * const coap_pkt = (coap_packet_t *) packet;

    coap_pkt->payload = (uint8_t *) payload;
    coap_pkt->payload_len = MIN(REST_MAX_CHUNK_SIZE, length);

    return coap_pkt->payload_len;
}
/*---------------------------------------------------------------------------*/
