/*

 * Copyright (c) 2014 DeNA Co., Ltd.

 *

 * 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 <stddef.h>

#include <stdio.h>

#include "h2o.h"

static ssize_t add_header(h2o_mem_pool_t *pool, h2o_headers_t *headers, h2o_iovec_t *name, const char *orig_name, const char *value,

                          size_t value_len, h2o_header_flags_t flags)

{

    h2o_header_t *slot;

    h2o_vector_reserve(pool, headers, headers->size + 1);

    slot = headers->entries + headers->size++;

    slot->name = name;

    slot->value.base = (char *)value;

    slot->value.len = value_len;

    slot->orig_name = orig_name ? h2o_strdup(pool, orig_name, name->len).base : NULL;

    slot->flags = flags;

    return headers->size - 1;

}

static inline h2o_iovec_t *alloc_and_init_iovec(h2o_mem_pool_t *pool, const char *base, size_t len)

{

    h2o_iovec_t *iov = h2o_mem_alloc_pool(pool, *iov, 1);

    iov->base = (char *)base;

    iov->len = len;

    return iov;

}

ssize_t h2o_find_header(const h2o_headers_t *headers, const h2o_token_t *token, ssize_t cursor)

{

    for (++cursor; cursor < headers->size; ++cursor) {

        if (headers->entries[cursor].name == &token->buf) {

            return cursor;

        }

    }

    return -1;

}

ssize_t h2o_find_header_by_str(const h2o_headers_t *headers, const char *name, size_t name_len, ssize_t cursor)

{

    for (++cursor; cursor < headers->size; ++cursor) {

        h2o_header_t *t = headers->entries + cursor;

        if (h2o_memis(t->name->base, t->name->len, name, name_len)) {

            return cursor;

        }

    }

    return -1;

}

ssize_t h2o_add_header(h2o_mem_pool_t *pool, h2o_headers_t *headers, const h2o_token_t *token, const char *orig_name,

                       const char *value, size_t value_len)

{

    return add_header(pool, headers, (h2o_iovec_t *)&token->buf, orig_name, value, value_len, (h2o_header_flags_t){0});

}

ssize_t h2o_add_header_by_str(h2o_mem_pool_t *pool, h2o_headers_t *headers, const char *lowercase_name, size_t lowercase_name_len,

                              int maybe_token, const char *orig_name, const char *value, size_t value_len)

{

    if (maybe_token) {

        const h2o_token_t *token = h2o_lookup_token(lowercase_name, lowercase_name_len);

        if (token != NULL) {

            return add_header(pool, headers, (h2o_iovec_t *)token, orig_name, value, value_len, (h2o_header_flags_t){0});

        }

    }

    return add_header(pool, headers, alloc_and_init_iovec(pool, lowercase_name, lowercase_name_len), orig_name, value, value_len,

                      (h2o_header_flags_t){0});

}

ssize_t h2o_set_header(h2o_mem_pool_t *pool, h2o_headers_t *headers, const h2o_token_t *token, const char *value, size_t value_len,

                       int overwrite_if_exists)

{

    ssize_t cursor = h2o_find_header(headers, token, -1);

    if (cursor != -1) {

        if (overwrite_if_exists) {

            headers->entries[cursor].value = h2o_iovec_init(value, value_len);

        }

        return cursor;

    } else {

        return h2o_add_header(pool, headers, token, NULL, value, value_len);

    }

}

ssize_t h2o_set_header_by_str(h2o_mem_pool_t *pool, h2o_headers_t *headers, const char *lowercase_name, size_t lowercase_name_len,

                              int maybe_token, const char *value, size_t value_len, int overwrite_if_exists)

{

    ssize_t cursor;

    if (maybe_token) {

        const h2o_token_t *token = h2o_lookup_token(lowercase_name, lowercase_name_len);

        if (token != NULL) {

            return h2o_set_header(pool, headers, token, value, value_len, overwrite_if_exists);

        }

    }

    cursor = h2o_find_header_by_str(headers, lowercase_name, lowercase_name_len, -1);

    if (cursor != -1) {

        if (overwrite_if_exists) {

            headers->entries[cursor].value = h2o_iovec_init(value, value_len);

        }

        return cursor;

    } else {

        return add_header(pool, headers, alloc_and_init_iovec(pool, lowercase_name, lowercase_name_len), NULL, value, value_len,

                          (h2o_header_flags_t){0});

    }

}

ssize_t h2o_set_header_token(h2o_mem_pool_t *pool, h2o_headers_t *headers, const h2o_token_t *token, const char *value,

                             size_t value_len)

{

    ssize_t found = -1;

    size_t i;

    for (i = 0; i != headers->size; ++i) {

        if (headers->entries[i].name == &token->buf) {

            if (h2o_contains_token(headers->entries[i].value.base, headers->entries[i].value.len, value, value_len, ','))

                return -1;

            found = i;

        }

    }

    if (found != -1) {

        h2o_header_t *dest = headers->entries + found;

        dest->value = h2o_concat(pool, dest->value, h2o_iovec_init(H2O_STRLIT(", ")), h2o_iovec_init(value, value_len));

        return found;

    } else {

        return h2o_add_header(pool, headers, token, NULL, value, value_len);

    }

}

ssize_t h2o_delete_header(h2o_headers_t *headers, ssize_t cursor)

{

    assert(cursor != -1);

    --headers->size;

    memmove(headers->entries + cursor, headers->entries + cursor + 1, sizeof(h2o_header_t) * (headers->size - cursor));

    return cursor;

}