/*

 * Copyright (c) 2013 Tim Ruehsen

 * Copyright (c) 2015-2024 Free Software Foundation, Inc.

 *

 * This file is part of libwget.

 *

 * Libwget is free software: you can redistribute it and/or modify

 * it under the terms of the GNU Lesser General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * Libwget is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with libwget.  If not, see <https://www.gnu.org/licenses/>.

 *

 *

 * Extracting URLs from RSS feeds (https://cyber.harvard.edu/rss/rss.html)

 *

 * Changelog

 * 21.12.2013  Tim Ruehsen  created

 *

 */

#include <config.h>

#include <unistd.h>

#include <stdlib.h>

#include <string.h>

#include <c-ctype.h>

#include <wget.h>

#include "private.h"

struct rss_context {

  wget_vector

    *urls;

};

static void rss_get_url(void *context, int flags, const char *dir, const char *attr, const char *val, size_t len, size_t pos WGET_GCC_UNUSED)

{

  struct rss_context *ctx = context;

  wget_string * url;

  if (!val || !len)

    return;

  if ((flags & XML_FLG_ATTRIBUTE)) {

    if (!wget_strcasecmp_ascii(attr, "url") || !wget_strcasecmp_ascii(attr, "href")

      || !wget_strcasecmp_ascii(attr, "src") || !wget_strcasecmp_ascii(attr, "domain")

      || !wget_strcasecmp_ascii(attr, "xmlns") || !wget_strncasecmp_ascii(attr, "xmlns:", 6))

    {

      for (;len && c_isspace(*val); val++, len--); // skip leading spaces

      for (;len && c_isspace(val[len - 1]); len--);  // skip trailing spaces

      if (!(url = wget_malloc(sizeof(wget_string))))

        return;

      url->p = val;

      url->len = len;

      if (!ctx->urls)

        ctx->urls = wget_vector_create(32, NULL);

      wget_vector_add(ctx->urls, url);

    }

  }

  else if ((flags & XML_FLG_CONTENT)) {

    const char *elem = strrchr(dir, '/');

    if (elem) {

      elem++;

      if (!wget_strcasecmp_ascii(elem, "guid") || !wget_strcasecmp_ascii(elem, "link")

         || !wget_strcasecmp_ascii(elem, "comments") || !wget_strcasecmp_ascii(elem, "docs"))

      {

        for (;len && c_isspace(*val); val++, len--); // skip leading spaces

        for (;len && c_isspace(val[len - 1]); len--);  // skip trailing spaces

        // debug_printf("#2 %02X %s %s '%.*s' %zd\n", flags, dir, attr, (int) len, val, len);

        if (!(url = wget_malloc(sizeof(wget_string))))

          return;

        url->p = val;

        url->len = len;

        if (!ctx->urls)

          ctx->urls = wget_vector_create(32, NULL);

        wget_vector_add(ctx->urls, url);

      }

    }

  }

}

void wget_rss_get_urls_inline(const char *rss, wget_vector **urls)

{

  struct rss_context context = { .urls = NULL };

  wget_xml_parse_buffer(rss, rss_get_url, &context, XML_HINT_REMOVE_EMPTY_CONTENT);

  *urls = context.urls;

}