/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
 *
 * Copyright (C) 2014 Richard Hughes <richard@hughsie.com>
 *
 * Licensed under the GNU Lesser General Public License Version 2.1
 *
 * This library 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 2.1 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
 */

/**
 * SECTION:as-utils
 * @short_description: Helper functions that are used inside libappstream-glib
 * @include: appstream-glib.h
 * @stability: Stable
 *
 * These functions are used internally to libappstream-glib, and some may be
 * useful to user-applications.
 */

#include "config.h"

#include <string.h>
#include <libsoup/soup.h>

#include "as-cleanup.h"
#include "as-node.h"
#include "as-resources.h"
#include "as-utils.h"
#include "as-utils-private.h"

/**
 * as_strndup:
 * @text: the text to copy.
 * @text_len: the length of @text, or -1 if @text is NULL terminated.
 *
 * Copies a string, with an optional length argument.
 *
 * Returns: (transfer full): a newly allocated %NULL terminated string
 *
 * Since: 0.1.0
 **/
gchar *
as_strndup (const gchar *text, gssize text_len)
{
	if (text_len < 0)
		return g_strdup (text);
	return g_strndup (text, text_len);
}

/**
 * as_markup_convert_simple:
 * @markup: the text to copy.
 * @markup_len: the length of @markup, or -1 if @markup is NULL terminated.
 * @error: A #GError or %NULL
 *
 * Converts an XML description into a printable form.
 *
 * Returns: (transfer full): a newly allocated %NULL terminated string
 *
 * Since: 0.1.0
 **/
gchar *
as_markup_convert_simple (const gchar *markup,
			  gssize markup_len,
			  GError **error)
{
	GNode *tmp;
	GNode *tmp_c;
	_cleanup_free_string GString *str = NULL;
	_cleanup_unref_node GNode *root = NULL;
	const gchar *tag;
	const gchar *tag_c;

	/* is this actually markup */
	if (g_strstr_len (markup, markup_len, "<") == NULL)
		return as_strndup (markup, markup_len);

	/* load */
	root = as_node_from_xml (markup,
				 markup_len,
				 AS_NODE_FROM_XML_FLAG_NONE,
				 error);
	if (root == NULL)
		return NULL;

	/* format */
	str = g_string_sized_new (markup_len);
	for (tmp = root->children; tmp != NULL; tmp = tmp->next) {

		tag = as_node_get_name (tmp);
		if (g_strcmp0 (tag, "p") == 0) {
			if (str->len > 0)
				g_string_append (str, "\n");
			g_string_append_printf (str, "%s\n", as_node_get_data (tmp));

		/* loop on the children */
		} else if (g_strcmp0 (tag, "ul") == 0 ||
			   g_strcmp0 (tag, "ol") == 0) {
			for (tmp_c = tmp->children; tmp_c != NULL; tmp_c = tmp_c->next) {
				tag_c = as_node_get_name (tmp_c);
				if (g_strcmp0 (tag_c, "li") == 0) {
					g_string_append_printf (str,
								" • %s\n",
								as_node_get_data (tmp_c));
				} else {
					/* only <li> is valid in lists */
					g_set_error (error,
						     AS_NODE_ERROR,
						     AS_NODE_ERROR_FAILED,
						     "Tag %s in %s invalid",
						     tag_c, tag);
					return FALSE;
				}
			}
		} else {
			/* only <p>, <ul> and <ol> is valid here */
			g_set_error (error,
				     AS_NODE_ERROR,
				     AS_NODE_ERROR_FAILED,
				     "Unknown tag '%s'", tag);
			return NULL;
		}
	}

	/* success */
	if (str->len > 0)
		g_string_truncate (str, str->len - 1);
	return g_strdup (str->str);
}

/**
 * as_hash_lookup_by_locale:
 * @hash: a #GHashTable.
 * @locale: the locale, or %NULL to use the users default local.
 *
 * Gets the 'best' data entry in a hash table using the user-set list
 * of preferred languages.
 *
 * This is how methods like as_app_get_name(app,NULL) return the localized
 * data for the user.
 *
 * Returns: the string value, or %NULL if there was no data
 *
 * Since: 0.1.0
 **/
const gchar *
as_hash_lookup_by_locale (GHashTable *hash, const gchar *locale)
{
	const gchar *const *locales;
	const gchar *tmp = NULL;
	guint i;

	g_return_val_if_fail (hash != NULL, NULL);

	/* the user specified a locale */
	if (locale != NULL)
		return g_hash_table_lookup (hash, locale);

	/* use LANGUAGE, LC_ALL, LC_MESSAGES and LANG */
	locales = g_get_language_names ();
	for (i = 0; locales[i] != NULL; i++) {
		tmp = g_hash_table_lookup (hash, locales[i]);
		if (tmp != NULL)
			return tmp;
	}
	return NULL;
}

/**
 * as_utils_is_stock_icon_name:
 * @name: an icon name
 *
 * Searches the known list of stock icons.
 *
 * Returns: %TRUE if the icon is a "stock icon name" and does not need to be
 *          included in the AppStream icon tarball
 *
 * Since: 0.1.3
 **/
gboolean
as_utils_is_stock_icon_name (const gchar *name)
{
	_cleanup_free gchar *key = NULL;
	_cleanup_unref_bytes GBytes *data;

	/* load the readonly data section and look for the icon name */
	data = g_resource_lookup_data (as_get_resource (),
				       "/org/freedesktop/appstream-glib/as-stock-icons.txt",
				       G_RESOURCE_LOOKUP_FLAGS_NONE,
				       NULL);
	if (data == NULL)
		return FALSE;
	key = g_strdup_printf ("\n%s\n", name);
	return g_strstr_len (g_bytes_get_data (data, NULL), -1, key) != NULL;
}

/**
 * as_utils_is_spdx_license_id:
 * @license_id: a single SPDX license ID, e.g. "CC-BY-3.0"
 *
 * Searches the known list of SPDX license IDs.
 *
 * Returns: %TRUE if the icon is a valid "SPDX license ID"
 *
 * Since: 0.1.5
 **/
gboolean
as_utils_is_spdx_license_id (const gchar *license_id)
{
	_cleanup_free gchar *key = NULL;
	_cleanup_unref_bytes GBytes *data;

	/* load the readonly data section and look for the icon name */
	data = g_resource_lookup_data (as_get_resource (),
				       "/org/freedesktop/appstream-glib/as-license-ids.txt",
				       G_RESOURCE_LOOKUP_FLAGS_NONE,
				       NULL);
	if (data == NULL)
		return FALSE;
	key = g_strdup_printf ("\n%s\n", license_id);
	return g_strstr_len (g_bytes_get_data (data, NULL), -1, key) != NULL;
}

/**
 * as_utils_spdx_license_tokenize:
 * @license: a license string, e.g. "LGPLv2+ and (QPL or GPLv2) and MIT"
 *
 * Tokenizes the SPDX license string (or any simarly formatted string)
 * into parts. Any non-licence parts of the string e.g. " and " are prefexed
 * with "#".
 *
 * Returns: (transfer full): array of strings
 *
 * Since: 0.1.5
 **/
gchar **
as_utils_spdx_license_tokenize (const gchar *license)
{
	GPtrArray *array;
	gchar buf[1024];
	guint i;
	guint old = 0;
	guint matchlen = 0;

	array = g_ptr_array_new_with_free_func (g_free);
	for (i = 0; license[i] != '\0'; i++) {

		/* leading bracket */
		if (i == 0 && license[i] == '(') {
			matchlen = 1;
			g_snprintf (buf, matchlen + 2, "#%s", &license[i]);
			g_ptr_array_add (array, g_strdup (buf));
			old = i + matchlen;
			continue;
		}

		/* suppport AND and OR's in the license text */
		matchlen = 0;
		if (strncmp (&license[i], " and ", 5) == 0)
			matchlen = 5;
		else if (strncmp (&license[i], " or ", 4) == 0)
			matchlen = 4;

		if (matchlen > 0) {

			/* brackets */
			if (license[i - 1] == ')') {
				i--;
				matchlen++;
			}

			/* get previous token */
			g_snprintf (buf, i - old + 1, "%s", &license[old]);
			g_ptr_array_add (array, g_strdup (buf));

			/* brackets */
			if (license[i + matchlen] == '(')
				matchlen++;

			/* get operation */
			g_snprintf (buf, matchlen + 2, "#%s", &license[i]);
			g_ptr_array_add (array, g_strdup (buf));

			old = i + matchlen;
			i += matchlen - 1;
		}
	}

	/* trailing bracket */
	if (i > 0 && license[i - 1] == ')') {
		/* token */
		g_snprintf (buf, i - old, "%s", &license[old]);
		g_ptr_array_add (array, g_strdup (buf));

		/* brackets */
		g_snprintf (buf, i - 1, "#%s", &license[i - 1]);
		g_ptr_array_add (array, g_strdup (buf));
	} else {
		/* token */
		g_ptr_array_add (array, g_strdup (&license[old]));
	}
	g_ptr_array_add (array, NULL);

	return (gchar **) g_ptr_array_free (array, FALSE);
}

/**
 * as_util_get_possible_kudos:
 *
 * Returns a list of all known kudos, which are metadata values that
 * infer a level of integration or quality.
 *
 * Returns: a static list of possible metadata keys
 *
 * Since: 0.1.4
 **/
const gchar * const *
as_util_get_possible_kudos (void)
{
	static const gchar * const kudos[] = {
		"X-Kudo-SearchProvider",
		"X-Kudo-InstallsUserDocs",
		"X-Kudo-UsesAppMenu",
		"X-Kudo-GTK3",
		"X-Kudo-QT5",
		"X-Kudo-RecentRelease",
		"X-Kudo-UsesNotifications",
		"X-Kudo-Popular",
		NULL };
	return kudos;
}

/**
 * as_utils_check_url_exists:
 * @url: the URL to check.
 * @timeout: the timeout in seconds.
 * @error: A #GError or %NULL
 *
 * Checks to see if a URL is reachable.
 *
 * Returns: %TRUE if the URL was reachable and pointed to a non-zero-length file.
 *
 * Since: 0.1.5
 **/
gboolean
as_utils_check_url_exists (const gchar *url, guint timeout, GError **error)
{
	_cleanup_unref_object SoupMessage *msg = NULL;
	_cleanup_unref_object SoupSession *session = NULL;
	_cleanup_unref_uri SoupURI *base_uri = NULL;

	/* GET file */
	base_uri = soup_uri_new (url);
	if (base_uri == NULL) {
		g_set_error_literal (error,
				     AS_NODE_ERROR,
				     AS_NODE_ERROR_FAILED,
				     "URL not valid");
		return FALSE;
	}
	msg = soup_message_new_from_uri (SOUP_METHOD_GET, base_uri);
	if (msg == NULL) {
		g_set_error_literal (error,
				     AS_NODE_ERROR,
				     AS_NODE_ERROR_FAILED,
				     "Failed to setup message");
		return FALSE;
	}
	session = soup_session_sync_new_with_options (SOUP_SESSION_USER_AGENT,
						      "libappstream-glib",
						      SOUP_SESSION_TIMEOUT,
						      timeout,
						      NULL);
	if (session == NULL) {
		g_set_error_literal (error,
				     AS_NODE_ERROR,
				     AS_NODE_ERROR_FAILED,
				     "Failed to set up networking");
		return FALSE;
	}

	/* send sync */
	if (soup_session_send_message (session, msg) != SOUP_STATUS_OK) {
		g_set_error_literal (error,
				     AS_NODE_ERROR,
				     AS_NODE_ERROR_FAILED,
				     msg->reason_phrase);
		return FALSE;
	}

	/* check if it's a zero sized file */
	if (msg->response_body->length == 0) {
		g_set_error (error,
			     AS_NODE_ERROR,
			     AS_NODE_ERROR_FAILED,
			     "Returned a zero length file");
		return FALSE;
	}
	return TRUE;
}