/*

 * Copyright (C) 2007, 2008 OpenedHand Ltd.

 * Copyright (C) 2012 Intel Corporation.

 *

 * Authors: Jorn Baayen <jorn@openedhand.com>

 *          Jens Georg <jensg@openismus.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Library General Public

 * License as published by the Free Software Foundation; either

 * version 2 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

 * Library General Public License for more details.

 *

 * You should have received a copy of the GNU Library 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:gupnp-didl-lite-writer

 * @short_description: DIDL-Lite fragment writer

 *

 * #GUPnPDIDLLiteWriter is a helper class for writing DIDL-Lite fragments.

 */

#include <string.h>

#include "gupnp-didl-lite-writer.h"

#include "gupnp-didl-lite-object.h"

#include "gupnp-didl-lite-object-private.h"

#include "gupnp-didl-lite-descriptor-private.h"

#include "gupnp-didl-lite-writer-private.h"

#include "xml-util.h"

G_DEFINE_TYPE (GUPnPDIDLLiteWriter,

               gupnp_didl_lite_writer,

               G_TYPE_OBJECT);

struct _GUPnPDIDLLiteWriterPrivate {

        xmlNode       *xml_node;

        GUPnPAVXMLDoc *xml_doc;

        xmlNs       *upnp_ns;

        xmlNs       *dc_ns;

        xmlNs       *dlna_ns;

        xmlNs       *pv_ns;

        char        *language;

};

enum {

        PROP_0,

        PROP_XML_NODE,

        PROP_LANGUAGE,

};

static int

compare_prop (const char *a, xmlAttr *attr)

{

        const char *p;

        char *parent_name;

        char *attr_name;

        int ret = -1;

        if (attr->ns != NULL)

                attr_name = g_strjoin (":", attr->ns->prefix, attr->name, NULL);

        else

                attr_name = g_strdup ((const char *) attr->name);

        if (attr->parent->ns != NULL)

                parent_name = g_strjoin (":",

                                         attr->parent->ns->prefix,

                                         attr->parent->name,

                                         NULL);

        else

                parent_name = g_strdup ((const char *) attr->parent->name);

        p = strstr (a, "@");

        if (p)

                if (p == a)

                        /* Top-level property */

                        ret = strcmp (a + 1, attr_name);

                else

                        ret = strncmp (a, parent_name, p - a) ||

                              strcmp (p + 1, attr_name);

        else

                ret = strcmp (a, attr_name);

        g_free (attr_name);

        g_free (parent_name);

        return ret;

}

static gboolean

is_attribute_forbidden (xmlAttr *attr,

                        GList   *allowed)

{

        return g_list_find_custom (allowed,

                                   attr,

                                   (GCompareFunc) compare_prop) == NULL;

}

static int

compare_node_name (const char *a, const char *b)

{

        const char *p;

        int len, result;

        if (a[0] == '@')

                /* Filter is for top-level property */

                return -1;

        p = strstr (a, "@");

        if (p != NULL)

                /* Compare only the string before '@' */

                len = p - a;

        else

                len = strlen (a);

        result = strncmp (a, b, len);

        if (result == 0) {

            /* Avoid that we return a match although only prefixes match like

             * in upnp:album and upnp:albumArtUri, cf. bgo#687462 */

            return strlen (b) - len;

        }

        return result;

}

static gboolean

is_node_forbidden (xmlNode     *node,

                    GList      *allowed,

                    const char *ns)

{

        char *name;

        gboolean ret;

        if (ns != NULL)

                name = g_strjoin (":", ns, node->name, NULL);

        else

                name = g_strdup ((const char *) node->name);

        ret = g_list_find_custom (allowed,

                                  name,

                                  (GCompareFunc) compare_node_name) == NULL;

        g_free (name);

        return ret;

}

static gboolean

is_container_standard_prop (const char *name,

                            const char *namespace,

                            const char *upnp_class)

{

        return g_strcmp0 (upnp_class, "object.container.storageFolder") == 0 &&

               g_strcmp0 (namespace, "upnp") == 0 &&

               strcmp (name, "storageUsed") == 0;

}

static gboolean

is_standard_prop (const char *name,

                  const char *namespace,

                  const char *parent_name)

{

        return strcmp (name, "id") == 0 ||

               strcmp (name, "parentID") == 0 ||

               strcmp (name, "restricted") == 0 ||

               (g_strcmp0 (namespace, "dc") == 0 &&

                strcmp (name, "title") == 0) ||

               (g_strcmp0 (namespace, "upnp") == 0 &&

                strcmp (name, "class") == 0) ||

               (g_strcmp0 (parent_name, "res") == 0 &&

                strcmp (name, "protocolInfo") == 0);

}

static void

filter_attributes (xmlNode             *node,

                   GList               *allowed)

{

        xmlAttr *attr;

        GList   *forbidden = NULL;

        GList   *l;

        /* Find forbidden properties */

        for (attr = node->properties; attr != NULL; attr = attr->next)

                if (!is_standard_prop ((const char *) attr->name,

                                        NULL,

                                        (const char *) attr->parent->name) &&

                    is_attribute_forbidden (attr, allowed))

                        forbidden = g_list_append (forbidden, attr);

        /* Now unset forbidden properties */

        for (l = forbidden; l != NULL; l = l->next)

                xmlRemoveProp ((xmlAttr *) l->data);

        g_list_free (forbidden);

}

static void

filter_node (xmlNode             *node,

             GList               *allowed,

             GUPnPDIDLLiteWriter *writer,

             gboolean             tags_only)

{

        xmlNode *child;

        GList   *forbidden = NULL;

        GList   *l;

        gboolean is_container = FALSE;

        const char *container_class = NULL;

        if (!tags_only)

                filter_attributes (node, allowed);

        if (strcmp ((const char *) node->name, "container") == 0) {

                is_container = TRUE;

                container_class = xml_util_get_child_element_content (node,

                                                                      "class");

        }

        forbidden = NULL;

        for (child = node->children; child != NULL; child = child->next) {

                const char *ns = NULL;

                if (xmlNodeIsText (child))

                        continue;

                if (child->ns != NULL)

                        ns = (const char *) child->ns->prefix;

                if (!(is_container && is_container_standard_prop

                                            ((const char *) child->name,

                                             ns,

                                             container_class)) &&

                    !is_standard_prop ((const char *) child->name,

                                       ns,

                                       (const char *)  node->name) &&

                    is_node_forbidden (child, allowed, ns))

                        forbidden = g_list_append (forbidden, child);

        }

        /* Now remove the forbidden nodes */

        for (l = forbidden; l != NULL; l = l->next) {

                xmlNode *n;

                n = (xmlNode *) l->data;

                xmlUnlinkNode (n);

                xmlFreeNode (n);

        }

        g_list_free (forbidden);

        /* Recurse */

        for (child = node->children; child != NULL; child = child->next)

                if (!xmlNodeIsText (child))

                        filter_node (child, allowed, writer, tags_only);

}

static void

apply_filter (GUPnPDIDLLiteWriter *writer,

              const char          *filter,

              gboolean             tags_only)

{

        char **tokens;

        GList *allowed = NULL;

        unsigned short i;

        xmlNode *node;

        g_return_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer));

        g_return_if_fail (filter != NULL);

        if (filter[0] == '*')

                return;         /* Wildcard */

        tokens = g_strsplit (filter, ",", -1);

        g_return_if_fail (tokens != NULL);

        for (i = 0; tokens[i] != NULL; i++)

                allowed = g_list_append (allowed, tokens[i]);

        for (node = writer->priv->xml_node->children;

             node != NULL;

             node = node->next)

                filter_node (node, allowed, writer, tags_only);

        g_list_free (allowed);

        g_strfreev (tokens);

}

static void

gupnp_didl_lite_writer_init (GUPnPDIDLLiteWriter *writer)

{

        writer->priv = G_TYPE_INSTANCE_GET_PRIVATE (writer,

                                                    GUPNP_TYPE_DIDL_LITE_WRITER,

                                                    GUPnPDIDLLiteWriterPrivate);

}

static void

gupnp_didl_lite_writer_set_property (GObject      *object,

                                     guint         property_id,

                                     const GValue *value,

                                     GParamSpec   *pspec)

{

        GUPnPDIDLLiteWriter *writer;

        writer = GUPNP_DIDL_LITE_WRITER (object);

        switch (property_id) {

        case PROP_LANGUAGE:

                writer->priv->language = g_value_dup_string (value);

                break;

        default:

                G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);

                break;

        }

}

static void

gupnp_didl_lite_writer_get_property (GObject    *object,

                                     guint       property_id,

                                     GValue     *value,

                                     GParamSpec *pspec)

{

        GUPnPDIDLLiteWriter *writer;

        writer = GUPNP_DIDL_LITE_WRITER (object);

        switch (property_id) {

        case PROP_XML_NODE:

                g_value_set_pointer

                        (value, gupnp_didl_lite_writer_get_xml_node (writer));

                break;

        case PROP_LANGUAGE:

                g_value_set_string

                        (value, gupnp_didl_lite_writer_get_language (writer));

                break;

        default:

                G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);

                break;

        }

}

static void

gupnp_didl_lite_writer_constructed (GObject *object)

{

        GObjectClass               *object_class;

        GUPnPDIDLLiteWriterPrivate *priv;

        xmlDoc                     *doc;

        priv = GUPNP_DIDL_LITE_WRITER (object)->priv;

        doc = xmlNewDoc ((unsigned char *) "1.0");

        priv->xml_doc = xml_doc_new (doc);

        priv->xml_node = xmlNewDocNode (priv->xml_doc->doc,

                                        NULL,

                                        (unsigned char *) "DIDL-Lite",

                                        NULL);

        xmlDocSetRootElement (priv->xml_doc->doc, priv->xml_node);

        xml_util_create_namespace (priv->xml_node,

                                   GUPNP_XML_NAMESPACE_DIDL_LITE);

        if (priv->language)

                xmlSetProp (priv->xml_node,

                            (unsigned char *) "lang",

                            (unsigned char *) priv->language);

        object_class = G_OBJECT_CLASS (gupnp_didl_lite_writer_parent_class);

        if (object_class->constructed != NULL)

                object_class->constructed (object);

}

static void

gupnp_didl_lite_writer_dispose (GObject *object)

{

        GObjectClass               *object_class;

        GUPnPDIDLLiteWriterPrivate *priv;

        priv = GUPNP_DIDL_LITE_WRITER (object)->priv;

        g_clear_pointer (&priv->xml_doc, xml_doc_unref);

        object_class = G_OBJECT_CLASS (gupnp_didl_lite_writer_parent_class);

        object_class->dispose (object);

}

static void

gupnp_didl_lite_writer_finalize (GObject *object)

{

        GObjectClass               *object_class;

        GUPnPDIDLLiteWriterPrivate *priv;

        priv = GUPNP_DIDL_LITE_WRITER (object)->priv;

        if (priv->language)

                g_free (priv->language);

        object_class = G_OBJECT_CLASS (gupnp_didl_lite_writer_parent_class);

        object_class->finalize (object);

}

static void

gupnp_didl_lite_writer_class_init (GUPnPDIDLLiteWriterClass *klass)

{

        GObjectClass *object_class;

        object_class = G_OBJECT_CLASS (klass);

        object_class->set_property = gupnp_didl_lite_writer_set_property;

        object_class->get_property = gupnp_didl_lite_writer_get_property;

        object_class->constructed = gupnp_didl_lite_writer_constructed;

        object_class->dispose = gupnp_didl_lite_writer_dispose;

        object_class->finalize = gupnp_didl_lite_writer_finalize;

        g_type_class_add_private (klass, sizeof (GUPnPDIDLLiteWriterPrivate));

        /**

         * GUPnPDIDLLiteWriter:xml-node:

         *

         * The pointer to root node in XML document.

         **/

        g_object_class_install_property

                (object_class,

                 PROP_XML_NODE,

                 g_param_spec_pointer ("xml-node",

                                       "XMLNode",

                                       "The pointer to root node in XML"

                                       " document.",

                                       G_PARAM_READABLE |

                                       G_PARAM_STATIC_NAME |

                                       G_PARAM_STATIC_NICK |

                                       G_PARAM_STATIC_BLURB));

        /**

         * GUPnPDIDLLiteWriter:language:

         *

         * The language the DIDL-Lite fragment is in.

         *

         **/

        g_object_class_install_property

                (object_class,

                 PROP_LANGUAGE,

                 g_param_spec_string ("language",

                                      "Language",

                                      "The language the DIDL-Lite fragment"

                                      " is in.",

                                      NULL,

                                      G_PARAM_CONSTRUCT_ONLY |

                                      G_PARAM_READWRITE |

                                      G_PARAM_STATIC_NAME |

                                      G_PARAM_STATIC_NICK |

                                      G_PARAM_STATIC_BLURB));

}

/**

 * gupnp_didl_lite_writer_new:

 * @language: (allow-none):The language the DIDL-Lite fragment is in, or %NULL

 *

 * Note: @language should always be set to %NULL, DLNA does not support the

 * language parameter.

 *

 * Return value: A new #GUPnPDIDLLiteWriter object.

 **/

GUPnPDIDLLiteWriter *

gupnp_didl_lite_writer_new (const char *language)

{

        return g_object_new (GUPNP_TYPE_DIDL_LITE_WRITER,

                             "language", language,

                             NULL);

}

/**

 * gupnp_didl_lite_writer_add_item:

 * @writer: A #GUPnPDIDLLiteWriter

 *

 * Creates a new item, attaches it to @writer and returns it.

 *

 * Returns: (transfer full): A new #GUPnPDIDLLiteItem object. Unref after usage.

 **/

GUPnPDIDLLiteItem *

gupnp_didl_lite_writer_add_item (GUPnPDIDLLiteWriter *writer)

{

        xmlNode *item_node;

        GUPnPDIDLLiteObject *object;

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        item_node = xmlNewChild (writer->priv->xml_node,

                                NULL,

                                (unsigned char *) "item",

                                NULL);

        object = gupnp_didl_lite_object_new_from_xml (item_node,

                                                      writer->priv->xml_doc,

                                                      writer->priv->upnp_ns,

                                                      writer->priv->dc_ns,

                                                      writer->priv->dlna_ns,

                                                      writer->priv->pv_ns);

        return GUPNP_DIDL_LITE_ITEM (object);

}

/**

 * gupnp_didl_lite_writer_add_container_child_item:

 * @writer: #GUPnPDIDLLiteWriter

 * @container: #GUPnPDIDLLiteContainer

 *

 * Add a child item to a container. This is only useful in DIDL_S playlist

 * creation.

 *

 * Returns: (transfer full): A new #GUPnPDIDLLiteItem object. Unref after

 * usage.

 **/

GUPnPDIDLLiteItem *

gupnp_didl_lite_writer_add_container_child_item

                                        (GUPnPDIDLLiteWriter    *writer,

                                         GUPnPDIDLLiteContainer *container)

{

        xmlNode *item_node, *container_node;

        GUPnPDIDLLiteObject *object;

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_CONTAINER (container), NULL);

        object = GUPNP_DIDL_LITE_OBJECT (container);

        container_node = gupnp_didl_lite_object_get_xml_node (object);

        item_node = xmlNewChild (container_node,

                                 NULL,

                                 (xmlChar *) "item",

                                 NULL);

        object = gupnp_didl_lite_object_new_from_xml (item_node,

                                                      writer->priv->xml_doc,

                                                      writer->priv->upnp_ns,

                                                      writer->priv->dc_ns,

                                                      writer->priv->dlna_ns,

                                                      writer->priv->pv_ns);

        return GUPNP_DIDL_LITE_ITEM (object);

}

/**

 * gupnp_didl_lite_writer_add_container:

 * @writer: A #GUPnPDIDLLiteWriter

 *

 * Creates a new container, attaches it to @writer and returns it.

 *

 * Returns: (transfer full): A new #GUPnPDIDLLiteContainer object. Unref after usage.

 **/

GUPnPDIDLLiteContainer *

gupnp_didl_lite_writer_add_container (GUPnPDIDLLiteWriter *writer)

{

        xmlNode *container_node;

        GUPnPDIDLLiteObject *object;

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        container_node = xmlNewChild (writer->priv->xml_node,

                                      NULL,

                                      (unsigned char *) "container",

                                      NULL);

        object = gupnp_didl_lite_object_new_from_xml (container_node,

                                                      writer->priv->xml_doc,

                                                      writer->priv->upnp_ns,

                                                      writer->priv->dc_ns,

                                                      writer->priv->dlna_ns,

                                                      writer->priv->pv_ns);

        return GUPNP_DIDL_LITE_CONTAINER (object);

}

/**

 * gupnp_didl_lite_writer_add_descriptor:

 * @writer: A #GUPnPDIDLLiteWriter

 *

 * Creates a new descriptor, attaches it to @object and returns it.

 *

 * Returns: (transfer full): A new #GUPnPDIDLLiteDescriptor object. Unref after usage.

 **/

GUPnPDIDLLiteDescriptor *

gupnp_didl_lite_writer_add_descriptor (GUPnPDIDLLiteWriter *writer)

{

        xmlNode *desc_node;

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        desc_node = xmlNewChild (writer->priv->xml_node,

                                 NULL,

                                 (unsigned char *) "desc",

                                 NULL);

        return gupnp_didl_lite_descriptor_new_from_xml (desc_node,

                                                        writer->priv->xml_doc);

}

/**

 * gupnp_didl_lite_writer_get_string:

 * @writer: A #GUPnPDIDLLiteWriter

 *

 * Creates a string representation of the DIDL-Lite XML document.

 *

 * Return value: The DIDL-Lite XML string, or %NULL. #g_free after usage.

 **/

char *

gupnp_didl_lite_writer_get_string (GUPnPDIDLLiteWriter *writer)

{

        xmlBuffer *buffer;

        char      *ret;

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        buffer = xmlBufferCreate ();

        xmlNodeDump (buffer,

                     writer->priv->xml_doc->doc,

                     writer->priv->xml_node,

                     0,

                     0);

        ret = g_strndup ((char *) xmlBufferContent (buffer),

                         xmlBufferLength (buffer));

        xmlBufferFree (buffer);

        return ret;

}

/**

 * gupnp_didl_lite_writer_get_xml_node:

 * @writer: The #GUPnPDIDLLiteWriter

 *

 * Get the pointer to root node in XML document.

 *

 * Returns: (transfer none): The pointer to root node in XML document.

 **/

xmlNode *

gupnp_didl_lite_writer_get_xml_node (GUPnPDIDLLiteWriter *writer)

{

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        return writer->priv->xml_node;

}

/**

 * gupnp_didl_lite_writer_get_language:

 * @writer: #GUPnPDIDLLiteWriter

 *

 * Get the language the DIDL-Lite fragment is in.

 *

 * Returns: (transfer none): The language of the @writer, or %NULL.

 **/

const char *

gupnp_didl_lite_writer_get_language (GUPnPDIDLLiteWriter *writer)

{

        g_return_val_if_fail (GUPNP_IS_DIDL_LITE_WRITER (writer), NULL);

        return writer->priv->language;

}

/**

 * gupnp_didl_lite_writer_filter:

 * @writer: A #GUPnPDIDLLiteWriter

 * @filter: A filter string

 *

 * Clears the DIDL-Lite XML document of the properties not specified in the

 * @filter. The passed filter string would typically come from the 'Filter'

 * argument of Browse or Search actions from a ContentDirectory control point.

 * Please refer to Section 2.3.15 of UPnP AV ContentDirectory version 3

 * specification for details on this string.

 **/

void

gupnp_didl_lite_writer_filter (GUPnPDIDLLiteWriter *writer,

                               const char          *filter)

{

        apply_filter (writer, filter, FALSE);

}

/**

 * gupnp_didl_lite_writer_filter_tags:

 * @writer: A #GUPnPDIDLLiteWriter

 * @filter: A filter string

 *

 * Clears the DIDL-Lite XML document of the properties not specified in the

 * @filter. The passed filter string would typically come from the 'Filter'

 * argument of Browse or Search actions from a ContentDirectory control point.

 * Please refer to Section 2.3.15 of UPnP AV ContentDirectory version 3

 * specification for details on this string.

 *

 * In contrast to gupnp_didl_lite_writer_filter(), this function only removes

 * unwanted tags but leaves all attributes in-place.

 *

 * Return value: None.

 **/

void

gupnp_didl_lite_writer_filter_tags (GUPnPDIDLLiteWriter *writer,

                                    const char          *filter)

{

        apply_filter (writer, filter, TRUE);

}