gnc-html.c

/********************************************************************
 * gnc-html.c -- display HTML with some special gnucash tags.       *
 *                                                                  *
 * Copyright (C) 2000 Bill Gribble <[email protected]>           *
 * Copyright (C) 2001 Linas Vepstas <[email protected]>               *
 *                                                                  *
 * This program is free software; you can redistribute it and/or    *
 * modify it under the terms of the GNU General Public License as   *
 * published by the Free Software Foundation; either version 2 of   *
 * the License, or (at your option) any later version.              *
 *                                                                  *
 * This program 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 General Public License for more details.                     *
 *                                                                  *
 * You should have received a copy of the GNU General Public License*
 * along with this program; if not, contact:                        *
 *                                                                  *
 * Free Software Foundation           Voice:  +1-617-542-5942       *
 * 51 Franklin Street, Fifth Floor    Fax:    +1-617-542-2652       *
 * Boston, MA  02110-1301,  USA       [email protected]                   *
 ********************************************************************/

// libgtkhtml docs:
// http://www.fifi.org/doc/libgtkhtml-dev/html/

#include "config.h"

#include <gtk/gtk.h>
#include <glib/gi18n.h>
#include <glib/gstdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <regex.h>

#include "Account.h"
#include "print-session.h"
#include "gnc-engine.h"
#include "gnc-html.h"
#include "gnc-html-history.h"

/* indicates the debugging module that this .o belongs to.  */
static QofLogModule log_module = GNC_MOD_HTML;

/* hashes for URLType -> protocol and protocol -> URLType */
static GHashTable * gnc_html_type_to_proto_hash = NULL;
GHashTable * gnc_html_proto_to_type_hash = NULL;

/* hashes an HTML <object classid="ID"> classid to a handler function */
GHashTable* gnc_html_object_handlers = NULL;

/* hashes handlers for loading different URLType data */
GHashTable* gnc_html_stream_handlers = NULL;

/* hashes handlers for handling different URLType data */
GHashTable* gnc_html_url_handlers = NULL;

/* hashes an HTML <object classid="ID"> classid to a handler function */
extern GHashTable* gnc_html_object_handlers;

G_DEFINE_ABSTRACT_TYPE(GncHtml, gnc_html, GTK_TYPE_BIN)

static void gnc_html_class_init( GncHtmlClass* klass );
static void gnc_html_dispose( GObject* obj );
static void gnc_html_finalize( GObject* obj );

//#define GNC_HTML_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE((o), GNC_TYPE_HTML, GncHtmlPrivate))
#define GNC_HTML_GET_PRIVATE(o) (GNC_HTML(o)->priv)

#include "gnc-html-p.h"

static void
gnc_html_class_init( GncHtmlClass* klass )
{
    GObjectClass *gobject_class = G_OBJECT_CLASS(klass);

    gobject_class->dispose = gnc_html_dispose;
    gobject_class->finalize = gnc_html_finalize;

    klass->show_url = NULL;
    klass->show_data = NULL;
    klass->reload = NULL;
    klass->copy_to_clipboard = NULL;
    klass->export_to_file = NULL;
    klass->print = NULL;
    klass->cancel = NULL;
    klass->parse_url = NULL;
    klass->set_parent = NULL;
}

static void
gnc_html_init( GncHtml* self )
{
    GncHtmlPrivate* priv;
    priv = self->priv = g_new0( GncHtmlPrivate, 1 );

    priv->container = gtk_scrolled_window_new( NULL, NULL );
    gtk_scrolled_window_set_policy( GTK_SCROLLED_WINDOW(priv->container),
                                    GTK_POLICY_AUTOMATIC,
                                    GTK_POLICY_AUTOMATIC );
    priv->request_info = g_hash_table_new( g_str_hash, g_str_equal );
    priv->history = gnc_html_history_new();
}

static void
gnc_html_dispose( GObject* obj )
{
    GncHtml* self = GNC_HTML(obj);
    GncHtmlPrivate* priv = GNC_HTML_GET_PRIVATE(self);

    if ( priv->container != NULL )
    {
        gtk_widget_destroy( GTK_WIDGET(priv->container) );
        g_object_unref( G_OBJECT(priv->container) );
        priv->container = NULL;
    }
    if ( priv->request_info != NULL )
    {
        g_hash_table_destroy( priv->request_info );
        priv->request_info = NULL;
    }
    if ( priv->history != NULL )
    {
        gnc_html_history_destroy( priv->history );
        priv->history = NULL;
    }

    G_OBJECT_CLASS(gnc_html_parent_class)->dispose( obj );
}

static void
gnc_html_finalize( GObject* obj )
{
    GncHtml* self = GNC_HTML(obj);

    if ( self->priv != NULL )
    {
        g_free( self->priv );
        self->priv = NULL;
    }

    G_OBJECT_CLASS(gnc_html_parent_class)->finalize( obj );
}

/***********************************************************************************/

static char*
extract_machine_name( const gchar* path )
{
    gchar machine_rexp[] = "^(//[^/]*)/*(.*)?$";
    regex_t compiled_m;
    regmatch_t match[4];
    gchar* machine = NULL;

    if ( path == NULL ) return NULL;

    regcomp( &compiled_m, machine_rexp, REG_EXTENDED );

    /* step 1: split the machine name away from the path
     * components */
    if ( !regexec( &compiled_m, path, 4, match, 0 ) )
    {
        /* $1 is the machine name */
        if ( match[1].rm_so != -1 )
        {
            machine = g_strndup( path + match[1].rm_so, match[1].rm_eo - match[1].rm_so );
        }
    }
    regfree(&compiled_m);
    return machine;
}

/********************************************************************
 * gnc_html_parse_url
 * this takes a URL and determines the protocol type, location, and
 * possible anchor name from the URL.
 ********************************************************************/

URLType
gnc_html_parse_url( GncHtml* self, const gchar* url,
                    gchar** url_location, gchar** url_label )
{
    gchar uri_rexp[] = "^(([^:][^:]+):)?([^#]+)?(#(.*))?$";
    regex_t compiled;
    regmatch_t match[6];
    gchar* protocol = NULL;
    gchar* path = NULL;
    gchar* label = NULL;
    gboolean found_protocol = FALSE;
    gboolean found_path = FALSE;
    gboolean found_label = FALSE;
    URLType retval;
    GncHtmlPrivate* priv = GNC_HTML_GET_PRIVATE(self);

    g_return_val_if_fail( self != NULL, NULL );
    g_return_val_if_fail( GNC_IS_HTML(self), NULL );

    DEBUG( "parsing %s, base_location %s",
           url ? url : "(null)",
           self ? (priv->base_location ? priv->base_location
                   : "(null base_location)")
               : "(null html)");

    regcomp( &compiled, uri_rexp, REG_EXTENDED );

    if ( !regexec( &compiled, url, 6, match, 0 ) )
    {
        if ( match[2].rm_so != -1 )
        {
            protocol = g_new0( gchar, match[2].rm_eo - match[2].rm_so + 1 );
            strncpy( protocol, url + match[2].rm_so, match[2].rm_eo - match[2].rm_so );
            protocol[match[2].rm_eo - match[2].rm_so] = 0;
            found_protocol = TRUE;
        }
        if ( match[3].rm_so != -1 )
        {
            path = g_new0( gchar, match[3].rm_eo - match[3].rm_so + 1 );
            strncpy( path, url + match[3].rm_so, match[3].rm_eo - match[3].rm_so );
            path[match[3].rm_eo - match[3].rm_so] = 0;
            found_path = TRUE;
        }
        if ( match[5].rm_so != -1 )
        {
            label = g_new0( gchar, match[5].rm_eo - match[5].rm_so + 1 );
            strncpy( label, url + match[5].rm_so, match[5].rm_eo - match[5].rm_so );
            label[match[5].rm_eo - match[5].rm_so] = 0;
            found_label = TRUE;
        }
    }

    regfree( &compiled );

    if ( found_protocol )
    {
        retval = g_hash_table_lookup( gnc_html_proto_to_type_hash, protocol );
        if ( retval == NULL )
        {
            PWARN( "unhandled URL type for '%s'", url ? url : "(null)" );
            retval = URL_TYPE_OTHER;
        }
    }
    else if ( found_label && !found_path )
    {
        retval = URL_TYPE_JUMP;
    }
    else
    {
        if ( self )
        {
            retval = priv->base_type;
        }
        else
        {
            retval = URL_TYPE_FILE;
        }
    }

    g_free( protocol );

    if ( !g_strcmp0( retval, URL_TYPE_FILE ) )
    {
        if ( !found_protocol && path && self && priv->base_location )
        {
            if ( g_path_is_absolute( path ) )
            {
                *url_location = g_strdup( path );
            }
            else
            {
                *url_location = g_build_filename( priv->base_location, path, (gchar*)NULL );
            }
            g_free( path );
        }
        else
        {
            *url_location = g_strdup( path );
            g_free( path );
        }

    }
    else if ( !g_strcmp0( retval, URL_TYPE_JUMP ) )
    {
        *url_location = NULL;
        g_free( path );

    }
    else
    {
        /* case URL_TYPE_OTHER: */

        if ( !found_protocol && path && self && priv->base_location )
        {
            if ( g_path_is_absolute( path ) )
            {
                *url_location = g_build_filename( extract_machine_name( priv->base_location ),
                                                  path, (gchar*)NULL );
            }
            else
            {
                *url_location = g_build_filename( priv->base_location, path, (gchar*)NULL );
            }
            g_free( path );
        }
        else
        {
            *url_location = g_strdup( path );
            g_free( path );
        }
    }

    *url_label = label;
    return retval;
}

/********************************************************************
 * gnc_html_show_data
 * display some HTML that the creator of the gnc-html got from
 * somewhere.
 ********************************************************************/

void
gnc_html_show_data( GncHtml* self, const gchar* data, int datalen )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->show_data != NULL )
    {
        GNC_HTML_GET_CLASS(self)->show_data( self, data, datalen );
    }
    else
    {
        DEBUG( "'show_data' not implemented" );
    }
}


/********************************************************************
 * gnc_html_show_url
 *
 * open a URL.  This is called when the user clicks a link or
 * for the creator of the gnc_html window to explicitly request
 * a URL.
 ********************************************************************/

void
gnc_html_show_url( GncHtml* self, URLType type,
                   const gchar* location, const gchar* label,
                   gboolean new_window_hint )
{
    URLType lc_type = NULL;

    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    lc_type = g_ascii_strdown (type, -1);
    if ( GNC_HTML_GET_CLASS(self)->show_url != NULL )
    {
        GNC_HTML_GET_CLASS(self)->show_url( self, lc_type, location, label, new_window_hint );
    }
    else
    {
        DEBUG( "'show_url' not implemented" );
    }

    g_free (lc_type);
}


/********************************************************************
 * gnc_html_reload
 * reload the current page
 ********************************************************************/

void
gnc_html_reload( GncHtml* self )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->reload != NULL )
    {
        GNC_HTML_GET_CLASS(self)->reload( self );
    }
    else
    {
        DEBUG( "'reload' not implemented" );
    }
}

/********************************************************************
 * gnc_html_cancel
 * cancel any outstanding HTML fetch requests.
 ********************************************************************/

void
gnc_html_cancel( GncHtml* self )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->cancel != NULL )
    {
        GNC_HTML_GET_CLASS(self)->cancel( self );
    }
    else
    {
        DEBUG( "'cancel' not implemented" );
    }
}


/********************************************************************
 * gnc_html_destroy
 * destroy the struct
 ********************************************************************/

void
gnc_html_destroy( GncHtml* self )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( g_object_is_floating( G_OBJECT(self) ) )
    {
        (void)g_object_ref_sink( G_OBJECT(self) );
    }

    g_object_unref( G_OBJECT(self) );
}

void
gnc_html_set_urltype_cb( GncHtml* self, GncHTMLUrltypeCB urltype_cb )
{
    GncHtmlPrivate* priv;

    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    priv = GNC_HTML_GET_PRIVATE(self);
    priv->urltype_cb = urltype_cb;
}

void
gnc_html_set_load_cb( GncHtml* self, GncHTMLLoadCB load_cb, gpointer data )
{
    GncHtmlPrivate* priv;

    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    priv = GNC_HTML_GET_PRIVATE(self);
    priv->load_cb = load_cb;
    priv->load_cb_data = data;
}

void
gnc_html_set_flyover_cb( GncHtml* self, GncHTMLFlyoverCB flyover_cb, gpointer data )
{
    GncHtmlPrivate* priv;

    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    priv = GNC_HTML_GET_PRIVATE(self);
    priv->flyover_cb = flyover_cb;
    priv->flyover_cb_data = data;
}

void
gnc_html_set_button_cb( GncHtml* self, GncHTMLButtonCB button_cb, gpointer data )
{
    GncHtmlPrivate* priv;

    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    priv = GNC_HTML_GET_PRIVATE(self);
    priv->button_cb = button_cb;
    priv->button_cb_data = data;
}

void
gnc_html_copy_to_clipboard( GncHtml* self )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->copy_to_clipboard != NULL )
    {
        GNC_HTML_GET_CLASS(self)->copy_to_clipboard( self );
    }
    else
    {
        DEBUG( "'copy_to_clipboard' not implemented" );
    }
}

/**************************************************************
 * gnc_html_export_to_file : wrapper around the builtin function in gtkhtml
 **************************************************************/

gboolean
gnc_html_export_to_file( GncHtml* self, const gchar* filepath )
{
    g_return_val_if_fail( self != NULL, FALSE );
    g_return_val_if_fail( GNC_IS_HTML(self), FALSE );

    if ( GNC_HTML_GET_CLASS(self)->export_to_file != NULL )
    {
        return GNC_HTML_GET_CLASS(self)->export_to_file( self, filepath );
    }
    else
    {
        DEBUG( "'export_to_file' not implemented" );
        return FALSE;
    }
}

void
gnc_html_print( GncHtml* self, const gchar* jobname, gboolean export_pdf )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->print != NULL )
    {
        GNC_HTML_GET_CLASS(self)->print( self, jobname, export_pdf );
    }
    else
    {
        DEBUG( "'print' not implemented" );
    }
}

gnc_html_history *
gnc_html_get_history( GncHtml* self )
{
    g_return_val_if_fail( self != NULL, NULL );
    g_return_val_if_fail( GNC_IS_HTML(self), NULL );

    return GNC_HTML_GET_PRIVATE(self)->history;
}


GtkWidget *
gnc_html_get_widget( GncHtml* self )
{
    g_return_val_if_fail( self != NULL, NULL );
    g_return_val_if_fail( GNC_IS_HTML(self), NULL );

    return GNC_HTML_GET_PRIVATE(self)->container;
}

void
gnc_html_set_parent( GncHtml* self, GtkWindow* parent )
{
    g_return_if_fail( self != NULL );
    g_return_if_fail( GNC_IS_HTML(self) );

    if ( GNC_HTML_GET_CLASS(self)->set_parent != NULL )
    {
        GNC_HTML_GET_CLASS(self)->set_parent( self, parent );
    }
    else
    {
        DEBUG( "'set_parent' not implemented" );
    }
}

/* Register the URLType if it doesn't already exist.
 * Returns TRUE if successful, FALSE if the type already exists.
 */
gboolean
gnc_html_register_urltype( URLType type, const char *protocol )
{
    URLType  lc_type  = NULL;
    char    *lc_proto = NULL;

    if (!gnc_html_type_to_proto_hash)
    {
        gnc_html_type_to_proto_hash = g_hash_table_new (g_str_hash, g_str_equal);
        gnc_html_proto_to_type_hash = g_hash_table_new (g_str_hash, g_str_equal);
    }
    if (!protocol) return FALSE;

    lc_type = g_ascii_strdown (type, -1);
    if (g_hash_table_lookup (gnc_html_type_to_proto_hash, lc_type))
    {
        g_free (lc_type);
        return FALSE;
    }

    lc_proto = g_ascii_strdown (protocol, -1);
    g_hash_table_insert (gnc_html_type_to_proto_hash, lc_type, (gpointer)lc_proto);
    if (*lc_proto)
        g_hash_table_insert (gnc_html_proto_to_type_hash, (gpointer)lc_proto, lc_type);

    return TRUE;
}

void
gnc_html_initialize( void )
{
    int i;
    static struct
    {
        URLType type;
        char *  protocol;
    } types[] =
    {
        { URL_TYPE_FILE, "file" },
        { URL_TYPE_JUMP, "" },
        { URL_TYPE_HTTP, "http" },
        { URL_TYPE_FTP, "ftp" },
        { URL_TYPE_SECURE, "https" },
        { URL_TYPE_REGISTER, "gnc-register" },
        { URL_TYPE_ACCTTREE, "gnc-acct-tree" },
        { URL_TYPE_REPORT, "gnc-report" },
        { URL_TYPE_OPTIONS, "gnc-options" },
        { URL_TYPE_SCHEME, "gnc-scm" },
        { URL_TYPE_HELP, "gnc-help" },
        { URL_TYPE_XMLDATA, "gnc-xml" },
        { URL_TYPE_PRICE, "gnc-price" },
        { URL_TYPE_BUDGET, "gnc-budget" },
        { URL_TYPE_OTHER, "" },
        { NULL, NULL }
    };

    for (i = 0; types[i].type; i++)
        gnc_html_register_urltype (types[i].type, types[i].protocol);
}

gchar*
gnc_build_url( URLType type, const gchar* location, const gchar* label )
{
    URLType  lc_type  = NULL;
    char * type_name;

    DEBUG(" ");
    lc_type = g_ascii_strdown (type, -1);
    type_name = g_hash_table_lookup (gnc_html_type_to_proto_hash, lc_type);
    g_free (lc_type);
    if (!type_name)
        type_name = "";

    if (label)
    {
        return g_strdup_printf("%s%s%s#%s", type_name, (*type_name ? ":" : ""),
                               (location ? location : ""),
                               label ? label : "");
    }
    else
    {
        return g_strdup_printf("%s%s%s", type_name, (*type_name ? ":" : ""),
                               (location ? location : ""));
    }
}

/********************************************************************
 * gnc_html_encode_string
 * RFC 1738 encoding of string for submission with an HTML form.
 * GPL code lifted from gtkhtml.  copyright notice:
 *
 * Copyright (C) 1997 Martin Jones ([email protected])
 * Copyright (C) 1997 Torben Weis ([email protected])
 * Copyright (C) 1999 Helix Code, Inc.
 ********************************************************************/

char *
gnc_html_encode_string(const char * str)
{
    static gchar *safe = "$-._!*(),"; /* RFC 1738 */
    unsigned pos      = 0;
    GString *encoded  = g_string_new ("");
    gchar buffer[5], *ptr;
    guchar c;

    if (!str) return NULL;

    while (pos < strlen(str))
    {
        c = (unsigned char) str[pos];

        if ((( c >= 'A') && ( c <= 'Z')) ||
                (( c >= 'a') && ( c <= 'z')) ||
                (( c >= '0') && ( c <= '9')) ||
                (strchr(safe, c)))
        {
            encoded = g_string_append_c (encoded, c);
        }
        else if ( c == ' ' )
        {
            encoded = g_string_append_c (encoded, '+');
        }
        else if ( c == '\n' )
        {
            encoded = g_string_append (encoded, "%0D%0A");
        }
        else if ( c != '\r' )
        {
            sprintf( buffer, "%%%02X", (int)c );
            encoded = g_string_append (encoded, buffer);
        }
        pos++;
    }

    ptr = encoded->str;

    g_string_free (encoded, FALSE);

    return (char *)ptr;
}


char *
gnc_html_decode_string(const char * str)
{
    static gchar * safe = "$-._!*(),"; /* RFC 1738 */
    GString * decoded  = g_string_new ("");
    const gchar   * ptr;
    guchar  c;
    guint   hexval;
    ptr = str;

    if (!str) return NULL;

    while (*ptr)
    {
        c = (unsigned char) * ptr;
        if ((( c >= 'A') && ( c <= 'Z')) ||
                (( c >= 'a') && ( c <= 'z')) ||
                (( c >= '0') && ( c <= '9')) ||
                (strchr(safe, c)))
        {
            decoded = g_string_append_c (decoded, c);
        }
        else if ( c == '+' )
        {
            decoded = g_string_append_c (decoded, ' ');
        }
        else if (!strncmp(ptr, "%0D0A", 5))
        {
            decoded = g_string_append (decoded, "\n");
            ptr += 4;
        }
        else if (c == '%')
        {
            ptr++;
            if (1 == sscanf(ptr, "%02X", &hexval))
                decoded = g_string_append_c(decoded, (char)hexval);
            else
                decoded = g_string_append_c(decoded, ' ');
            ptr++;
        }
        ptr++;
    }
    ptr = decoded->str;
    g_string_free (decoded, FALSE);

    return (char *)ptr;
}

/********************************************************************
 * escape/unescape_newlines : very simple string encoding for GPG
 * ASCII-armored text.
 ********************************************************************/

char *
gnc_html_unescape_newlines(const gchar * in)
{
    const char * ip = in;
    char    * cstr = NULL;
    GString * rv = g_string_new("");

    for (ip = in; *ip; ip++)
    {
        if ((*ip == '\\') && (*(ip + 1) == 'n'))
        {
            g_string_append(rv, "\n");
            ip++;
        }
        else
        {
            g_string_append_c(rv, *ip);
        }
    }

    g_string_append_c(rv, 0);
    cstr = rv->str;
    g_string_free(rv, FALSE);
    return cstr;
}

char *
gnc_html_escape_newlines(const gchar * in)
{
    char *out;
    const char * ip   = in;
    GString * escaped = g_string_new("");

    for (ip = in; *ip; ip++)
    {
        if (*ip == '\012')
        {
            g_string_append(escaped, "\\n");
        }
        else
        {
            g_string_append_c(escaped, *ip);
        }
    }
    g_string_append_c(escaped, 0);
    out = escaped->str;
    g_string_free(escaped, FALSE);
    return out;
}

void
gnc_html_register_object_handler( const char * classid,
                                  GncHTMLObjectCB hand )
{
    g_return_if_fail( classid != NULL );

    if ( gnc_html_object_handlers == NULL )
    {
        gnc_html_object_handlers = g_hash_table_new( g_str_hash, g_str_equal );
    }

    gnc_html_unregister_object_handler( classid );
    if ( hand != NULL )
    {
        gchar *lc_id  = g_ascii_strdown (classid, -1);
        g_hash_table_insert( gnc_html_object_handlers, lc_id, hand );
    }
}

void
gnc_html_unregister_object_handler( const gchar* classid )
{
    gchar* keyptr = NULL;
    gchar* valptr = NULL;
    gchar** p_keyptr = &keyptr;
    gchar** p_valptr = &valptr;
    gchar* lc_id = g_ascii_strdown (classid, -1);

    if ( g_hash_table_lookup_extended( gnc_html_object_handlers,
                                       lc_id,
                                       (gpointer *)p_keyptr,
                                       (gpointer *)p_valptr) )
    {
        g_hash_table_remove( gnc_html_object_handlers, lc_id );
        g_free( keyptr );
    }
    g_free( lc_id );
}

void
gnc_html_register_stream_handler( URLType url_type, GncHTMLStreamCB hand )
{
    g_return_if_fail( url_type != NULL && *url_type != '\0' );

    if ( gnc_html_stream_handlers == NULL )
    {
        gnc_html_stream_handlers = g_hash_table_new( g_str_hash, g_str_equal );
    }

    gnc_html_unregister_stream_handler( url_type );
    if ( hand != NULL )
    {
        URLType  lc_type  = g_ascii_strdown (url_type, -1);
        g_hash_table_insert( gnc_html_stream_handlers, lc_type, hand );
    }
}

void
gnc_html_unregister_stream_handler( URLType url_type )
{
    URLType  lc_type = g_ascii_strdown (url_type, -1);
    g_hash_table_remove( gnc_html_stream_handlers, lc_type );
    g_free(lc_type);
}

void
gnc_html_register_url_handler( URLType url_type, GncHTMLUrlCB hand )
{
    g_return_if_fail( url_type != NULL && *url_type != '\0' );

    if ( gnc_html_url_handlers == NULL )
    {
        gnc_html_url_handlers = g_hash_table_new( g_str_hash, g_str_equal );
    }

    gnc_html_unregister_url_handler( url_type );
    if ( hand != NULL )
    {
        URLType lc_type = g_ascii_strdown (url_type, -1);
        g_hash_table_insert( gnc_html_url_handlers, lc_type, hand );
    }
}

void
gnc_html_unregister_url_handler( URLType url_type )
{
    URLType lc_type = g_ascii_strdown (url_type, -1);
    g_hash_table_remove( gnc_html_url_handlers, lc_type );
    g_free(lc_type);
}