/*

 * @author Hallyson Melo <hallyson.melo@indt.org.br>

 *

 * This program 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 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 Lesser General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#ifdef HAVE_CONFIG_H

#include <config.h>

#endif

#include <string.h>

#include <glib.h>

#include <math.h>

#include <libgnomevfs/gnome-vfs-module.h>

#include <libgnomevfs/gnome-vfs-utils.h>

#include "gmyth_file_transfer.h"

#define GST_MYTHTV_ID_NUM               1

#define MYTHTV_VERSION_DEFAULT          30

#define MYTHTV_BUFFER_SIZE		1024*64

static GnomeVFSResult do_read (GnomeVFSMethod *method,

                               GnomeVFSMethodHandle *method_handle,

                               gpointer buffer,

                               GnomeVFSFileSize num_bytes,

                               GnomeVFSFileSize *bytes_read,

                               GnomeVFSContext *context);

typedef struct {

    GMythFileTransfer *file_transfer;

    gint mythtv_version;

    guint64 content_size;

    guint64 bytes_read;

    guint8 *buffer;

    gsize buffer_offset;

    gsize buffer_remain;

} MythtvHandle;

static GnomeVFSResult

do_open (GnomeVFSMethod *method,

         GnomeVFSMethodHandle **method_handle,

         GnomeVFSURI *uri,

         GnomeVFSOpenMode mode,

         GnomeVFSContext *context)

{

    const gchar *user, *password, *host, *transfer_uri;

    MythtvHandle *myth_handle;

    GString *uri_str;

    guint port;

    gchar *path;

    gboolean ret;

    _GNOME_VFS_METHOD_PARAM_CHECK (method_handle != NULL);

    _GNOME_VFS_METHOD_PARAM_CHECK (uri != NULL);

    g_debug ("[%s] Calling do_open function", __FUNCTION__);

    myth_handle = g_new0 (MythtvHandle, 1);

    if (mode & GNOME_VFS_OPEN_WRITE) {

        return GNOME_VFS_ERROR_NOT_PERMITTED;

    }

    if ((host = gnome_vfs_uri_get_host_name (uri)) == NULL) {

	return GNOME_VFS_ERROR_INVALID_HOST_NAME;

    }

    /* Parse URI */

    path = gnome_vfs_unescape_string (uri->text, NULL);

    port = gnome_vfs_uri_get_host_port (uri);

    user = gnome_vfs_uri_get_user_name (uri);

    password = gnome_vfs_uri_get_password (uri);

    transfer_uri = gnome_vfs_uri_to_string (uri, 

		    GNOME_VFS_URI_HIDE_USER_NAME | GNOME_VFS_URI_HIDE_PASSWORD);

    /* Initialize mythtv handler*/

    myth_handle->file_transfer = NULL;

    myth_handle->mythtv_version = MYTHTV_VERSION_DEFAULT;

    myth_handle->bytes_read = 0;

    myth_handle->content_size = -1;

    /* Connect to the backend */

    myth_handle->file_transfer = gmyth_file_transfer_new ();

    g_return_val_if_fail (myth_handle->file_transfer != NULL, GNOME_VFS_ERROR_NOT_OPEN);

    /* sets the Playback monitor connection */

    uri_str = g_string_new (transfer_uri);

    ret = gmyth_file_transfer_open (myth_handle->file_transfer, uri_str);

    if (ret == FALSE) {

        g_printerr ("Mythtv FileTransfer open error\n");

        return GNOME_VFS_ERROR_NOT_OPEN;

    }

    g_string_free (uri_str, TRUE);

    // TODO: Verify if file exists in the backend

    myth_handle->content_size = myth_handle->file_transfer->filesize;

    myth_handle->buffer = g_malloc0 (MYTHTV_BUFFER_SIZE);

    myth_handle->buffer_offset = 0;

    myth_handle->buffer_remain = 0;

    *method_handle = (GnomeVFSMethodHandle *) myth_handle;

    return GNOME_VFS_OK;

}

static GnomeVFSResult

do_read (GnomeVFSMethod *method,

         GnomeVFSMethodHandle *method_handle,

         gpointer buffer,

         GnomeVFSFileSize num_bytes,

         GnomeVFSFileSize *bytes_read,

         GnomeVFSContext *context)

{

    MythtvHandle *myth_handle = (MythtvHandle *) method_handle;

    GnomeVFSFileSize bytes_to_read;

    g_debug ("do_read(): file size: %llu, already read: %llu, requested: %llu, buffer_offset: %du, buffer_remain: %du", 

		    myth_handle->content_size, myth_handle->bytes_read, num_bytes, 

		    myth_handle->buffer_offset, myth_handle->buffer_remain);

    *bytes_read = 0;

    if (myth_handle->bytes_read >= myth_handle->content_size)

        return GNOME_VFS_ERROR_EOF;

    // fixme: change this to min math function

    if (num_bytes > myth_handle->content_size - myth_handle->bytes_read)

	    bytes_to_read = myth_handle->content_size - myth_handle->bytes_read;

    else

	    bytes_to_read = num_bytes;

    /* Loop sending the Myth File Transfer request:

    * Retry whilst authentication fails and we supply it. */

    if (bytes_to_read > myth_handle->buffer_remain ) {

	guint8 *tmp_buffer = g_malloc0 (MYTHTV_BUFFER_SIZE);

	gint len;

	if (myth_handle->buffer_remain > (MYTHTV_BUFFER_SIZE >> 1)) {

	    // Avoid overlap creating another buffer, in the case the remaining data is bigger than half buffer size

	    tmp_buffer = g_malloc0 (MYTHTV_BUFFER_SIZE);

	    memcpy (tmp_buffer, myth_handle->buffer + myth_handle->buffer_offset, myth_handle->buffer_remain);

	    g_free (myth_handle->buffer);

	    myth_handle->buffer = tmp_buffer;

	} else {

	    memcpy (myth_handle->buffer, myth_handle->buffer + myth_handle->buffer_offset, myth_handle->buffer_remain);

	}

	g_debug ("Reading %d data from backend", MYTHTV_BUFFER_SIZE- myth_handle->buffer_remain);

        len = gmyth_file_transfer_read( myth_handle->file_transfer,

	            myth_handle->buffer + myth_handle->buffer_remain, 

		    MYTHTV_BUFFER_SIZE- myth_handle->buffer_remain, TRUE );

	if (len < 0)

	    return GNOME_VFS_ERROR_IO;

	myth_handle->buffer_offset = 0;

	myth_handle->buffer_remain += len;

    }

    bytes_to_read = (bytes_to_read > myth_handle->buffer_remain) ? myth_handle->buffer_remain : bytes_to_read;

    g_debug ("Returning %du bytes to gnomevfs", (int) bytes_to_read);

    memcpy (buffer, myth_handle->buffer + myth_handle->buffer_offset, bytes_to_read);

    myth_handle->bytes_read += bytes_to_read;

    myth_handle->buffer_offset += bytes_to_read;

    myth_handle->buffer_remain -= bytes_to_read;

    *bytes_read = bytes_to_read;

    return GNOME_VFS_OK;

}

static GnomeVFSResult

do_close (GnomeVFSMethod *method,

          GnomeVFSMethodHandle *method_handle,

          GnomeVFSContext *context)

{

    MythtvHandle *myth_handle = (MythtvHandle *) method_handle;

    if (myth_handle->file_transfer) {

	gmyth_file_transfer_close (myth_handle->file_transfer);

        g_object_unref (myth_handle->file_transfer);

	myth_handle->file_transfer = NULL;

    }

    g_free (myth_handle);

    return GNOME_VFS_OK;

}

static GnomeVFSResult

do_get_file_info (GnomeVFSMethod *method,

                  GnomeVFSURI *uri,

                  GnomeVFSFileInfo *file_info,

                  GnomeVFSFileInfoOptions options,

                  GnomeVFSContext *context)

{

    file_info->name = g_strdup ("fixme.txt");

    file_info->valid_fields = file_info->valid_fields

        | GNOME_VFS_FILE_INFO_FIELDS_TYPE

        | GNOME_VFS_FILE_INFO_FIELDS_MIME_TYPE

        | GNOME_VFS_FILE_INFO_FIELDS_PERMISSIONS;

    file_info->type = GNOME_VFS_FILE_TYPE_REGULAR;

    // fixme: get from file extension?

    file_info->mime_type = g_strdup ("video/x-nuv");

    file_info->permissions =

        GNOME_VFS_PERM_USER_READ |

        GNOME_VFS_PERM_OTHER_READ |

        GNOME_VFS_PERM_GROUP_READ;

    return GNOME_VFS_OK;

}

static gboolean

do_is_local (GnomeVFSMethod *method,

             const GnomeVFSURI *uri)

{

	return FALSE;

}

static GnomeVFSMethod method = {

	sizeof (GnomeVFSMethod),

	do_open,

	NULL,

	do_close,

	do_read,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	do_get_file_info,

	NULL,

	do_is_local,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

	NULL,

};

GnomeVFSMethod *

vfs_module_init (const char *method_name, const char *args)

{

	return &method;

}

void

vfs_module_shutdown (GnomeVFSMethod *method)

{

}