/*
   logger.c
   Copyright (C) 2003 Antoine Drouin

  This file is part of paparazzi.

  paparazzi 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, or (at your option)
  any later version.

  paparazzi 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 paparazzi; see the file COPYING.  If not, write to
  the Free Software Foundation, 59 Temple Place - Suite 330,
  Boston, MA 02111-1307, USA.
*/


#include <sys/types.h>
#include <dirent.h>
#include <libgen.h>
#include <string.h>
#include <stdio.h>
#include <errno.h>
#include <sys/stat.h>
#include <glib.h>

#include "logger.h"

//static GList* logger_parse_messages(struct PprzProtocol* protocol, xmlDocPtr doc, xmlNodePtr cur);
static GList *logger_parse_message( struct PprzProtocol *protocol, GList *msgs,
                                    const guchar *buf );

struct Logger *logger_new( const gchar *out_file, xmlDocPtr doc )
{
  const gchar *opening = "<data>\n";
  struct Logger *this = g_new( struct Logger, 1 );
  if ( this ) {
    GError *err = NULL;

    gchar *copy = strdup( out_file );
    gchar *out_dir = dirname( copy );
    DIR *d;
    if ( !( d = opendir( out_dir ) ) ) {
      if  ( errno == ENOENT ) {
        if ( mkdir( out_dir, S_IRWXU | S_IRWXG ) ) {
          g_message( "log directory %s doesn't exist and could not create it", out_dir );
          /* FIXME : FREE */
          return NULL;
        }
      } else {
        g_message( "could not acces log directory %s %s", out_dir,
                   g_strerror( errno ) );
        /* FIXME : FREE */
        return NULL;
      }
    }
    closedir( d );
    g_free( copy );

    xmlSaveFormatFile ( out_file, doc, 1 );
    /* FIXME : check result */

    this->channel = g_io_channel_new_file( out_file, "a", &err );
    if ( err ) {
      g_message( "could not open log file %s : %s", out_file, err->message );
      g_error_free( err );
      g_free( this );
      return NULL;
    }
    g_io_channel_write_chars( this->channel, opening, strlen( opening ), NULL,
                              NULL );
  }
  return this;

}


void logger_free( struct Logger *this )
{
  const gchar *closing = "</data>\n</log>\n";
  g_io_channel_write_chars( this->channel, closing, strlen( closing ), NULL,
                            NULL );
  g_io_channel_flush( this->channel, NULL );
  //  g_io_channel_free(this->channel);
  g_free( this );
}

void logger_log( struct Logger *this, struct PprzMsg *msg )
{
  GString *str;
  pprz_protocol_ascii_of_msg( msg, &str );
  if ( str ) {
    GError *err = NULL;
    guint len;
    g_io_channel_write_chars ( this->channel, str->str, str->len, &len, &err );
    if ( err ) {
      g_warning( "log write failed %s", err->message );
      g_error_free( err );
      g_string_free( str, TRUE );
      return;
    }
    g_string_free( str, TRUE );
    g_io_channel_flush( this->channel, &err );
    if ( err ) {
      g_warning( "log flush failed %s", err->message );
      g_error_free( err );
      return;
    }
  }
}


GList  *logger_parse_log( const gchar *filename,
                          struct PprzProtocol **protocol )
{
  xmlDocPtr doc;
  xmlNodePtr cur;

  GList *msgs = NULL;
  const gchar *protocol_closure = "</protocol>";
  gchar *contents, *data_start;
  gsize len;
  GError *err;
  gboolean res = g_file_get_contents( filename, &contents, &len, &err );

  if ( !res ) {
    g_message( "could not read file %s : %s", filename, err->message );
    g_error_free( err );
    return NULL;
  }

  if ( !( data_start = g_strstr_len( contents, len, protocol_closure ) ) ) {
    g_free( contents );
    g_message( "protocol closing not found" );
    return NULL;
  }

  data_start += strlen( protocol_closure );

  if ( !( doc = xmlParseMemory( contents, data_start - contents ) ) ) {
    g_free( contents );
    g_message( "error parsing protocol xml" );
    return NULL;
  }

  if ( !( cur = xmlDocGetRootElement( doc ) ) ) {
    g_free( contents );
    g_message( "empty protocol" );
    return NULL;
  }

  if ( !( *protocol = pprz_protocol_new_from_xml( doc, cur ) ) ) {
    g_free( contents );
    g_message( "error interpreting protocol" );
    return NULL;
  }

  msgs = logger_parse_message( *protocol, msgs, data_start );
  g_free( contents );

  return msgs;
}

/* static GList* logger_parse_messages(struct PprzProtocol* protocol, xmlDocPtr doc, xmlNodePtr cur) { */

/* if (!cur) return NULL;                                   */
/*   if (xmlStrcmp(cur->name, (const xmlChar *) "data"))    */
/*     return cur->next?logger_parse_messages(protocol, doc, cur->next):NULL; */
/*   cur = cur->xmlChildrenNode; */

/*   if (xmlStrcmp(cur->name, (const xmlChar *) "text"))    */
/*     return NULL; */

/*   return logger_parse_message(protocol, NULL, cur->content); */
/* } */

static GList *logger_parse_message( struct PprzProtocol *protocol, GList *msgs,
                                    const guchar *buf )
{
  guchar *next;
  struct PprzMsg *msg =  pprz_protocol_msg_new_of_ascii( protocol, buf );
  if ( msg )
    msgs = g_list_append( msgs, msg );
  if ( ( next = index( buf, '\n' ) ) )
    return logger_parse_message( protocol, msgs, next + 1 );
  return msgs;
}