#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>

#include "logger.h"
#include "pldstr.h"

#include "bytedecoders.h"
#include "olestream-unwrap.h"


struct OLE10_header{
	unsigned char data[6];
	char *attach_name;
	unsigned char data2[8];
	char *fname_1;
	char *fname_2;
	size_t attach_size;
	size_t attach_size_1;
	size_t attach_start_offset;
};


/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_init
 Returns Type	: int
 	----Parameter List
	1. struct OLEUNWRAP_object *oleuw , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_init( struct OLEUNWRAP_object *oleuw )
{
	oleuw->debug = 0;
	oleuw->verbose = 0;
	oleuw->filename_report_fn = NULL;

	return OLEUW_OK;
}

/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_set_debug
 Returns Type	: int
 	----Parameter List
	1. struct OLEUNWRAP_object *oleuw, 
	2.  int level , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_set_debug( struct OLEUNWRAP_object *oleuw, int level )
{
	oleuw->debug = level;
	return OLEUW_OK;
}

/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_set_verbose
 Returns Type	: int
 	----Parameter List
	1. struct OLEUNWRAP_object *oleuw, 
	2.  int level , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_set_verbose( struct OLEUNWRAP_object *oleuw, int level )
{
	oleuw->verbose = level;
	return OLEUW_OK;
}

/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_set_save_unknown_streams
 Returns Type	: int
 	----Parameter List
	1. struct OLEUNWRAP_object *oleuw, 
	2.  int level , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_set_save_unknown_streams( struct OLEUNWRAP_object *oleuw, int level )
{
	oleuw->save_unknown_streams = level;
	return OLEUW_OK;
}


/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_save_stream
 Returns Type	: int
 	----Parameter List
	1. char *fname, 
	2.  char *stream, 
	3.  size_t bytes , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_save_stream( struct OLEUNWRAP_object *oleuw, char *fname, char *decode_path, char *stream, size_t bytes )
{
	char *full_name;
	FILE *f;
	int result = 0;

	full_name = PLD_dprintf("%s/%s", decode_path, fname );
	if (full_name == NULL)
	{
		LOGGER_log("%s:%d:OLEUNWRAP_save_stream:ERROR: Unable to create filename string from '%s' and '%s'",FL,fname,decode_path);
		return -1;
	}

	f = fopen(full_name,"wb");
	if (f != NULL)
	{
		size_t write_count;

		write_count = fwrite( stream, 1, bytes, f );
		if (write_count != bytes)
		{
			LOGGER_log("%s:%d:OLEUNWRAP_save_stream:WARNING: Only wrote %d of %d bytes to file %s\n",FL, write_count, bytes, full_name );
			/* Complaining seems to get us segfaulted*/

		}

		fclose(f);
	} else {
		LOGGER_log("%s:%d:OLEUNWRAP_save_stream:ERROR: Unable to open %s for writing (%s)\n",FL,full_name, strerror(errno));
		result = -1;
	}

	if (full_name) free(full_name);
	return result;
}


/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_decode_attachment
 Returns Type	: int
 	----Parameter List
	1. char *stream , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_decode_attachment( struct OLEUNWRAP_object *oleuw, char *stream, size_t stream_size, char *decode_path )
{
	struct OLE10_header oh;
	char *sp = stream;
	char *data_start_point = stream;
	int result = OLEUW_OK;

	/* Get the data size*/
	oh.attach_size_1 = (size_t)get_4byte_value( sp );
	sp += 4;

	/*	fprintf(stdout,"%s:%d:DEBUG:attachsize = %d, stream length = %d\n", FL, oh.attach_size_1, stream_size );*/

	oh.attach_start_offset = (stream_size -oh.attach_size_1);
	data_start_point = stream +oh.attach_start_offset;

	/*if (oh.attach_start_offset == 4)*/
	if (oh.attach_start_offset < 4)
	{
	  /* If we only had the stream byte-lenght in our header*/
	  /*		then we know we don't have a complex header.*/
		oh.attach_name = PLD_dprintf("unknown-%ld",oh.attach_size_1);
		oh.attach_size = oh.attach_size_1;
	} else {
	  /* Unknown memory segment*/
		memcpy( oh.data, sp, 2 );
		sp += 2;
		
		/* Full attachment string*/
		oh.attach_name = strdup( sp );
		sp = sp + strlen(oh.attach_name) +1;

		/* Attachment full path*/
		oh.fname_1 = strdup( sp );
		sp += strlen(oh.fname_1) +1;

		/* Unknown memory segment*/
		memcpy( oh.data2, sp, 8 );
		sp = sp +8;

		/* Attachment full path*/
		oh.fname_2 = strdup( sp );
		sp += strlen(oh.fname_2) +1;

		oh.attach_size = (size_t)get_4byte_value( sp );
		sp += 4;

		if (oh.attach_size > stream_size) oh.attach_size = stream_size;
	} 

	if (oleuw->debug > 0) LOGGER_log("%s:%d:OLEUNWRAP_decode_attachment:DEBUG: Attachment %s:%s:%s size = %d\n",FL, oh.attach_name, oh.fname_1, oh.fname_2, oh.attach_size );

	result = OLEUNWRAP_save_stream( oleuw, oh.attach_name, decode_path, data_start_point, oh.attach_size );
	if (result == OLEUW_OK)
	{
		if (oleuw->debug > 0) LOGGER_log("%s:%d:OLEUNWRAP_decode_attachment:DEBUG: Calling reporter for the filename",FL);
		if ((oleuw->verbose > 0)&&(oleuw->filename_report_fn != NULL))
		{
			oleuw->filename_report_fn(oh.attach_name);
		}
		/* Do call back to reporting function*/
	}

	/* Clean up our previously allocated data*/
	if (oh.fname_1 != NULL) free(oh.fname_1);
	if (oh.attach_name != NULL) free(oh.attach_name);
	if (oh.fname_2 != NULL) free(oh.fname_2);
	
	return OLEUW_OK;
}

/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_decodestream
 Returns Type	: int
 	----Parameter List
	1. char *element_string, 
	2.  char *stream , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_decodestream( struct OLEUNWRAP_object *oleuw, char *element_string, char *stream, size_t stream_size, char *decode_path )
{
	int result = OLEUW_OK;

	if (strstr(element_string, OLEUW_ELEMENT_10NATIVE_STRING) != NULL) 
	{
		OLEUNWRAP_decode_attachment( oleuw, stream, stream_size, decode_path );

	} else {
		if (oleuw->debug) LOGGER_log("Unable to decode stream with element string '%s'\n", element_string);
		result = OLEUW_STREAM_NOT_DECODED;
	}

	return result;
}


/*-----------------------------------------------------------------\
 Function Name	: OLEUNWRAP_set_filename_report_fn
 Returns Type	: int
 	----Parameter List
	1. struct OLEUNWRAP_object *oleuw, 
	2.  int (*ptr_to_fn)(char *) , 
 	------------------
 Exit Codes	: 
 Side Effects	: 
--------------------------------------------------------------------
 Comments:
 
--------------------------------------------------------------------
 Changes:
 
\------------------------------------------------------------------*/
int OLEUNWRAP_set_filename_report_fn( struct OLEUNWRAP_object *oleuw, int (*ptr_to_fn)(char *) )
{

	oleuw->filename_report_fn = ptr_to_fn;

	return 0;
}

