#include <sys/i2ceeprom.h>
#include <sys/fastfile.h>
#include <sys/errno.h>

struct i2cee_fastfile {
	fastfile_t fastfile;
	
	int32_t		offset,
				size,
				position;
};

int i2cee_ff_seek	(fastfile_t *ff,int position){
	struct i2cee_fastfile *f = (struct i2cee_fastfile*)ff;
	if ((position >= 0) && (position < f->size)){
		f->position = position;
		return ESUCCESS;
	};
	return -ESHORT;
};

int i2cee_ff_tell	(fastfile_t *ff){
	struct i2cee_fastfile *f = (struct i2cee_fastfile*)ff;
	return f->position;
};

int	i2cee_ff_read	(fastfile_t *ff,void *buffer,int len){
	struct i2cee_fastfile *f = (struct i2cee_fastfile*)ff;
	if (!buffer){
		return -ENULLPTR;
	};
	if (f->position + len > f->size){
		len = f->size - f->position;
	};
	len = i2cee_load( f->offset + f->position, buffer, len );
	assert(len);
	
	f->position += len;
	return len;
};

int i2cee_ff_write	(fastfile_t *ff,void *buffer,int len){
	struct i2cee_fastfile *f = (struct i2cee_fastfile*)ff;
	if (!buffer){
		return -ENULLPTR;
	};
	if (f->position + len > f->size){
		len = f->size - f->position;
	};
	len = i2cee_save( f->offset + f->position, buffer, len );
	assert(len);

	f->position += len;
	return len;
};

int i2cee_ff_close	(fastfile_t *ff){
	return ESUCCESS;
};


fastfile_t*	i2cee_define_file(int32_t offset,int32_t size){
	struct i2cee_fastfile *f = (struct i2cee_fastfile*)malloc( sizeof( struct i2cee_fastfile) );
	if (!f){
		return NULL;
	};
	
	memset(f, 0x00, sizeof( *f ) );
	
	f->fastfile.ops.seek = i2cee_ff_seek;
	f->fastfile.ops.tell = i2cee_ff_tell;
	f->fastfile.ops.read = i2cee_ff_read;
	f->fastfile.ops.write = i2cee_ff_write;
	f->fastfile.ops.close = i2cee_ff_close;
	
	return & (f->fastfile);
};