#ifndef __VHEX_HYPERVISOR__
# define __VHEX_HYPERVISOR__

#include <stddef.h>
#include <stdint.h>

/* declare driver structure */
#include <vhex/driver.h>

/* real Vhex world with driver bitmap and meta information for the hypervisor */
struct vhex_world {
	/* world driver information */
	struct {
		struct vhex_driver *context;
		int flags;
	} *driver;

	/* internal information used by the hypervisor */
	char const * name;
	uint8_t status;
};

/* define world status states */
#define HYP_WORLD_STATUS_STATE_UNUSED		(1 << 0)
#define HYP_WORLD_STATUS_STATE_UNINIT		(1 << 1)
#define HYP_WORLD_STATUS_STATE_USED		(1 << 2)

/* define world status flags */
#define HYP_WORLD_STATUS_FLAG_UNDELETABLE	(1 << 0)

/* hypervisor world status helper */

#define HYP_WORLD_STATUS_SET(flags,state) \
	(((flags & 0x0f) << 4) | ((state & 0x0f) << 0))

#define HYP_WORLD_STATUS_SET_STATE(status, state)	\
	do {					\
		status &= 0x0f;				\
		status |= (state & 0x0f) << 0;		\
	} while (0);

#define HYP_WORLD_STATUS_SET_FLAGS(status, flags)	\
	do {					\
		status &= 0xf0;				\
		status |= (state & 0x0f) << 4;		\
	} while (0);

/* hypervisor world status getter */

#define HYP_WORLD_STATUS_FLAGS(status)		((status & 0xf0) >> 4)
#define HYP_WORLD_STATUS_STATE(status)		((status & 0x0f) >> 0)


/* hypervisor driver status */
enum {
	HYP_WORLD_DRV_UNUSED	= VHEX_DRV_UNUSED,
	HYP_WORLD_DRV_USED	= VHEX_DRV_USED,
};

/* hyp_word_t : hypervisor world ID */
typedef int hyp_world_t;

//---
// User-level API
//---

/* possible returned value */
enum {
	hyp_world_already_exists	= -1,
	hyp_world_not_found		= -2,
	hyp_world_bad_id		= -3,
	hyp_world_currently_in_use	= -4,
	hyp_world_undeletable		= -5,
};

/* hypervisor_world_new() : create a new world with its name */
extern hyp_world_t hypervisor_world_new(
	char const * const restrict name,
	int flags
);

/* hypervisor_world_find() : find a world ID using its name */
extern hyp_world_t hypervisor_world_find(char const * const restrict name);

/* hypervisor_world_get() : get a word using its ID */
extern struct vhex_world *hypervisor_world_get(hyp_world_t id);

/* hypervisor_world_switch() : perform a world switch */
extern int hypervisor_world_switch(hyp_world_t out, hyp_world_t in);

/* hypervisor_world_delete() : remove world */
extern hyp_world_t hypervisor_world_delete(hyp_world_t id);

#endif /* __VHEX_HYPERVISOR__ */