#include <vhex/hypervisor.h>
#include <vhex/drivers/cpu.h>

#include <vhex/display.h>

/* hypervisor_world_switch() : perform a world switch */
//TODO: handle shared drivers
int hypervisor_world_switch(hyp_world_t out, hyp_world_t in)
{
	struct vhex_world *win;
	struct vhex_world *wout;
	struct vhex_driver *dtable;


	wout = hypervisor_world_get(out);
	win = hypervisor_world_get(in);
	if (wout == NULL || win == NULL)
		return (hyp_world_not_found);
	if (in == out)
		return (0);

	cpu_atomic_start();
	dtable = vhex_driver_table();
	for (int i = 0; i < vhex_driver_count(); ++i) {
		if (dtable[i].hpowered != NULL
				&& dtable[i].hpowered() == false) {
			wout->driver[i].flags = HYP_WORLD_DRV_UNUSED;
			continue;
		}
		dtable[i].hsave(wout->driver[i].context);
		wout->driver[i].flags = HYP_WORLD_DRV_USED;
	}
	for (int i = 0; i < vhex_driver_count(); ++i) {
		if (HYP_WORLD_STATUS_STATE(win->status)
				== HYP_WORLD_STATUS_STATE_UNINIT) {
			if (dtable[i].configure != NULL)
				dtable[i].configure(win->driver[i].context);
			win->driver[i].flags = dtable[i].default_flag;
		}
		if (win->driver[i].flags == HYP_WORLD_DRV_UNUSED) {
			if (dtable[i].hpowered() == true)
				dtable[i].hpoweroff();
			continue;
		}
		if (dtable[i].hpowered != NULL && dtable[i].hpowered() == false)
			dtable[i].hpoweron();
		dtable[i].hrestore(win->driver[i].context);
	}
	HYP_WORLD_STATUS_SET_STATE(win->status, HYP_WORLD_STATUS_STATE_USED);
	HYP_WORLD_STATUS_SET_STATE(wout->status, HYP_WORLD_STATUS_STATE_USED);
	cpu_atomic_end();
}