#ifndef _JOVE_API_SYSCALL_H
#define _JOVE_API_SYSCALL_H 1

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

#include "obj.h"

/* General syscall behavior:
 * If the message passed is not a JOVE_OBJ_MESSAGE type, the kernel will return EBADOBJ.
 * If the message is too small to hold the target path, the kernel will return ETOOSMALL.
 * If the target path does not target a real object, the kernel will return EBADPATH.
 * If the target does not support the callid, the kernel will return EBADARG.
 * Otherwise, behavior depends on the syscall specified in callid.
 * */

struct syscall_header
{
    uint16_t callid;
    uint16_t pathlen;
    objpath_part_t path[];
};

/* If the message is too small for data, the kernel will return ETOOSMALL.
 * */
struct syscall_generic_write
{
    size_t len;
    char data[];
};

/* If the message is too small for path, the kernel will return ETOOSMALL.
 * If the path does not point to an object, the kernel will return EBADPATH.
 * */
struct syscall_generic_objpath
{
    uint16_t pathlen;
    objpath_part_t path[];
};

enum
{
    _SYSCALL_UNTYPED_BADCALL = 0,
    SYSCALL_UNTYPED_ADDRESS,
    SYSCALL_UNTYPED_SIZE,
    SYSCALL_UNTYPED_SPLIT,
    SYSCALL_UNTYPED_MERGE,
    SYSCALL_UNTYPED_RETYPE,
};

#define SYSCALL_PERM_UNTYPED_ADDRESS JOVE_PERM_READ
#define SYSCALL_PERM_UNTYPED_SIZE JOVE_PERM_READ
#define SYSCALL_PERM_UNTYPED_SPLIT (JOVE_PERM_WRITE | JOVE_PERM_MUTATE)
#define SYSCALL_PERM_UNTYPED_MERGE (JOVE_PERM_WRITE | JOVE_PERM_MUTATE)

struct syscall_untyped_split
{
    size_t bytes;
    uint16_t dest_pathlen;
    objpath_part_t dest_path[];
};

enum
{
    _SYSCALL_OBJDIR_BADCALL = 0,
    SYSCALL_OBJDIR_OBJTYPE,
};

#define SYSCALL_PERM_OBJDIR_OBJTYPE JOVE_PERM_READ

enum
{
    _SYSCALL_PAGEDIR_NONE = 0,
    SYSCALL_PAGEDIR_MAP_FRAME,
    SYSCALL_PAGEDIR_MAP_TABLE,
    SYSCALL_PAGEDIR_MAP_SHMEM,
    SYSCALL_PAGEDIR_UNMAP_FRAME,
    SYSCALL_PAGEDIR_UNMAP_TABLE,
    SYSCALL_PAGEDIR_UNMAP_SHMEM,
};

#define SYSCALL_PERM_PAGEDIR_MAP_FRAME (JOVE_PERM_READ | JOVE_PERM_WRITE)
#define SYSCALL_PERM_PAGEDIR_MAP_TABLE (JOVE_PERM_READ | JOVE_PERM_WRITE)
#define SYSCALL_PERM_PAGEDIR_MAP_SHMEM (JOVE_PERM_READ | JOVE_PERM_WRITE)
#define SYSCALL_PERM_PAGEDIR_UNMAP_FRAME (JOVE_PERM_READ | JOVE_PERM_WRITE)
#define SYSCALL_PERM_PAGEDIR_UNMAP_TABLE (JOVE_PERM_READ | JOVE_PERM_WRITE)
#define SYSCALL_PERM_PAGEDIR_UNMAP_SHMEM (JOVE_PERM_READ | JOVE_PERM_WRITE)

struct syscall_pagedir_flags
{
    uint8_t writeable : 1;
    uint8_t executable : 1;
    uint8_t flg_unused : 6;
};

struct syscall_pagedir_map
{
    struct syscall_pagedir_flags page_flags;
    uint16_t untyped_pathlen;
    uintptr_t virtual_address;
    objpath_part_t untyped_path[];
};

struct syscall_pagedir_map_shmem
{
    struct syscall_pagedir_flags page_flags;
    uint8_t page_offset;
    uint16_t shmem_pathlen;
    uintptr_t virtual_address;
    objpath_part_t shmem_path[];
};

struct syscall_pagedir_unmap
{
    uintptr_t virtual_address;
    uint16_t none_pathlen;
    objpath_part_t none_path[];
};

enum
{
    _SYSCALL_VTT_NONE = 0,
    SYSCALL_VTT_WRITE
};

#endif