#pragma once

#include "types.h"

/* Syscall Numbers (passed in RAX) */
#define SYS_IPC_CALL        1   /* Synchronous call: send message & wait for reply */
#define SYS_IPC_REPLY_RECV  2   /* Server fast-path: reply to current and wait next */
#define SYS_IPC_SEND        3   /* Asynchronous/non-blocking send */
#define SYS_IPC_RECV        4   /* Block waiting for incoming message */
#define SYS_MEM_MAP         5   /* Map memory / shared memory region */
#define SYS_CAP_GRANT       6   /* Delegate capability to CNode */
#define SYS_THREAD_YIELD    7   /* Yield CPU slice */
#define SYS_THREAD_EXIT     8   /* Terminate current thread */
#define SYS_LOG_DEBUG       9   /* Direct Ring 0 debug print */

#ifndef __ASSEMBLER__

#ifdef __cplusplus
extern "C" {
#endif

/* Low-level inline syscall invocations adhering to System V AMD64 ABI + Fast-Path */

static inline sysret_t sys_ipc_call_raw(cap_t dest_cap, uint64_t msg_code,
                                        uint64_t arg0, uint64_t arg1,
                                        uint64_t arg2, uint64_t arg3,
                                        uint64_t *out0, uint64_t *out1) {
    register uint64_t rax __asm__("rax") = SYS_IPC_CALL;
    register uint64_t rdi __asm__("rdi") = dest_cap;
    register uint64_t rsi __asm__("rsi") = msg_code;
    register uint64_t rdx __asm__("rdx") = arg0;
    register uint64_t r8  __asm__("r8")  = arg1;
    register uint64_t r9  __asm__("r9")  = arg2;
    register uint64_t r10 __asm__("r10") = arg3;

    __asm__ volatile(
        "syscall"
        : "+r"(rax), "+r"(rdx), "+r"(r8)
        : "r"(rdi), "r"(rsi), "r"(r9), "r"(r10)
        : "rcx", "r11", "memory"
    );

    if (out0) *out0 = rdx;
    if (out1) *out1 = r8;
    return (sysret_t)rax;
}

static inline sysret_t sys_ipc_reply_recv_raw(cap_t listen_ep, uint64_t reply_to_tid,
                                              uint64_t reply_val0, uint64_t reply_val1,
                                              uint64_t *sender_tid, uint64_t *opcode,
                                              uint64_t *arg0, uint64_t *arg1) {
    register uint64_t rax __asm__("rax") = SYS_IPC_REPLY_RECV;
    register uint64_t rdi __asm__("rdi") = listen_ep;
    register uint64_t rsi __asm__("rsi") = reply_to_tid;
    register uint64_t rdx __asm__("rdx") = reply_val0;
    register uint64_t r8  __asm__("r8")  = reply_val1;

    __asm__ volatile(
        "syscall"
        : "+r"(rax), "+r"(rdi), "+r"(rsi), "+r"(rdx), "+r"(r8)
        :
        : "rcx", "r11", "memory"
    );

    if (sender_tid) *sender_tid = rdi;
    if (opcode) *opcode = rsi;
    if (arg0) *arg0 = rdx;
    if (arg1) *arg1 = r8;
    return (sysret_t)rax;
}

static inline sysret_t sys_yield(void) {
    register uint64_t rax __asm__("rax") = SYS_THREAD_YIELD;
    __asm__ volatile("syscall" : "+r"(rax) : : "rcx", "r11", "memory");
    return (sysret_t)rax;
}

static inline void sys_exit(int code) {
    register uint64_t rax __asm__("rax") = SYS_THREAD_EXIT;
    register uint64_t rdi __asm__("rdi") = (uint64_t)code;
    __asm__ volatile("syscall" : "+r"(rax) : "r"(rdi) : "rcx", "r11", "memory");
    __builtin_unreachable();
}

static inline sysret_t sys_log_debug(const char *msg, size_t len) {
    register uint64_t rax __asm__("rax") = SYS_LOG_DEBUG;
    register uint64_t rdi __asm__("rdi") = (uint64_t)msg;
    register uint64_t rsi __asm__("rsi") = (uint64_t)len;
    __asm__ volatile("syscall" : "+r"(rax) : "r"(rdi), "r"(rsi) : "rcx", "r11", "memory");
    return (sysret_t)rax;
}

#ifdef __cplusplus
}
#endif

#endif /* __ASSEMBLER__ */