#include <stdint.h>
#include "syscall.h"
#include "cpu.h"
#include "intr.h"
#include "syscall/syscall.h"
#include "proc/proc.h"
#include "kprintf.h"
#include "errors.h"

extern void hal_enable_syscallentry(void);
extern void hal_syscallentry(void);

void hal_syscalldispatch(IntrStackFrame *frame) {
  uint64_t sysnum = frame->regs.rax;
  if (sysnum < SYSCALLS_MAX) {
    SyscallFn fn = SYSCALL_TABLE[sysnum];
    if (fn == NULL) {
      frame->regs.rax = E_BADSYSCALL;
      return;
    }
    int32_t ret = fn(frame->regs.rdi, frame->regs.rsi, frame->regs.rdx,
                     frame->regs.r10, frame->regs.r8,  frame->regs.r9);

    if (sysnum == SYS_QUITPROC) {
      proc_sched((void *)frame);
    }
    frame->regs.rax = *(uint64_t *)&ret;
  }
}

void hal_syscall_init(void) {
  hal_cpu_init(0);
  LocalCpuData *lcd = &HAL_CPUS[0];

  hal_cpu_wrmsr(HAL_CPU_EFER, hal_cpu_rdmsr(HAL_CPU_EFER) | 0x1);
  hal_enable_syscallentry();

  hal_cpu_wrmsr(HAL_CPU_GSBASE, (uint64_t)lcd);
  hal_cpu_wrmsr(HAL_CPU_KGSBASE, (uint64_t)lcd);
  hal_cpu_wrmsr(HAL_CPU_SFMASK, (uint64_t)0);

  hal_cpu_wrmsr(HAL_CPU_LSTAR, (uint64_t)&hal_syscallentry);
}