/* main.c */

#include "asm.h"
#include "main.h"
#include "process.h"
#include "mips4kc.h"
#include "program.h"
#include "registers.h"
#include "scheduler.h"
#include "string.h"
#include "tty3.h"
#include "user.h"

int latest_p = 0;

void call(void (*func)()) {
  func();
}

registers_t regs;

void kinit() {
  kset_registers(&regs);
  init_programs();
  init_PCB();
  char args_other_name[2][MAX_STR_LEN];
  string_memcpy(args_other_name[0], "welcome");

  /* what to run in init */
  // new_p("lcd", args_other_name);
  new_p("console", args_other_name);

  PCB_list[0].status = RUNNING;
  init_UART();
  kset_sr(0x0, 0x8401);
  kload_timer(100*timer_msec);
  call((void *) PCB_list[get_running()].address);
}
void handle_timer_interrupt() {
  int pid = latest_p + 1;
  if (is_supervisor(pid)) {
    check_crashes();
    revive(pid);
  }
  do_delay();
  increase_wait();
  select_process();
  latest_p = get_running();
  if (PCB_list[latest_p].toggle) { PCB_list[latest_p].toggle = 0; }
  else { PCB_list[latest_p].toggle = 1; }
}


void kexception() {
  cause_reg_t cause;
  cause.reg = get_cause();
  registers_t *tmp;
  tmp = kget_registers();
  if (cause.field.exc == 8) {
    syscall_handler(tmp);
    tmp->epc_reg += 4;
  }
  else if (cause.field.ip & 0x80) {
    registers_memcpy(&PCB_list[latest_p].regs, tmp);
    handle_timer_interrupt();
    registers_memcpy(tmp, &PCB_list[latest_p].regs);
    kset_registers(tmp);
    kload_timer(100*timer_msec);
  }
  else if (cause.field.ip & 4) { handle_tty_input(); }
}