#include <stddef.h>
#include <logger.h>
#include <timer.h>
#include <errcode.h>
#include <kmalloc.h>
#include <utils.h>
#include <string.h>
#include <uart.h>
#include <mbox.h>
#include <shell.h>
#include <exec.h>
#include <mman.h>

#define INPUT_BUFLEN 1000

#define PM_PASSWORD 0x5a000000

#define PM_RSTC 0x3F10001c
#define PM_WDOG 0x3F100024

static inline
void _help (void)
{
  uart_puts(
    "help                         : print this help menu" ENDL
    "hello                        : print Hello World!" ENDL
    "hwinfo                       : print hardware info" ENDL
    "memalloc   <size>            : alloate memory and print" ENDL
    "ls                           : list directory contents" ENDL
    "cat        <file>            : concatenate files and print" ENDL
    "exec       <file>            : execute file in usermode" ENDL
    "settimeout <sec> <message...>: pring message after a few seconds" ENDL
    "reboot                       : reboot the device" ENDL
  );
}

static inline
void _hello (void)
{
  uart_puts("hello, world" ENDL);
}

static inline
void _hwinfo (void)
{
  uart_puts(
    "hwinfo: " ENDL
    "board revision: "
  );
  uart_hex(get_board_revision());
  uart_puts(
    ENDL
    "memory base addr: "
  );
  uart_hex(get_memory_base_addr());
  uart_puts(
    ENDL
    "memory size: "
  );
  uart_hex(get_memory_size());
  uart_puts(ENDL);
}

static inline
void _memalloc(size_t size)
{
  void *addr = kmalloc(size);
  uart_puts("size: ");
  uart_hex(size);
  uart_puts(ENDL);

  uart_puts("addr: ");
  uart_hex((uint64_t)addr);
  uart_puts(ENDL);
}

static inline
void _ls_initrd_callback(file_node_t *tr)
{
  uart_puts(tr->filename);
  uart_puts(ENDL);
}

static inline
void _ls(file_node_t *root)
{
  initrd_traverse(root, _ls_initrd_callback);
}

static inline
void _cat(file_node_t *root, const char *filename)
{
  file_node_t *tr = initrd_get(root, filename);
  if (tr) {
    uart_puts((char *)tr->filecontent);
  } else {
    exit(ERR_NOT_EXIST);
  }
}

static inline
void _exec(file_node_t *root, const char *filename)
{
  file_node_t *tr = initrd_get(root, filename);
  if (tr) {
    void *userspace = allocate_page(1 << 6);
    memcpy(userspace, tr->filecontent, tr->filesize);
    user_exec(userspace, userspace + (1 << (12 + 6)) - 8);
    kfree(userspace);
  } else {
    exit(ERR_NOT_EXIST);
  }
}

static inline
void _settimeout_cb_func(uint64_t args)
{
  vector_t *v = (void *)args;
  for (int i = 2; i < (int)v->size; ++i) {
    uart_puts(VEC_AT(char, v, i));
    uart_puts(" ");
  }
  uart_puts(ENDL);
}

static inline
void _settimeout(int32_t sec, vector_t *args)
{
  uint64_t cntpct_el0, cntfrq_el0;
  R_SYSREG(cntpct_el0, cntpct_el0);
  R_SYSREG(cntfrq_el0, cntfrq_el0);

  task_t task = (task_t){
    .firing_tick = cntpct_el0 + sec * cntfrq_el0,
    .interval = sec * cntfrq_el0,
    .repeat = 1,

    .func = _settimeout_cb_func,
    .param = (uint64_t)args,
  };
  add_task(task);
}

static inline
void _set(long addr, unsigned int value) {
  volatile unsigned int* point = (unsigned int*)addr;
  *point = value;
}

static inline
void _reset(int tick) {               // reboot after watchdog timer expire
  _set(PM_RSTC, PM_PASSWORD | 0x20);  // full reset
  _set(PM_WDOG, PM_PASSWORD | tick);  // number of watchdog tick
}

static inline
void _reboot(void)
{
  _reset(1 << 16);
}

char *_shell_buf = (char *)0x0;
int _shell_sz = 0;

static inline
int _shell_operations(char ch)
{
  switch (ch) {
  case 0x7f:
    if (_shell_sz > 0) {
      --_shell_sz;
      uart_puts("\b \b");
    }
    return true;
  default:
  }
  return false;
}

int shell(file_node_t *initrd_root)
{
  uart_puts("# ");
  char ch;
  _shell_buf = kmalloc(INPUT_BUFLEN * sizeof(char));
  _shell_sz = 0;
  while ((ch = uart_getc()) != '\n') {
    if (_shell_operations(ch))
      continue;
    _shell_buf[_shell_sz++] = ch;
    uart_putb((const uint8_t *)&ch, 1);
  }
  uart_puts(ENDL);
  _shell_buf[_shell_sz] = ' ';

  vector_t *args = make_vector(0);
  for (char *saveptr = 0x0, *tok = strtok_r(_shell_buf, " ", &saveptr);
       tok; tok = strtok_r((char *)0x0, " ", &saveptr)) {
    VEC_PUSH(args, tok);
    LOG(tok);
  }

  // DEBUG("ENDL");
  CLEAN;

  char *cmd = args->size ? VEC_AT(char, args, 0) : (char *)0x0;
  if (!strcmp(cmd, "help")) {
    _help();
  } else if (!strcmp(cmd, "hello")) {
    _hello();
  } else if (!strcmp(cmd, "hwinfo")) {
    _hwinfo();
  } else if (!strcmp(cmd, "memalloc") && args->size >= 2){
    char *p1 = VEC_AT(char, args, 1);
    _memalloc((size_t)atoi32(p1));
  } else if (!strcmp(cmd, "ls")) {
    _ls(initrd_root);
  } else if (!strcmp(cmd, "cat") && args->size >= 2) {
    char *p1 = VEC_AT(char, args, 1);
    _cat(initrd_root, p1);
  } else if (!strcmp(cmd, "exec") && args->size >= 2) {
    char *p1 = VEC_AT(char, args, 1);
    _exec(initrd_root, p1);
  } else if (!strcmp(cmd, "settimeout") && args->size >= 2) {
    char *p1 = VEC_AT(char, args, 1);
    _settimeout(atoi32(p1), args);
  } else if (!strcmp(cmd, "reboot")) {
    _reboot();
  }
  
  return true;
}