#include <stdarg.h>
#include <stdbool.h>

#include "serial.h"
#include "log.h"

#define LOG_COM COM1

void init_log() {
  //TODO: move old "sys/current.log"
  //TODO: open new "sys/current.log"
}

static const char *const log_prefixes[] = {
  " [USER] ",
  " [INFO] ",
  " [WARN] ",
  "[ERROR] ",
  "[PANIC] ",
};

static inline void logch(char ch) {
  sout(LOG_COM, ch);
  //TODO: write to log file as well
}

static const char hex_table[] = "0123456789abcdef";

void logf(enum log_level level, const char *format, ...) {
  va_list args;
  va_start(args, format);

  const char *log_prefix = log_prefixes[level];
  while (*log_prefix)
    logch(*(log_prefix++));

  for (const char *fi = format; *fi;)
    if (*fi != '%')
      logch(*(fi++));
    else {
      switch (*(fi + 1)) {
      case '%':
        logch('%');
        break;
      case 's':;
        const char *s = va_arg(args, const char *);
        while (*s)
          logch(*(s++));
        break;
      case 'd':;
        const uint32_t d = va_arg(args, uint32_t);
        if (d == 0) {
          logch('0');
          break;
        }
        bool zeros = false;
        for (uint32_t place = 1000000000; place; place /= 10) {
          uint8_t digit = (d / place) % 10;
          if (digit)
            zeros = true;
          if (zeros)
            logch(digit | '0');
        }
        break;
      case 'h':;
        const uint32_t h = va_arg(args, uint32_t);
        uint32_t shift = 32;
        if (*(fi + 2) == 'b') {
          shift = 8;
          ++fi;
        }
        else if (*(fi + 2) == 'w') {
          shift = 16;
          ++fi;
        }
        else if (*(fi + 2) == 'd') {
          ++fi;
        }
        while (shift)
          logch(hex_table[(h >> (shift -= 4)) & 0xf]);
        break;
      default:
        logch('%');
        logch(*(fi + 1));
      }
      fi += 2;
    }

  logch('\n');

  va_end(args);
}