/*
 * Copyright 2024 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "boot_tests.h"

#include "board/board.h"
#include "drivers/button.h"
#include "drivers/dbgserial.h"
#include "drivers/flash.h"
#include "system/bootbits.h"
#include "system/rtc_registers.h"
#include "util/misc.h"

#include "stm32f4xx.h"

#include <stdint.h>
#include <inttypes.h>
#include <stdbool.h>

static const int STUCK_BUTTON_THRESHOLD = 5;

bool is_button_stuck(void) {
  // We store how many times each button has been pressed on previous boots in this
  // rtc backup register. Every time when we boot without that button pressed that
  // counter gets cleared. If the byte reaches 5, return a failure.

  uint32_t button_counter_register = RTC_ReadBackupRegister(STUCK_BUTTON_REGISTER);
  uint8_t* button_counter = (uint8_t*) (&button_counter_register);
  bool result = false;

  for (int button_id = 0; button_id < NUM_BUTTONS; button_id++) {
    if (!button_is_pressed(button_id)) {
      button_counter[button_id] = 0;
      continue;
    }

    if (button_counter[button_id] >= STUCK_BUTTON_THRESHOLD) {
      dbgserial_putstr("Stuck button register is invalid, clearing.");
      dbgserial_print_hex(button_counter_register);

      RTC_WriteBackupRegister(STUCK_BUTTON_REGISTER, 0);
      return false;
    }

    button_counter[button_id] += 1;

    if (button_counter[button_id] >= STUCK_BUTTON_THRESHOLD) {
      dbgserial_print("Button id ");
      dbgserial_print_hex(button_id);
      dbgserial_putstr("is stuck!");
      result = true;
    }
  }

  if (button_counter_register != 0) {
    dbgserial_print("Button was pushed on boot. Button counter: ");
    dbgserial_print_hex(button_counter_register);
    dbgserial_newline();
  }

  RTC_WriteBackupRegister(STUCK_BUTTON_REGISTER, button_counter_register);
  return result;
}

bool is_flash_broken(void) {
  return !flash_sanity_check();
}