#include "hardware/clocks.h"
#include "hardware/rtc.h"
#include "hardware/spi.h"
#include "lwip/apps/sntp.h"
#include "lwip/err.h"
#include "lwip/ip_addr.h"
#include "pico/cyw43_arch.h"
#include "pico/stdlib.h"
#include "pico/util/datetime.h"
#include "wifi_conf.h"
#include <lwip/arch.h>
#include <pico/stdio.h>
#include <stdio.h>
#include "hardware/pwm.h"
#include "hardware/adc.h"

#include "lwip/dns.h"
#include "lwip/tcp.h"
#include "net_utils.h"
#include "timezones.h"
#include "spi.h"
#include "display.h"
#include "pins.h"
#include "control.h"


#define NTP_DELTA 2208988800UL

volatile u16_t timezone_index = 353;

extern "C" void sync_system_time(unsigned int sec, unsigned int usec) {
    if (sec == 0) {
        printf("SNTP: Invalid timestamp received\n");
        return;
    }

    printf("SNTP callback received: %lu\n", (unsigned long)sec);

    // Convert NTP timestamp to Unix timestamp
    time_t unix_time = (time_t)(sec - NTP_DELTA);


    struct tm *time_info = gmtime(&unix_time);
    if (time_info == NULL) {
        printf("SNTP: Invalid timestamp %lu\n", (unsigned long)sec);
        return;
    }

    printf("Got SNTP response: %02d/%02d/%04d %02d:%02d:%02d\n",
           time_info->tm_mday, time_info->tm_mon + 1, time_info->tm_year + 1900,
           time_info->tm_hour, time_info->tm_min, time_info->tm_sec);

    datetime_t dt = {
        .year = static_cast<int16_t>(time_info->tm_year + 1900),
        .month = static_cast<int8_t>(time_info->tm_mon + 1),
        .day = static_cast<int8_t>(time_info->tm_mday),
        .dotw = static_cast<int8_t>(time_info->tm_wday),
        .hour = static_cast<int8_t>(time_info->tm_hour),
        .min = static_cast<int8_t>(time_info->tm_min),
        .sec = static_cast<int8_t>(time_info->tm_sec)
    };

  timezone_offset(timezone_index, dt);

    // Set RTC
    if (rtc_set_datetime(&dt)) {
        printf("SNTP: Time synchronized to %04d-%02d-%02d %02d:%02d:%02d %s\n",
               dt.year, dt.month, dt.day, dt.hour, dt.min, dt.sec,
               "Local");
    } else {
        printf("SNTP: Failed to set RTC\n");
    }


  // Sanity checks
  if (dt.year < 2020 || dt.year > 2100 || dt.month < 1 || dt.month > 12 ||
      dt.day < 1 || dt.day > 31 || dt.hour > 23 || dt.min > 59 || dt.sec > 59) {
    printf("SNTP: Invalid date/time components\n");
    return;
      }

  // Set RTC with error handling
  if (rtc_set_datetime(&dt)) {
    printf("SNTP: Time synchronized to %04d-%02d-%02d %02d:%02d:%02d %s\n",
           dt.year, dt.month, dt.day, dt.hour, dt.min, dt.sec,
           "Local");
  } else {
    printf("SNTP: Failed to set RTC\n");
  }
}

int main() {
  stdio_init_all();
  if (cyw43_arch_init()) {
    return 1;
  }
  rtc_init();
  gpio_init(KNOB_PW_PIN);
  gpio_set_dir(KNOB_PW_PIN, GPIO_OUT);
  gpio_put(KNOB_PW_PIN,1);

  adc_init();
  adc_gpio_init(KNOB_SIG_PIN);
  adc_select_input(0);

  // PWM for PC speeker
  gpio_set_function(11, GPIO_FUNC_PWM);


  // sign of life
  cyw43_arch_gpio_put(CYW43_WL_GPIO_LED_PIN, true);

  display_start();

  // Timer example code - This example fires off the callback after 2000ms
  // add_alarm_in_ms(2000, alarm_callback, NULL, false);

  printf("connecting to wifi\n");
  print_time(); // show NO SYNC ERROR
  // connect to wifi
  cyw43_arch_enable_sta_mode();
  if (cyw43_arch_wifi_connect_timeout_ms(wifi_ssid, wifi_pass,
                                         CYW43_AUTH_WPA2_AES_PSK, 30000)) {
    return 1;
  }

  printf("IP: %s\n", ip4addr_ntoa(netif_ip_addr4(netif_default)));
  printf("Mask: %s\n", ip4addr_ntoa(netif_ip_netmask4(netif_default)));
  printf("Gateway: %s\n", ip4addr_ntoa(netif_ip_gw4(netif_default)));

  {
    ip_addr_t ip_addr;
    IP_ADDR4(&ip_addr, 1, 1, 1, 1);
    dns_setserver(0, &ip_addr);

    IP_ADDR4(&ip_addr, 8, 8, 8, 8);
    dns_setserver(1, &ip_addr);

    printf("Initializing SNTP\n");
    sntp_setoperatingmode(SNTP_OPMODE_POLL);
    sntp_init();

    dns_resolve_sync("ntp.cesnet.cz", &ip_addr, 10000);
    sntp_setserver(0, &ip_addr);

    dns_resolve_sync("ntp0.fau.de", &ip_addr, 10000);
    sntp_setserver(1, &ip_addr);
  }

  printf("SNTP initialized, waiting for time sync...\n");

  uint slice_num = pwm_gpio_to_slice_num(11);

  // Generate a 1kHz tone
  // 125MHz / 125 = 1MHz PWM clock
  pwm_set_clkdiv(slice_num, 125.0f);

  // 1MHz / 1000 = 1kHz audio frequency
  pwm_set_wrap(slice_num, 1000);

  // 50% duty cycle for square wave
  pwm_set_chan_level(slice_num, PWM_CHAN_B, 500);

  // Enable PWM
  pwm_set_enabled(slice_num, true);


  while (true) {
    print_time();
    printf("knob: %d\n",get_knob_percentage());
    pwm_set_wrap(slice_num, 10*get_knob_percentage());

    sleep_ms(500);
  }
  cyw43_arch_lwip_end();
  return 0;
}