#include <stdio.h>

#include "ch32fun.h"
#include "ch32v20xhw.h"
#include "ethernetif.h"
#include "lwip/dhcp.h"
#include "lwip/init.h"
#include "lwip/netif.h"
#include "lwip/timeouts.h"
#include "netif/ethernet.h"
#include "systick.h"

#define LED1_PIN 0
#define LED2_PIN 2

#define RCC_PREDIV1_OFFSET 0

struct netif g_netif;

void init_leds() {
  RCC->APB2PCENR |= RCC_APB2Periph_GPIOA;
  GPIOA->CFGLR &= ~((0xf << (4 * 0)) | (0xf << (4 * 2)));
  GPIOA->CFGLR |= (GPIO_Speed_10MHz | GPIO_CNF_OUT_PP) << (4 * 0);
  GPIOA->CFGLR |= (GPIO_Speed_10MHz | GPIO_CNF_OUT_PP) << (4 * 2);
}

int main() {
  SystemInit();

  // 1. HSE (32MHz)
  // 2. PREDIV1 / 4.
  // 3. PLL source = HSE, PLL x15.
  // 4. (32MHz / 4) * 15 = 120MHz SYSCLK

  RCC->INTR = 0x009F0000;
  RCC->CTLR &= ~(RCC_HSE_ON | RCC_PLLON);
  RCC->CFGR0 = 0x00000000;
  RCC->CTLR |= RCC_HSE_ON;

  int timeout;
  for (timeout = 10000; timeout > 0; timeout--) {
    if (RCC->CTLR & RCC_HSERDY) break;  // wait for HSE
  }
  if (timeout == 0) {
    printf("Error: HSE failed to start\n");
    return -1;
  }

  RCC->CFGR0 |= (uint32_t)RCC_PPRE1_DIV2;
  RCC->CFGR2 = ((3) << 0);  // PREDIV1 divisor = 3+1 = 4
  RCC->CFGR0 |= RCC_PLLSource_HSE_Div1 | RCC_PLLMul_15;

  RCC->CTLR |= RCC_PLLON;
  printf("Main PLL enabled. Waiting for lock...\n");
  for (timeout = 10000; timeout > 0; timeout--) {
    if (RCC->CTLR & RCC_PLLRDY) break;
  }
  if (timeout == 0) {
    printf("error: main pll lock failed\n");
    return -1;
  }
  printf("Main PLL Locked\n");

  RCC->CFGR0 = (RCC->CFGR0 & ~RCC_SW) | RCC_SW_PLL;

  while ((RCC->CFGR0 & RCC_SWS) != RCC_SWS_PLL);

  printf("SysClock set to 120MHz\n");

  systick_init();
  init_leds();

  lwip_init();

  ip_addr_t ipaddr, netmask, gw;
  IP4_ADDR(&ipaddr, 0, 0, 0, 0);
  IP4_ADDR(&netmask, 0, 0, 0, 0);
  IP4_ADDR(&gw, 0, 0, 0, 0);

  netif_add(&g_netif, &ipaddr, &netmask, &gw, NULL, &ethernetif_init,
            &ethernet_input);

  netif_set_default(&g_netif);
  netif_set_up(&g_netif);

  dhcp_start(&g_netif);

  ethernetif_init(&g_netif);

  uint32_t last_led_toggle = 0;
  uint32_t last_send_time = 0;
  int led_state = 0;

  while (1) {
    ethernetif_link_poll(&g_netif);

    if (netif_is_link_up(&g_netif)) {
      ethernetif_input(&g_netif);
    }

    sys_check_timeouts();

    // run_tx_test();

    uint32_t now = millis();

    if (now - last_led_toggle > 500) {
      if (led_state) {
        GPIOA->BSHR = (1 << 0);
      } else {
        GPIOA->BSHR = (1 << (0 + 16));
      }
      led_state = !led_state;
      last_led_toggle = now;
    }

    static int ip_printed = 0;
    if (g_netif.ip_addr.addr != 0 && !ip_printed) {
      printf("IP address assigned: %s\n",
             ip4addr_ntoa(netif_ip4_addr(&g_netif)));
      ip_printed = 1;
    }
  }
}