// Copyright (c) 2023 Cesanta Software Limited
// All rights reserved

#include "hal.h"
#include "mongoose.h"

static const char *s_url = "mqtt://broker.hivemq.com:1883";
static const char *s_sub_topic = "mg/+/test";     // Publish topic
static const char *s_pub_topic = "mg/clnt/test";  // Subscribe topic
static const uint8_t s_qos = 1;                   // MQTT QoS
static struct mg_connection *s_conn;              // Client connection

void SystemInit(void) {  // Called automatically by startup code
  clock_init();
  rng_init();
}

static volatile uint64_t s_ticks;  // Milliseconds since boot
void SysTick_Handler(void) {       // SyStick IRQ handler, triggered every 1ms
  s_ticks++;
}

uint64_t mg_millis(void) {  // Let Mongoose use our uptime function
  return s_ticks;           // Return number of milliseconds since boot
}

void mg_random(void *buf, size_t len) {  // Use on-board RNG
  for (size_t n = 0; n < len; n += sizeof(uint32_t)) {
    uint32_t r = rng_read();
    memcpy((char *) buf + n, &r, n + sizeof(r) > len ? len - n : sizeof(r));
  }
}

static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
  if (ev == MG_EV_OPEN) {
    MG_INFO(("%lu CREATED", c->id));
    // c->is_hexdumping = 1;
  } else if (ev == MG_EV_ERROR) {
    // On error, log error message
    MG_ERROR(("%lu ERROR %s", c->id, (char *) ev_data));
  } else if (ev == MG_EV_MQTT_OPEN) {
    // MQTT connect is successful
    struct mg_str subt = mg_str(s_sub_topic);
    struct mg_str pubt = mg_str(s_pub_topic), data = mg_str("hello");
    MG_INFO(("%lu CONNECTED to %s", c->id, s_url));
    struct mg_mqtt_opts sub_opts;
    memset(&sub_opts, 0, sizeof(sub_opts));
    sub_opts.topic = subt;
    sub_opts.qos = s_qos;
    mg_mqtt_sub(c, &sub_opts);
    MG_INFO(("%lu SUBSCRIBED to %.*s", c->id, (int) subt.len, subt.ptr));
    struct mg_mqtt_opts pub_opts;
    memset(&pub_opts, 0, sizeof(pub_opts));
    pub_opts.topic = pubt;
    pub_opts.message = data;
    pub_opts.qos = s_qos, pub_opts.retain = false;
    mg_mqtt_pub(c, &pub_opts);
    MG_INFO(("%lu PUBLISHED %.*s -> %.*s", c->id, (int) data.len, data.ptr,
             (int) pubt.len, pubt.ptr));
  } else if (ev == MG_EV_MQTT_MSG) {
    // When we get echo response, print it
    struct mg_mqtt_message *mm = (struct mg_mqtt_message *) ev_data;
    MG_INFO(("%lu RECEIVED %.*s <- %.*s", c->id, (int) mm->data.len,
             mm->data.ptr, (int) mm->topic.len, mm->topic.ptr));
  } else if (ev == MG_EV_CLOSE) {
    MG_INFO(("%lu CLOSED", c->id));
    s_conn = NULL;  // Mark that we're closed
  }
  (void) fn_data;
}

// Timer function - recreate client connection if it is closed
static void timer_fn(void *arg) {
  struct mg_mgr *mgr = (struct mg_mgr *) arg;
  struct mg_mqtt_opts opts = {.clean = true,
                              .qos = s_qos,
                              .topic = mg_str(s_pub_topic),
                              .version = 4,
                              .message = mg_str("bye")};
  if (s_conn == NULL) s_conn = mg_mqtt_connect(mgr, s_url, &opts, fn, NULL);
}

int main(void) {
  gpio_input(BUTTON_PIN);
  gpio_output(LED_PIN);
  uart_init(UART_DEBUG, 115200);
  ethernet_init();
  MG_INFO(("Starting, CPU freq %g MHz", (double) clock_sys_freq() / 1000000));

  struct mg_mgr mgr;        // Initialise
  mg_mgr_init(&mgr);        // Mongoose event manager
  mg_log_set(MG_LL_DEBUG);  // Set log level

  // Initialise Mongoose network stack
  struct mg_tcpip_driver_same54_data driver_data = {.mdc_cr = 5};
  struct mg_tcpip_if mif = {
      .mac = GENERATE_LOCALLY_ADMINISTERED_MAC() /*{2, 3, 4, 5, 6, 7}*/,
      // Uncomment below for static configuration:
      // .ip = mg_htonl(MG_U32(192, 168, 0, 223)),
      // .mask = mg_htonl(MG_U32(255, 255, 255, 0)),
      // .gw = mg_htonl(MG_U32(192, 168, 0, 1)),
      .driver = &mg_tcpip_driver_same54,
      .driver_data = &driver_data};
  mg_tcpip_init(&mgr, &mif);

  MG_INFO(("MAC: %M. Waiting for IP...", mg_print_mac, mif.mac));
  while (mif.state != MG_TCPIP_STATE_READY) {
    mg_mgr_poll(&mgr, 0);
  }

  MG_INFO(("Initialising application..."));
  mg_timer_add(&mgr, 3000, MG_TIMER_REPEAT | MG_TIMER_RUN_NOW, timer_fn, &mgr);

  MG_INFO(("Starting event loop"));
  for (;;) {
    mg_mgr_poll(&mgr, 0);
  }

  return 0;
}