// Provider communication — mDNS discovery, device registration, screen fetch.

#include "provider.hpp"

#include <cstdio>
#include <cstring>

#include "esp_log.h"
#include "mdns.h"
#include "sdkconfig.h"

#include "http_client.hpp"
#include "network.hpp"

static const char *TAG = "Provider";

// ── mDNS Provider Discovery ────────────────────────────────────────────────

// Resolve the Provider's IP via mDNS. Returns true and fills `out_ip` on
// success. Falls back to CONFIG_CALENDINK_PROVIDER_FALLBACK_IP if set.
static bool resolve_provider_ip(char *out_ip, size_t out_ip_len)
{
  ESP_LOGI(TAG, "Resolving Provider via mDNS: %s.local",
           CONFIG_CALENDINK_PROVIDER_MDNS_HOSTNAME);

  esp_err_t err = mdns_init();
  if (err != ESP_OK)
  {
    ESP_LOGE(TAG, "mDNS init failed: %s", esp_err_to_name(err));
    goto fallback;
  }

  {
    esp_ip4_addr_t addr = {};
    err = mdns_query_a(CONFIG_CALENDINK_PROVIDER_MDNS_HOSTNAME, 5000, &addr);
    if (err == ESP_OK)
    {
      snprintf(out_ip, out_ip_len, IPSTR, IP2STR(&addr));
      ESP_LOGI(TAG, "Provider resolved: %s", out_ip);
      return true;
    }

    ESP_LOGW(TAG, "mDNS resolution failed: %s", esp_err_to_name(err));
  }

fallback:
  if (strlen(CONFIG_CALENDINK_PROVIDER_FALLBACK_IP) > 0)
  {
    strlcpy(out_ip, CONFIG_CALENDINK_PROVIDER_FALLBACK_IP, out_ip_len);
    ESP_LOGW(TAG, "Using fallback IP: %s", out_ip);
    return true;
  }

  ESP_LOGE(TAG, "No fallback IP configured. Cannot reach Provider.");
  return false;
}

// ── Provider Communication Test ─────────────────────────────────────────────

void test_provider_communication(void)
{
  // 1. Resolve Provider IP
  char provider_ip[16] = {};
  if (!resolve_provider_ip(provider_ip, sizeof(provider_ip)))
  {
    return;
  }

  uint16_t provider_port = CONFIG_CALENDINK_PROVIDER_PORT;

  // 2. Get our own MAC address
  uint8_t mac_bytes[6] = {};
  esp_err_t err = get_mac_address(mac_bytes);
  if (err != ESP_OK)
  {
    ESP_LOGE(TAG, "Failed to get WiFi MAC: %s", esp_err_to_name(err));
    return;
  }

  char mac_str[18] = {};
  snprintf(mac_str, sizeof(mac_str), "%02X:%02X:%02X:%02X:%02X:%02X",
           mac_bytes[0], mac_bytes[1], mac_bytes[2], mac_bytes[3], mac_bytes[4],
           mac_bytes[5]);
  ESP_LOGI(TAG, "Client MAC: %s", mac_str);

  // 3. Register with Provider: POST /api/devices/register
  {
    char *url =
        http_build_url(provider_ip, provider_port, "/api/devices/register");
    if (url == nullptr)
    {
      return;
    }

    char json_body[64] = {};
    snprintf(json_body, sizeof(json_body), "{\"mac\":\"%s\"}", mac_str);

    http_text_response_t resp = {};
    err = http_post_json(url, json_body, &resp);

    if (err == ESP_OK)
    {
      ESP_LOGI(TAG, "Register response (%d): %s", resp.status_code,
               resp.body ? resp.body : "(empty)");
    }
    else
    {
      ESP_LOGE(TAG, "Register request failed: %s", esp_err_to_name(err));
    }

    free(resp.body);
    free(url);
  }

  // 4. Fetch screen image: GET /api/devices/screen.png?mac=XX:XX:XX:XX:XX:XX
  {
    char path[80] = {};
    snprintf(path, sizeof(path), "/api/devices/screen.png?mac=%s", mac_str);

    char *url = http_build_url(provider_ip, provider_port, path);
    if (url == nullptr)
    {
      return;
    }

    http_binary_response_t resp = {};
    err = http_get_binary(url, &resp);

    if (err == ESP_OK)
    {
      ESP_LOGI(TAG, "Screen image response (%d): %zu bytes", resp.status_code,
               resp.data_len);
    }
    else
    {
      ESP_LOGE(TAG, "Screen image request failed: %s", esp_err_to_name(err));
    }

    free(resp.data);
    free(url);
  }
}