esphome-lsm6ds/esphome/components/wifi/wifi_component.h

#pragma once

#include "esphome/core/defines.h"
#ifdef USE_WIFI
#include "esphome/components/network/ip_address.h"
#include "esphome/core/automation.h"
#include "esphome/core/component.h"
#include "esphome/core/helpers.h"
#ifdef USE_ESP32
#include "esphome/core/lock_free_queue.h"
#endif
#include "esphome/core/string_ref.h"

#include <span>
#include <string>
#include <type_traits>
#include <vector>

#ifdef USE_LIBRETINY
#include <WiFi.h>
#endif

#if defined(USE_ESP32) && defined(USE_WIFI_WPA2_EAP)
#if ESP_IDF_VERSION >= ESP_IDF_VERSION_VAL(5, 1, 0)
#include <esp_eap_client.h>
#else
#include <esp_wpa2.h>
#endif
#endif

#ifdef USE_ESP8266
#include <ESP8266WiFi.h>
#include <ESP8266WiFiType.h>

#if defined(USE_ESP8266) && USE_ARDUINO_VERSION_CODE < VERSION_CODE(2, 4, 0)
extern "C" {
#include <user_interface.h>
};
#endif
#endif

#ifdef USE_RP2040
extern "C" {
#include "cyw43.h"
#include "cyw43_country.h"
#include "pico/cyw43_arch.h"
}

#include <WiFi.h>
#endif

#if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
#include <esp_wifi_types.h>
#endif

#if defined(USE_ESP32) && defined(USE_WIFI_RUNTIME_POWER_SAVE)
#include <freertos/FreeRTOS.h>
#include <freertos/semphr.h>
#endif

namespace esphome::wifi {

/// Sentinel value for RSSI when WiFi is not connected
static constexpr int8_t WIFI_RSSI_DISCONNECTED = -127;

/// Buffer size for SSID (IEEE 802.11 max 32 bytes + null terminator)
static constexpr size_t SSID_BUFFER_SIZE = 33;

struct SavedWifiSettings {
  char ssid[33];
  char password[65];
} PACKED;  // NOLINT

struct SavedWifiFastConnectSettings {
  uint8_t bssid[6];
  uint8_t channel;
  int8_t ap_index;
} PACKED;  // NOLINT

enum WiFiComponentState : uint8_t {
  /** Nothing has been initialized yet. Internal AP, if configured, is disabled at this point. */
  WIFI_COMPONENT_STATE_OFF = 0,
  /** WiFi is disabled. */
  WIFI_COMPONENT_STATE_DISABLED,
  /** WiFi is in cooldown mode because something went wrong, scanning will begin after a short period of time. */
  WIFI_COMPONENT_STATE_COOLDOWN,
  /** WiFi is in STA-only mode and currently scanning for APs. */
  WIFI_COMPONENT_STATE_STA_SCANNING,
  /** WiFi is in STA(+AP) mode and currently connecting to an AP. */
  WIFI_COMPONENT_STATE_STA_CONNECTING,
  /** WiFi is in STA(+AP) mode and successfully connected. */
  WIFI_COMPONENT_STATE_STA_CONNECTED,
  /** WiFi is in AP-only mode and internal AP is already enabled. */
  WIFI_COMPONENT_STATE_AP,
};

enum class WiFiSTAConnectStatus : int {
  IDLE,
  CONNECTING,
  CONNECTED,
  ERROR_NETWORK_NOT_FOUND,
  ERROR_CONNECT_FAILED,
};

/// Tracks the current retry strategy/phase for WiFi connection attempts
enum class WiFiRetryPhase : uint8_t {
  /// Initial connection attempt (varies based on fast_connect setting)
  INITIAL_CONNECT,
#ifdef USE_WIFI_FAST_CONNECT
  /// Fast connect mode: cycling through configured APs (config-only, no scan)
  FAST_CONNECT_CYCLING_APS,
#endif
  /// Explicitly hidden networks (user marked as hidden, try before scanning)
  EXPLICIT_HIDDEN,
  /// Scan-based: connecting to best AP from scan results
  SCAN_CONNECTING,
  /// Retry networks not found in scan (might be hidden)
  RETRY_HIDDEN,
  /// Restarting WiFi adapter to clear stuck state
  RESTARTING_ADAPTER,
};

/// Tracks post-connect roaming state machine
enum class RoamingState : uint8_t {
  /// Not roaming, waiting for next check interval
  IDLE,
  /// Scanning for better AP
  SCANNING,
  /// Attempting to connect to better AP found in scan
  CONNECTING,
  /// Roam connection failed, reconnecting to any available AP
  RECONNECTING,
};

/// Controls how RETRY_HIDDEN phase selects networks to try
enum class RetryHiddenMode : uint8_t {
  /// Normal mode: scan completed, only try networks NOT visible in scan results
  /// (truly hidden networks that need probe requests)
  SCAN_BASED,
  /// Blind retry mode: scanning disabled (captive portal/improv active),
  /// try ALL configured networks sequentially without consulting scan results
  BLIND_RETRY,
};

/// Struct for setting static IPs in WiFiComponent.
struct ManualIP {
  network::IPAddress static_ip;
  network::IPAddress gateway;
  network::IPAddress subnet;
  network::IPAddress dns1;  ///< The first DNS server. 0.0.0.0 for default.
  network::IPAddress dns2;  ///< The second DNS server. 0.0.0.0 for default.
};

#ifdef USE_WIFI_WPA2_EAP
struct EAPAuth {
  std::string identity;  // required for all auth types
  std::string username;
  std::string password;
  const char *ca_cert;  // optionally verify authentication server
  // used for EAP-TLS
  const char *client_cert;
  const char *client_key;
// used for EAP-TTLS
#ifdef USE_ESP32
  esp_eap_ttls_phase2_types ttls_phase_2;
#endif
};
#endif  // USE_WIFI_WPA2_EAP

using bssid_t = std::array<uint8_t, 6>;

/// Initial reserve size for filtered scan results (typical: 1-3 matching networks per SSID)
static constexpr size_t WIFI_SCAN_RESULT_FILTERED_RESERVE = 8;

// Use std::vector for RP2040 (callback-based) and ESP32 (destructive scan API)
// Use FixedVector for ESP8266 and LibreTiny where two-pass exact allocation is possible
#if defined(USE_RP2040) || defined(USE_ESP32)
template<typename T> using wifi_scan_vector_t = std::vector<T>;
#else
template<typename T> using wifi_scan_vector_t = FixedVector<T>;
#endif

/// 20-byte string: 18 chars inline + null, heap for longer. Always null-terminated.
/// Used internally for WiFi SSID/password storage to reduce heap fragmentation.
class CompactString {
 public:
  static constexpr uint8_t MAX_LENGTH = 127;
  static constexpr uint8_t INLINE_CAPACITY = 18;  // 18 chars + null terminator fits in 19 bytes

  CompactString() : length_(0), is_heap_(0) { this->storage_[0] = '\0'; }
  CompactString(const char *str, size_t len);
  CompactString(const CompactString &other);
  CompactString(CompactString &&other) noexcept;
  CompactString &operator=(const CompactString &other);
  CompactString &operator=(CompactString &&other) noexcept;
  ~CompactString();

  const char *data() const { return this->is_heap_ ? this->get_heap_ptr_() : this->storage_; }
  const char *c_str() const { return this->data(); }  // Always null-terminated
  size_t size() const { return this->length_; }
  bool empty() const { return this->length_ == 0; }

  /// Return a StringRef view of this string (zero-copy)
  StringRef ref() const { return StringRef(this->data(), this->size()); }

  bool operator==(const CompactString &other) const;
  bool operator!=(const CompactString &other) const { return !(*this == other); }
  bool operator==(const StringRef &other) const;
  bool operator!=(const StringRef &other) const { return !(*this == other); }
  bool operator==(const char *other) const { return *this == StringRef(other); }
  bool operator!=(const char *other) const { return !(*this == other); }

 protected:
  char *get_heap_ptr_() const {
    char *ptr;
    std::memcpy(&ptr, this->storage_, sizeof(ptr));
    return ptr;
  }
  void set_heap_ptr_(char *ptr) { std::memcpy(this->storage_, &ptr, sizeof(ptr)); }

  // Storage for string data. When is_heap_=0, contains the string directly (null-terminated).
  // When is_heap_=1, first sizeof(char*) bytes contain pointer to heap allocation.
  char storage_[INLINE_CAPACITY + 1];  // 19 bytes: 18 chars + null terminator
  uint8_t length_ : 7;                 // String length (0-127)
  uint8_t is_heap_ : 1;                // 1 if using heap pointer, 0 if using inline storage
  // Total size: 20 bytes (19 bytes storage + 1 byte bitfields)
};

static_assert(sizeof(CompactString) == 20, "CompactString must be exactly 20 bytes");
// CompactString is not trivially copyable (non-trivial destructor/copy for heap case).
// However, its layout has no self-referential pointers: storage_[] contains either inline
// data or an external heap pointer — never a pointer to itself. This is unlike libstdc++
// std::string SSO where _M_p points to _M_local_buf within the same object.
// This property allows memcpy-based permutation sorting where each element ends up in
// exactly one slot (no ownership duplication). These asserts document that layout property.
static_assert(std::is_standard_layout<CompactString>::value, "CompactString must be standard layout");
static_assert(!std::is_polymorphic<CompactString>::value, "CompactString must not have vtable");

class WiFiAP {
  friend class WiFiComponent;
  friend class WiFiScanResult;

 public:
  void set_ssid(const std::string &ssid);
  void set_ssid(const char *ssid);
  void set_ssid(StringRef ssid) { this->ssid_ = CompactString(ssid.c_str(), ssid.size()); }
  void set_bssid(const bssid_t &bssid);
  void clear_bssid();
  void set_password(const std::string &password);
  void set_password(const char *password);
  void set_password(StringRef password) { this->password_ = CompactString(password.c_str(), password.size()); }
#ifdef USE_WIFI_WPA2_EAP
  void set_eap(optional<EAPAuth> eap_auth);
#endif  // USE_WIFI_WPA2_EAP
  void set_channel(uint8_t channel);
  void clear_channel();
  void set_priority(int8_t priority) { priority_ = priority; }
#ifdef USE_WIFI_MANUAL_IP
  void set_manual_ip(optional<ManualIP> manual_ip);
#endif
  void set_hidden(bool hidden);
  StringRef get_ssid() const { return this->ssid_.ref(); }
  StringRef get_password() const { return this->password_.ref(); }
  const bssid_t &get_bssid() const;
  bool has_bssid() const;
#ifdef USE_WIFI_WPA2_EAP
  const optional<EAPAuth> &get_eap() const;
#endif  // USE_WIFI_WPA2_EAP
  uint8_t get_channel() const { return this->channel_; }
  bool has_channel() const { return this->channel_ != 0; }
  int8_t get_priority() const { return priority_; }
#ifdef USE_WIFI_MANUAL_IP
  const optional<ManualIP> &get_manual_ip() const;
#endif
  bool get_hidden() const;

 protected:
  CompactString ssid_;
  CompactString password_;
#ifdef USE_WIFI_WPA2_EAP
  optional<EAPAuth> eap_;
#endif  // USE_WIFI_WPA2_EAP
#ifdef USE_WIFI_MANUAL_IP
  optional<ManualIP> manual_ip_;
#endif
  // Group small types together to minimize padding
  bssid_t bssid_{};     // 6 bytes, all zeros = any/not set
  uint8_t channel_{0};  // 1 byte, 0 = auto/not set
  int8_t priority_{0};  // 1 byte
  bool hidden_{false};  // 1 byte (+ 3 bytes end padding to 4-byte align)
};

class WiFiScanResult {
  friend class WiFiComponent;

 public:
  WiFiScanResult(const bssid_t &bssid, const char *ssid, size_t ssid_len, uint8_t channel, int8_t rssi, bool with_auth,
                 bool is_hidden);

  bool matches(const WiFiAP &config) const;

  bool get_matches() const;
  void set_matches(bool matches);
  const bssid_t &get_bssid() const;
  StringRef get_ssid() const { return this->ssid_.ref(); }
  uint8_t get_channel() const;
  int8_t get_rssi() const;
  bool get_with_auth() const;
  bool get_is_hidden() const;
  int8_t get_priority() const { return priority_; }
  void set_priority(int8_t priority) { priority_ = priority; }

  bool operator==(const WiFiScanResult &rhs) const;

 protected:
  bssid_t bssid_;
  uint8_t channel_;
  int8_t rssi_;
  CompactString ssid_;
  int8_t priority_{0};
  bool matches_{false};
  bool with_auth_;
  bool is_hidden_;
};

struct WiFiSTAPriority {
  bssid_t bssid;
  int8_t priority;
};

enum WiFiPowerSaveMode : uint8_t {
  WIFI_POWER_SAVE_NONE = 0,
  WIFI_POWER_SAVE_LIGHT,
  WIFI_POWER_SAVE_HIGH,
};

enum WifiMinAuthMode : uint8_t {
  WIFI_MIN_AUTH_MODE_WPA = 0,
  WIFI_MIN_AUTH_MODE_WPA2,
  WIFI_MIN_AUTH_MODE_WPA3,
};

#ifdef USE_ESP32
struct IDFWiFiEvent;
#endif

#ifdef USE_LIBRETINY
struct LTWiFiEvent;
#endif

/** Listener interface for WiFi IP state changes.
 *
 * Components can implement this interface to receive IP address updates
 * without the overhead of std::function callbacks.
 *
 * @note Components must call wifi.request_wifi_ip_state_listener() in their
 *       Python to_code() to register for this listener type.
 */
class WiFiIPStateListener {
 public:
  virtual void on_ip_state(const network::IPAddresses &ips, const network::IPAddress &dns1,
                           const network::IPAddress &dns2) = 0;
};

/** Listener interface for WiFi scan results.
 *
 * Components can implement this interface to receive scan results
 * without the overhead of std::function callbacks.
 *
 * @note Components must call wifi.request_wifi_scan_results_listener() in their
 *       Python to_code() to register for this listener type.
 */
class WiFiScanResultsListener {
 public:
  virtual void on_wifi_scan_results(const wifi_scan_vector_t<WiFiScanResult> &results) = 0;
};

/** Listener interface for WiFi connection state changes.
 *
 * Components can implement this interface to receive connection updates
 * without the overhead of std::function callbacks.
 *
 * @note Components must call wifi.request_wifi_connect_state_listener() in their
 *       Python to_code() to register for this listener type.
 */
class WiFiConnectStateListener {
 public:
  virtual void on_wifi_connect_state(StringRef ssid, std::span<const uint8_t, 6> bssid) = 0;
};

/** Listener interface for WiFi power save mode changes.
 *
 * Components can implement this interface to receive power save mode updates
 * without the overhead of std::function callbacks.
 *
 * @note Components must call wifi.request_wifi_power_save_listener() in their
 *       Python to_code() to register for this listener type.
 */
class WiFiPowerSaveListener {
 public:
  virtual void on_wifi_power_save(WiFiPowerSaveMode mode) = 0;
};

/// This component is responsible for managing the ESP WiFi interface.
class WiFiComponent final : public Component {
 public:
  /// Construct a WiFiComponent.
  WiFiComponent();

  void set_sta(const WiFiAP &ap);
  // Returns a copy of the currently selected AP configuration
  WiFiAP get_sta() const;
  void init_sta(size_t count);
  void add_sta(const WiFiAP &ap);
  void clear_sta();

#ifdef USE_WIFI_AP
  /** Setup an Access Point that should be created if no connection to a station can be made.
   *
   * This can also be used without set_sta(). Then the AP will always be active.
   *
   * If both STA and AP are defined, then both will be enabled at startup, but if a connection to a station
   * can be made, the AP will be turned off again.
   */
  void set_ap(const WiFiAP &ap);
  WiFiAP get_ap() { return this->ap_; }
  void set_ap_timeout(uint32_t ap_timeout) { ap_timeout_ = ap_timeout; }
#endif  // USE_WIFI_AP

  void enable();
  void disable();
  bool is_disabled();
  void start_scanning();
  void check_scanning_finished();
  void start_connecting(const WiFiAP &ap);
  // Backward compatibility overload - ignores 'two' parameter
  void start_connecting(const WiFiAP &ap, bool /* two */) { this->start_connecting(ap); }

  void check_connecting_finished(uint32_t now);

  void retry_connect();

  void set_reboot_timeout(uint32_t reboot_timeout);

  bool is_connected() const { return this->connected_; }

  void set_power_save_mode(WiFiPowerSaveMode power_save);
  void set_min_auth_mode(WifiMinAuthMode min_auth_mode) { min_auth_mode_ = min_auth_mode; }
  void set_output_power(float output_power) { output_power_ = output_power; }
#if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
  void set_band_mode(wifi_band_mode_t band_mode) { this->band_mode_ = band_mode; }
#endif

  void set_passive_scan(bool passive);

  void save_wifi_sta(const std::string &ssid, const std::string &password);
  void save_wifi_sta(const char *ssid, const char *password);
  void save_wifi_sta(StringRef ssid, StringRef password) { this->save_wifi_sta(ssid.c_str(), password.c_str()); }

  // ========== INTERNAL METHODS ==========
  // (In most use cases you won't need these)
  /// Setup WiFi interface.
  void setup() override;
  void start();
  void dump_config() override;
  void restart_adapter();
  /// WIFI setup_priority.
  float get_setup_priority() const override;
  /// Reconnect WiFi if required.
  void loop() override;

  bool has_sta() const { return !this->sta_.empty(); }
  bool has_ap() const { return this->has_ap_; }
  bool is_ap_active() const { return this->ap_started_; }

#ifdef USE_WIFI_11KV_SUPPORT
  void set_btm(bool btm);
  void set_rrm(bool rrm);
#endif

  network::IPAddress get_dns_address(int num);
  network::IPAddresses get_ip_addresses();
  const char *get_use_address() const { return this->use_address_; }
  void set_use_address(const char *use_address) { this->use_address_ = use_address; }

  const wifi_scan_vector_t<WiFiScanResult> &get_scan_result() const { return scan_result_; }

  network::IPAddress wifi_soft_ap_ip();

  bool has_sta_priority(const bssid_t &bssid) {
    for (auto &it : this->sta_priorities_) {
      if (it.bssid == bssid)
        return true;
    }
    return false;
  }
  int8_t get_sta_priority(const bssid_t bssid) {
    for (auto &it : this->sta_priorities_) {
      if (it.bssid == bssid)
        return it.priority;
    }
    return 0;
  }
  void set_sta_priority(bssid_t bssid, int8_t priority);

  network::IPAddresses wifi_sta_ip_addresses();
  // Remove before 2026.9.0
  ESPDEPRECATED("Use wifi_ssid_to() instead. Removed in 2026.9.0", "2026.3.0")
  std::string wifi_ssid();
  /// Write SSID to buffer without heap allocation.
  /// Returns pointer to buffer, or empty string if not connected.
  const char *wifi_ssid_to(std::span<char, SSID_BUFFER_SIZE> buffer);
  bssid_t wifi_bssid();

  int8_t wifi_rssi();

  void set_enable_on_boot(bool enable_on_boot) { this->enable_on_boot_ = enable_on_boot; }
  void set_keep_scan_results(bool keep_scan_results) { this->keep_scan_results_ = keep_scan_results; }
  void set_post_connect_roaming(bool enabled) { this->post_connect_roaming_ = enabled; }

#ifdef USE_WIFI_CONNECT_TRIGGER
  Trigger<> *get_connect_trigger() { return &this->connect_trigger_; }
#endif
#ifdef USE_WIFI_DISCONNECT_TRIGGER
  Trigger<> *get_disconnect_trigger() { return &this->disconnect_trigger_; }
#endif

  int32_t get_wifi_channel();

#ifdef USE_WIFI_IP_STATE_LISTENERS
  /** Add a listener for IP state changes.
   * Listener receives: IP addresses, DNS address 1, DNS address 2
   */
  void add_ip_state_listener(WiFiIPStateListener *listener) { this->ip_state_listeners_.push_back(listener); }
#endif  // USE_WIFI_IP_STATE_LISTENERS
#ifdef USE_WIFI_SCAN_RESULTS_LISTENERS
  /// Add a listener for WiFi scan results
  void add_scan_results_listener(WiFiScanResultsListener *listener) {
    this->scan_results_listeners_.push_back(listener);
  }
#endif  // USE_WIFI_SCAN_RESULTS_LISTENERS
#ifdef USE_WIFI_CONNECT_STATE_LISTENERS
  /** Add a listener for WiFi connection state changes.
   * Listener receives: SSID, BSSID
   */
  void add_connect_state_listener(WiFiConnectStateListener *listener) {
    this->connect_state_listeners_.push_back(listener);
  }
#endif  // USE_WIFI_CONNECT_STATE_LISTENERS
#ifdef USE_WIFI_POWER_SAVE_LISTENERS
  /** Add a listener for WiFi power save mode changes.
   * Listener receives: WiFiPowerSaveMode
   */
  void add_power_save_listener(WiFiPowerSaveListener *listener) { this->power_save_listeners_.push_back(listener); }
#endif  // USE_WIFI_POWER_SAVE_LISTENERS

#ifdef USE_WIFI_RUNTIME_POWER_SAVE
  /** Request high-performance mode (no power saving) for improved WiFi latency.
   *
   * Components that need maximum WiFi performance (e.g., audio streaming, large data transfers)
   * can call this method to temporarily disable WiFi power saving. Multiple components can
   * request high performance simultaneously using a counting semaphore.
   *
   * Power saving will be restored to the YAML-configured mode when all components have
   * called release_high_performance().
   *
   * Note: Only supported on ESP32.
   *
   * @return true if request was satisfied (high-performance mode active or already configured),
   *         false if operation failed (semaphore error)
   */
  bool request_high_performance();

  /** Release a high-performance mode request.
   *
   * Should be called when a component no longer needs maximum WiFi latency.
   * When all requests are released (semaphore count reaches zero), WiFi power saving
   * is restored to the YAML-configured mode.
   *
   * Note: Only supported on ESP32.
   *
   * @return true if release was successful (or already in high-performance config),
   *         false if operation failed (semaphore error)
   */
  bool release_high_performance();
#endif  // USE_WIFI_RUNTIME_POWER_SAVE

 protected:
#ifdef USE_WIFI_AP
  void setup_ap_config_();
#endif  // USE_WIFI_AP

  void print_connect_params_();
  WiFiAP build_params_for_current_phase_();

  /// Determine next retry phase based on current state and failure conditions
  WiFiRetryPhase determine_next_phase_();
  /// Transition to a new retry phase with logging
  /// Returns true if a scan was started (caller should wait), false otherwise
  bool transition_to_phase_(WiFiRetryPhase new_phase);
  /// Check if we need valid scan results for the current phase but don't have any
  /// Returns true if the phase requires scan results but they're missing or don't match
  bool needs_scan_results_() const;
  /// Check if we went through EXPLICIT_HIDDEN phase (first network is marked hidden)
  /// Used in RETRY_HIDDEN to determine whether to skip explicitly hidden networks
  bool went_through_explicit_hidden_phase_() const;
  /// Find the index of the first non-hidden network
  /// Returns where EXPLICIT_HIDDEN phase would have stopped, or -1 if all networks are hidden
  int8_t find_first_non_hidden_index_() const;
  /// Check if an SSID was seen in the most recent scan results
  /// Used to skip hidden mode for SSIDs we know are visible
  bool ssid_was_seen_in_scan_(const CompactString &ssid) const;
  /// Check if full scan results are needed (captive portal active, improv, listeners)
  bool needs_full_scan_results_() const;
  /// Check if network matches any configured network (for scan result filtering)
  /// Matches by SSID when configured, or by BSSID for BSSID-only configs
  bool matches_configured_network_(const char *ssid, const uint8_t *bssid) const;
  /// Log a discarded scan result at VERBOSE level (skipped during roaming scans to avoid log overflow)
  void log_discarded_scan_result_(const char *ssid, const uint8_t *bssid, int8_t rssi, uint8_t channel);
  /// Find next SSID that wasn't in scan results (might be hidden)
  /// Returns index of next potentially hidden SSID, or -1 if none found
  /// @param start_index Start searching from index after this (-1 to start from beginning)
  int8_t find_next_hidden_sta_(int8_t start_index);
  /// Log failed connection and decrease BSSID priority to avoid repeated attempts
  void log_and_adjust_priority_for_failed_connect_();
  /// Clear all BSSID priority penalties after successful connection (stale after disconnect)
  void clear_all_bssid_priorities_();
  /// Clear BSSID priority tracking if all priorities are at minimum (saves memory)
  void clear_priorities_if_all_min_();
  /// Advance to next target (AP/SSID) within current phase, or increment retry counter
  /// Called when staying in the same phase after a failed connection attempt
  void advance_to_next_target_or_increment_retry_();
  /// Start initial connection - either scan or connect directly to hidden networks
  void start_initial_connection_();
  const WiFiAP *get_selected_sta_() const {
    if (this->selected_sta_index_ >= 0 && static_cast<size_t>(this->selected_sta_index_) < this->sta_.size()) {
      return &this->sta_[this->selected_sta_index_];
    }
    return nullptr;
  }

  void reset_selected_ap_to_first_if_invalid_() {
    if (this->selected_sta_index_ < 0 || static_cast<size_t>(this->selected_sta_index_) >= this->sta_.size()) {
      this->selected_sta_index_ = this->sta_.empty() ? -1 : 0;
    }
  }

  bool all_networks_hidden_() const {
    if (this->sta_.empty())
      return false;
    for (const auto &ap : this->sta_) {
      if (!ap.get_hidden())
        return false;
    }
    return true;
  }

  void connect_soon_();

  void wifi_loop_();
#ifdef USE_ESP8266
  void process_pending_callbacks_();
#endif
  bool wifi_mode_(optional<bool> sta, optional<bool> ap);
  bool wifi_sta_pre_setup_();
  bool wifi_apply_output_power_(float output_power);
  bool wifi_apply_power_save_();
#if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
  bool wifi_apply_band_mode_();
#endif
  bool wifi_sta_ip_config_(const optional<ManualIP> &manual_ip);
  bool wifi_apply_hostname_();
  bool wifi_sta_connect_(const WiFiAP &ap);
  void wifi_pre_setup_();
  WiFiSTAConnectStatus wifi_sta_connect_status_() const;
  bool is_connected_() const {
    return this->state_ == WIFI_COMPONENT_STATE_STA_CONNECTED &&
           this->wifi_sta_connect_status_() == WiFiSTAConnectStatus::CONNECTED && !this->error_from_callback_;
  }
  void update_connected_state_() { this->connected_ = this->is_connected_(); }
  bool wifi_scan_start_(bool passive);

#ifdef USE_WIFI_AP
  bool wifi_ap_ip_config_(const optional<ManualIP> &manual_ip);
  bool wifi_start_ap_(const WiFiAP &ap);
#endif  // USE_WIFI_AP

  bool wifi_disconnect_();

  network::IPAddress wifi_subnet_mask_();
  network::IPAddress wifi_gateway_ip_();
  network::IPAddress wifi_dns_ip_(int num);

  bool is_captive_portal_active_();
  bool is_esp32_improv_active_();

#ifdef USE_WIFI_FAST_CONNECT
  bool load_fast_connect_settings_(WiFiAP &params);
  void save_fast_connect_settings_();
#endif

  // Post-connect roaming methods
  void check_roaming_(uint32_t now);
  void process_roaming_scan_();
  void clear_roaming_state_();

  /// Free scan results memory unless a component needs them
  void release_scan_results_();

#ifdef USE_WIFI_CONNECT_STATE_LISTENERS
  /// Notify connect state listeners (called after state machine reaches STA_CONNECTED)
  void notify_connect_state_listeners_();
  /// Notify connect state listeners of disconnection
  void notify_disconnect_state_listeners_();
#endif
#ifdef USE_WIFI_IP_STATE_LISTENERS
  /// Notify IP state listeners with current addresses
  void notify_ip_state_listeners_();
#endif
#ifdef USE_WIFI_SCAN_RESULTS_LISTENERS
  /// Notify scan results listeners with current scan results
  void notify_scan_results_listeners_();
#endif

#ifdef USE_ESP8266
  static void wifi_event_callback(System_Event_t *event);
  void wifi_scan_done_callback_(void *arg, STATUS status);
  static void s_wifi_scan_done_callback(void *arg, STATUS status);
#endif

#ifdef USE_ESP32
  void wifi_process_event_(IDFWiFiEvent *data);
  friend void event_handler(void *arg, esp_event_base_t event_base, int32_t event_id, void *event_data);
#endif

#ifdef USE_RP2040
  static int s_wifi_scan_result(void *env, const cyw43_ev_scan_result_t *result);
  void wifi_scan_result(void *env, const cyw43_ev_scan_result_t *result);
#endif

#ifdef USE_LIBRETINY
  void wifi_event_callback_(arduino_event_id_t event, arduino_event_info_t info);
  void wifi_process_event_(LTWiFiEvent *event);
  void wifi_scan_done_callback_();
#endif

  // Large/pointer-aligned members first
  FixedVector<WiFiAP> sta_;
  std::vector<WiFiSTAPriority> sta_priorities_;
  wifi_scan_vector_t<WiFiScanResult> scan_result_;
#ifdef USE_WIFI_AP
  WiFiAP ap_;
#endif
#ifdef USE_WIFI_IP_STATE_LISTENERS
  StaticVector<WiFiIPStateListener *, ESPHOME_WIFI_IP_STATE_LISTENERS> ip_state_listeners_;
#endif
#ifdef USE_WIFI_SCAN_RESULTS_LISTENERS
  StaticVector<WiFiScanResultsListener *, ESPHOME_WIFI_SCAN_RESULTS_LISTENERS> scan_results_listeners_;
#endif
#ifdef USE_WIFI_CONNECT_STATE_LISTENERS
  StaticVector<WiFiConnectStateListener *, ESPHOME_WIFI_CONNECT_STATE_LISTENERS> connect_state_listeners_;
#endif
#ifdef USE_WIFI_POWER_SAVE_LISTENERS
  StaticVector<WiFiPowerSaveListener *, ESPHOME_WIFI_POWER_SAVE_LISTENERS> power_save_listeners_;
#endif
  ESPPreferenceObject pref_;
#ifdef USE_WIFI_FAST_CONNECT
  ESPPreferenceObject fast_connect_pref_;
#endif
#ifdef USE_WIFI_CONNECT_TRIGGER
  Trigger<> connect_trigger_;
#endif
#ifdef USE_WIFI_DISCONNECT_TRIGGER
  Trigger<> disconnect_trigger_;
#endif
#if defined(USE_ESP32) && defined(USE_WIFI_RUNTIME_POWER_SAVE)
  SemaphoreHandle_t high_performance_semaphore_{nullptr};
#endif

  static constexpr uint8_t FIRST_5GHZ_CHANNEL = 36;

  // Post-connect roaming constants
  static constexpr uint32_t ROAMING_CHECK_INTERVAL = 5 * 60 * 1000;  // 5 minutes
  static constexpr int8_t ROAMING_MIN_IMPROVEMENT = 10;              // dB
  static constexpr int8_t ROAMING_GOOD_RSSI = -49;                   // Skip scan if signal is excellent
  static constexpr uint8_t ROAMING_MAX_ATTEMPTS = 3;
  // Grace period after roaming scan completes. If WiFi disconnects within this
  // window (e.g., ESP8266 Beacon Timeout caused by going off-channel during scan),
  // the disconnect is treated as roaming-related and the attempts counter is preserved.
  static constexpr uint32_t ROAMING_SCAN_GRACE_PERIOD = 30 * 1000;  // 30 seconds

  // 4-byte members
  float output_power_{NAN};
  uint32_t action_started_;
  uint32_t last_connected_{0};
  uint32_t reboot_timeout_{};
  uint32_t roaming_last_check_{0};
  uint32_t roaming_scan_end_{0};  // Timestamp when last roaming scan completed
#ifdef USE_WIFI_AP
  uint32_t ap_timeout_{};
#endif

  // 1-byte enums and integers
  WiFiComponentState state_{WIFI_COMPONENT_STATE_OFF};
  WiFiPowerSaveMode power_save_{WIFI_POWER_SAVE_NONE};
#if defined(USE_ESP32) && defined(SOC_WIFI_SUPPORT_5G)
  wifi_band_mode_t band_mode_{WIFI_BAND_MODE_AUTO};
#endif
  WifiMinAuthMode min_auth_mode_{WIFI_MIN_AUTH_MODE_WPA2};
  WiFiRetryPhase retry_phase_{WiFiRetryPhase::INITIAL_CONNECT};
  uint8_t num_retried_{0};
  // Index into sta_ array for the currently selected AP configuration (-1 = none selected)
  // Used to access password, manual_ip, priority, EAP settings, and hidden flag
  // int8_t limits to 127 APs (enforced in __init__.py via MAX_WIFI_NETWORKS)
  int8_t selected_sta_index_{-1};
  uint8_t roaming_attempts_{0};
#if USE_NETWORK_IPV6
  uint8_t num_ipv6_addresses_{0};
#endif /* USE_NETWORK_IPV6 */
  bool error_from_callback_{false};
#if defined(USE_ESP8266) || defined(USE_LIBRETINY)
  // Platform-specific STA state enum, defined in platform cpp file.
  // On ESP8266, written from SDK system context (wifi_event_callback) —
  // uint8_t writes are atomic on Xtensa LX106 so no synchronization is needed.
  uint8_t sta_state_{0};
#endif
  RetryHiddenMode retry_hidden_mode_{RetryHiddenMode::BLIND_RETRY};
  RoamingState roaming_state_{RoamingState::IDLE};
  bssid_t roaming_target_bssid_{};  // BSSID of the AP we're trying to roam to
#if defined(USE_ESP32) && defined(USE_WIFI_RUNTIME_POWER_SAVE)
  WiFiPowerSaveMode configured_power_save_{WIFI_POWER_SAVE_NONE};
#endif

  // Bools and bitfields
  // Pending listener callbacks deferred from platform callbacks to main loop.
  struct {
#ifdef USE_WIFI_CONNECT_STATE_LISTENERS
    // Deferred until state machine reaches STA_CONNECTED so wifi.connected
    // condition returns true in listener automations.
    bool connect_state : 1;
#ifdef USE_ESP8266
    // ESP8266: also defer disconnect notification to main loop
    bool disconnect : 1;
#endif
#endif
#if defined(USE_ESP8266) && defined(USE_WIFI_IP_STATE_LISTENERS)
    bool got_ip : 1;
#endif
#if defined(USE_ESP8266) && defined(USE_WIFI_SCAN_RESULTS_LISTENERS)
    bool scan_complete : 1;
#endif
  } pending_{};
  bool has_ap_{false};
#if defined(USE_WIFI_CONNECT_TRIGGER) || defined(USE_WIFI_DISCONNECT_TRIGGER)
  bool handled_connected_state_{false};
#endif
  bool scan_done_{false};
  bool ap_setup_{false};
  bool ap_started_{false};
  bool passive_scan_{false};
  bool has_saved_wifi_settings_{false};
#ifdef USE_WIFI_11KV_SUPPORT
  bool btm_{false};
  bool rrm_{false};
#endif
  bool enable_on_boot_{true};
  bool got_ipv4_address_{false};
  bool keep_scan_results_{false};
  bool has_completed_scan_after_captive_portal_start_{
      false};  // Tracks if we've completed a scan after captive portal started
  bool skip_cooldown_next_cycle_{false};
  bool connected_{false};
  bool post_connect_roaming_{true};  // Enabled by default
#if defined(USE_ESP32) && defined(USE_WIFI_RUNTIME_POWER_SAVE)
  bool is_high_performance_mode_{false};
#endif

#ifdef USE_ESP32
  // Lock-free SPSC queue for WiFi events from ESP-IDF event handler.
  // 17 slots = 16 usable (ring buffer reserves one slot). WiFi events are rare.
  // Placed at end of class to avoid padding between smaller fields.
  LockFreeQueue<IDFWiFiEvent, 17> event_queue_;
#endif

 private:
  // Stores a pointer to a string literal (static storage duration).
  // ONLY set from Python-generated code with string literals - never dynamic strings.
  const char *use_address_{""};
};

extern WiFiComponent *global_wifi_component;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)

}  // namespace esphome::wifi
#endif