#include "wifi/wifi.h"
#include <cstring>
#include <stdexcept>

#include "esp_event_base.h"
#include "esp_netif.h"
#include "esp_netif_ip_addr.h"
#include "esp_netif_types.h"
#include "esp_wifi.h"
#include "esp_wifi_types.h"

#include <util/inplace_function.h>


namespace {


esp_netif_t* gSoftApNetif;
esp_netif_t* gStationNetif;

inplace_function<void(std::array<char, 18>, uint8_t)> gAPConnectCallback =
    [](auto...) {};
inplace_function<void(std::array<char, 18>, uint8_t)> gAPDisconnectCallback =
    [](auto...) {};

inplace_function<void()>                     gStationStartCallback      = [] {};
inplace_function<void()>                     gStationDisconnectCallback = [] {};
inplace_function<void(std::array<char, 17>)> gStationGotIpCallback =
    [](auto...) {};


void wifi_event_handler(void*, esp_event_base_t event_base, int32_t event_id,
                        void* event_data) {
    if (event_base == WIFI_EVENT) {
        if (event_id == WIFI_EVENT_STA_START) {
            gStationStartCallback();
        } else if (event_id == WIFI_EVENT_STA_DISCONNECTED) {
            gStationDisconnectCallback();
        } else if (event_id == WIFI_EVENT_AP_STACONNECTED) {
            auto disconnectEvent =
                reinterpret_cast<wifi_event_ap_stadisconnected_t*>(event_data);

            std::array<char, 18> macStr = {0};
            std::snprintf(macStr.data(), macStr.size(),
                          "%02x:%02x:%02x:%02x:%02x:%02x",
                          disconnectEvent->mac[0], disconnectEvent->mac[1],
                          disconnectEvent->mac[2], disconnectEvent->mac[3],
                          disconnectEvent->mac[4], disconnectEvent->mac[5]);

            gAPConnectCallback(macStr, disconnectEvent->aid);
        } else if (event_id == WIFI_EVENT_AP_STADISCONNECTED) {
            auto disconnectEvent =
                reinterpret_cast<wifi_event_ap_stadisconnected_t*>(event_data);

            std::array<char, 18> macStr = {0};
            std::snprintf(macStr.data(), macStr.size(),
                          "%02x:%02x:%02x:%02x:%02x:%02x",
                          disconnectEvent->mac[0], disconnectEvent->mac[1],
                          disconnectEvent->mac[2], disconnectEvent->mac[3],
                          disconnectEvent->mac[4], disconnectEvent->mac[5]);

            gAPDisconnectCallback(macStr, disconnectEvent->aid);
        }
    } else if (event_base == IP_EVENT) {
        if (event_id == IP_EVENT_STA_GOT_IP) {
            auto event = reinterpret_cast<ip_event_got_ip_t*>(event_data);

            auto ipAddr = &event->ip_info.ip;

            std::array<char, 17> ipStr = {0};
            std::snprintf(ipStr.data(), ipStr.size(), "%d.%d.%d.%d",
                          esp_ip4_addr1_16(ipAddr), esp_ip4_addr2_16(ipAddr),
                          esp_ip4_addr3_16(ipAddr), esp_ip4_addr4_16(ipAddr));

            gStationGotIpCallback(ipStr);
        }
    }
}


} // namespace


namespace wifi {


void init() {
    if (esp_netif_init() != ESP_OK)
        throw std::runtime_error("Failed to initialize netif");

    if (esp_event_loop_create_default() != ESP_OK)
        throw std::runtime_error("Failed to create event loop");

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    if (esp_wifi_init(&cfg) != ESP_OK)
        throw std::runtime_error("Failed to initialize wifi");

    if (esp_event_handler_instance_register(
            ESP_EVENT_ANY_BASE, ESP_EVENT_ANY_ID, &wifi_event_handler, NULL,
            NULL) != ESP_OK)
        throw std::runtime_error("Failed to register wifi event handler");
}

void deinit() {
    if (esp_wifi_deinit() != ESP_OK)
        throw std::runtime_error("Failed to deinitialize wifi");

    if (esp_event_loop_delete_default() != ESP_OK)
        throw std::runtime_error("Failed to delete event loop");

    // Apparently, this is not implemented in the esp idf yet
    // esp_netif_deinit();
}

void set_mode(Mode mode) {
    wifi_mode_t esp_mode = WIFI_MODE_NULL;

    switch (mode) {
    case Mode::station:
        esp_mode = WIFI_MODE_STA;
        break;
    case Mode::soft_ap:
        esp_mode = WIFI_MODE_AP;
        break;
        //    case Mode::station_and_soft_ap:
        //        esp_mode = WIFI_MODE_APSTA;
        //        break;
    }

    if (esp_wifi_set_mode(esp_mode) != ESP_OK)
        throw std::runtime_error("Failed to set wifi mode");
}

void configure_soft_ap(std::string_view ssid, std::string_view password,
                       soft_ap_settings_t settings) {

    // Create network interface

    if (gSoftApNetif != nullptr) esp_netif_destroy_default_wifi(gSoftApNetif);
    gSoftApNetif = esp_netif_create_default_wifi_ap();

    // Configure wifi

    wifi_config_t wifi_config = {
        .ap =
            {
                .ssid_len = static_cast<uint8_t>(ssid.size()),
                .channel  = settings.channel,
                .authmode =
                    password.size() != 0 ? WIFI_AUTH_WPA3_PSK : WIFI_AUTH_OPEN,
                .max_connection = settings.max_connections,
                .pmf_cfg =
                    {
                        .required = true,
                    },
                .sae_pwe_h2e = WPA3_SAE_PWE_BOTH,
            },
    };
    std::copy(ssid.begin(), ssid.end(), wifi_config.ap.ssid);
    std::copy(password.begin(), password.end(), wifi_config.ap.password);

    if (esp_wifi_set_config(WIFI_IF_AP, &wifi_config) != ESP_OK)
        throw std::runtime_error("Failed to set wifi config");

    // Register event handlers

    gAPConnectCallback    = settings.connected;
    gAPDisconnectCallback = settings.disconnected;
}

void configure_station(std::string_view ssid, std::string_view password,
                       station_settings_t settings) {

    // Create network interface

    if (gStationNetif != nullptr) esp_netif_destroy_default_wifi(gStationNetif);
    gStationNetif = esp_netif_create_default_wifi_sta();


    // Configure wifi

    // TODO: Are there really no other settings necessary?
    wifi_config_t wifi_config = {};
    std::copy(ssid.begin(), ssid.end(), wifi_config.sta.ssid);
    std::copy(password.begin(), password.end(), wifi_config.sta.password);

    if (esp_wifi_set_config(WIFI_IF_STA, &wifi_config) != ESP_OK)
        throw std::runtime_error("Failed to configure wifi station");

    // Set event handlers

    gStationStartCallback      = settings.stationStarted;
    gStationDisconnectCallback = settings.disconnected;
    gStationGotIpCallback      = settings.gotIp;
}

void clear_callbacks() {
    gAPConnectCallback         = [](auto...) {};
    gAPDisconnectCallback      = [](auto...) {};
    gStationStartCallback      = [] {};
    gStationGotIpCallback      = [](auto...) {};
    gStationDisconnectCallback = [] {};
}

void station_connect() {
    if (esp_wifi_connect() != ESP_OK)
        throw std::runtime_error("Failed to connect to wifi");
}

void station_disconnect() {
    if (esp_wifi_disconnect() != ESP_OK)
        throw std::runtime_error("Failed to disconnect from wifi");
}

void start() {
    if (esp_wifi_start() != ESP_OK)
        throw std::runtime_error("Failed to start wifi");
}

void stop() {
    if (esp_wifi_stop() != ESP_OK)
        throw std::runtime_error("Failed to stop wifi");
}

std::span<scanned_ap_t> scan(std::span<scanned_ap_t> memory) {
    uint16_t         number = memory.size();
    wifi_ap_record_t ap_info[number];

    esp_err_t err;

    if ((err = esp_wifi_scan_start(NULL, true)) != ESP_OK) {
        throw std::runtime_error("Failed to start scan");
    }

    if (esp_wifi_scan_get_ap_records(&number, ap_info) != ESP_OK)
        throw std::runtime_error("Failed to get wifi ap records");

    std::transform(&ap_info[0], &ap_info[0] + number, memory.begin(),
                   [](const wifi_ap_record_t& record) {
                       scanned_ap_t result;
                       std::copy(&record.ssid[0], &record.ssid[0] + 32,
                                 result.ssid.begin());
                       result.rssi = record.rssi;
                       return result;
                   });

    return std::span{memory.begin(), number};
}


} // namespace wifi