/*
 *
 *    Copyright (c) 2018 Nest Labs, Inc.
 *    All rights reserved.
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

/**
 *    @file
 *          General utility methods for the ESP32 platform.
 */

#include <Weave/DeviceLayer/internal/WeaveDeviceLayerInternal.h>

#include <Weave/DeviceLayer/ESP32/ESP32Utils.h>

#include "esp_event.h"
#include "esp_wifi.h"

using namespace ::nl::Weave::DeviceLayer::Internal;
using namespace ::nl::Weave::Profiles::NetworkProvisioning;

WEAVE_ERROR ESP32Utils::IsAPEnabled(bool & apEnabled)
{
    WEAVE_ERROR err;
    wifi_mode_t curWiFiMode;

    err = esp_wifi_get_mode(&curWiFiMode);
    if (err != ESP_OK)
    {
        WeaveLogError(DeviceLayer, "esp_wifi_get_mode() failed: %s", nl::ErrorStr(err));
        return err;
    }

    apEnabled = (curWiFiMode == WIFI_MODE_AP || curWiFiMode == WIFI_MODE_APSTA);

    return WEAVE_NO_ERROR;
}

bool ESP32Utils::IsStationProvisioned(void)
{
    wifi_config_t stationConfig;
    return (esp_wifi_get_config(ESP_IF_WIFI_STA, &stationConfig) == ERR_OK && stationConfig.sta.ssid[0] != 0);
}

WEAVE_ERROR ESP32Utils::IsStationConnected(bool & connected)
{
    wifi_ap_record_t apInfo;
    connected = (esp_wifi_sta_get_ap_info(&apInfo) == ESP_OK);
    return WEAVE_NO_ERROR;
}

WEAVE_ERROR ESP32Utils::StartWiFiLayer(void)
{
    WEAVE_ERROR err;
    int8_t ignored;
    bool wifiStarted;

    // There appears to be no direct way to ask the ESP WiFi layer if esp_wifi_start()
    // has been called.  So use the ESP_ERR_WIFI_NOT_STARTED error returned by
    // esp_wifi_get_max_tx_power() to detect this.
    err = esp_wifi_get_max_tx_power(&ignored);
    switch (err)
    {
    case ESP_OK:
        wifiStarted = true;
        break;
    case ESP_ERR_WIFI_NOT_STARTED:
        wifiStarted = false;
        err = ESP_OK;
        break;
    default:
        ExitNow();
    }

    if (!wifiStarted)
    {
        WeaveLogProgress(DeviceLayer, "Starting ESP WiFi layer");

        err = esp_wifi_start();
        if (err != ESP_OK)
        {
            WeaveLogError(DeviceLayer, "esp_wifi_start() failed: %s", nl::ErrorStr(err));
        }
    }

exit:
    return err;
}

WEAVE_ERROR ESP32Utils::EnableStationMode(void)
{
    WEAVE_ERROR err;
    wifi_mode_t curWiFiMode;

    // Get the current ESP WiFI mode.
    err = esp_wifi_get_mode(&curWiFiMode);
    if (err != ESP_OK)
    {
        WeaveLogError(DeviceLayer, "esp_wifi_get_mode() failed: %s", nl::ErrorStr(err));
    }
    SuccessOrExit(err);

    // If station mode is not already enabled (implying the current mode is WIFI_MODE_AP), change
    // the mode to WIFI_MODE_APSTA.
    if (curWiFiMode == WIFI_MODE_AP)
    {
        WeaveLogProgress(DeviceLayer, "Changing ESP WiFi mode: %s -> %s", WiFiModeToStr(WIFI_MODE_AP), WiFiModeToStr(WIFI_MODE_APSTA));

        err = esp_wifi_set_mode(WIFI_MODE_APSTA);
        if (err != ESP_OK)
        {
            WeaveLogError(DeviceLayer, "esp_wifi_set_mode() failed: %s", nl::ErrorStr(err));
        }
        SuccessOrExit(err);
    }

exit:
    return err;
}

WEAVE_ERROR ESP32Utils::SetAPMode(bool enabled)
{
    WEAVE_ERROR err;
    wifi_mode_t curWiFiMode, targetWiFiMode;

    targetWiFiMode = (enabled) ? WIFI_MODE_APSTA : WIFI_MODE_STA;

    // Get the current ESP WiFI mode.
    err = esp_wifi_get_mode(&curWiFiMode);
    if (err != ESP_OK)
    {
        WeaveLogError(DeviceLayer, "esp_wifi_get_mode() failed: %s", nl::ErrorStr(err));
    }
    SuccessOrExit(err);

    // If station mode is not already enabled (implying the current mode is WIFI_MODE_AP), change
    // the mode to WIFI_MODE_APSTA.
    if (true /* curWiFiMode != targetWiFiMode */)
    {
        WeaveLogProgress(DeviceLayer, "Changing ESP WiFi mode: %s -> %s", WiFiModeToStr(curWiFiMode), WiFiModeToStr(targetWiFiMode));

        err = esp_wifi_set_mode(targetWiFiMode);
        if (err != ESP_OK)
        {
            WeaveLogError(DeviceLayer, "esp_wifi_set_mode() failed: %s", nl::ErrorStr(err));
        }
        SuccessOrExit(err);
    }

exit:
    return err;
}

WiFiSecurityType ESP32Utils::WiFiAuthModeToWeaveWiFiSecurityType(wifi_auth_mode_t authMode)
{
    switch (authMode)
    {
    case WIFI_AUTH_OPEN:
        return kWiFiSecurityType_None;
    case WIFI_AUTH_WEP:
        return kWiFiSecurityType_WEP;
    case WIFI_AUTH_WPA_PSK:
        return kWiFiSecurityType_WPAPersonal;
    case WIFI_AUTH_WPA2_PSK:
        return kWiFiSecurityType_WPA2Personal;
    case WIFI_AUTH_WPA_WPA2_PSK:
        return kWiFiSecurityType_WPA2MixedPersonal;
    case WIFI_AUTH_WPA2_ENTERPRISE:
        return kWiFiSecurityType_WPA2Enterprise;
    default:
        return kWiFiSecurityType_NotSpecified;
    }
}

int ESP32Utils::OrderScanResultsByRSSI(const void * _res1, const void * _res2)
{
    const wifi_ap_record_t * res1 = (const wifi_ap_record_t *) _res1;
    const wifi_ap_record_t * res2 = (const wifi_ap_record_t *) _res2;

    if (res1->rssi > res2->rssi)
    {
        return -1;
    }
    if (res1->rssi < res2->rssi)
    {
        return 1;
    }
    return 0;
}

const char * ESP32Utils::WiFiModeToStr(wifi_mode_t wifiMode)
{
    switch (wifiMode)
    {
    case WIFI_MODE_NULL:
        return "NULL";
    case WIFI_MODE_STA:
        return "STA";
    case WIFI_MODE_AP:
        return "AP";
    case WIFI_MODE_APSTA:
        return "STA+AP";
    default:
        return "(unknown)";
    }
}

struct netif * ESP32Utils::GetStationNetif(void)
{
    return GetNetif(TCPIP_ADAPTER_IF_STA);
}

struct netif * ESP32Utils::GetNetif(tcpip_adapter_if_t intfId)
{
    struct netif * netif;
    return (tcpip_adapter_get_netif(intfId, (void **)&netif) == ESP_OK) ? netif : NULL;
}

bool ESP32Utils::IsInterfaceUp(tcpip_adapter_if_t intfId)
{
    struct netif * netif = GetNetif(intfId);
    return netif != NULL && netif_is_up(netif);
}

const char * ESP32Utils::InterfaceIdToName(tcpip_adapter_if_t intfId)
{
    switch (intfId)
    {
    case TCPIP_ADAPTER_IF_STA:
        return "WiFi station";
    case TCPIP_ADAPTER_IF_AP:
        return "WiFi AP";
    case TCPIP_ADAPTER_IF_ETH:
        return "Ethernet";
    default:
        return "(unknown)";
    }
}

bool ESP32Utils::HasIPv6LinkLocalAddress(tcpip_adapter_if_t intfId)
{
    ip6_addr_t unused;
    return tcpip_adapter_get_ip6_linklocal(intfId, &unused) == ESP_OK;
}