/*
 ESP8266WiFiGeneric.cpp - WiFi library for esp8266

 Copyright (c) 2014 Ivan Grokhotkov. All rights reserved.
 This file is part of the esp8266 core for Arduino environment.

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 Reworked on 28 Dec 2015 by Markus Sattler

 */

#include "WiFi.h"
#include "WiFiGeneric.h"

extern "C" {
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <string.h>

#include <esp_err.h>
#include <esp_wifi.h>
#include <esp_event_loop.h>
#include "lwip/ip_addr.h"
#include "lwip/opt.h"
#include "lwip/err.h"
#include "lwip/dns.h"
#include "esp_ipc.h"


} //extern "C"

#include "esp32-hal-log.h"

#undef min
#undef max
#include <vector>

void tcpipInit(){
    static bool initialized = false;
    if(!initialized){
        initialized = true;
        tcpip_adapter_init();
        esp_event_loop_init(&WiFiGenericClass::_eventCallback, NULL);
    }
}

static bool wifiLowLevelInit(){
    static bool lowLevelInitDone = false;
    if(!lowLevelInitDone){
        tcpipInit();
        wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
        esp_err_t err = esp_wifi_init(&cfg);
        if(err){
            log_e("esp_wifi_init %d", err);
            return false;
        }
        esp_wifi_set_storage(WIFI_STORAGE_FLASH);
        esp_wifi_set_mode(WIFI_MODE_NULL);
        lowLevelInitDone = true;
    }
    return true;
}

static bool wifiLowLevelDeinit(){
    //deinit not working yet!
    //esp_wifi_deinit();
    return true;
}

static bool _esp_wifi_started = false;

static bool espWiFiStart(){
    if(_esp_wifi_started){
        return true;
    }
    if(!wifiLowLevelInit()){
        return false;
    }
    esp_err_t err = esp_wifi_start();
    if (err != ESP_OK) {
        log_e("esp_wifi_start %d", err);
        wifiLowLevelDeinit();
        return false;
    }
    _esp_wifi_started = true;
    return true;
}

static bool espWiFiStop(){
    esp_err_t err;
    if(!_esp_wifi_started){
        return true;
    }
    err = esp_wifi_stop();
    if(err){
        log_e("Could not stop WiFi! %u", err);
        return false;
    }
    _esp_wifi_started = false;
    return wifiLowLevelDeinit();
}

// -----------------------------------------------------------------------------------------------------------------------
// ------------------------------------------------- Generic WiFi function -----------------------------------------------
// -----------------------------------------------------------------------------------------------------------------------

// arduino dont like std::vectors move static here
static std::vector<WiFiEventCbList_t> cbEventList;

bool WiFiGenericClass::_persistent = true;
wifi_mode_t WiFiGenericClass::_forceSleepLastMode = WIFI_MODE_NULL;

WiFiGenericClass::WiFiGenericClass()
{

}

/**
 * set callback function
 * @param cbEvent WiFiEventCb
 * @param event optional filter (WIFI_EVENT_MAX is all events)
 */
void WiFiGenericClass::onEvent(WiFiEventCb cbEvent, system_event_id_t event)
{
    if(!cbEvent) {
        return;
    }
    WiFiEventCbList_t newEventHandler;
    newEventHandler.cb = cbEvent;
    newEventHandler.event = event;
    cbEventList.push_back(newEventHandler);
}

/**
 * removes a callback form event handler
 * @param cbEvent WiFiEventCb
 * @param event optional filter (WIFI_EVENT_MAX is all events)
 */
void WiFiGenericClass::removeEvent(WiFiEventCb cbEvent, system_event_id_t event)
{
    if(!cbEvent) {
        return;
    }

    for(uint32_t i = 0; i < cbEventList.size(); i++) {
        WiFiEventCbList_t entry = cbEventList[i];
        if(entry.cb == cbEvent && entry.event == event) {
            cbEventList.erase(cbEventList.begin() + i);
        }
    }
}

/**
 * callback for WiFi events
 * @param arg
 */
#if ARDUHAL_LOG_LEVEL >= ARDUHAL_LOG_LEVEL_DEBUG
const char * system_event_names[] = { "WIFI_READY", "SCAN_DONE", "STA_START", "STA_STOP", "STA_CONNECTED", "STA_DISCONNECTED", "STA_AUTHMODE_CHANGE", "STA_GOT_IP", "STA_WPS_ER_SUCCESS", "STA_WPS_ER_FAILED", "STA_WPS_ER_TIMEOUT", "STA_WPS_ER_PIN", "AP_START", "AP_STOP", "AP_STACONNECTED", "AP_STADISCONNECTED", "AP_PROBEREQRECVED", "AP_STA_GOT_IP6", "ETH_START", "ETH_STOP", "ETH_CONNECTED", "ETH_DISCONNECTED", "ETH_GOT_IP", "MAX"};
#endif
#if ARDUHAL_LOG_LEVEL >= ARDUHAL_LOG_LEVEL_WARN
const char * system_event_reasons[] = { "UNSPECIFIED", "AUTH_EXPIRE", "AUTH_LEAVE", "ASSOC_EXPIRE", "ASSOC_TOOMANY", "NOT_AUTHED", "NOT_ASSOCED", "ASSOC_LEAVE", "ASSOC_NOT_AUTHED", "DISASSOC_PWRCAP_BAD", "DISASSOC_SUPCHAN_BAD", "IE_INVALID", "MIC_FAILURE", "4WAY_HANDSHAKE_TIMEOUT", "GROUP_KEY_UPDATE_TIMEOUT", "IE_IN_4WAY_DIFFERS", "GROUP_CIPHER_INVALID", "PAIRWISE_CIPHER_INVALID", "AKMP_INVALID", "UNSUPP_RSN_IE_VERSION", "INVALID_RSN_IE_CAP", "802_1X_AUTH_FAILED", "CIPHER_SUITE_REJECTED", "BEACON_TIMEOUT", "NO_AP_FOUND", "AUTH_FAIL", "ASSOC_FAIL", "HANDSHAKE_TIMEOUT" };
#define reason2str(r) ((r>176)?system_event_reasons[r-176]:system_event_reasons[r-1])
#endif
esp_err_t WiFiGenericClass::_eventCallback(void *arg, system_event_t *event)
{
    log_d("Event: %d - %s", event->event_id, system_event_names[event->event_id]);
    if(event->event_id == SYSTEM_EVENT_SCAN_DONE) {
        WiFiScanClass::_scanDone();
    } else if(event->event_id == SYSTEM_EVENT_STA_DISCONNECTED) {
        uint8_t reason = event->event_info.disconnected.reason;
        log_w("Reason: %u - %s", reason, reason2str(reason));
        if(reason == WIFI_REASON_NO_AP_FOUND) {
            WiFiSTAClass::_setStatus(WL_NO_SSID_AVAIL);
        } else if(reason == WIFI_REASON_AUTH_FAIL || reason == WIFI_REASON_ASSOC_FAIL) {
            WiFiSTAClass::_setStatus(WL_CONNECT_FAILED);
        } else if(reason == WIFI_REASON_BEACON_TIMEOUT || reason == WIFI_REASON_HANDSHAKE_TIMEOUT) {
            WiFiSTAClass::_setStatus(WL_CONNECTION_LOST);
        } else if(reason == WIFI_REASON_AUTH_EXPIRE) {
            WiFi.begin();
        } else {
            WiFiSTAClass::_setStatus(WL_DISCONNECTED);
        }
    } else if(event->event_id == SYSTEM_EVENT_STA_START) {
        WiFiSTAClass::_setStatus(WL_DISCONNECTED);
    } else if(event->event_id == SYSTEM_EVENT_STA_STOP) {
        WiFiSTAClass::_setStatus(WL_NO_SHIELD);
    } else if(event->event_id == SYSTEM_EVENT_STA_GOT_IP) {
        WiFiSTAClass::_setStatus(WL_CONNECTED);
    }

    for(uint32_t i = 0; i < cbEventList.size(); i++) {
        WiFiEventCbList_t entry = cbEventList[i];
        if(entry.cb) {
            if(entry.event == (system_event_id_t) event->event_id || entry.event == SYSTEM_EVENT_MAX) {
                entry.cb((system_event_id_t) event->event_id);
            }
        }
    }
    return ESP_OK;
}

/**
 * Return the current channel associated with the network
 * @return channel (1-13)
 */
int32_t WiFiGenericClass::channel(void)
{
    uint8_t primaryChan;
    wifi_second_chan_t secondChan;
    esp_wifi_get_channel(&primaryChan, &secondChan);
    return primaryChan;
}


/**
 * store WiFi config in SDK flash area
 * @param persistent
 */
void WiFiGenericClass::persistent(bool persistent)
{
    _persistent = persistent;
}


/**
 * set new mode
 * @param m WiFiMode_t
 */
bool WiFiGenericClass::mode(wifi_mode_t m)
{
    wifi_mode_t cm = getMode();
    if(cm == WIFI_MODE_MAX){
        return false;
    }
    if(cm == m) {
        return true;
    }
    esp_err_t err;
    err = esp_wifi_set_mode(m);
    if(err){
        log_e("Could not set mode! %u", err);
        return false;
    }
    if(m){
        return espWiFiStart();
    }
    return espWiFiStop();
}

/**
 * get WiFi mode
 * @return WiFiMode
 */
wifi_mode_t WiFiGenericClass::getMode()
{
    if(!wifiLowLevelInit()){
        return WIFI_MODE_MAX;
    }
    uint8_t mode;
    esp_wifi_get_mode((wifi_mode_t*)&mode);
    return (wifi_mode_t)mode;
}

/**
 * control STA mode
 * @param enable bool
 * @return ok
 */
bool WiFiGenericClass::enableSTA(bool enable)
{

    wifi_mode_t currentMode = getMode();
    bool isEnabled = ((currentMode & WIFI_MODE_STA) != 0);

    if(isEnabled != enable) {
        if(enable) {
            return mode((wifi_mode_t)(currentMode | WIFI_MODE_STA));
        } else {
            return mode((wifi_mode_t)(currentMode & (~WIFI_MODE_STA)));
        }
    } else {
        return true;
    }
}

/**
 * control AP mode
 * @param enable bool
 * @return ok
 */
bool WiFiGenericClass::enableAP(bool enable)
{

    wifi_mode_t currentMode = getMode();
    bool isEnabled = ((currentMode & WIFI_MODE_AP) != 0);

    if(isEnabled != enable) {
        if(enable) {
            return mode((wifi_mode_t)(currentMode | WIFI_MODE_AP));
        } else {
            return mode((wifi_mode_t)(currentMode & (~WIFI_MODE_AP)));
        }
    } else {
        return true;
    }
}


// -----------------------------------------------------------------------------------------------------------------------
// ------------------------------------------------ Generic Network function ---------------------------------------------
// -----------------------------------------------------------------------------------------------------------------------

static bool _dns_busy = false;

/**
 * DNS callback
 * @param name
 * @param ipaddr
 * @param callback_arg
 */
static void wifi_dns_found_callback(const char *name, const ip_addr_t *ipaddr, void *callback_arg)
{
    if(ipaddr) {
        (*reinterpret_cast<IPAddress*>(callback_arg)) = ipaddr->u_addr.ip4.addr;
    }
    _dns_busy = false;
}

/**
 * Resolve the given hostname to an IP address.
 * @param aHostname     Name to be resolved
 * @param aResult       IPAddress structure to store the returned IP address
 * @return 1 if aIPAddrString was successfully converted to an IP address,
 *          else error code
 */
int WiFiGenericClass::hostByName(const char* aHostname, IPAddress& aResult)
{
    ip_addr_t addr;
    aResult = static_cast<uint32_t>(0);

    _dns_busy = true;
    err_t err = dns_gethostbyname(aHostname, &addr, &wifi_dns_found_callback, &aResult);
    if(err == ERR_OK && addr.u_addr.ip4.addr) {
        aResult = addr.u_addr.ip4.addr;
        _dns_busy = false;
    } else if(err == ERR_INPROGRESS) {
        while(_dns_busy){
            delay(1);
        }
    } else {
        _dns_busy = false;
        return 0;
    }
    return 1;
}