//
// Created by jedi on 25.06.21.
//

#include "wifi.h"
#include "log.h"

#include <cstdlib>
#include <cstring>
#include <FreeRTOS.h>
#include <task.h>
#include <sockets.h>

extern "C" {
#include <sysparam.h>
#include <lwipopts.h>
#include <espressif/user_interface.h>
}

#include <espressif/esp_wifi.h>
#include <espressif/esp_sta.h>
#include <espressif/esp_softap.h>
#include <dhcpserver.h>

const char *wificfg_default_ssid = "fiatlux_%02X%02X%02X";
const char *wificfg_default_password = "fiatlux02";
const char *wificfg_default_hostname = "fiatlux-%02x%02x%02x";

char *wifi_sta_ssid = nullptr;
char *wifi_sta_password = nullptr;
char *wifi_ap_ssid = nullptr;
char *wifi_ap_password = nullptr;

SemaphoreHandle_t wifi_available_semaphore = nullptr;
SemaphoreHandle_t wifi_alive = nullptr;

[[noreturn]] static void dns_task(void *pvParameters) {
    char *wifi_ap_ip_addr = nullptr;
    sysparam_get_string("wifi_ap_ip_addr", &wifi_ap_ip_addr);
    if(!wifi_ap_ip_addr) {
        syslog("dns: no ip address\n");
        vTaskDelete(nullptr);
    }
    ip4_addr_t server_addr;
    server_addr.addr = ipaddr_addr(wifi_ap_ip_addr);

#if LWIP_IPV6
    int fd = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
    sockaddr_in6 serv_addr;
    memset(&serv_addr, '0', sizeof(serv_addr));
    serv_addr.sin6_family = AF_INET6;
    serv_addr.sin6_port = htons(53);
    serv_addr.sin6_flowinfo = 0;
    serv_addr.sin6_addr = in6addr_any;
    serv_addr.sin6_scope_id = IP6_NO_ZONE;
#else
    int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
    sockaddr_in serv_addr;
    memset(&serv_addr, '0', sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(53);
#endif
    bind(fd, (sockaddr *) &serv_addr, sizeof(serv_addr));

    const ifreq ifreq0 = {"en0"};
    const ifreq ifreq1 = {"en1"};
    setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE,
               sdk_wifi_get_opmode() == STATIONAP_MODE ? &ifreq1 : &ifreq0,
               sizeof(ifreq0));

    for (;;) {
        uint8_t buffer[96];
        sockaddr_storage src_addr;
        socklen_t src_addr_len = sizeof(src_addr);
        ssize_t count = recvfrom(fd, buffer, sizeof(buffer), 0, (sockaddr *) &src_addr, &src_addr_len);

        /* Drop messages that are too large to send a response in the buffer */
        if(count > 0 && count + 16 <= (ssize_t) sizeof(buffer)) {
            size_t qname_len = strlen((const char *) (buffer + 12)) + 1;
            uint32_t reply_len = 2 + 10 + qname_len + 16 + 4;

            uint8_t *head = buffer + 2;
            *head++ = 0x80; // Flags
            *head++ = 0x00;
            *head++ = 0x00; // Q count
            *head++ = 0x01;
            *head++ = 0x00; // A count
            *head++ = 0x01;
            *head++ = 0x00; // Auth count
            *head++ = 0x00;
            *head++ = 0x00; // Add count
            *head++ = 0x00;
            head += qname_len;
            *head++ = 0x00; // Q type
            *head++ = 0x01;
            *head++ = 0x00; // Q class
            *head++ = 0x01;
            *head++ = 0xC0; // LBL offs
            *head++ = 0x0C;
            *head++ = 0x00; // Type
            *head++ = 0x01;
            *head++ = 0x00; // Class
            *head++ = 0x01;
            *head++ = 0x00; // TTL
            *head++ = 0x00;
            *head++ = 0x00;
            *head++ = 0x78;
            *head++ = 0x00; // RD len
            *head++ = 0x04;
            *head++ = ip4_addr1(&server_addr);
            *head++ = ip4_addr2(&server_addr);
            *head++ = ip4_addr3(&server_addr);
            *head++ = ip4_addr4(&server_addr);

            sendto(fd, buffer, reply_len, 0, (sockaddr *) &src_addr, src_addr_len);
        }
    }
}

extern "C" void wifi_task(void *pvParameters) {
    (void) pvParameters;
    /* Default a hostname. */
    char *hostname = nullptr;
    sysparam_get_string("hostname", &hostname);
    if(!hostname && wificfg_default_hostname) {
        uint8_t macaddr[6];
        char name[32];
        sdk_wifi_get_macaddr(1, macaddr);
        snprintf(name, sizeof(name), wificfg_default_hostname, macaddr[3],
                 macaddr[4], macaddr[5]);
        sysparam_set_string("hostname", name);
    }
    if(hostname) {
        free(hostname);
    }

    sysparam_get_string("wifi_ap_ssid", &wifi_ap_ssid);
    sysparam_get_string("wifi_ap_password", &wifi_ap_password);
    sysparam_get_string("wifi_sta_ssid", &wifi_sta_ssid);
    sysparam_get_string("wifi_sta_password", &wifi_sta_password);

    int8_t wifi_sta_enable = 1;
    int8_t wifi_ap_enable = 1;
    sysparam_get_int8("wifi_sta_enable", &wifi_sta_enable);
    sysparam_get_int8("wifi_ap_enable", &wifi_ap_enable);
    wifi_ap_enable = 0;

    int8_t wifi_sta_disabled_restarts = 0;
    sysparam_get_int8("wifi_sta_disabled_restarts", &wifi_sta_disabled_restarts);
    if(wifi_sta_disabled_restarts > 0) {
        wifi_sta_enable = 0;
        wifi_sta_disabled_restarts--;
        sysparam_set_int8("wifi_sta_disabled_restarts", wifi_sta_disabled_restarts);
    }

    int8_t wifi_ap_disabled_restarts = 0;
    sysparam_get_int8("wifi_ap_disabled_restarts", &wifi_ap_disabled_restarts);
    if(wifi_ap_disabled_restarts > 0) {
        wifi_ap_enable = 0;
        wifi_ap_disabled_restarts--;
        sysparam_set_int8("wifi_ap_disabled_restarts", wifi_ap_disabled_restarts);
    }

    /* Validate the configuration. */

    if(wifi_sta_enable && (!wifi_sta_ssid || !wifi_sta_password ||
                           strlen(wifi_sta_ssid) < 1 ||
                           strlen(wifi_sta_ssid) > 32 ||
                           !wifi_sta_password ||
                           strlen(wifi_sta_password) < 8 ||
                           strlen(wifi_sta_password) >= 64)) {
        wifi_sta_enable = 0;
    }

    if(!wifi_sta_enable)
        wifi_ap_enable = 1;

    if(wifi_ap_enable) {
        /* Default AP ssid and password. */
        if(!wifi_ap_ssid && wificfg_default_ssid) {
            uint8_t macaddr[6];
            char ssid[32];
            sdk_wifi_get_macaddr(1, macaddr);
            snprintf(ssid, sizeof(ssid), wificfg_default_ssid, macaddr[3],
                     macaddr[4], macaddr[5]);
            sysparam_set_string("wifi_ap_ssid", ssid);
            sysparam_get_string("wifi_ap_ssid", &wifi_ap_ssid);

            if(!wifi_ap_password && wificfg_default_password) {
                sysparam_set_string("wifi_ap_password", wificfg_default_password);
                sysparam_get_string("wifi_ap_password", &wifi_ap_password);
            }
        }
        printf("ssid: %s\n", wifi_ap_ssid);

        /* If the ssid and password are not valid then disable the AP interface. */
        if(!wifi_ap_ssid || strlen(wifi_ap_ssid) < 1 || strlen(wifi_ap_ssid) >= 32 ||
           !wifi_ap_password || strlen(wifi_ap_password) < 8 || strlen(wifi_ap_password) >= 64) {
            syslog("len err\n");
            wifi_ap_enable = 0;
        }
    }

    int8_t wifi_mode = NULL_MODE;
    if(wifi_sta_enable && wifi_ap_enable)
        wifi_mode = STATIONAP_MODE;
    else if(wifi_sta_enable)
        wifi_mode = STATION_MODE;
    else if(wifi_ap_enable)
        wifi_mode = SOFTAP_MODE;
    sdk_wifi_set_opmode(wifi_mode);

    if(wifi_sta_enable) {
        printf("try STA Mode: %s %s\n", wifi_sta_ssid, wifi_sta_password);
        sdk_station_config config{};
        strcpy((char *) config.ssid, wifi_sta_ssid);
        strcpy((char *) config.password, wifi_sta_password);
        config.bssid_set = 0;

        int8_t wifi_sta_dhcp = 1;
        sysparam_get_int8("wifi_sta_dhcp", &wifi_sta_dhcp);

        if(!wifi_sta_dhcp) {
            char *wifi_sta_ip_addr = nullptr;
            char *wifi_sta_netmask = nullptr;
            char *wifi_sta_gateway = nullptr;
            sysparam_get_string("wifi_sta_ip_addr", &wifi_sta_ip_addr);
            sysparam_get_string("wifi_sta_netmask", &wifi_sta_netmask);
            sysparam_get_string("wifi_sta_gateway", &wifi_sta_gateway);

            if(wifi_sta_ip_addr && strlen(wifi_sta_ip_addr) > 4 &&
               wifi_sta_netmask && strlen(wifi_sta_netmask) > 4 &&
               wifi_sta_gateway && strlen(wifi_sta_gateway) > 4) {
                sdk_wifi_station_dhcpc_stop();
                ip_info info{};
                memset(&info, 0x0, sizeof(info));
                info.ip.addr = ipaddr_addr(wifi_sta_ip_addr);
                info.netmask.addr = ipaddr_addr(wifi_sta_netmask);
                info.gw.addr = ipaddr_addr(wifi_sta_gateway);
                sdk_wifi_set_ip_info(STATION_IF, &info);
            }
            if(wifi_sta_ip_addr) free(wifi_sta_ip_addr);
            if(wifi_sta_netmask) free(wifi_sta_netmask);
            if(wifi_sta_gateway) free(wifi_sta_gateway);
        }

        sdk_wifi_station_set_config(&config);
    }

    if(wifi_ap_enable) {
        printf("try AP Mode: %s %s\n", wifi_ap_ssid, wifi_ap_password);
/* Read and validate paramenters. */
        int8_t wifi_ap_ssid_hidden = 0;
        sysparam_get_int8("wifi_ap_ssid_hidden", &wifi_ap_ssid_hidden);
        if(wifi_ap_ssid_hidden < 0 || wifi_ap_ssid_hidden > 1) {
            wifi_ap_ssid_hidden = 1;
        }

        int8_t wifi_ap_channel = 6;
        sysparam_get_int8("wifi_ap_channel", &wifi_ap_channel);

        if(wifi_ap_channel < 1 || wifi_ap_channel > 14) {
            wifi_ap_channel = 6;
        }

        int8_t wifi_ap_authmode = AUTH_WPA_WPA2_PSK;
        sysparam_get_int8("wifi_ap_authmode", &wifi_ap_authmode);
        if(wifi_ap_authmode != AUTH_OPEN && wifi_ap_authmode != AUTH_WPA_PSK &&
           wifi_ap_authmode != AUTH_WPA2_PSK && wifi_ap_authmode != AUTH_WPA_WPA2_PSK) {
            wifi_ap_authmode = AUTH_WPA_WPA2_PSK;
        }

        int8_t wifi_ap_max_conn = 3;
        sysparam_get_int8("wifi_ap_max_conn", &wifi_ap_max_conn);
        if(wifi_ap_max_conn < 1 || wifi_ap_max_conn > 8) {
            wifi_ap_max_conn = 3;
        }

        int32_t wifi_ap_beacon_interval = 100;
        sysparam_get_int32("wifi_ap_beacon_interval", &wifi_ap_beacon_interval);
        if(wifi_ap_beacon_interval < 0 || wifi_ap_beacon_interval > 1000) {
            wifi_ap_beacon_interval = 100;
        }

        /* Default AP IP address and netmask. */
        char *wifi_ap_ip_addr = nullptr;
        sysparam_get_string("wifi_ap_ip_addr", &wifi_ap_ip_addr);
        if(!wifi_ap_ip_addr) {
            sysparam_set_string("wifi_ap_ip_addr", "172.16.0.1");
            sysparam_get_string("wifi_ap_ip_addr", &wifi_ap_ip_addr);
        }
        char *wifi_ap_netmask = nullptr;
        sysparam_get_string("wifi_ap_netmask", &wifi_ap_netmask);
        if(!wifi_ap_netmask) {
            sysparam_set_string("wifi_ap_netmask", "255.255.0.0");
            sysparam_get_string("wifi_ap_netmask", &wifi_ap_netmask);
        }

        if(strlen(wifi_ap_ip_addr) >= 7 && strlen(wifi_ap_netmask) >= 7) {
            ip_info ap_ip{};
            ap_ip.ip.addr = ipaddr_addr(wifi_ap_ip_addr);
            ap_ip.netmask.addr = ipaddr_addr(wifi_ap_netmask);
            IP4_ADDR(&ap_ip.gw, 0, 0, 0, 0);
            sdk_wifi_set_ip_info(1, &ap_ip);

            sdk_softap_config ap_config{};
            strcpy((char *) ap_config.ssid, wifi_ap_ssid);
            ap_config.ssid_len = strlen(wifi_ap_ssid);
            strcpy((char *) ap_config.password, wifi_ap_password);
            ap_config.channel = static_cast<uint8_t>(wifi_ap_channel);
            ap_config.authmode = static_cast<AUTH_MODE>(wifi_ap_authmode);
            ap_config.ssid_hidden = static_cast<uint8_t>(wifi_ap_ssid_hidden);
            ap_config.max_connection = static_cast<uint8_t>(wifi_ap_max_conn);
            ap_config.beacon_interval = static_cast<uint16_t>(wifi_ap_beacon_interval);

            sdk_wifi_softap_set_config(&ap_config);

            int8_t wifi_ap_dhcp_leases = 4;
            sysparam_get_int8("wifi_ap_dhcp_leases", &wifi_ap_dhcp_leases);

            if(wifi_ap_dhcp_leases) {
                ip4_addr_t first_client_ip;
                first_client_ip.addr = ap_ip.ip.addr + htonl(1);

                int8_t wifi_ap_dns = 1;
                sysparam_get_int8("wifi_ap_dns", &wifi_ap_dns);
                if(wifi_ap_dns < 0 || wifi_ap_dns > 1)
                    wifi_ap_dns = 1;

                dhcpserver_start(&first_client_ip, wifi_ap_dhcp_leases);
                dhcpserver_set_router(&ap_ip.ip);
                if(wifi_ap_dns) {
                    dhcpserver_set_dns(&ap_ip.ip);
                    xTaskCreate(dns_task, "dns_task", 384, nullptr, 2, nullptr);
                }
            }
        }

        free(wifi_ap_ip_addr);
        free(wifi_ap_netmask);
    }

    if(wifi_sta_ssid) free(wifi_sta_ssid);
    if(wifi_sta_password) free(wifi_sta_password);
    if(wifi_ap_ssid) free(wifi_ap_ssid);
    if(wifi_ap_password) free(wifi_ap_password);

    xSemaphoreGive(wifi_available_semaphore);

    //monitor loop connection here
    uint8_t status = 0;
    uint8_t retries = 30;

    if(wifi_sta_enable) {
        while (1) {

            retries = 30;
            while ((status != STATION_GOT_IP) && (retries)) {
                status = sdk_wifi_station_get_connect_status();
                printf("%s: status = %d [%d retries left]\n\r", __func__, status, retries);
                if(status == STATION_WRONG_PASSWORD) {
                    printf("WiFi: wrong password\n\r");
                    break;
                } else if(status == STATION_NO_AP_FOUND) {
                    printf("WiFi: AP not found\n\r");
                    break;
                } else if(status == STATION_CONNECT_FAIL) {
                    printf("WiFi: connection failed\r\n");
                    break;
                }
                vTaskDelay(1000 / portTICK_PERIOD_MS);
                --retries;
            }
            if(status == STATION_GOT_IP) {
                printf("WiFi: Connected\n\r");
                xSemaphoreGive(wifi_alive);
                taskYIELD();
            }

            while ((status = sdk_wifi_station_get_connect_status()) == STATION_GOT_IP) {
                xSemaphoreGive(wifi_alive);
                taskYIELD();
            }
            printf("WiFi: disconnected\n\r");
            sdk_wifi_station_disconnect();
            vTaskDelay(10000 / portTICK_PERIOD_MS);
        }
    } else {
        while(1) {
            vTaskDelay(10000 / portTICK_PERIOD_MS);
        }
    }
}