#include "NetworkConfig.hpp"
#include "Hardware/Eth.hpp"
#include "Wifi.hpp"
#include "knx_facade.h"
#include "esp_log.h"
#include <cstring>

static const char* TAG = "NetworkConfig";

// Parameter offsets within the NW module's parameter block.
// These must match the offsets generated by OpenKNXproducer for the NW module.
// The producer assigns a base offset; these are relative offsets within Network.share.xml.
// After running the producer, update NW_PARAM_BASE to the assigned base offset.

static constexpr uint16_t NW_PARAM_BASE = 0; // Will be set by producer

// Byte 0: Flags
static constexpr uint16_t NW_FLAGS         = NW_PARAM_BASE + 0;
static constexpr uint8_t  NW_LAN_ENABLE_MASK  = 0x80; // Bit 7
static constexpr uint8_t  NW_LAN_STATIC_MASK  = 0x40; // Bit 6
static constexpr uint8_t  NW_WLAN_ENABLE_MASK = 0x20; // Bit 5
static constexpr uint8_t  NW_WLAN_STATIC_MASK = 0x10; // Bit 4

// LAN IP config: bytes 1-16
static constexpr uint16_t NW_LAN_IP       = NW_PARAM_BASE + 1;
static constexpr uint16_t NW_LAN_SUBNET   = NW_PARAM_BASE + 5;
static constexpr uint16_t NW_LAN_GATEWAY  = NW_PARAM_BASE + 9;
static constexpr uint16_t NW_LAN_DNS      = NW_PARAM_BASE + 13;

// WLAN IP config: bytes 17-32
static constexpr uint16_t NW_WLAN_IP      = NW_PARAM_BASE + 17;
static constexpr uint16_t NW_WLAN_SUBNET  = NW_PARAM_BASE + 21;
static constexpr uint16_t NW_WLAN_GATEWAY = NW_PARAM_BASE + 25;
static constexpr uint16_t NW_WLAN_DNS     = NW_PARAM_BASE + 29;

// WLAN credentials: bytes 33-129
static constexpr uint16_t NW_WLAN_WPA     = NW_PARAM_BASE + 33;
static constexpr uint16_t NW_WLAN_SSID    = NW_PARAM_BASE + 34;
static constexpr uint16_t NW_WLAN_PASS    = NW_PARAM_BASE + 66;
static constexpr uint16_t NW_WLAN_SSID_LEN = 32;
static constexpr uint16_t NW_WLAN_PASS_LEN = 64;

extern KnxFacade<Esp32IdfPlatform, Bau07B0> knx;

static void readIpOctets(uint16_t offset, uint8_t out[4]) {
    for (int i = 0; i < 4; i++) {
        out[i] = knx.paramByte(offset + i);
    }
}

static std::string readParamString(uint16_t offset, uint16_t maxLen) {
    char buf[128] = {};
    uint16_t len = (maxLen < sizeof(buf) - 1) ? maxLen : sizeof(buf) - 1;
    for (uint16_t i = 0; i < len; i++) {
        buf[i] = (char)knx.paramByte(offset + i);
        if (buf[i] == '\0') break;
    }
    buf[len] = '\0';
    return std::string(buf);
}

static wifi_auth_mode_t wpaVersionToAuthMode(uint8_t wpaVersion) {
    switch (wpaVersion) {
        case 1:  return WIFI_AUTH_WPA3_PSK;
        case 2:  return WIFI_AUTH_WPA2_WPA3_PSK;
        default: return WIFI_AUTH_WPA2_PSK;
    }
}

void NetworkConfig::applyFromKnx() {
    if (!knx.configured()) {
        ESP_LOGW(TAG, "KNX not configured, using default network settings");
        return;
    }

    uint8_t flags = knx.paramByte(NW_FLAGS);
    bool lanEnabled  = (flags & NW_LAN_ENABLE_MASK) != 0;
    bool lanStatic   = (flags & NW_LAN_STATIC_MASK) != 0;
    bool wlanEnabled = (flags & NW_WLAN_ENABLE_MASK) != 0;
    bool wlanStatic  = (flags & NW_WLAN_STATIC_MASK) != 0;

    ESP_LOGI(TAG, "Network config: LAN=%s(%s) WLAN=%s(%s)",
        lanEnabled ? "on" : "off", lanStatic ? "static" : "dhcp",
        wlanEnabled ? "on" : "off", wlanStatic ? "static" : "dhcp");

    // Apply LAN static IP if configured
    if (lanEnabled && lanStatic) {
        StaticIpConfig cfg = {};
        readIpOctets(NW_LAN_IP, cfg.ip);
        readIpOctets(NW_LAN_SUBNET, cfg.subnet);
        readIpOctets(NW_LAN_GATEWAY, cfg.gateway);
        readIpOctets(NW_LAN_DNS, cfg.dns);

        ESP_LOGI(TAG, "LAN static: %d.%d.%d.%d/%d.%d.%d.%d gw %d.%d.%d.%d dns %d.%d.%d.%d",
            cfg.ip[0], cfg.ip[1], cfg.ip[2], cfg.ip[3],
            cfg.subnet[0], cfg.subnet[1], cfg.subnet[2], cfg.subnet[3],
            cfg.gateway[0], cfg.gateway[1], cfg.gateway[2], cfg.gateway[3],
            cfg.dns[0], cfg.dns[1], cfg.dns[2], cfg.dns[3]);

        Eth::instance().applyStaticIp(cfg);
    }

    // Initialize WLAN if enabled
    if (wlanEnabled) {
        Wifi::instance().init();

        if (wlanStatic) {
            StaticIpConfig cfg = {};
            readIpOctets(NW_WLAN_IP, cfg.ip);
            readIpOctets(NW_WLAN_SUBNET, cfg.subnet);
            readIpOctets(NW_WLAN_GATEWAY, cfg.gateway);
            readIpOctets(NW_WLAN_DNS, cfg.dns);

            ESP_LOGI(TAG, "WLAN static: %d.%d.%d.%d/%d.%d.%d.%d gw %d.%d.%d.%d dns %d.%d.%d.%d",
                cfg.ip[0], cfg.ip[1], cfg.ip[2], cfg.ip[3],
                cfg.subnet[0], cfg.subnet[1], cfg.subnet[2], cfg.subnet[3],
                cfg.gateway[0], cfg.gateway[1], cfg.gateway[2], cfg.gateway[3],
                cfg.dns[0], cfg.dns[1], cfg.dns[2], cfg.dns[3]);

            Wifi::instance().applyStaticIp(cfg);
        }

        // Read WLAN credentials from KNX parameters
        std::string ssid = readParamString(NW_WLAN_SSID, NW_WLAN_SSID_LEN);
        std::string password = readParamString(NW_WLAN_PASS, NW_WLAN_PASS_LEN);
        uint8_t wpaVersion = knx.paramByte(NW_WLAN_WPA);
        wifi_auth_mode_t authMode = wpaVersionToAuthMode(wpaVersion);

        if (!ssid.empty()) {
            ESP_LOGI(TAG, "WLAN connecting to SSID: %s (WPA=%d)", ssid.c_str(), wpaVersion);
            Wifi::instance().connect(ssid.c_str(), password.c_str(), authMode);
        } else {
            ESP_LOGW(TAG, "WLAN enabled but no SSID configured");
        }
    }
}