#pragma once
#include "led_transport.h"
#include <winsock2.h>      // SOCKET, sockaddr_in — MUST precede any windows.h
#include <ws2tcpip.h>      // inet_pton, inet_ntop
#include <atomic>
#include <cstdint>
#include <string>

// ----------------------------------------------------------------------------
// WLED DDP-over-UDP transport (TRNS-02). Implements ILedTransport.
//
// Reference: 15-RESEARCH.md §Pattern 1 (class shape) + §Pattern 2 (DDP encoder)
//            + §Pattern 3 (one-shot HTTP probe). File layout per D-16.
//
// Lifecycle:
//   Open(ipv4String):
//     1. Validate ipv4String via inet_pton(AF_INET) — D-05 / T-15-01.
//        Hostnames, paths, garbage all rejected.
//     2. ProbeJsonInfo() — raw-socket HTTP/1.0 GET /json/info to ipv4:80,
//        parse "count":N — D-07/D-08. Bounded ~500 ms.
//     3. PostJsonState() — best-effort POST {"seg":[...col[[0,0,0]]]} to
//        /json/state — Pitfall 9 (segment-baseline override).
//     4. socket(AF_INET, SOCK_DGRAM, 0); cache sockaddr_in for ipv4:4048
//        — D-06 (DDP port hard-coded, not configurable).
//   Close():
//     closesocket(); m_bOpen.store(false); idempotent.
//   SendRgbFrame:
//     10-byte DDP header + numLeds*3 RGB bytes; one sendto; double-send
//     with 20 ms gap (Pitfall 8 — first-frame quirk parity with USB);
//     on failure -> Close() + return false.
//   SendBrightness/SendPower:
//     Raw-socket HTTP POST /json/state with {"bri":N} / {"on":bool}.
//
// IMPORTANT: WSAStartup / WSACleanup are NOT owned by this class. They are
// owned by DeviceProvider::Init / Cleanup as a single driver-level pair
// (15-RESEARCH.md §Code Examples §3). This class assumes Winsock is already
// initialized when Open() is called.
//
// Threat-model notes (15-02 PLAN <threat_model>):
//   T-15-01: inet_pton strict IPv4 validation.
//   T-15-03: bounded HTTP request/response buffers (snprintf with sizeof()).
//   T-15-06: NEVER log the raw /json/info body — only the parsed count.
// ----------------------------------------------------------------------------
class WledDdpTransport : public ILedTransport {
public:
    WledDdpTransport();
    ~WledDdpTransport() override;

    WledDdpTransport(const WledDdpTransport&) = delete;
    WledDdpTransport& operator=(const WledDdpTransport&) = delete;

    // portName must be a valid IPv4 dotted quad (e.g. "192.168.1.42"). D-05.
    // Returns true if probe succeeded AND UDP socket was bound for host:4048.
    bool Open(const std::string& portName) override;
    void Close() override;
    bool IsOpen() const override;

    bool SendRgbFrame(const uint8_t* rgb, int numLeds) override;
    bool SendBrightness(uint8_t value) override;
    bool SendPower(bool on) override;

    unsigned long LastErrorCode() const override;

    // Diagnostic: WLED-reported LED count from /json/info (0 if not yet probed).
    // Plan 15-03 reads this to log a WARN if mismatch with kBackglowMaxLeds (D-08).
    int ReportedLedCount() const;

private:
    SOCKET                          m_sock;             // INVALID_SOCKET when closed
    sockaddr_in                     m_dest;             // host:4048 cached after Open
    std::atomic<bool>               m_bOpen;
    std::atomic<unsigned long>      m_lastError;        // last WSAGetLastError() or 0
    int                             m_reportedLedCount; // from /json/info; 0 until first Open
    uint8_t                         m_seq;              // DDP sequence 1..15, wraps; reset in Open
};