// DragonX Wallet - ImGui Edition
// Copyright 2024-2026 The Hush Developers
// Released under the GPLv3
//
// LiteServerProbe — background latency/IP probe for lite (lightwalletd) servers.
//
// The lite backend only exposes a yes/no checkServerOnline, so the Network tab measures latency
// itself: for each server URL, a libcurl CONNECT_ONLY request does the TCP+TLS handshake (which
// works for gRPC/HTTP-2 lightwalletd endpoints without needing an HTTP response) and records the
// handshake time as latency plus the resolved IP. Runs on a background thread; results are read
// thread-safely from the UI thread and re-run on demand (Refresh).

#pragma once

#include <atomic>
#include <map>
#include <mutex>
#include <string>
#include <thread>
#include <vector>

namespace dragonx {
namespace util {

struct LiteServerProbeResult {
    bool probed = false;     // a probe has completed for this URL
    bool online = false;     // the TCP+TLS handshake succeeded
    int  latencyMs = 0;      // handshake latency (ms); valid when online
    std::string ip;          // resolved primary IP (CURLINFO_PRIMARY_IP)
};

// Pure helper: the host[:port] authority of a URL (scheme + path stripped), for display.
// "https://lite.dragonx.is:443/x" -> "lite.dragonx.is:443"; "" on a malformed input.
std::string liteServerHost(const std::string& url);

class LiteServerProbe {
public:
    LiteServerProbe() = default;
    ~LiteServerProbe();
    LiteServerProbe(const LiteServerProbe&) = delete;
    LiteServerProbe& operator=(const LiteServerProbe&) = delete;

    // Probe each URL on a background thread (replacing any in-flight probe). Results stream in as
    // each server completes; poll results() each frame.
    void start(std::vector<std::string> urls);

    // Snapshot of results so far, keyed by URL.
    std::map<std::string, LiteServerProbeResult> results() const;

    bool busy() const { return busy_.load(); }

private:
    void run(std::vector<std::string> urls);

    mutable std::mutex mutex_;
    std::map<std::string, LiteServerProbeResult> results_;
    std::atomic<bool> busy_{false};
    std::atomic<bool> cancel_{false};
    std::thread worker_;
};

} // namespace util
} // namespace dragonx