// DragonX Wallet - ImGui Edition
// Copyright 2024-2026 The Hush Developers
// Released under the GPLv3
//
// provision_state.h - state of the startup "node files" job (App::startStartupFilesProvision): on Windows it
// extracts the bundled Sapling params / asmap / node / miner from the .exe, on Linux/macOS it copies them
// from the executable's directory, and on full-node builds it then verifies the Sapling params. The job runs
// on a worker thread; the UI thread only polls this. No app dependencies, so tests include it directly.
#pragma once

#include <atomic>
#include <chrono>
#include <condition_variable>
#include <cstdint>
#include <mutex>

namespace dragonx {
namespace resources {

enum class ProvisionPhase : int { Idle = 0, Extracting, Copying, Verifying };

// Lock-free progress: written by the worker, read by the UI every frame.
struct ProvisionProgress {
    std::atomic<std::uint64_t> bytesDone{0};
    std::atomic<std::uint64_t> bytesTotal{0};
    std::atomic<int> phase{static_cast<int>(ProvisionPhase::Idle)};
    void setPhase(ProvisionPhase p) { phase.store(static_cast<int>(p), std::memory_order_relaxed); }
    ProvisionPhase getPhase() const { return static_cast<ProvisionPhase>(phase.load(std::memory_order_relaxed)); }
};

// 0..100; 0 while the total is unknown.
inline int provisionPercent(std::uint64_t done, std::uint64_t total)
{
    if (total == 0) return 0;
    if (done >= total) return 100;
    return static_cast<int>((done * 100u) / total);
}

// The chip stays hidden for a short grace period so a job that ends in a few ms never flashes.
inline bool provisionChipVisible(bool running, double elapsedSeconds, double delaySeconds)
{
    return running && elapsedSeconds >= delaySeconds;
}

// What App::startEmbeddedDaemon() does while the job may still be writing the node files: never launch the
// node over half-written files, never block the UI thread (defer + replay), workers simply wait.
enum class DaemonStartGate { Proceed, Defer, Wait };
inline DaemonStartGate daemonStartGate(bool jobRunning, bool onUiThread)
{
    if (!jobRunning) return DaemonStartGate::Proceed;
    return onUiThread ? DaemonStartGate::Defer : DaemonStartGate::Wait;
}

class StartupProvision {
public:
    struct Result {
        bool extractOk = true;   // every needed file written/copied (false: disk full / permissions / AV)
        bool verifyOk  = true;   // Sapling SHA-256 check (full node only)
        bool cancelled = false;  // shutdown stopped it; nothing is wrong
    };
    enum class State : int { Idle, Running, Finished, Reaped };

    ProvisionProgress progress;
    // The Sapling param repair copy (replace the daemon-dir params from the bundle, ~51.5 MB) ran this session:
    // set by the job and by App::startEmbeddedDaemon(), so a still-failing verify never repeats it on every
    // connect retry (the UI thread).
    std::atomic<bool> paramRepairTried{false};

    void begin() {
        std::lock_guard<std::mutex> lk(m_);
        state_ = State::Running;
        startedAt_ = std::chrono::steady_clock::now();
    }
    // Nothing needed doing (the steady-state launch): no thread was started.
    void markNothingToDo() { std::lock_guard<std::mutex> lk(m_); state_ = State::Reaped; }
    void finish(const Result& r) {
        { std::lock_guard<std::mutex> lk(m_); result_ = r; state_ = State::Finished; }
        cv_.notify_all();
    }
    bool isRunning() const { std::lock_guard<std::mutex> lk(m_); return state_ == State::Running; }
    // Non-reaping peek: the job has ended and shutdown cancelled it (synchronized with finish() through m_).
    bool endedCancelled() const {
        std::lock_guard<std::mutex> lk(m_);
        return state_ != State::Running && result_.cancelled;
    }
    // App::hasPendingBackgroundResults(): finished and not yet reaped (the reap needs one update() tick).
    // NOT while Running: nothing is reapable then, and the chip already requests progress frames when visible.
    bool hasCompletion() const { std::lock_guard<std::mutex> lk(m_); return state_ == State::Finished; }
    // UI thread: true exactly once, after the job finished.
    bool takeCompletion(Result* out) {
        std::lock_guard<std::mutex> lk(m_);
        if (state_ != State::Finished) return false;
        if (out) *out = result_;
        state_ = State::Reaped;
        return true;
    }
    // Worker threads: true when the job is no longer running.
    bool waitUntilDone(int timeoutMs) {
        std::unique_lock<std::mutex> lk(m_);
        cv_.wait_for(lk, std::chrono::milliseconds(timeoutMs), [&] { return state_ != State::Running; });
        return state_ != State::Running;
    }
    double elapsedSeconds() const {
        std::lock_guard<std::mutex> lk(m_);
        if (state_ != State::Running) return 0.0;
        return std::chrono::duration<double>(std::chrono::steady_clock::now() - startedAt_).count();
    }

private:
    mutable std::mutex m_;
    std::condition_variable cv_;
    State state_ = State::Idle;
    Result result_;
    std::chrono::steady_clock::time_point startedAt_{};
};

} // namespace resources
} // namespace dragonx