#pragma once

#include "data/LedgerCacheInterface.hpp"
#include "util/config/ConfigDefinition.hpp"

#include <concepts>
#include <functional>
#include <optional>
#include <string>
#include <thread>

namespace data {

/**
 * @brief A concept for a class that can save ledger cache asynchronously.
 *
 * This concept defines the interface requirements for any type that manages
 * asynchronous saving of ledger cache to persistent storage.
 */
template <typename T>
concept SomeLedgerCacheSaver = requires(T a) {
    { a.save() } -> std::same_as<void>;
    { a.waitToFinish() } -> std::same_as<void>;
};

/**
 * @brief Manages asynchronous saving of ledger cache to a file.
 *
 * This class provides functionality to save the ledger cache to a file in a separate thread,
 * allowing the main application to continue without blocking. The file path is configured
 * through the application's configuration system.
 */
class LedgerCacheSaver {
    std::optional<std::string> cacheFilePath_;
    std::reference_wrapper<LedgerCacheInterface const> cache_;
    std::optional<std::thread> savingThread_;
    bool isAsync_;

public:
    /**
     * @brief Constructs a LedgerCacheSaver instance.
     *
     * @param config The configuration object containing the cache file path setting
     * @param cache Reference to the ledger cache interface to be saved
     */
    LedgerCacheSaver(
        util::config::ClioConfigDefinition const& config,
        LedgerCacheInterface const& cache
    );

    /**
     * @brief Destructor that ensures the saving thread is properly joined.
     *
     * Waits for any ongoing save operation to complete before destruction.
     */
    ~LedgerCacheSaver();

    /**
     * @brief Initiates an asynchronous save operation of the ledger cache.
     *
     * Spawns a new thread that saves the ledger cache to the configured file path.
     * If no file path is configured, the operation is skipped. Logs the progress
     * and result of the save operation.
     */
    void
    save();

    /**
     * @brief Waits for the saving thread to complete.
     *
     * Blocks until the saving operation finishes if a thread is currently active.
     * Safe to call multiple times or when no save operation is in progress.
     */
    void
    waitToFinish();
};

}  // namespace data