// Copyright (c) 2010 Satoshi Nakamoto
// Copyright (c) 2012-2020 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef BITCOIN_UI_INTERFACE_H
#define BITCOIN_UI_INTERFACE_H

#include <functional>
#include <memory>
#include <string>

class CBlockIndex;
enum class SynchronizationState;
struct bilingual_str;

namespace boost {
namespace signals2 {
class connection;
}
} // namespace boost

/** General change type (added, updated, removed). */
enum ChangeType
{
    CT_NEW,
    CT_UPDATED,
    CT_DELETED
};

/** Signals for UI communication. */
class CClientUIInterface
{
public:
    /** Flags for CClientUIInterface::ThreadSafeMessageBox */
    enum MessageBoxFlags
    {
        ICON_INFORMATION    = 0,
        ICON_WARNING        = (1U << 0),
        ICON_ERROR          = (1U << 1),
        /**
         * Mask of all available icons in CClientUIInterface::MessageBoxFlags
         * This needs to be updated, when icons are changed there!
         */
        ICON_MASK = (ICON_INFORMATION | ICON_WARNING | ICON_ERROR),

        /** These values are taken from qmessagebox.h "enum StandardButton" to be directly usable */
        BTN_OK      = 0x00000400U, // QMessageBox::Ok
        BTN_YES     = 0x00004000U, // QMessageBox::Yes
        BTN_NO      = 0x00010000U, // QMessageBox::No
        BTN_ABORT   = 0x00040000U, // QMessageBox::Abort
        BTN_RETRY   = 0x00080000U, // QMessageBox::Retry
        BTN_IGNORE  = 0x00100000U, // QMessageBox::Ignore
        BTN_CLOSE   = 0x00200000U, // QMessageBox::Close
        BTN_CANCEL  = 0x00400000U, // QMessageBox::Cancel
        BTN_DISCARD = 0x00800000U, // QMessageBox::Discard
        BTN_HELP    = 0x01000000U, // QMessageBox::Help
        BTN_APPLY   = 0x02000000U, // QMessageBox::Apply
        BTN_RESET   = 0x04000000U, // QMessageBox::Reset
        /**
         * Mask of all available buttons in CClientUIInterface::MessageBoxFlags
         * This needs to be updated, when buttons are changed there!
         */
        BTN_MASK = (BTN_OK | BTN_YES | BTN_NO | BTN_ABORT | BTN_RETRY | BTN_IGNORE |
                    BTN_CLOSE | BTN_CANCEL | BTN_DISCARD | BTN_HELP | BTN_APPLY | BTN_RESET),

        /** Force blocking, modal message box dialog (not just OS notification) */
        MODAL               = 0x10000000U,

        /** Do not print contents of message to debug log */
        SECURE              = 0x40000000U,

        /** Predefined combinations for certain default usage cases */
        MSG_INFORMATION = ICON_INFORMATION,
        MSG_WARNING = (ICON_WARNING | BTN_OK | MODAL),
        MSG_ERROR = (ICON_ERROR | BTN_OK | MODAL)
    };

#define ADD_SIGNALS_DECL_WRAPPER(signal_name, rtype, ...)                                  \
    rtype signal_name(__VA_ARGS__);                                                        \
    using signal_name##Sig = rtype(__VA_ARGS__);                                           \
    boost::signals2::connection signal_name##_connect(std::function<signal_name##Sig> fn);

    /** Show message box. */
    ADD_SIGNALS_DECL_WRAPPER(ThreadSafeMessageBox, bool, const bilingual_str& message, const std::string& caption, unsigned int style);

    /** If possible, ask the user a question. If not, falls back to ThreadSafeMessageBox(noninteractive_message, caption, style) and returns false. */
    ADD_SIGNALS_DECL_WRAPPER(ThreadSafeQuestion, bool, const bilingual_str& message, const std::string& noninteractive_message, const std::string& caption, unsigned int style);

    /** Progress message during initialization. */
    ADD_SIGNALS_DECL_WRAPPER(InitMessage, void, const std::string& message);

    /** Number of network connections changed. */
    ADD_SIGNALS_DECL_WRAPPER(NotifyNumConnectionsChanged, void, int newNumConnections);

    /** Network activity state changed. */
    ADD_SIGNALS_DECL_WRAPPER(NotifyNetworkActiveChanged, void, bool networkActive);

    /**
     * Status bar alerts changed.
     */
    ADD_SIGNALS_DECL_WRAPPER(NotifyAlertChanged, void, );

    /**
     * Show progress e.g. for verifychain.
     * resume_possible indicates shutting down now will result in the current progress action resuming upon restart.
     */
    ADD_SIGNALS_DECL_WRAPPER(ShowProgress, void, const std::string& title, int nProgress, bool resume_possible);

    /** New block has been accepted */
    ADD_SIGNALS_DECL_WRAPPER(NotifyBlockTip, void, SynchronizationState, const CBlockIndex*);

    /** Best header has changed */
    ADD_SIGNALS_DECL_WRAPPER(NotifyHeaderTip, void, SynchronizationState, const CBlockIndex*);

    /** Banlist did change. */
    ADD_SIGNALS_DECL_WRAPPER(BannedListChanged, void, void);
};

/** Show warning message **/
void InitWarning(const bilingual_str& str);

/** Show error message **/
bool InitError(const bilingual_str& str);
constexpr auto AbortError = InitError;

extern CClientUIInterface uiInterface;

#endif // BITCOIN_UI_INTERFACE_H
