/*
 * Copyright (C) 2008-2017 TrinityCore <http://www.trinitycore.org/>
 * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the
 * Free Software Foundation; either version 2 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef TRINITYCORE_CHAT_H
#define TRINITYCORE_CHAT_H

#include "SharedDefines.h"
#include "StringFormat.h"
#include "WorldSession.h"
#include "RBAC.h"
#include "Packets/ChatPackets.h"

#include <vector>

class ChatHandler;
class Creature;
class Group;
class Player;
class Unit;
class WorldSession;
class WorldObject;

struct GameTele;

class TC_GAME_API ChatCommand
{
    typedef bool(*pHandler)(ChatHandler*, char const*);

    public:
        ChatCommand(char const* name, uint32 permission, bool allowConsole, pHandler handler, std::string help, std::vector<ChatCommand> childCommands = std::vector<ChatCommand>())
            : Name(ASSERT_NOTNULL(name)), Permission(permission), AllowConsole(allowConsole), Handler(handler), Help(std::move(help)), ChildCommands(std::move(childCommands)) { }

        char const* Name;
        uint32 Permission;                   // function pointer required correct align (use uint32)
        bool AllowConsole;
        pHandler Handler;
        std::string Help;
        std::vector<ChatCommand> ChildCommands;
};

class TC_GAME_API ChatHandler
{
    public:
        WorldSession* GetSession() { return m_session; }
        explicit ChatHandler(WorldSession* session) : m_session(session), sentErrorMessage(false) { }
        virtual ~ChatHandler() { }

        static char* LineFromMessage(char*& pos) { char* start = strtok(pos, "\n"); pos = nullptr; return start; }

        // function with different implementation for chat/console
        virtual char const* GetTrinityString(uint32 entry) const;
        virtual void SendSysMessage(char const* str, bool escapeCharacters = false);

        void SendSysMessage(uint32 entry);

        template<typename... Args>
        void PSendSysMessage(const char* fmt, Args&&... args)
        {
            SendSysMessage(Trinity::StringFormat(fmt, std::forward<Args>(args)...).c_str());
        }

        template<typename... Args>
        void PSendSysMessage(uint32 entry, Args&&... args)
        {
            SendSysMessage(PGetParseString(entry, std::forward<Args>(args)...).c_str());
        }

        template<typename... Args>
        std::string PGetParseString(uint32 entry, Args&&... args) const
        {
            return Trinity::StringFormat(GetTrinityString(entry), std::forward<Args>(args)...);
        }

        bool ParseCommands(const char* text);

        static std::vector<ChatCommand> const& getCommandTable();
        static void invalidateCommandTable();

        bool isValidChatMessage(const char* msg);
        void SendGlobalSysMessage(const char *str);

        bool hasStringAbbr(const char* name, const char* part);

        // function with different implementation for chat/console
        virtual bool isAvailable(ChatCommand const& cmd) const;
        virtual bool HasPermission(uint32 permission) const { return m_session->HasPermission(permission); }
        virtual std::string GetNameLink() const { return GetNameLink(m_session->GetPlayer()); }
        virtual bool needReportToTarget(Player* chr) const;
        virtual LocaleConstant GetSessionDbcLocale() const;
        virtual int GetSessionDbLocaleIndex() const;

        bool HasLowerSecurity(Player* target, ObjectGuid guid, bool strong = false);
        bool HasLowerSecurityAccount(WorldSession* target, uint32 account, bool strong = false);

        void SendGlobalGMSysMessage(const char *str);
        Player*   getSelectedPlayer();
        Creature* getSelectedCreature();
        Unit*     getSelectedUnit();
        WorldObject* getSelectedObject();
        // Returns either the selected player or self if there is no selected player
        Player*   getSelectedPlayerOrSelf();

        char*     extractKeyFromLink(char* text, char const* linkType, char** something1 = nullptr);
        char*     extractKeyFromLink(char* text, char const* const* linkTypes, int* found_idx, char** something1 = nullptr);

        // if args have single value then it return in arg2 and arg1 == nullptr
        void      extractOptFirstArg(char* args, char** arg1, char** arg2);
        char*     extractQuotedArg(char* args);

        uint32    extractSpellIdFromLink(char* text);
        ObjectGuid extractGuidFromLink(char* text);
        GameTele const* extractGameTeleFromLink(char* text);
        bool GetPlayerGroupAndGUIDByName(const char* cname, Player*& player, Group*& group, ObjectGuid& guid, bool offline = false);
        std::string extractPlayerNameFromLink(char* text);
        // select by arg (name/link) or in-game selection online/offline player or self if a creature is selected
        bool extractPlayerTarget(char* args, Player** player, ObjectGuid* player_guid = nullptr, std::string* player_name = nullptr);

        std::string playerLink(std::string const& name) const { return m_session ? "|cffffffff|Hplayer:"+name+"|h["+name+"]|h|r" : name; }
        std::string GetNameLink(Player* chr) const;

        GameObject* GetNearbyGameObject();
        GameObject* GetObjectGlobalyWithGuidOrNearWithDbGuid(ObjectGuid::LowType lowguid, uint32 entry);
        bool HasSentErrorMessage() const { return sentErrorMessage; }
        void SetSentErrorMessage(bool val){ sentErrorMessage = val; }

        bool ShowHelpForCommand(std::vector<ChatCommand> const& table, const char* cmd);
    protected:
        explicit ChatHandler() : m_session(nullptr), sentErrorMessage(false) { }     // for CLI subclass
        static bool SetDataForCommandInTable(std::vector<ChatCommand>& table, const char* text, uint32 permission, std::string const& help, std::string const& fullcommand);
        bool ExecuteCommandInTable(std::vector<ChatCommand> const& table, const char* text, std::string const& fullcmd);
        bool ShowHelpForSubCommands(std::vector<ChatCommand> const& table, char const* cmd, char const* subcmd);

    private:
        WorldSession* m_session;                           // != nullptr for chat command call and nullptr for CLI command

        // common global flag
        bool sentErrorMessage;
};

class TC_GAME_API CliHandler : public ChatHandler
{
    public:
        typedef void Print(void*, char const*);
        explicit CliHandler(void* callbackArg, Print* zprint) : m_callbackArg(callbackArg), m_print(zprint) { }

        // overwrite functions
        char const* GetTrinityString(uint32 entry) const override;
        bool isAvailable(ChatCommand const& cmd) const override;
        bool HasPermission(uint32 /*permission*/) const override { return true; }
        void SendSysMessage(const char *str, bool escapeCharacters) override;
        std::string GetNameLink() const override;
        bool needReportToTarget(Player* chr) const override;
        LocaleConstant GetSessionDbcLocale() const override;
        int GetSessionDbLocaleIndex() const override;

    private:
        void* m_callbackArg;
        Print* m_print;
};

#endif