/*
Copyright (C) 1996-2001 Id Software, Inc.
Copyright (C) 2002-2009 John Fitzgibbons and others
Copyright (C) 2010-2014 QuakeSpasm developers

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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/

#pragma once

/*
cvar_t variables are used to hold scalar or string variables that can
be changed or displayed at the console or prog code as well as accessed
directly in C code.

it is sufficient to initialize a cvar_t with just the first two fields,
or you can add a ,true flag for variables that you want saved to the
configuration file when the game is quit:

cvar_t	r_draworder = {"r_draworder","1"};
cvar_t	scr_screensize = {"screensize","1",true};

Cvars must be registered before use, or they will have a 0 value instead
of the float interpretation of the string.
Generally, all cvar_t declarations should be registered in the apropriate
init function before any console commands are executed:

host_framerate.inscribe();

C code usually just references a cvar in place:
if ( r_draworder.value )

It could optionally ask for the value to be looked up for a string name:
if (Cvar_VariableValue ("r_draworder"))

Interpreted prog code can access cvars with the cvar(name) or
cvar_set (name, value) internal functions:
teamplay = cvar("teamplay");
cvar_set ("registered", "1");

The user can access cvars from the console in two ways:
r_draworder		prints the current value
r_draworder 0		sets the current value to 0

Cvars are restricted from having the same names as commands to keep this
interface from being ambiguous.

*/

#include <map>
#include <optional>
#include <ranges>

#include "convar.hpp"

void Cvar_Init();

struct cvar_flags {
    bool archive{false};
    bool notify{false};
    bool server_info{false};
    bool user_info{false};
    bool changed{false};
    bool rom{false};
    bool locked{false};
    bool registered{false};
    bool callback{false};

    [[nodiscard]] bool matches_mask(const cvar_flags &rhs) const {
        return (!rhs.archive || this->archive) &&
               (!rhs.notify || this->notify) &&
               (!rhs.server_info || this->server_info) &&
               (!rhs.user_info || this->user_info) &&
               (!rhs.changed || this->changed) &&
               (!rhs.rom || this->rom) &&
               (!rhs.locked || this->locked) &&
               (!rhs.registered || this->registered) &&
               (!rhs.callback || this->callback);
    }
};

struct convar;

typedef void (*cvarcallback_t)(convar *);

using convar_view = std::ranges::elements_view<std::ranges::ref_view<std::map<std::string, convar *> >, 1>;

struct convar {
    std::string name{};
    const char *string{nullptr};
    cvar_flags flags{};
    float value{};
    const char *default_string{nullptr}; //johnfitz -- remember defaults for reset function
    cvarcallback_t callback{nullptr};

    convar(std::string_view name, const char *str);

    convar(std::string_view name, const char *str, cvar_flags flags);

    void inscribe();

    void set_callback(cvarcallback_t func);

    void set(const std::string &new_value);

    void set_value(float new_value);

    static std::optional<convar *> find_var(const std::string_view &desired);

    static std::optional<convar *> find_var_after(const std::optional<std::string> &prev_name,
                                                  std::optional<cvar_flags> with_flags);

    static void reset(const std::string &name);

    static void set(const std::string &name, const std::string &new_value);

    static void set_value(const std::string &name, float new_value);

    static std::optional<std::string_view> complete_variable(const std::string_view &partial);

    static std::optional<float> variable_value(const std::string_view &name);

    static std::optional<std::string> variable_string(const std::string_view &name);

    static void lock_var(const std::string_view &name);

    static void unlock_var(const std::string_view &name);

    static void unlock_all();

    static void set_rom(const std::string_view &name, std::string value);

    static void set_value_rom(const std::string_view &name, float value);

    static convar_view get_variables();
};

bool Cvar_Command(void);

void Cvar_WriteVariables(FILE *f);