/*
Copyright (C) 1996-2001 Id Software, Inc.
Copyright (C) 2002-2009 John Fitzgibbons and others
Copyright (C) 2010-2014 QuakeSpasm developers
Copyright (C) 2020-2021 Vittorio Romeo

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

#include <cstdio>

/*
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:

Cvar_RegisterVariable (&host_framerate);


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.

*/

#define CVAR_NONE 0
#define CVAR_ARCHIVE (1U << 0) // if set, causes it to be saved to config
#define CVAR_NOTIFY (1U << 1) // changes will be broadcasted to all players (q1)
#define CVAR_SERVERINFO \
    (1U << 2) // added to serverinfo will be sent to clients (q1/net_dgrm.c and
              // qwsv)
#define CVAR_USERINFO \
    (1U << 3) // added to userinfo, will be sent to server (qwcl)
#define CVAR_CHANGED (1U << 4)
#define CVAR_ROM (1U << 6)
#define CVAR_LOCKED (1U << 8)      // locked temporarily
#define CVAR_REGISTERED (1U << 10) // the var is added to the list of variables
#define CVAR_CALLBACK (1U << 16)   // var has a callback
#define CVAR_USERDEFINED \
    (1U << 17) // cvar was created by the user/mod, and needs to be saved a bit
               // differently. // QSS
#define CVAR_AUTOCVAR \
    (1U << 18) // cvar changes need to feed back to qc global changes. // QSS
#define CVAR_SETA (1U << 19) // cvar will be saved with seta. // QSS

typedef void (*cvarcallback_t)(struct cvar_t*);

struct cvar_t
{
    const char* name;
    const char* string;
    unsigned int flags;
    float value;
    const char*
        default_string; // johnfitz -- remember defaults for reset function
    cvarcallback_t callback;
    cvar_t* next;
};

void Cvar_RegisterVariable(cvar_t* variable);
// registers a cvar that already has the name, string, and optionally
// the archive elements set.

// QSS
cvar_t* Cvar_Create(const char* name, const char* value);
// creates+registers a cvar, otherwise just returns it.

void Cvar_SetCallback(cvar_t* var, cvarcallback_t func);
// set a callback function to the var

void Cvar_Set(const char* var_name, const char* value);
// equivelant to "<name> <variable>" typed at the console

void Cvar_SetValue(const char* var_name, const float value);
// expands value to a string and calls Cvar_Set

void Cvar_SetROM(const char* var_name, const char* value);
void Cvar_SetValueROM(const char* var_name, const float value);
// sets a CVAR_ROM variable from within the engine

void Cvar_SetQuick(cvar_t* var, const char* value);
void Cvar_SetValueQuick(cvar_t* var, const float value);
// these two accept a cvar pointer instead of a var name,
// but are otherwise identical to the "non-Quick" versions.
// the cvar MUST be registered.

float Cvar_VariableValue(const char* var_name);
// returns 0 if not defined or non numeric

const char* Cvar_VariableString(const char* var_name);
// returns an empty string if not defined

bool Cvar_Command();
// called by Cmd_ExecuteString when Cmd_Argv(0) doesn't match a known
// command.  Returns true if the command was a variable reference that
// was handled. (print or change)

void Cvar_WriteVariables(FILE* f);
// Writes lines containing "set variable value" for all variables
// with the CVAR_ARCHIVE flag set

cvar_t* Cvar_FindVar(const char* var_name);
cvar_t* Cvar_FindVarAfter(const char* prev_name, unsigned int with_flags);

void Cvar_LockVar(const char* var_name);
void Cvar_UnlockVar(const char* var_name);
void Cvar_UnlockAll();

void Cvar_Init();

const char* Cvar_CompleteVariable(const char* partial);
// attempts to match a partial variable name for command line completion
// returns nullptr if nothing fits

int Cvar_MakeHandle(const char* var_name);
float Cvar_GetValueFromHandle(const int handle);
void Cvar_SetValueFromHandle(const int handle, const float value);
void Cvar_ClearAllHandles();
