/*
  Copyright (C) 2010-2011  Charles Pence <charles@charlespence.net>
  Copyright (C) 1996-1997  Id Software, Inc.

  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 3 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/>.
*/
// cvar.h

/*

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.
*/

void Cvar_RegisterVariable(const std::string &name, const std::string &value, bool archive = false);
// registers a new cvar with the given name, string, and archive value

void Cvar_Set(const std::string &var_name, const std::string &value);
// equivelant to "<name> <variable>" typed at the console

void Cvar_SetValue(const std::string &var_name, float value);
// expands value to a string and calls Cvar_Set

float Cvar_VariableValue(const std::string &var_name);
// returns 0 if not defined or non numeric

std::string Cvar_VariableString(const std::string &var_name);
// returns an empty string if not defined

std::string Cvar_CompleteVariable(const std::string &partial);
// attempts to match a partial variable name for command line completion
// returns NULL if nothing fits

qboolean Cvar_Command (void);
// 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 &fp);
// Writes lines containing "set variable value" for all variables
// with the archive flag set to true.
