// Emacs style mode select -*- C++ -*-
//----------------------------------------------------------------------------
//
// Copyright(C) 2000 Simon Howard
//
// 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
//
//--------------------------------------------------------------------------
//
// scripting.
//
// delayed scripts, running scripts, console cmds etc in here
// the interface between FraggleScript and the rest of the game
//
// By Simon Howard
//
// This is just one vile piece of code with so many shortcuts and
// side effects that it should be banished in HELL forever!
//
//----------------------------------------------------------------------------
#include "r_local.h"
#include "t_script.h"
#include "p_lnspec.h"
#include "a_keys.h"
#include "d_player.h"
#include "p_spec.h"

IMPLEMENT_POINTY_CLASS(DRunningScript)
	DECLARE_POINTER(prev)
	DECLARE_POINTER(next)
	DECLARE_POINTER(trigger)
END_POINTERS

void clear_runningscripts();
extern TArray<void *> levelpointers;
bool HasScripts;

// the level script is just the stuff put in the wad,
// which the other scripts are derivatives of
script_t levelscript;

DRunningScript runningscripts;


//     FraggleScript action special
//

static int LS_FS_Execute (line_t *ln, AActor *it, bool backSide,
	int arg0, int arg1, int arg2, int arg3, int arg4)
// FS_Execute(script#,firstsideonly,lock,msgtype)
{
	if (arg1 && ln && backSide) return false;
	if (arg2!=0 && !P_CheckKeys(it, arg2, !!arg3)) return false;
	T_RunScript(arg0,it);
	return true;
}


//     T_Init()
//
//    called at program start

void T_Init()
{
	// I'd rather link the special here than make another source file depend on FS!
	LineSpecials[54]=LS_FS_Execute;
	init_variables();
	init_functions();
}

//     T_ClearScripts()
//
//      called at level start, clears all scripts
//		[CO] now it REALLY clears them!
//
void T_ClearScripts()
{
	DRunningScript *current;
	int i,j;
	void * p;

	// without the zone heap this has to be cleaned manually

	while (levelpointers.Pop(p)) free(p);

	// clear all old variables in the levelscript
	for(i=0; i<VARIABLESLOTS; i++)
    {
		svariable_t * var=levelscript.variables[i];
		while(var)
		{
			svariable_t *next = var->next;
			delete var;
			var = next;
		}
		levelscript.variables[i] = NULL;
    }
	for(i=0;i<SECTIONSLOTS;i++)
	{
		section_t * var=levelscript.sections[i];
		while(var)
		{
			section_t *next = var->next;
			delete var;
			var = next;
		}
		levelscript.sections[i] = NULL;
	}

    
	// abort all runningscripts and copy their data back to their owner
	// to make deletion easier
	current = runningscripts.next;
	while(current)
	{
		// copy out the script variables from the runningscript
		for(i=0; i<VARIABLESLOTS; i++) current->script->variables[i] = current->variables[i];
		
		DRunningScript *next = current->next;   // save before freeing
		current->Destroy();
		current = next;   // continue to next in chain
	}
	runningscripts.next=NULL;

	for(j=0;j<MAXSCRIPTS;j++) if (levelscript.children[j])
	{
		for(i=0; i<VARIABLESLOTS; i++)
		{
			svariable_t * var=levelscript.children[j]->variables[i];
			while(var)
			{
				svariable_t *next = var->next;
				delete var;
				var = next;
			}
		}
		for(i=0;i<SECTIONSLOTS;i++)
		{
			section_t * var=levelscript.children[j]->sections[i];
			while(var)
			{
				section_t *next = var->next;
				delete var;
				var = next;
			}
		}
		free(levelscript.children[j]->data);
		delete levelscript.children[j];
		levelscript.children[j]=NULL;
	}

	// clear the levelscript
	levelscript.data = (char *)realloc(levelscript.data, 5);  // empty data
	levelscript.data[0] = '\0'; // haleyjd 02/22/02: use '\0', not NULL
	
	levelscript.scriptnum = -1;
	levelscript.parent = &hub_script;
	
}

void T_PreprocessScripts()
{
	if (HasScripts)
	{
		// run the levelscript first
		// get the other scripts
		
		// levelscript started by player 0 'superplayer'
		levelscript.trigger = players[0].mo;
		
		preprocess(&levelscript);
		run_script(&levelscript);
	}
}

void T_RunScript(int snum, AActor * t_trigger)
{
	// [CO] It is far too dangerous to start the script right away.
	// Better queue it for execution for the next time
	// the runningscripts are checked.

	DRunningScript *runscr;
	script_t *script;
	int i;
	
	if(!HasScripts || snum < 0 || snum >= MAXSCRIPTS) return;
	script = levelscript.children[snum];
	if(!script)	return;
	
	runscr = new DRunningScript();
	runscr->script = script;
	runscr->savepoint = script->data; // start at beginning
	runscr->wait_type = wt_none;      // start straight away
	runscr->next = runningscripts.next;
	runscr->prev = &runningscripts;
	runscr->prev->next = runscr;
	if(runscr->next)
		runscr->next->prev = runscr;
	
	// save the script variables 
	for(i=0; i<VARIABLESLOTS; i++)
    {
		runscr->variables[i] = script->variables[i];
		
		// in case we are starting another current_script:
		// remove all the variables from the script variable list
		// we only start with the basic labels
		while(runscr->variables[i] && runscr->variables[i]->Type() != svt_label)
			runscr->variables[i] = runscr->variables[i]->next;
    }
	// copy trigger
	runscr->trigger = t_trigger;

}

// console scripting debugging commands



/************************
PAUSING SCRIPTS
************************/

void clear_runningscripts()
{
	DRunningScript *runscr, *next;
	
	runscr = runningscripts.next;
	
	// free the whole chain
	while(runscr)
    {
		next = runscr->next;
		runscr->Destroy();
		runscr = next;
    }
	runningscripts.next = NULL;
}



static bool wait_finished(DRunningScript *script)
{
	switch(script->wait_type)
    {
    case wt_none: return true;        // uh? hehe
    case wt_scriptwait:               // waiting for script to finish
		{
			DRunningScript *current;
			for(current = runningscripts.next; current; current = current->next)
			{
				if(current == script) continue;  // ignore this script
				if(current->script->scriptnum == script->wait_data)
					return false;        // script still running
			}
			return true;        // can continue now
		}
		
    case wt_delay:                          // just count down
		{
			return --script->wait_data <= 0;
		}
		
    case wt_tagwait:
		{
			int secnum = -1;
			
			while ((secnum = P_FindSectorFromTag(script->wait_data, secnum)) >= 0)
			{
				sector_t *sec = &sectors[secnum];
				if(sec->floordata || sec->ceilingdata || sec->lightingdata)
					return false;        // not finished
			}
			return true;
		}
		
    case wt_scriptwaitpre: // haleyjd - wait for script to start
		{
			DRunningScript *current;
			for(current=runningscripts.next; current; current=current->next)
			{
				if(current == script) continue;  // ignore this script
				if(current->script->scriptnum == script->wait_data)
					return true;        // script is now running
			}
			return false; // no running instances found
		}
		
    default: return true;
    }
	
	return false;
}

void T_DelayedScripts()
{
	DRunningScript *current, *next;
	int i;
	
	if(!HasScripts) return;       // no level scripts
    
	current = runningscripts.next;
    
	while(current)
	{
		if(wait_finished(current))
		{
			// copy out the script variables from the
			// runningscript
			
			for(i=0; i<VARIABLESLOTS; i++)
				current->script->variables[i] = current->variables[i];
			current->script->trigger = current->trigger; // copy trigger
			
			// unhook from chain 
			current->prev->next = current->next;
			if(current->next) current->next->prev = current->prev;
			next = current->next;   // save before freeing
			
			// continue the script
			continue_script(current->script, current->savepoint);
			
			// free
			current->Destroy();
		}
		else
			next = current->next;
		current = next;   // continue to next in chain
	}
}

static DRunningScript *T_SaveCurrentScript()
{
	DRunningScript *runscr;
	int i;
	
	runscr = new DRunningScript();
	runscr->script = current_script;
	runscr->savepoint = rover;
	
	// leave to other functions to set wait_type: default to wt_none
	runscr->wait_type = wt_none;
	
	// hook into chain at start
	
	runscr->next = runningscripts.next;
	runscr->prev = &runningscripts;
	runscr->prev->next = runscr;
	if(runscr->next)
		runscr->next->prev = runscr;
	
	// save the script variables 
	for(i=0; i<VARIABLESLOTS; i++)
    {
		runscr->variables[i] = current_script->variables[i];
		
		// remove all the variables from the script variable list
		// to prevent them being removed when the script stops
		
		while(current_script->variables[i] &&
			current_script->variables[i]->Type() != svt_label)
			current_script->variables[i] =
			current_script->variables[i]->next;
    }
	runscr->trigger = current_script->trigger;      // save trigger
	
	killscript = true;      // stop the script
	
	return runscr;
}

// script function

void SF_Wait()
{
	DRunningScript *runscr;
	
	if(t_argc != 1)
    {
		script_error("incorrect arguments to function\n");
		return;
    }
	
	runscr = T_SaveCurrentScript();
	
	runscr->wait_type = wt_delay;
	
	runscr->wait_data = (intvalue(t_argv[0]) * TICRATE) / 100;
}

// wait for sector with particular tag to stop moving
void SF_TagWait()
{
	DRunningScript *runscr;
	
	if(t_argc != 1)
    {
		script_error("incorrect arguments to function\n");
		return;
    }
	
	runscr = T_SaveCurrentScript();
	
	runscr->wait_type = wt_tagwait;
	runscr->wait_data = intvalue(t_argv[0]);
}

// wait for a script to finish
void SF_ScriptWait()
{
	DRunningScript *runscr;
	
	if(t_argc != 1)
    {
		script_error("insufficient arguments to function\n");
		return;
    }
	
	runscr = T_SaveCurrentScript();
	
	runscr->wait_type = wt_scriptwait;
	runscr->wait_data = intvalue(t_argv[0]);
}

// haleyjd 05/23/01: wait for a script to start (zdoom-inspired)
void SF_ScriptWaitPre()
{
	DRunningScript *runscr;
	
	if(t_argc != 1)
	{
		script_error("insufficient arguments to function\n");
		return;
	}
	
	runscr = T_SaveCurrentScript();
	runscr->wait_type = wt_scriptwaitpre;
	runscr->wait_data = intvalue(t_argv[0]);
}

extern AActor *trigger_obj;           // in t_func.c

void SF_StartScript()
{
	DRunningScript *runscr;
	script_t *script;
	int i, snum;
	
	if(t_argc != 1)
    {
		script_error("incorrect arguments to function\n");
		return;
    }
	
	snum = intvalue(t_argv[0]);
	
	if(snum < 0 || snum >= MAXSCRIPTS)
	{
		script_error("script number %d out of range\n",snum);
		return;
	}
	
	script = levelscript.children[snum];
	
	if(!script)
    {
		script_error("script %i not defined\n", snum);
    }
	
	runscr = new  DRunningScript();
	runscr->script = script;
	runscr->savepoint = script->data; // start at beginning
	runscr->wait_type = wt_none;      // start straight away
	
	// hook into chain at start
	
	// haleyjd: restructured
	runscr->next = runningscripts.next;
	runscr->prev = &runningscripts;
	runscr->prev->next = runscr;
	if(runscr->next)
		runscr->next->prev = runscr;
	
	// save the script variables 
	for(i=0; i<VARIABLESLOTS; i++)
    {
		runscr->variables[i] = script->variables[i];
		
		// in case we are starting another current_script:
		// remove all the variables from the script variable list
		// we only start with the basic labels
		while(runscr->variables[i] &&
			runscr->variables[i]->Type() != svt_label)
			runscr->variables[i] =
			runscr->variables[i]->next;
    }
	// copy trigger
	runscr->trigger = current_script->trigger;
}

void SF_ScriptRunning()
{
	DRunningScript *current;
	int snum = 0;
	
	if(t_argc < 1)
    {
		script_error("not enough arguments to function\n");
		return;
    }
	
	snum = intvalue(t_argv[0]);  
	
	for(current=runningscripts.next; current; current=current->next)
    {
		if(current->script->scriptnum == snum)
		{
			// script found so return
			t_return.type = svt_int;
			t_return.value.i = 1;
			return;
		}
    }
	
	// script not found
	t_return.type = svt_int;
	t_return.value.i = 0;
}


AActor *MobjForSvalue(svalue_t svalue)
{
	int intval;

	if(svalue.type == svt_mobj) 
	{
		return svalue.value.mobj;
	}
	else
	{
		// this requires some creativity. We use the intvalue
		// as the thing number of a thing in the level.
		intval = intvalue(svalue);
		
		if(intval < 0 || intval >= (int)SpawnedThings.Size())
		{ 
			return NULL;
		}
		return SpawnedThings[intval]->actor;
	}
}


/*********************
ADD SCRIPT
*********************/

// when the level is first loaded, all the
// scripts are simply stored in the levelscript.
// before the level starts, this script is
// preprocessed and run like any other. This allows
// the individual scripts to be derived from the
// levelscript. When the interpreter detects the
// 'script' keyword this function is called

// haleyjd: significant reformatting in 8-17

void spec_script()
{
	int scriptnum;
	int datasize;
	script_t *script;
	
	scriptnum = 0;
	
	if(!current_section)
    {
		script_error("need seperators for script\n");
		return;
    }
	
	// presume that the first token is "script"
	
	if(num_tokens < 2)
    {
		script_error("need script number\n");
		return;
    }
	
	scriptnum = intvalue(evaluate_expression(1, num_tokens-1));
	
	if(scriptnum < 0)
    {
		script_error("invalid script number\n");
		return;
    }
	
	script = new script_t;
	
	// add to scripts list of parent
	current_script->children[scriptnum] = script;
	
	// copy script data
	// workout script size: -2 to ignore { and }
	datasize = current_section->end - current_section->start - 2;
	
	// alloc extra 10 for safety
	script->data = (char *)malloc(datasize+10);
	
	// copy from parent script (levelscript) 
	// ignore first char which is {
	memcpy(script->data, current_section->start+1, datasize);
	
	// tack on a 0 to end the string
	script->data[datasize] = '\0';
	
	script->scriptnum = scriptnum;
	script->parent = current_script; // remember parent
	
	// preprocess the script now
	preprocess(script);
    
	// restore current_script: usefully stored in new script
	current_script = script->parent;
	
	// rover may also be changed, but is changed below anyway
	
	// we dont want to run the script, only add it
	// jump past the script in parsing
	
	rover = current_section->end + 1;
}


void T_FixScript(script_t * script,AActor * notold,AActor * old)
{
	if (script->trigger==old) script->trigger=notold;
}

// FraggleScript sucks so badly...
void T_FixPointers(DObject * notold ,DObject * old)
{
	// Don't bother with this shit when no FS present.
	if (HasScripts)
	{
		if (trigger_obj==old) trigger_obj=(AActor*)notold;
		T_FixScript(&levelscript,(AActor*)notold,(AActor*)old);
		T_FixScript(&global_script,(AActor*)notold,(AActor*)old);
		T_FixScript(&hub_script,(AActor*)notold,(AActor*)old);
	}
}
