/*
	Generates (and regenerates) a freighter at the first object and
	instructs it to fly to each subsequent object until it goes
	back to the initial object, then repeats infinately.

	Usage: [-i <sec>] [-r <sec>] [-d <distance_ru>]
	       [-opm <opm_name>] [-n <name>] [-e <empire>]
	       <obj1_num> [obj#_num...]
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <math.h>
#include "../include/swserv-plugins.h"


typedef struct {

	time_t		next_update,	/* All these are in seconds */
			update_int,
			next_regenerate,
			regenerate_int;

	float		distance;	/* Intercept destination radius
					 * in real units */
	char		*opm_name;
	char		*name;
	char		*empire;

	int		obj_num;	/* The freighter object */

	int		*dest_obj_list;
	int		cur_dest_obj,	/* Index in dest_obj_list */
			ndest_objs;

} Core;
#define CORE(p)		((Core *)(p))


static void FreighterUpdate(SWServContext *ctx);
static void FreighterRegenerate(SWServContext *ctx);
static void CoreDelete(Core *core);


#define FREIGHTER_DEF_NAME			"DY300 Freighter"
#define FREIGHTER_DEF_OPM_NAME			"DY300 Freighter AI"
#define FREIGHTER_DEF_EMPIRE			"IND"

#define FREIGHTER_DEF_UPDATE_INT		3	/* In seconds */
#define FREIGHTER_DEF_REGENERATE_INT		(5 * 60)	/* In seconds */


#define USAGE_MESG	"\
Usage: [-i <sec>] [-r <sec>] [-d <distance_ru>]\
 <obj1_num> [obj#_num...]"


#define ATOI(s)         (((s) != NULL) ? atoi(s) : 0)
#define ATOL(s)         (((s) != NULL) ? atol(s) : 0)
#define ATOF(s)         (((s) != NULL) ? atof(s) : 0.0f)
#define STRDUP(s)       (((s) != NULL) ? strdup(s) : NULL)

#define MAX(a,b)        (((a) > (b)) ? (a) : (b))
#define MIN(a,b)        (((a) < (b)) ? (a) : (b))
#define CLIP(a,l,h)     (MIN(MAX((a),(l)),(h)))
#define STRLEN(s)       (((s) != NULL) ? (int)strlen(s) : 0)
#define STRISEMPTY(s)   (((s) != NULL) ? (*(s) == '\0') : 1)

#ifndef PI
# define PI		3.141592654
#endif


/*
 *	Creates or recreates the freighter at the first destination
 *	object as needed.
 *
 *	Checks if the freighter has reached the current destination
 *	object and if so then changes its intercept to go to the next
 *	destination object.
 */
static void FreighterUpdate(SWServContext *ctx)
{
	int ref_obj_num;
	xsw_object_struct *ref_obj;
	Core *core = CORE(SWServGetData(ctx));
	int obj_num = core->obj_num;
	xsw_object_struct *obj = SWServObjectGetPointer(ctx, obj_num);
	if(obj == NULL)
	    return;

	/* Get the current destination object */
	ref_obj_num = ((core->cur_dest_obj >= 0) &&
	    (core->cur_dest_obj < core->ndest_objs)) ?
	    core->dest_obj_list[core->cur_dest_obj] : -1;
	ref_obj = SWServObjectGetPointer(ctx, ref_obj_num);

	/* Current destination object no longer valid? */
	if(ref_obj == NULL)
	{
	    /* Set intercept to the next destination object */
	    core->cur_dest_obj++;
	    if(core->cur_dest_obj >= core->ndest_objs)
		core->cur_dest_obj = 0;

	    ref_obj_num = ((core->cur_dest_obj >= 0) && 
		(core->cur_dest_obj < core->ndest_objs)) ?    
		core->dest_obj_list[core->cur_dest_obj] : -1;

	    obj->intercepting_object = ref_obj_num;
	    obj->throttle = 0.0f;
	    obj->engine_state = SW_ENGINE_STATE_ON;

	    SWServObjectSyncConnections(ctx, obj_num, 0);

	    return;
	}

	/* Reached the current destination object? */
	if(SWServObjectsInRange(ctx, obj_num, ref_obj_num, core->distance))
	{
	    /* Set intercept to the next destination object */
	    core->cur_dest_obj++;
	    if(core->cur_dest_obj >= core->ndest_objs)
		core->cur_dest_obj = 0;

	    ref_obj_num = ((core->cur_dest_obj >= 0) &&
		(core->cur_dest_obj < core->ndest_objs)) ?
		core->dest_obj_list[core->cur_dest_obj] : -1;

	    obj->intercepting_object = ref_obj_num;
	    obj->throttle = 0.0f;
	    obj->engine_state = SW_ENGINE_STATE_ON;

	    /* Replenish antimatter */
	    obj->antimatter = obj->antimatter_max;

	    SWServObjectSyncConnections(ctx, obj_num, 0);

	    return;
	}

	if(obj->intercepting_object != ref_obj_num)
	    obj->intercepting_object = ref_obj_num;

	/* Adjust throttle and engine state */
	obj->throttle = 1.0f;
	if(obj->engine_state != SW_ENGINE_STATE_ON)
	    obj->engine_state = SW_ENGINE_STATE_ON;

	SWServObjectSyncConnections(ctx, obj_num, 0);
}

/*
 *	Regenerates the freighter as needed.
 */
static void FreighterRegenerate(SWServContext *ctx)
{
	int opm_num, obj_num, ref_obj_num;
	xsw_object_struct *obj, *ref_obj;
	Core *core = CORE(SWServGetData(ctx));

	/* Exists? */
	if(!SWServObjectIsGarbage(ctx, core->obj_num))
	    return;

	/* Get the first destination object */
	ref_obj_num = (core->ndest_objs > 0) ?
	    core->dest_obj_list[0] : -1;
	ref_obj = SWServObjectGetPointer(ctx, ref_obj_num);
	if(ref_obj == NULL)
	    return;

	/* Create a new freighter */
	core->obj_num = obj_num = SWServObjectCreate(
	    ctx, SW_OBJ_TYPE_CONTROLLED
	);
	obj = SWServObjectGetPointer(ctx, obj_num);
	if(obj == NULL)
	{
	    core->obj_num = -1;
	    return;
	}

	/* Get the model */
	opm_num = SWServOPMGetByName(ctx, core->opm_name);
	if(opm_num > -1)
	{
	    float c, theta;

	    /* Model the new freighter */
	    SWServOPMModelObject(ctx, opm_num, obj_num);
	    obj->owner = ref_obj->owner;
	    obj->sect_x = ref_obj->sect_x;   
	    obj->sect_y = ref_obj->sect_y;  
	    obj->sect_z = ref_obj->sect_z;

	    /* Initialize random number generator */
	    srand((unsigned int)core->next_regenerate);

	    c = (float)rand() / (float)RAND_MAX;
	    theta = 2.0 * PI * c;

	    obj->x = ref_obj->x + ((float)sin((double)theta) * core->distance);
	    obj->y = ref_obj->y + ((float)cos((double)theta) * core->distance);
	    obj->z = ref_obj->z;
	}

	if(!STRISEMPTY(core->name))
	{
	    strncpy(obj->name, core->name, sizeof(obj->name));
	    obj->name[sizeof(obj->name) - 1] = '\0';
	}
	if(!STRISEMPTY(core->empire))
	{
	    strncpy(obj->empire, core->empire, sizeof(obj->empire));
	    obj->empire[sizeof(obj->empire) - 1] = '\0';
	}

	/* Set initial intercept to the second destination object */
	ref_obj_num = (core->ndest_objs > 1) ?
	    core->dest_obj_list[1] : -1;
	obj->intercepting_object = ref_obj_num;

	core->cur_dest_obj = (core->ndest_objs > 1) ? 1 : 0;

	SWServObjectSyncConnections(ctx, obj_num, 1);
}

/*
 *	Deletes the core. 
 */
static void CoreDelete(Core *core)
{
	if(core == NULL)
	    return;

	free(core->opm_name);
	free(core->name);
	free(core->empire);
	free(core->dest_obj_list);
	free(core);
}


/*
 *	SWServ Plugin hail notify.
 */
SWPLUGIN_HAIL_NOTIFY_FUNCRTN SWPLUGIN_HAIL_NOTIFY_FUNC(
	int con_num,
	int obj_num,
	int tar_obj_num,
	int channel,
	const char *msg,
	SWServContext *ctx
)
{
	Core *core = CORE(SWServGetData(ctx));   
	float com_range = SWServSysparmGetF(ctx, "com_range");
	xsw_object_struct *obj, *tar_obj;

	if(core == NULL)
	    return;

	/* Ignore general hails and messages */
	if((tar_obj_num < 0) || (msg != NULL))
	    return;

	/* Skip itself */
	if(obj_num == tar_obj_num)
	    return;

	/* Did not hail our freighter? */
	if(tar_obj_num != core->obj_num)
	    return;

	obj = SWServObjectGetPointer(ctx, obj_num);
	tar_obj = SWServObjectGetPointer(ctx, tar_obj_num);
	if((obj == NULL) || (tar_obj == NULL))
	    return;

	/* Not in com range? */
	if(!SWServObjectsInRange(
	    ctx, obj_num, tar_obj_num,
	    com_range
	))
	    return;

	if((core->cur_dest_obj >= 0) &&
	   (core->cur_dest_obj < core->ndest_objs)
	)
	{
	    int dest_obj_num = core->dest_obj_list[core->cur_dest_obj];
	    xsw_object_struct *dest_obj = SWServObjectGetPointer(
		ctx, dest_obj_num
	    );
	    if(dest_obj != NULL)
	    {
		char *s = (char *)malloc(
		    STRLEN(tar_obj->name) +
		    STRLEN(dest_obj->name) + 80
		);
		sprintf(
		    s,
"This is %s enroute to %s.",
		    tar_obj->name,
		    dest_obj->name
		);
		SWServObjectSendMessage(
		    ctx,
		    tar_obj_num,
		    obj_num,
		    obj->com_channel,
		    s
		);
		free(s);
	    }
	}
}

/*
 *	SWServ Plugin destroy notify.
 */
SWPLUGIN_DESTROY_NOTIFY_FUNCRTN SWPLUGIN_DESTROY_NOTIFY_FUNC(
	int reason,
	int destroyed_obj_num,
	int destroyer_obj_num,
	int destroyer_obj_owner_num,
	SWServContext *ctx
)
{
	Core *core = CORE(SWServGetData(ctx));
	if(core == NULL)  
	    return;

	/* Our freighter was destroyed? */
	if(core->obj_num == destroyed_obj_num)
	{
	    /* Mark that our freighter was destroyed */
	    core->obj_num = -1;
	}
}


/*
 *	SWServ Plugin initialize.
 */
SWPLUGIN_INIT_FUNCRTN SWPLUGIN_INIT_FUNC(
	int argc, char **argv,
	int con_num,
	SWServContext *ctx
)
{
	int i;
	const char *arg;
	float distance = 2.0;
	Core *core = CORE(calloc(1, sizeof(Core)));

	if(core == NULL)
	    return(1);

	core->update_int = FREIGHTER_DEF_UPDATE_INT;
	core->regenerate_int = FREIGHTER_DEF_REGENERATE_INT;
	core->distance = distance;
	core->opm_name = STRDUP(FREIGHTER_DEF_OPM_NAME);
	core->name = STRDUP(FREIGHTER_DEF_NAME);
	core->empire = STRDUP(FREIGHTER_DEF_EMPIRE);
	core->obj_num = -1;
	core->dest_obj_list = NULL;
	core->cur_dest_obj = 0;
	core->ndest_objs = 0;

	for(i = 0; i < argc; i++)
	{
	    arg = argv[i];
	    if(arg == NULL)
		continue;

	    if(!strcasecmp(arg, "--help") ||
	       !strcasecmp(arg, "-help") ||
	       !strcasecmp(arg, "--h") ||
	       !strcasecmp(arg, "-h")   
	    )
	    {
		if(con_num > -1)
		    SWServConNotify(
			ctx, con_num, USAGE_MESG
		    );
		else
		    SWServPrint(
			ctx, USAGE_MESG "\n"
		    );
		CoreDelete(core);
	        return(1);
	    }
	    /* Update interval */
	    else if(!strcasecmp(arg, "--interval") ||
		    !strcasecmp(arg, "-interval") ||
		    !strcasecmp(arg, "--int") ||
		    !strcasecmp(arg, "-int") ||
		    !strcasecmp(arg, "-i")
	    )
	    {
		/* In seconds */
		i++;
		if(i < argc)
		    core->update_int = MAX(atol(argv[i]), 1l);
	    }
	    /* Regenerate interval */
	    else if(!strcasecmp(arg, "--regenerate") ||
		    !strcasecmp(arg, "-regenerate") ||
		    !strcasecmp(arg, "--r") ||
		    !strcasecmp(arg, "-r")
	    )
	    {
		/* In seconds */
		i++;
		if(i < argc)
		    core->regenerate_int = MAX(atol(argv[i]), 1l);
	    }
	    /* Distance */
	    else if(!strcasecmp(arg, "--distance") ||
		    !strcasecmp(arg, "-distance") ||
		    !strcasecmp(arg, "--d") ||
		    !strcasecmp(arg, "-d")
	    )
	    {
		/* In real units */
		i++;
		if(i < argc)
		    core->distance = MAX(atof(argv[i]), 0.0f);
	    }
	    /* Object Parameters Model */
	    else if(!strcasecmp(arg, "--opm") ||
		    !strcasecmp(arg, "-opm")
	    )
	    {
		i++;
		if(i < argc)
		{
		    free(core->opm_name);
		    core->opm_name = STRDUP(argv[i]);
		}
	    }
	    /* Name */
	    else if(!strcasecmp(arg, "--name") ||
		    !strcasecmp(arg, "-name") ||
		    !strcasecmp(arg, "--n") ||
		    !strcasecmp(arg, "-n")
	    )
	    {
		i++;
		if(i < argc)
		{
		    free(core->name);
		    core->name = STRDUP(argv[i]);
		}
	    }
	    /* Empire */
	    else if(!strcasecmp(arg, "--empire") ||
		    !strcasecmp(arg, "-empire") ||
		    !strcasecmp(arg, "--e") ||
		    !strcasecmp(arg, "-e")
	    )
	    {
		i++;
		if(i < argc)
		{
		    free(core->empire);
		    core->empire = STRDUP(argv[i]);
		}
	    }    
	    else
	    {
		/* All else assume object number */
		int n = core->ndest_objs;
		const int obj_num = ATOI(
		    (*arg == '#') ? (arg + 1) : arg
		);

		core->ndest_objs = n + 1;
		core->dest_obj_list = (int *)realloc(
		    core->dest_obj_list,
		    core->ndest_objs * sizeof(int)
		);
		core->dest_obj_list[n] = obj_num;
	    }
	}

	/* No destination objects spcified? */
	if(core->dest_obj_list == NULL)
	{
	    if(con_num > -1)
		SWServConNotify(
		    ctx, con_num, USAGE_MESG
		);
	    else
		SWServPrintError(
		    ctx, USAGE_MESG "\n"
		);
	    CoreDelete(core);
	    return(1);
	}

	/* Schedual initial updates */
	core->next_update = SWServCurrentTimeSeconds(ctx);
	core->next_regenerate = SWServCurrentTimeSeconds(ctx);

	SWServSetData(ctx, core);

	return(0);
}

/*
 *	SWServ Plugin manage.
 */
SWPLUGIN_MANAGE_FUNCRTN SWPLUGIN_MANAGE_FUNC(
	SWServContext *ctx
)
{
	Core *core = CORE(SWServGetData(ctx));   
	const time_t t = SWServCurrentTimeSeconds(ctx);

	if(core == NULL)
	    return(1);

	/* Time to update? */
	if(core->next_update <= t)
	{
	    FreighterUpdate(ctx);
	    core->next_update = t + core->update_int;
	}

	/* Time to regenerate? */
	if(core->next_regenerate <= t)
	{
	    FreighterRegenerate(ctx);
	    core->next_regenerate = t + core->regenerate_int;
	}

	return(0);
}

/*
 *	SWServ Plugin shutdown.
 */
SWPLUGIN_SHUTDOWN_FUNCRTN SWPLUGIN_SHUTDOWN_FUNC(
	SWServContext *ctx
)
{
	Core *core = CORE(SWServGetData(ctx));

	if(core == NULL)
	    return;

	/* Recycle our freighter as needed */
	if(core->obj_num > -1)
	{
	    SWServObjectRecycle(ctx, core->obj_num);
	    core->obj_num = -1;
	}

	CoreDelete(core);
	SWServSetData(ctx, NULL);
}