/*******************************
* B_spawn.c                    *
* Description:                 *
* various procedures that the  *
* bot need to work             *
*******************************/

#include <stdlib.h>

#include "doomtype.h"
#include "doomdef.h"
#include "doomstat.h"
#include "p_local.h"
#include "p_maputl.h"
#include "b_bot.h"
#include "g_game.h"
#include "m_random.h"
#include "r_sky.h"
#include "st_stuff.h"
#include "stats.h"
#include "i_system.h"
#include "s_sound.h"
#include "d_event.h"
#include "d_player.h"
#include "p_spec.h"

static FRandom pr_botdofire ("BotDoFire");


//Checks TRUE reachability from bot to a looker.
bool DBot::Reachable (AActor *rtarget)
{
	if (player->mo == rtarget)
		return false;

	if ((rtarget->Sector->ceilingplane.ZatPoint (rtarget) -
		 rtarget->Sector->floorplane.ZatPoint (rtarget))
		< player->mo->height) //Where rtarget is, player->mo can't be.
		return false;

	sector_t *last_s = player->mo->Sector;
	fixed_t last_z = last_s->floorplane.ZatPoint (player->mo);
	fixed_t estimated_dist = player->mo->AproxDistance(rtarget);
	bool reachable = true;

	FPathTraverse it(player->mo->X()+player->mo->velx, player->mo->Y()+player->mo->vely, rtarget->X(), rtarget->Y(), PT_ADDLINES|PT_ADDTHINGS);
	intercept_t *in;
	while ((in = it.Next()))
	{
		fixed_t hitx, hity;
		fixed_t frac;
		line_t *line;
		AActor *thing;
		fixed_t dist;
		sector_t *s;

		frac = in->frac - FixedDiv (4*FRACUNIT, MAX_TRAVERSE_DIST);
		dist = FixedMul (frac, MAX_TRAVERSE_DIST);

		hitx = it.Trace().x + FixedMul (player->mo->velx, frac);
		hity = it.Trace().y + FixedMul (player->mo->vely, frac);

		if (in->isaline)
		{
			line = in->d.line;

			if (!(line->flags & ML_TWOSIDED) || (line->flags & (ML_BLOCKING|ML_BLOCKEVERYTHING|ML_BLOCK_PLAYERS)))
			{
				return false; //Cannot continue.
			}
			else
			{
				//Determine if going to use backsector/frontsector.
				s = (line->backsector == last_s) ? line->frontsector : line->backsector;
				fixed_t ceilingheight = s->ceilingplane.ZatPoint (hitx, hity);
				fixed_t floorheight = s->floorplane.ZatPoint (hitx, hity);

				if (!bglobal.IsDangerous (s) &&		//Any nukage/lava?
					(floorheight <= (last_z+MAXMOVEHEIGHT)
					&& ((ceilingheight == floorheight && line->special)
						|| (ceilingheight - floorheight) >= player->mo->height))) //Does it fit?
				{
					last_z = floorheight;
					last_s = s;
					continue;
				}
				else
				{
					return false;
				}
			}
		}

		if (dist > estimated_dist)
		{
			return true;
		}

		thing = in->d.thing;
		if (thing == player->mo) //Can't reach self in this case.
			continue;
		if (thing == rtarget && (rtarget->Sector->floorplane.ZatPoint (rtarget) <= (last_z+MAXMOVEHEIGHT)))
		{
			return true;
		}

		reachable = false;
	}
	return reachable;
}

//doesnt check LOS, checks visibility with a set view angle.
//B_Checksight checks LOS (straight line)
//----------------------------------------------------------------------
//Check if mo1 has free line to mo2
//and if mo2 is within mo1 viewangle (vangle) given with normal degrees.
//if these conditions are true, the function returns true.
//GOOD TO KNOW is that the player's view angle
//in doom is 90 degrees infront.
bool DBot::Check_LOS (AActor *to, angle_t vangle)
{
	if (!P_CheckSight (player->mo, to, SF_SEEPASTBLOCKEVERYTHING))
		return false; // out of sight
	if (vangle == ANGLE_MAX)
		return true;
	if (vangle == 0)
		return false; //Looker seems to be blind.

	return absangle(player->mo->AngleTo(to) - player->mo->angle) <= vangle/2;
}

//-------------------------------------
//Bot_Dofire()
//-------------------------------------
//The bot will check if it's time to fire
//and do so if that is the case.
void DBot::Dofire (ticcmd_t *cmd)
{
	bool no_fire; //used to prevent bot from pumping rockets into nearby walls.
	int aiming_penalty=0; //For shooting at shading target, if screen is red, MAKEME: When screen red.
	int aiming_value; //The final aiming value.
	fixed_t dist;
	angle_t an;
	int m;

	if (!enemy || !(enemy->flags & MF_SHOOTABLE) || enemy->health <= 0)
		return;

	if (player->ReadyWeapon == NULL)
		return;

	if (player->damagecount > skill.isp)
	{
		first_shot = true;
		return;
	}

	//Reaction skill thing.
	if (first_shot &&
		!(player->ReadyWeapon->WeaponFlags & WIF_BOT_REACTION_SKILL_THING))
	{
		t_react = (100-skill.reaction+1)/((pr_botdofire()%3)+3);
	}
	first_shot = false;
	if (t_react)
		return;

	//MAKEME: Decrease the rocket suicides even more.

	no_fire = true;
	//Distance to enemy.
	dist = player->mo->AproxDistance(enemy, player->mo->velx - enemy->velx, player->mo->vely - enemy->vely);

	//FIRE EACH TYPE OF WEAPON DIFFERENT: Here should all the different weapons go.
	if (player->ReadyWeapon->WeaponFlags & WIF_MELEEWEAPON)
	{
		if ((player->ReadyWeapon->ProjectileType != NULL))
		{
			if (player->ReadyWeapon->CheckAmmo (AWeapon::PrimaryFire, false, true))
			{
				// This weapon can fire a projectile and has enough ammo to do so
				goto shootmissile;
			}
			else if (!(player->ReadyWeapon->WeaponFlags & WIF_AMMO_OPTIONAL))
			{
				// Ammo is required, so don't shoot. This is for weapons that shoot
				// missiles that die at close range, such as the powered-up Phoneix Rod.
				return;
			}
		}
		else
		{
			//*4 is for atmosphere,  the chainsaws sounding and all..
			no_fire = (dist > (MELEERANGE*4));
		}
	}
	else if (player->ReadyWeapon->WeaponFlags & WIF_BOT_BFG)
	{
		//MAKEME: This should be smarter.
		if ((pr_botdofire()%200)<=skill.reaction)
			if(Check_LOS(enemy, SHOOTFOV))
				no_fire = false;
	}
	else if (player->ReadyWeapon->ProjectileType != NULL)
	{
		if (player->ReadyWeapon->WeaponFlags & WIF_BOT_EXPLOSIVE)
		{
			//Special rules for RL
			an = FireRox (enemy, cmd);
			if(an)
			{
				angle = an;
				//have to be somewhat precise. to avoid suicide.
				if (absangle(angle - player->mo->angle) < 12*ANGLE_1)
				{
					t_rocket = 9;
					no_fire = false;
				}
			}
		}
		// prediction aiming
shootmissile:
		dist = player->mo->AproxDistance (enemy);
		m = dist / GetDefaultByType (player->ReadyWeapon->ProjectileType)->Speed;
		bglobal.SetBodyAt (enemy->X() + enemy->velx*m*2, enemy->Y() + enemy->vely*m*2, enemy->Z(), 1);
		angle = player->mo->AngleTo(bglobal.body1);
		if (Check_LOS (enemy, SHOOTFOV))
			no_fire = false;
	}
	else
	{
		//Other weapons, mostly instant hit stuff.
		angle = player->mo->AngleTo(enemy);
		aiming_penalty = 0;
		if (enemy->flags & MF_SHADOW)
			aiming_penalty += (pr_botdofire()%25)+10;
		if (enemy->Sector->lightlevel<WHATS_DARK/* && !(player->powers & PW_INFRARED)*/)
			aiming_penalty += pr_botdofire()%40;//Dark
		if (player->damagecount)
			aiming_penalty += player->damagecount; //Blood in face makes it hard to aim
		aiming_value = skill.aiming - aiming_penalty;
		if (aiming_value <= 0)
			aiming_value = 1;
		m = ((SHOOTFOV/2)-(aiming_value*SHOOTFOV/200)); //Higher skill is more accurate
		if (m <= 0)
			m = 1; //Prevents lock.

		if (m)
		{
			if (increase)
				angle += m;
			else
				angle -= m;
		}

		if (absangle(angle - player->mo->angle) < 4*ANGLE_1)
		{
			increase = !increase;
		}

		if (Check_LOS (enemy, (SHOOTFOV/2)))
			no_fire = false;
	}
	if (!no_fire) //If going to fire weapon
	{
		cmd->ucmd.buttons |= BT_ATTACK;
	}
	//Prevents bot from jerking, when firing automatic things with low skill.
}

bool FCajunMaster::IsLeader (player_t *player)
{
	for (int count = 0; count < MAXPLAYERS; count++)
	{
		if (players[count].Bot != NULL
			&& players[count].Bot->mate == player->mo)
		{
			return true;
		}
	}

	return false;
}

//This function is called every
//tick (for each bot) to set
//the mate (teammate coop mate).
AActor *DBot::Choose_Mate ()
{
	int count;
	fixed_t closest_dist, test;
	AActor *target;
	AActor *observer;

	//is mate alive?
	if (mate)
	{
		if (mate->health <= 0)
			mate = NULL;
		else
			last_mate = mate;
	}
	if (mate) //Still is..
		return mate;

	//Check old_mates status.
	if (last_mate)
		if (last_mate->health <= 0)
			last_mate = NULL;

	target = NULL;
	closest_dist = FIXED_MAX;
	if (bot_observer)
		observer = players[consoleplayer].mo;
	else
		observer = NULL;

	//Check for player friends
	for (count = 0; count < MAXPLAYERS; count++)
	{
		player_t *client = &players[count];

		if (playeringame[count]
			&& client->mo
			&& player->mo != client->mo
			&& (player->mo->IsTeammate (client->mo) || !deathmatch)
			&& client->mo->health > 0
			&& client->mo != observer
			&& ((player->mo->health/2) <= client->mo->health || !deathmatch)
			&& !bglobal.IsLeader(client)) //taken?
		{
			if (P_CheckSight (player->mo, client->mo, SF_IGNOREVISIBILITY))
			{
				test = client->mo->AproxDistance(player->mo);

				if (test < closest_dist)
				{
					closest_dist = test;
					target = client->mo;
				}
			}
		}
	}

/*
	//Make a introducing to mate.
	if(target && target!=last_mate)
	{
		if((P_Random()%(200*bglobal.botnum))<3)
		{
			chat = c_teamup;
			if(target->bot)
					strcpy(c_target, botsingame[target->bot_id]);
						else if(target->player)
					strcpy(c_target, player_names[target->play_id]);
		}
	}
*/

	return target;

}

//MAKEME: Make this a smart decision
AActor *DBot::Find_enemy ()
{
	int count;
	fixed_t closest_dist, temp; //To target.
	AActor *target;
	angle_t vangle;
	AActor *observer;

	if (!deathmatch)
	{ // [RH] Take advantage of the Heretic/Hexen code to be a little smarter
		return P_RoughMonsterSearch (player->mo, 20);
	}

	//Note: It's hard to ambush a bot who is not alone
	if (allround || mate)
		vangle = ANGLE_MAX;
	else
		vangle = ENEMY_SCAN_FOV;
	allround = false;

	target = NULL;
	closest_dist = FIXED_MAX;
	if (bot_observer)
		observer = players[consoleplayer].mo;
	else
		observer = NULL;

	for (count = 0; count < MAXPLAYERS; count++)
	{
		player_t *client = &players[count];
		if (playeringame[count]
			&& !player->mo->IsTeammate (client->mo)
			&& client->mo != observer
			&& client->mo->health > 0
			&& player->mo != client->mo)
		{
			if (Check_LOS (client->mo, vangle)) //Here's a strange one, when bot is standing still, the P_CheckSight within Check_LOS almost always returns false. tought it should be the same checksight as below but.. (below works) something must be fuckin wierd screded up. 
			//if(P_CheckSight(player->mo, players[count].mo))
			{
				temp = client->mo->AproxDistance(player->mo);

				//Too dark?
				if (temp > DARK_DIST &&
					client->mo->Sector->lightlevel < WHATS_DARK /*&&
					player->Powers & PW_INFRARED*/)
					continue;

				if (temp < closest_dist)
				{
					closest_dist = temp;
					target = client->mo;
				}
			}
		}
	}

	return target;
}



//Creates a temporary mobj (invisible) at the given location.
void FCajunMaster::SetBodyAt (fixed_t x, fixed_t y, fixed_t z, int hostnum)
{
	if (hostnum == 1)
	{
		if (body1)
		{
			body1->SetOrigin (x, y, z, false);
		}
		else
		{
			body1 = Spawn ("CajunBodyNode", x, y, z, NO_REPLACE);
		}
	}
	else if (hostnum == 2)
	{
		if (body2)
		{
			body2->SetOrigin (x, y, z, false);
		}
		else
		{
			body2 = Spawn ("CajunBodyNode", x, y, z, NO_REPLACE);
		}
	}
}

//------------------------------------------
//    FireRox()
//
//Returns NULL if shouldn't fire
//else an angle (in degrees) are given
//This function assumes actor->player->angle
//has been set an is the main aiming angle.


//Emulates missile travel. Returns distance travelled.
fixed_t FCajunMaster::FakeFire (AActor *source, AActor *dest, ticcmd_t *cmd)
{
	AActor *th = Spawn ("CajunTrace", source->PosPlusZ(4*8*FRACUNIT), NO_REPLACE);
	
	th->target = source;		// where it came from

	float speed = (float)th->Speed;

	fixedvec3 fixvel = source->Vec3To(dest);
	TVector3<double> velocity(fixvel.x, fixvel.y, fixvel.z);
	velocity.MakeUnit();
	th->velx = FLOAT2FIXED(velocity[0] * speed);
	th->vely = FLOAT2FIXED(velocity[1] * speed);
	th->velz = FLOAT2FIXED(velocity[2] * speed);

	fixed_t dist = 0;

	while (dist < SAFE_SELF_MISDIST)
	{
		dist += th->Speed;
		th->Move(th->velx, th->vely, th->velz);
		if (!CleanAhead (th, th->X(), th->Y(), cmd))
			break;
	}
	th->Destroy ();
	return dist;
}

angle_t DBot::FireRox (AActor *enemy, ticcmd_t *cmd)
{
	fixed_t dist;
	angle_t ang;
	AActor *actor;
	int m;

	bglobal.SetBodyAt (player->mo->X() + FixedMul(player->mo->velx, 5*FRACUNIT),
					   player->mo->Y() + FixedMul(player->mo->vely, 5*FRACUNIT),
					   player->mo->Z() + (player->mo->height / 2), 2);

	actor = bglobal.body2;

	dist = actor->AproxDistance (enemy);
	if (dist < SAFE_SELF_MISDIST)
		return 0;
	//Predict.
	m = (((dist+1)/FRACUNIT) / GetDefaultByName("Rocket")->Speed);

	bglobal.SetBodyAt (enemy->X() + FixedMul(enemy->velx, (m+2*FRACUNIT)),
					   enemy->Y() + FixedMul(enemy->vely, (m+2*FRACUNIT)), ONFLOORZ, 1);
	
	//try the predicted location
	if (P_CheckSight (actor, bglobal.body1, SF_IGNOREVISIBILITY)) //See the predicted location, so give a test missile
	{
		FCheckPosition tm;
		if (bglobal.SafeCheckPosition (player->mo, actor->X(), actor->Y(), tm))
		{
			if (bglobal.FakeFire (actor, bglobal.body1, cmd) >= SAFE_SELF_MISDIST)
			{
				ang = actor->AngleTo(bglobal.body1);
				return ang;
			}
		}
	}
	//Try fire straight.
	if (P_CheckSight (actor, enemy, 0))
	{
		if (bglobal.FakeFire (player->mo, enemy, cmd) >= SAFE_SELF_MISDIST)
		{
			ang = player->mo->AngleTo(enemy);
			return ang;
		}
	}
	return 0;
}

// [RH] We absolutely do not want to pick things up here. The bot code is
// executed apart from all the other simulation code, so we don't want it
// creating side-effects during gameplay.
bool FCajunMaster::SafeCheckPosition (AActor *actor, fixed_t x, fixed_t y, FCheckPosition &tm)
{
	ActorFlags savedFlags = actor->flags;
	actor->flags &= ~MF_PICKUP;
	bool res = P_CheckPosition (actor, x, y, tm);
	actor->flags = savedFlags;
	return res;
}

void FCajunMaster::StartTravel ()
{
	for (int i = 0; i < MAXPLAYERS; ++i)
	{
		if (players[i].Bot != NULL)
		{
			players[i].Bot->ChangeStatNum (STAT_TRAVELLING);
		}
	}
}

void FCajunMaster::FinishTravel ()
{
	for (int i = 0; i < MAXPLAYERS; ++i)
	{
		if (players[i].Bot != NULL)
		{
			players[i].Bot->ChangeStatNum (STAT_BOT);
		}
	}
}