/*
   base/ship.cc
   This file is part of the Osirion project and is distributed under 
   the terms and conditions of the GNU General Public License version 2 
*/

#include <cmath>
#include <iostream>

#include "auxiliary/functions.h"
#include "core/gameserver.h"
#include "core/entity.h"
#include "base/game.h"
#include "base/ship.h"
#include "math/functions.h"



using math::degrees360f;
using math::degrees180f;

namespace game {

const float 		MIN_DELTA = 0.000001f;

Ship::Ship(core::Player *owner, ShipModel *shipmodel) :
	core::EntityControlable(owner, ship_enttype),
	PhysicsBody(this)
{
	set_modelname(shipmodel->modelname());
	set_name(shipmodel->name());

	std::string str(aux::text_strip(owner->name()));
	aux::to_label(str);
	set_label(str);

	entity_moduletypeid = ship_enttype;

	entity_color = owner->color();
	entity_color_second = owner->color_second();

	ship_shipmodel = shipmodel;
	ship_jumpdrive = shipmodel->shipmodel_jumpdrive;
	
	ship_impulsedrive_timer = 0;
	ship_jumpdrive_timer = 0;
	ship_jumpdepart = 0;

	reset();
}

Ship::~Ship() 
{
	shutdown_physics();
}

void Ship::reset()
{
	current_target_direction = 0.0f;
	current_target_pitch = 0.0f;;
	current_target_roll = 0.0f;
	current_target_strafe = 0.0f;
	current_target_afterburner = 0.0f;
}
void Ship::func_impulse()
{
	if (entity_state == core::Entity::Impulse) {
		entity_state = core::Entity::Normal;
		target_thrust = 1.0f;
		entity_thrust = 1.0f;

	} else if (entity_state == core::Entity::ImpulseInitiate) {
		entity_state = core::Entity::Normal;
	
	} else if (entity_state != core::Entity::Normal) {
		return;
	
	} else { 
		if (entity_state == core::Entity::JumpInitiate) {
			ship_jumpdrive_timer = 0;
			entity_timer = 0;
		}
	
		entity_state = core::Entity::ImpulseInitiate;
		if (Game::g_devel->value()) {
			entity_timer = 0;
		} else {
			entity_timer = 3;
		}
		ship_impulsedrive_timer = core::server()->time();
		entity_dirty = true;
	}

	entity_dirty = true;
}

void Ship::initiate_jump(JumpPoint *depart)
{
	ship_jumpdepart = 0;

	if (!depart)
		return;

	if (!depart->target())
		return;

	ship_jumpdepart = depart;
	entity_state = core::Entity::JumpInitiate;

	if (Game::g_devel->value()) {
		entity_timer = 0;
	} else {
		entity_timer = 8;
	}

	ship_jumpdrive_timer = core::server()->time();
	entity_dirty = true;
}

void Ship::func_jump(std::string const &args)
{
	if (entity_state == core::Entity::Docked) {
		return;
	}

	// devel mode provides instant jump access to arbitrary systems
	if (Game::g_devel->value() && (args.size())) {

		core::Zone *jumptargetzone = core::Zone::search(args);

		if (!jumptargetzone) {
			std::string helpstr;
			for (core::Zone::Registry::iterator it = core::Zone::registry().begin(); it != core::Zone::registry().end(); it++) {
				if (helpstr.size())
					helpstr.append("^N|^B");
				helpstr.append((*it).second->label());
			}
			owner()->send("Usage: jump [^B" + helpstr + "^N]");
			return;
		}
	
		if (jumptargetzone == zone()) {
			owner()->send("Already in the " + jumptargetzone->name());
			return;
		}
		
		owner()->send("Jumping to the " + jumptargetzone->name());
		set_zone(jumptargetzone);

		ship_jumpdrive_timer = 0;
		entity_timer = 0;
		entity_state = core::Entity::Jump;
		entity_dirty = true;
		return;

	} else {

		if (!jumpdrive() && !Game::g_devel->value()) {
			owner()->send("This ship is not equiped with a hyperspace drive!");
			return;

		} else 	if (entity_state == core::Entity::Jump) {
			return;

		} else if (entity_state == core::Entity::JumpInitiate) {
			owner()->send("Jump aborted, hyperspace drive deactivated");
			ship_jumpdrive_timer = 0;
			entity_timer = 0;
			entity_state = core::Entity::Normal;
			return;
		}
		initiate_jump(find_closest_jumppoint());
	}
}

JumpPoint * Ship::find_closest_jumppoint()
{
	// find closest jumpgate or jumppoint
	float d = -1;
	JumpPoint *jumppoint = 0;
	for (core::Zone::Content::iterator it = zone()->content().begin(); it != zone()->content().end(); it++) {
		core::Entity *entity = (*it);
		if ((entity->moduletype() == jumppoint_enttype) || (entity->moduletype() == jumpgate_enttype)) {
			JumpPoint *te = static_cast<JumpPoint *>(entity);
			float d1 = math::distance(location(), te->location());
			if ((d < 0) || (d1 < d)) {
				d = d1;
				jumppoint = te;
			}
		}
	}
	
	if (jumppoint && jumppoint->target()) {
		if (Game::g_jumppointrange->value() < d) {
			owner()->send("Jumppoint out of range!");
			return 0;
		} else {
			owner()->send("Jumping to the " + jumppoint->target()->zone()->name());
			return jumppoint;
		}
	} else {
		owner()->send("No jumppoints found!");
		return 0;
	}
	
	return 0;
}

void Ship::explode()
{
	set_state(core::Entity::Destroyed);
		
	target_thrust = 0;
	target_pitch = 0;
	target_roll = 0;
	target_direction = 0;
	target_afterburner = 0.0f;
	target_thrust = 0;
	entity_thrust = 0;

	if (owner()) {
		if (owner()->control() == this)
			owner()->set_view(this);
	}
};

void Ship::set_zone(core::Zone *zone)
{
	shutdown_physics();

	core::EntityControlable::set_zone(zone);

	if (owner() && (owner()->control() == (EntityControlable*) this))
		owner()->set_zone(zone);

	init_physics(radius());
}

void Ship::frame(float seconds) 
{
	float actual_maxspeed = ship_shipmodel->maxspeed();
	float actual_turnspeed = ship_shipmodel->turnspeed();
	float actual_acceleration = ship_shipmodel->acceleration();
	float actual_thrust = 0;

#ifndef HAVE_BULLET
	const float direction_change_speed = 2;
	float cosangle;					// cosine of an angle
	float angle;					// angle in radians	
	math::Vector3f n;				// normal of a plane
	math::Axis target_axis(entity_axis);		// target axis
#endif
	entity_movement = 0;

	/* -- update state ----------------------------------------- */

	// speed might be set to 0 on this update
	if (entity_speed != 0.0f)
		entity_dirty = true;

	if (entity_state == core::Entity::Docked) {

		target_thrust = 0;
		target_pitch = 0;
		target_roll = 0;
		target_direction = 0;
		target_afterburner = 0.0f;
		target_thrust = 0;
		
		entity_speed = 0;
		entity_thrust = 0;

	} else if (entity_state == core::Entity::JumpInitiate) {

		if (ship_jumpdrive_timer + 1.0f <= core::server()->time()) {
			entity_timer -= 1.0f;

			if (entity_timer <= 0) {
				if (ship_jumpdepart && ship_jumpdepart->target()) {
					set_state(core::Entity::Jump);
					entity_speed = Game::g_impulsespeed->value();
					if (ship_jumpdepart->moduletype() == jumpgate_enttype) {
						entity_axis.assign(ship_jumpdepart->target()->axis());
						entity_location.assign(ship_jumpdepart->target()->location());
						//entity_location += entity_axis.forward() * radius();
					} else {
						entity_location.assign(ship_jumpdepart->target()->location() + location() - ship_jumpdepart->location());
					}					
					set_zone(ship_jumpdepart->target()->zone());
					owner()->send("^BJumping to the " + ship_jumpdepart->target()->zone()->name());
				} else {
					set_state(core::Entity::Normal);
				}
				ship_jumpdrive_timer = 0;
				entity_timer = 0;
				
				entity_dirty = true;
				return;
			} else {
				ship_jumpdrive_timer = core::server()->time();
				entity_dirty = true;
			}
		}

		// control is disabled while the jumpdrive is activated
		target_thrust = 0;
		target_pitch = 0;
		target_roll = 0;
		target_direction = 0;
		target_afterburner = 0.0f;
		target_thrust = 0.1;

	} else if (entity_state == core::Entity::Jump) {

		// control is disabled while the jumpdrive is activated
		target_thrust = 0;
		target_pitch = 0;
		target_roll = 0;
		target_direction = 0;
		target_afterburner = 0.0f;
		target_thrust = 0;

		// FIXME 5 second cooldown
		entity_state =  core::Entity::Normal;

		entity_dirty = true;

		if (owner() && owner()->view() && owner()->control() == (EntityControlable*) this)
			owner()->set_view(0);

		return;

	} else if (entity_state == core::Entity::ImpulseInitiate) {

		if (ship_impulsedrive_timer + 1.0f <= core::server()->time()) {
			entity_timer -= 1.0f;

			if (entity_timer <= 0) {
				actual_maxspeed = Game::g_impulsespeed->value();
				actual_acceleration = Game::g_impulseacceleration->value();
				entity_state = core::Entity::Impulse;
				entity_timer = 0;
				entity_dirty = true;
			} else {
				ship_impulsedrive_timer = core::server()->time();
				entity_dirty = true;
			}
		}

		// clamp input values
		target_thrust = 0.0f;
		math::clamp(target_pitch, -1.0f, 1.0f);
		math::clamp(target_roll, -1.0f, 1.0f);
		math::clamp(target_direction, -1.0f, 1.0f);
		math::clamp(target_afterburner, -1.0f, 1.0f);

		actual_turnspeed *= 0.5;

	} else if (entity_state == core::Entity::Impulse) {

		// clamp input values
		target_thrust = 0.0f;
		math::clamp(target_pitch, -1.0f, 1.0f);
		math::clamp(target_roll, -1.0f, 1.0f);
		math::clamp(target_direction, -1.0f, 1.0f);
		target_afterburner = 0.0f;

		actual_maxspeed = Game::g_impulsespeed->value();
		actual_acceleration = Game::g_impulseacceleration->value();
		actual_turnspeed *= 0.5;

	} else if (entity_state == core::Entity::Normal) {

		// clamp input values
		math::clamp(target_thrust, 0.0f, 1.0f);
		math::clamp(target_pitch, -1.0f, 1.0f);
		math::clamp(target_roll, -1.0f, 1.0f);
		math::clamp(target_direction, -1.0f, 1.0f);
		math::clamp(target_afterburner, -1.0f, 1.0f);

		if (speed() > actual_maxspeed * 1.15f) {
			actual_acceleration = Game::g_impulseacceleration->value();
			actual_turnspeed *= 0.5;
		}

	} else if (entity_state == core::Entity::Destroyed) {

		target_thrust = 0;
		target_pitch = 0;
		target_roll = 0;
		target_direction = 0;
		target_afterburner = 0.0f;
		target_thrust = 0;
		
		entity_thrust = 0;
	}

	// update afterburner
	if (current_target_afterburner < target_afterburner) {
		current_target_afterburner += 2.0f * seconds;
		if (current_target_afterburner > target_afterburner)
			current_target_afterburner = target_afterburner;
	} else if (current_target_afterburner > target_afterburner) {
		current_target_afterburner -= 2.0f * seconds;
		if (current_target_afterburner < target_afterburner)
			current_target_afterburner = target_afterburner;
	}

	// update thrust
	if (current_target_afterburner < 0.0f) {
		target_thrust = 0;
	}

	if (entity_thrust < target_thrust) {
		entity_thrust += seconds  * 0.5f;
		if (entity_thrust > target_thrust)
			entity_thrust = target_thrust;
	} else if (entity_thrust > target_thrust) {
		entity_thrust -= seconds * 0.5f;
		if (entity_thrust < target_thrust)
			entity_thrust = target_thrust;
	}
	math::clamp(entity_thrust, 0.0f, 1.0f);
	actual_thrust = entity_thrust + current_target_afterburner * 0.15f;
	if ((entity_state == core::Entity::ImpulseInitiate) || (entity_state == core::Entity::Impulse)) {
		actual_thrust = 1.0f;
	}
	
#ifndef HAVE_BULLET

	/* -- original frame --------------------------------------- */

	// update roll
	if (current_target_roll < target_roll) {
		current_target_roll += direction_change_speed * seconds;
		if (current_target_roll > target_roll)
			current_target_roll = target_roll;
	} else if (current_target_roll > target_roll) {
		current_target_roll -= direction_change_speed * seconds;
		if (current_target_roll < target_roll)
			current_target_roll = target_roll;
	}
	math::clamp(current_target_roll, -1.0f, 1.0f);

	if (fabs(current_target_roll) > MIN_DELTA) {	
		float roll_offset = seconds * current_target_roll;
		entity_axis.change_roll(actual_turnspeed * roll_offset);
	} else {
		current_target_roll = 0.0f;
	}

	// update target_axis direction	
	if (current_target_direction < target_direction) {
		current_target_direction += direction_change_speed * seconds;
		if (current_target_direction > target_direction) {
			current_target_direction = target_direction;
		}
	} else if (current_target_direction > target_direction) {
		current_target_direction -= direction_change_speed * seconds;
		if (current_target_direction < target_direction) {
			current_target_direction = target_direction;
		}
	}

	if (fabs(current_target_direction) > MIN_DELTA ) {
		math::clamp(current_target_direction, -1.0f, 1.0f);
		target_axis.change_direction(actual_turnspeed * current_target_direction);
	} else {
		current_target_direction = 0.0f;
	}

	if (current_target_pitch < target_pitch) {
		current_target_pitch += direction_change_speed * seconds;
		if (current_target_pitch > target_pitch)
			current_target_pitch = target_pitch;
	} else if (current_target_pitch > target_pitch) {
		current_target_pitch -= direction_change_speed * seconds;
		if (current_target_pitch < target_pitch)
			current_target_pitch = target_pitch;
	}
	
	if (fabs(current_target_pitch) > MIN_DELTA) {
		math::clamp(current_target_pitch, -1.0f, 1.0f);
		target_axis.change_pitch(actual_turnspeed * current_target_pitch);
	} else {
		current_target_pitch = 0.0f;
	}

	n.assign(math::crossproduct(entity_axis.forward(), target_axis.forward()));
	if (!(n.length() < MIN_DELTA)) {
		n.normalize();
		cosangle = math::dotproduct(entity_axis.forward(), target_axis.forward());
		angle = acos(cosangle) * seconds; // * 180.0f / M_PI;
		if (angle > MIN_DELTA)
			entity_axis.rotate(n, -angle);
	}

	// update speed
	if (entity_speed < actual_thrust * actual_maxspeed) {
		entity_speed += actual_acceleration * seconds;
		if (entity_speed > actual_thrust * actual_maxspeed) {
			entity_speed = actual_thrust * actual_maxspeed;
		}
	} else if(entity_speed > actual_thrust * actual_maxspeed) {
		entity_speed -= actual_acceleration * seconds;
		if (entity_speed < actual_thrust * actual_maxspeed) {
			entity_speed = actual_thrust * actual_maxspeed;
		}
	}

	// update strafe
	if (current_target_strafe < target_strafe) {
		current_target_strafe += 2.0f * seconds;
		if (current_target_strafe > target_strafe)
			current_target_strafe = target_strafe;
	} else if (current_target_strafe > target_strafe) {
		current_target_strafe -= 2.0f * seconds;
		if (current_target_strafe < target_strafe)
			current_target_strafe = target_strafe;
	}

	if (fabs(current_target_strafe) > MIN_DELTA) {
		entity_location += entity_axis.left() * (current_target_strafe * 0.15f * actual_maxspeed) * seconds;
	}

	if (entity_speed) {
		entity_location += entity_axis.forward() * entity_speed * seconds;
	}

#else /* #ifndef HAVE_BULLET */

	/* -- bullet frame ----------------------------------------- */

	// get entity speed from physics body
	btVector3 velocity(body()->getInterpolationLinearVelocity());
	entity_speed = velocity.length();

	// get physics body world transformation
	btTransform t;
	body()->getMotionState()->getWorldTransform(t);

	// get entity location from physics body
	btVector3 v(t.getOrigin());
	location().assign(v[0], v[1], v[2]);

	// apply engine trust to the body
	body()->applyCentralImpulse(to_btVector3(axis().forward() * actual_thrust * actual_acceleration * seconds * 20.0f));

#endif /* else #ifndef HAVE_BULLET */

	entity_movement = target_thrust;
	entity_movement = math::max(entity_movement, fabs(current_target_pitch));
	entity_movement = math::max(entity_movement, fabs(current_target_direction));
	entity_movement = math::max(entity_movement, fabs(current_target_roll));
	entity_movement = math::max(entity_movement, fabs(current_target_afterburner));
	entity_movement = math::max(entity_movement, fabs(current_target_strafe));

	if ((entity_movement  > 0)|| (entity_speed > 0)) {
		entity_dirty = true;
	}
}

} // namespace game