#include "physics.qh"
#include "input.qh"

.int disableclientprediction;

void sys_phys_simulate(entity this, float dt);

void sys_phys_update(entity this, float dt)
{
	sys_in_update(this, dt);

	sys_phys_fix(this, dt);
	if (sys_phys_override(this)) { return; } sys_phys_monitor(this);

	int buttons_prev = this.buttons_old;
	this.buttons_old = PHYS_INPUT_BUTTON_MASK(this);
	this.movement_old = this.movement;
	this.v_angle_old = this.v_angle;

	sys_phys_ai(this);

	sys_phys_pregame_hold(this);

	if (IS_SVQC) {
		if (PHYS_MOVETYPE(this) == MOVETYPE_NONE) { return; }
		// when we get here, disableclientprediction cannot be 2
		this.disableclientprediction = 0;
	}

	viewloc_PlayerPhysics(this);

	PM_check_frozen(this);

	PM_check_blocked(this);

	float maxspeed_mod = (!this.in_swamp) ? 1 : this.swamp_slowdown;  // cvar("g_balance_swamp_moverate");

// conveyors: first fix velocity
	if (this.conveyor.state) { this.velocity -= this.conveyor.movedir; }
	MUTATOR_CALLHOOK(PlayerPhysics, this);

	if (!IS_PLAYER(this)) {
		sys_phys_spectator_control(this);
		maxspeed_mod = this.spectatorspeed;
	}
	sys_phys_fixspeed(this, maxspeed_mod);

	if (IS_DEAD(this)) {
		// handle water here
		vector midpoint = ((this.absmin + this.absmax) * 0.5);
		if (pointcontents(midpoint) == CONTENT_WATER) {
			this.velocity = this.velocity * 0.5;

			// do we want this?
			// if(pointcontents(midpoint + '0 0 2') == CONTENT_WATER)
			// { this.velocity_z = 70; }
		}
		goto end;
	}

	if (IS_SVQC && !PHYS_FIXANGLE(this)) { this.angles = '0 1 0' * this.v_angle.y; }
	if (IS_PLAYER(this)) {
		if (IS_ONGROUND(this)) {
			PM_check_hitground(this);
			PM_Footsteps(this);
		} else if (IsFlying(this)) {
			this.wasFlying = true;
		}
		CheckPlayerJump(this);
	}

	if (this.flags & FL_WATERJUMP) {
		this.velocity_x = this.movedir.x;
		this.velocity_y = this.movedir.y;
		if (time > PHYS_TELEPORT_TIME(this)
		    || this.waterlevel == WATERLEVEL_NONE
		    || PHYS_WATERJUMP_TIME(this) <= 0
		   ) {
			this.flags &= ~FL_WATERJUMP;
			PHYS_TELEPORT_TIME(this) = 0;
			PHYS_WATERJUMP_TIME(this) = 0;
		}
	} else if (MUTATOR_CALLHOOK(PM_Physics, this, maxspeed_mod)) {
		// handled
	} else if (PHYS_MOVETYPE(this) == MOVETYPE_NOCLIP
	    || PHYS_MOVETYPE(this) == MOVETYPE_FLY
	    || PHYS_MOVETYPE(this) == MOVETYPE_FLY_WORLDONLY
	    || MUTATOR_CALLHOOK(IsFlying, this)) {
		this.com_phys_friction = PHYS_FRICTION(this);
		this.com_phys_vel_max = PHYS_MAXSPEED(this) * maxspeed_mod;
		this.com_phys_acc_rate = PHYS_ACCELERATE(this) * maxspeed_mod;
		sys_phys_simulate(this, dt);
	} else if (this.waterlevel >= WATERLEVEL_SWIMMING) {
		PM_swim(this, maxspeed_mod);
	} else if (time < this.ladder_time) {
		this.com_phys_friction = PHYS_FRICTION(this);
		this.com_phys_vel_max = PHYS_MAXSPEED(this) * maxspeed_mod;
		this.com_phys_acc_rate = PHYS_ACCELERATE(this) * maxspeed_mod;
		this.com_phys_gravity = '0 0 -1' * PHYS_GRAVITY(this) * dt;
		if (PHYS_ENTGRAVITY(this)) { this.com_phys_gravity *= PHYS_ENTGRAVITY(this); }
		this.com_phys_ladder = true;
		sys_phys_simulate(this, dt);
		this.com_phys_ladder = false;
		this.com_phys_gravity = '0 0 0';
	} else if (ITEMS_STAT(this) & IT_USING_JETPACK) {
		PM_jetpack(this, maxspeed_mod);
	} else if (IS_ONGROUND(this)) {
		if (!WAS_ONGROUND(this)) {
			emit(phys_land, this);
			if (this.lastground < time - 0.3) {
				this.velocity *= (1 - PHYS_FRICTION_ONLAND(this));
			}
		}
		PM_walk(this, maxspeed_mod);
	} else {
		PM_air(this, buttons_prev, maxspeed_mod);
	}

	LABEL(end)
	if (IS_ONGROUND(this)) { this.lastground = time; }
// conveyors: then break velocity again
	if (this.conveyor.state) { this.velocity += this.conveyor.movedir; }
	this.lastflags = this.flags;

	this.lastclassname = this.classname;
}

void sys_phys_simulate(entity this, float dt)
{
	// noclipping
	// flying
	// on a spawnfunc_func_ladder
	// swimming in spawnfunc_func_water
	UNSET_ONGROUND(this);

	float g = -this.com_phys_gravity.z;
	if (GAMEPLAYFIX_GRAVITYUNAFFECTEDBYTICRATE) {
		g *= 0.5;
		this.velocity_z += g;
	}
	this.velocity = this.velocity * (1 - dt * this.com_phys_friction);
	this.velocity_z += g;

	makevectors(this.v_angle);
	// wishvel = v_forward * this.movement.x + v_right * this.movement.y + v_up * this.movement.z;
	vector wishvel = v_forward * this.movement.x
	    + v_right * this.movement.y
	    + '0 0 1' * this.movement.z;
	if (this.com_phys_ladder) {
		if (this.viewloc) {
			wishvel.z = this.oldmovement.x;
		}
		if (this.ladder_entity.classname == "func_water") {
			float f = vlen(wishvel);
			if (f > this.ladder_entity.speed) {
				wishvel *= (this.ladder_entity.speed / f);
			}

			this.watertype = this.ladder_entity.skin;
			f = this.ladder_entity.origin_z + this.ladder_entity.maxs_z;
			if ((this.origin_z + this.view_ofs_z) < f) {
				this.waterlevel = WATERLEVEL_SUBMERGED;
			} else if ((this.origin_z + (this.mins_z + this.maxs_z) * 0.5) < f) {
				this.waterlevel = WATERLEVEL_SWIMMING;
			} else if ((this.origin_z + this.mins_z + 1) < f) {
				this.waterlevel = WATERLEVEL_WETFEET;
			} else {
				this.waterlevel = WATERLEVEL_NONE;
				this.watertype = CONTENT_EMPTY;
			}
		}
	}
	// acceleration
	vector wishdir = normalize(wishvel);
	float wishspeed = min(vlen(wishvel), this.com_phys_vel_max);
	if (IS_CSQC || time >= PHYS_TELEPORT_TIME(this)) {
		PM_Accelerate(this, wishdir, wishspeed, wishspeed, this.com_phys_acc_rate, 1, 0, 0, 0);
	}
	PM_ClientMovement_Move(this);
}