//---
// particle: Lightweight, standalone component for particles
//
// This component if for basic visual particles with simple rendering. The
// particles can carry extra data and might be rendered above the rest of the
// scene.
//---

#pragma once

#include "comp/entity.h"
#include "fixed.h"

/* Particle types */
enum {
    PARTICLE_GENERIC = 0,
    PARTICLE_DAMAGE,
    PARTICLE_DASH,
    PARTICLE_HPBAR,
    PARTICLE_BUFF,
};

typedef struct
{
    /* Type of particle */
    uint8_t type;
    /* Plane of rendering */
    uint8_t plane;
    /* Whether the particle's position is bound to an entity, or absolute */
    bool bound_to_entity;

    /* Location on screen and in the air */
    union {
        struct { fixed_t x, y; };
        entity_t *bound_entity;
    };
    fixed_t z;
    /* Age (milliseconds) */
    int age;

    /* 8 bytes of data */
    union {
        /* Generic particles or with a lot of extra data */
        struct { void *data1, *data2; } GENERIC;
        /* PARTICLE_DAMAGE: Value and color (can be C_WHITE or C_RED only) */
        struct { int damage; uint16_t color; } DAMAGE;
        /* PARTICLE_DASH: No extra data */

        /* PARTICLE_HPBAR: Pointer to entity */
        struct { entity_t *entity; } HPBAR;
        /* PARTICLE_BUFF: Buff animation */
        struct { uint16_t color; } BUFF;
    };

} particle_t;

/* Make a damage particle for the specified target */
entity_t *particle_make_damage(entity_t *target, int damage, int color);

/* Make a dashing particle at the specified target's position */
entity_t *particle_make_dash(entity_t *target);

/* Make a buff particle of the specified color bound to the specified target */
entity_t *particle_make_buff(entity_t *target, int color);

/* Update time and layout for a particle (type-generic). */
bool particle_update(particle_t *p, fixed_t dt);

/* Render a particle through the map and camera. */
void particle_render(int x, int y, particle_t const *p);