#include "sprite.h"

#include <assert.h>
#include <stdlib.h>

#include "raylib.h"
#include "raymath.h"

Sprite* sprite_from_texture(Texture2D tex,
                            Vector2* anchor,
                            Rectangle* source,
                            Color* color,
                            Arena* arena)
{
    Sprite* sprite = arena_alloc(arena, sizeof(Sprite), sizeof(Sprite));
    if (!sprite) abort();

    sprite->tex = tex;

    sprite->source =
        source != NULL
            ? *source
            : (Rectangle){0, 0, sprite->tex.width, sprite->tex.height};

    sprite->anchor = anchor != NULL ? *anchor
                                    : (Vector2){sprite->source.width / 2.0f,
                                                sprite->source.height / 2.0f};

    sprite->color = color != NULL ? *color : (Color){26, 164, 98, 255};

    sprite->animation = NULL;

    return sprite;
}

Sprite* sprite_new(const char* path,
                   Vector2* anchor,
                   Rectangle* source,
                   Color* color,
                   Arena* arena,
                   TextureManager* tm)
{
    assert(path && "path must not be empty");

    Texture2D tex = tm_load_texture(tm, path);
    return sprite_from_texture(tex, anchor, source, color, arena);
}

void sprite_draw(Sprite* s, Vector2 pos)
{
    Rectangle source = s->source;

    // update source rect if sprite has animation
    if (s->animation) {
        source.x = source.width * (float)s->animation->current_frame;
    }

    DrawTextureRec(s->tex, source, Vector2Subtract(pos, s->anchor), s->color);
}

//
// Animation System
//
void animation_update(Animation* a, float dt)
{
    a->current_time += dt;

    if (a->current_time >= 1.0f / a->fps) {
        a->current_time = 0;
        a->current_frame++;

        if (a->current_frame >= a->frame_count) {
            a->current_frame = 0;
        }
    }
}