#include "anim.h"
#include <gint/display.h>

/* List of animations (and directional animations). */
#define NORMAL_ANIM(name) \
    extern anim_frame_t name[];
#define DIRECTIONAL_ANIM(name) \
    extern anim_frame_t name ## _up[]; \
    extern anim_frame_t name ## _right[]; \
    extern anim_frame_t name ## _down[]; \
    extern anim_frame_t name ## _left[]; \
    anim_frame_t *name[4] = { \
        name ## _up, name ## _right, name ## _down, name ## _left };

#define ANIM_4DIRECTIONAL(prefix, suffix) \
    extern anim_frame_t prefix ## _up_    ## suffix[]; \
    extern anim_frame_t prefix ## _right_ ## suffix[]; \
    extern anim_frame_t prefix ## _down_  ## suffix[]; \
    extern anim_frame_t prefix ## _left_  ## suffix[]; \
    anim_frame_t *prefix ## _ ## suffix[4] = { \
        prefix ## _up_    ## suffix, \
        prefix ## _right_ ## suffix, \
        prefix ## _down_  ## suffix, \
        prefix ## _left_  ## suffix, \
    };

DIRECTIONAL_ANIM(anim_swing);
DIRECTIONAL_ANIM(anim_impale);

ANIM_4DIRECTIONAL(anims_player, Idle);
ANIM_4DIRECTIONAL(anims_player, Walking);
ANIM_4DIRECTIONAL(anims_player, Attack);
ANIM_4DIRECTIONAL(anims_player, Hit);

/* Animation functions. */

fixed_t (anim_duration)(anim_frame_t const *first_frame)
{
    anim_frame_t const *frame = first_frame;
    int ms = 0;
    int i = 0;

    while(frame == first_frame + i) {
        ms += frame->duration;
        frame = frame->next;
        i++;
    }

    return fix(ms) / 1000;
}

void anim_frame_render(int x, int y, anim_frame_t const *frame)
{
    if(!frame) return;
    dsubimage(x - frame->cx, y - frame->cy, frame->sheet,
        frame->x, frame->y, frame->w, frame->h, DIMAGE_NONE);
}

void anim_state_update(anim_state_t *state, fixed_t dt)
{
    if(!state->frame) return;

    state->elapsed += fround(dt * 1000);
    if(state->elapsed < state->frame->duration) return;

    /* Switch to next frame */
    state->elapsed = 0;
    state->frame = state->frame->next;
}