//---
// map: Dynamic level models
//
// This module provides dynamic maps as they are used during games. This
// includes objects being activated and their current state, doors being
// opened, crates being blown up, you name it. But not moving entities.
//---

#pragma once

#include "fixed.h"
#include "map.h"
#include "geometry.h"

#include <gint/display.h>

#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>

//---
// Tileset
//---

typedef struct
{
    /* Rendering plane */
    uint8_t plane;
    /* Length of animation cycle. This is only defined for the first tile of
       each cycle, because the cycle can use the same tile several times. If
       anim_length=0 there is no animation; anim_length=1 is useless. */
    uint8_t anim_length;
    /* Index in the tileset's animation array where this tile's animation cycle
       starts; it spans the range [anim_start .. anim_start+anim_length). */
    uint8_t anim_start;
    /* Hitbox. TODO: Allow any collision rectangle for tiles, for decor */
    bool solid;

} tile_info_t;

typedef struct
{
    /* ID of the tile visible during this frame */
    uint16_t tile_id;
    /* Duration before next frame, in ms */
    uint16_t duration_ms;

} tile_animation_frame_t;

typedef struct
{
    int width, height;
    bopti_image_t const *sheet;

    /* Tile information */
    tile_info_t *tiles;

    /* Animations */
    tile_animation_frame_t *anim;

} tileset_t;

/* Shape for a tile; this lives in a coordinate system whose (0,0) ends up at
   the middle of the tile in the map space (which is a point with half-integer
   coordinates) */
rect tile_shape(tileset_t const *tileset, int id);

//---
// Tiles
//---

typedef struct
{
    /* Base layer: floor/wall pattern */
    uint8_t base;
    /* Decoration layer */
    uint8_t decor;

} map_cell_t;

//---
// Map grid, tiles location in space, and entities
//---

typedef struct
{
    /* Dimensions, columns are 0 to width-1, rows are 0 to height-1 */
    uint16_t width, height;
    /* Tileset base (first layer), tileset decor (second layer) */
    tileset_t *tileset;
    /* All cells */
    map_cell_t *cells;

} map_t;

/* Get a pointer to the cell at (x,y) in map; NULL if out of bounds. */
map_cell_t *map_cell(map_t const *m, int x, int y);

/* Check whether a map cell is walkable, only accounting for full hitboxes. */
bool map_cell_walkable(map_t const *m, map_cell_t const *cell);

/* Check whether a hitbox collides with the map. */
bool map_collides(map_t const *m, rect hitbox);

/* Returns the new position of an object with a hitbox trying to move from
   [old_pos] to [new_pos]. */
vec2 map_move(map_t const *m, vec2 old_pos, vec2 new_pos, rect hitbox);