// Copyright (c) 2022 Dominic Masters
// 
// This software is released under the MIT License.
// https://opensource.org/licenses/MIT

#pragma once
#include "dawnlibs.hpp"
#include "assert/assert.hpp"
#include "display/Texture.hpp"

namespace Dawn {
  struct Tile {
    glm::vec2 uv0;
    glm::vec2 uv1;
  };

  struct Tileset {
    public:
      std::vector<struct Tile> tiles;

      /**
       * Returns the tile at the given tile index.
       * 
       * @param tile Tile index to get.
       * @return Tile at that index.
       */
      struct Tile getTile(int32_t tile);

      /**
       * Returns the width of an individual tile.
       * 
       * @param tile The tile to get the width of.
       * @return The tile width.
       */
      virtual float_t getTileWidth(int32_t tile) = 0;

      /**
       * Returns the height of an individual tile.
       * 
       * @param tile The tile to get the height of.
       * @return The tile height.
       */
      virtual float_t getTileHeight(int32_t tile) = 0;
  };

  struct TilesetGrid : public Tileset{
    public:
      int32_t rows;
      int32_t columns;
      int32_t divX;
      int32_t divY;

      /**
       * Constructs a new Tileset Grid.
       */
      TilesetGrid();

      /**
       * Constructs a new Tileset Grid from a texture.
       * 
       * @param texture Texture to use.
       * @param columns Columns in the grid.
       * @param rows Rows in the grid.
       */
      TilesetGrid(Texture *texture, int32_t columns, int32_t rows);

      /**
       * Constructs a new Tileset Grid from a texture.
       * 
       * @param texture Texture to use.
       * @param columns Columns in the grid.
       * @param rows Rows in the grid.
       */
      TilesetGrid(Texture &texture, int32_t columns, int32_t rows);
    
      /**
       * Constructs a new Tileset Grid.
       * 
       * @param columns How many columns in the grid of tiles.
       * @param rows How many rows in the grid of tiles.
       * @param w Width of the grid.
       * @param h Height of te grid.
       * @param gapX Gap / Gutter between tiles.
       * @param gapY Gap / Gutter between tiles.
       * @param borderX Border at the edge of the grid before the first tiles.
       * @param borderY Border at the edge of the grid before the first tiles.
       */
      TilesetGrid(
        int32_t columns,
        int32_t rows,
        int32_t w,
        int32_t h,
        int32_t gapX,
        int32_t gapY,
        int32_t borderX,
        int32_t borderY
      );

      float_t getTileWidth(int32_t tile) override;
      float_t getTileHeight(int32_t tile) override;

      /**
       * Returns the tile at a given grid position.
       * 
       * @param column Column (0 indexed) to get the tile of.
       * @param row Row (0 indexed) to get the tile of.
       * @return Tile at this grid position.
       */
      struct Tile getTileFromGrid(int32_t column, int32_t row);
  };
}