#include "tilemap.hpp"

TileMap::TileMap(std::shared_ptr<TileSet> tileSet, std::vector<std::vector<int>> tiles)
{
    // resize the vertex array to fit the level size
    vertices.setPrimitiveType(sf::Quads);

    unsigned int size = tiles.size();
    vertices.resize(size * size * 4);

    // populate the vertex array, with one quad per tile
    for (unsigned int y = 0; y < size; ++y)
        for (unsigned int x = 0; x < size; ++x)
        {
            // get the current tile number
            int tileNumber = tiles[size - 1 - y][x];

            // TODO
            // Follow: https://www.sfml-dev.org/tutorials/2.5/graphics-vertex-array.php#example-tile-map
            // find its position in the tileset texture
            int tu = tileNumber % (tileset.getSize().y / tileSize.y);
            int tv = tileNumber / (tileset.getSize().y / tileSize.y);

            // get a pointer to the current tile's quad
            sf::Vertex *quad = &vertices[(y + x * width) * 4];

            // define its 4 corners
            quad[0].position = sf::Vector2f(y * tileSize.y, x * tileSize.y);
            quad[1].position = sf::Vector2f((y + 1) * tileSize.y, x * tileSize.y);
            quad[2].position = sf::Vector2f((y + 1) * tileSize.y, (x + 1) * tileSize.y);
            quad[3].position = sf::Vector2f(y * tileSize.y, (x + 1) * tileSize.y);

            // define its 4 texture coordinates
            quad[0].texCoords = sf::Vector2f(tu * tileSize.y, tv * tileSize.y);
            quad[1].texCoords = sf::Vector2f((tu + 1) * tileSize.y, tv * tileSize.y);
            quad[2].texCoords = sf::Vector2f((tu + 1) * tileSize.y, (tv + 1) * tileSize.y);
            quad[3].texCoords = sf::Vector2f(tu * tileSize.y, (tv + 1) * tileSize.y);
        }
}

void TileMap::draw(sf::RenderWindow *window)
{
    window->draw(*this);
}

void TileMap::draw(sf::RenderTarget &target, sf::RenderStates states) const
{
    // apply the transform
    // TODO? NEEDED?
//    states.transform *= getTransform();

    // apply the tileset texture
    states.texture = &tileMapTexture;

    // draw the vertex array
    target.draw(vertices, states);
}