#include "app.hpp"
#include "src/global-coords.hpp"
#include "shaders/tile.hpp"
#include "floormat/main.hpp"

namespace floormat {

void app::do_camera(float dt)
{
    if (keys[key::camera_reset])
    {
        reset_camera_offset();
        do_mouse_move();
    }
    else
    {
        Vector2d dir{};

        if (keys[key::camera_up])
            dir += Vector2d{0, -1};
        else if (keys[key::camera_down])
            dir += Vector2d{0,  1};
        if (keys[key::camera_left])
            dir += Vector2d{-1, 0};
        else if (keys[key::camera_right])
            dir += Vector2d{1,  0};

        if (dir != Vector2d{})
        {
            auto& shader = M->shader();
            const auto sz = M->window_size();
            constexpr double screens_per_second = 0.75;

            const double pixels_per_second = sz.length() / screens_per_second;
            auto camera_offset = shader.camera_offset();
            const auto max_camera_offset = Vector2d(sz * 10);

            camera_offset -= dir.normalized() * (double)dt * pixels_per_second;
            camera_offset[0] = std::clamp(camera_offset[0], -max_camera_offset[0], max_camera_offset[0]);
            camera_offset[1] = std::clamp(camera_offset[1], -max_camera_offset[1], max_camera_offset[1]);

            shader.set_camera_offset(camera_offset);

            update_cursor_tile(cursor.pixel);
            do_mouse_move();
        }
    }
}

void app::reset_camera_offset()
{
    constexpr Vector3d size = TILE_MAX_DIM20d*dTILE_SIZE*-.5;
    constexpr auto projected = tile_shader::project(size);
    M->shader().set_camera_offset(projected);
    update_cursor_tile(cursor.pixel);
}

void app::update_cursor_tile(const std::optional<Vector2i>& pixel)
{
    cursor.pixel = pixel;
    if (pixel)
        cursor.tile = M->pixel_to_tile(Vector2d{*pixel});
    else
        cursor.tile = std::nullopt;
}

} // namespace floormat