use crate::{BACKGROUND_MAX_SIZE, EMPTY_TILE};
use glam::IVec2;

/// Tilemap which will be rendered on screen
pub struct Background {
    /// Tiles in idx, accessible via \[x\]\[y\], x and y 0..[BACKGROUND_MAX_SIZE]
    pub tiles: Vec<Vec<u16>>,
    /// Camera scroll (negative draw offset) for rendering
    pub scroll: IVec2,
    /// Size (used for rendering)
    pub size: IVec2,
    /// Are tiles indices half-tile indices?
    pub half_tile: bool,
    /// Is this background being displayed?
    pub active: bool,
}

impl Default for Background {
    fn default() -> Self {
        let row = vec![0u16; BACKGROUND_MAX_SIZE];
        let tiles = vec![row; BACKGROUND_MAX_SIZE];
        Self {
            tiles,
            scroll: IVec2::ZERO,
            half_tile: false,
            active: true,
            size: IVec2 { x: 19, y: 11 },
        }
    }
}

impl Background {
    /// Clears all tiles of given bg
    pub fn clear(&mut self) {
        self.fill(EMPTY_TILE);
    }

    /// Sets all tiles to val
    pub fn fill(&mut self, val: u16) {
        for x in 0..BACKGROUND_MAX_SIZE {
            for y in 0..BACKGROUND_MAX_SIZE {
                self.tiles[x][y] = val;
            }
        }
    }
}