import { canvas } from './canvas'

class Viewport {
  constructor (x, y, scale = 1) {
    this.x = x
    this.y = y
    this.scale = scale
  }

  get width () {
    return canvas.width
  }

  get height () {
    return canvas.height
  }

  get adjustCentered () {
    return { x: Math.floor(this.x + this.width / 2), y: Math.floor(this.y + this.height / 2) }
  }

  chunkIn (size) {
    let adj = this.adjustCentered
    return { x: Math.floor(adj.x / size), y: Math.floor(adj.y / size) }
  }

  update (dt, world) {
    let full = world.chunkSize * world.tileSize
    if (this.x < 0) {
      this.x = 0
    } else if (this.x + this.width > world.width * full) {
      this.x = (full * world.width) - this.width
    }

    if (this.y < 0) {
      this.y = 0
    } else if (this.y + this.height > world.height * full) {
      this.y = (full * world.height) - this.height
    }
  }
}

export default Viewport