import { PositionAndSizeProperty } from "../types"

function offsetSize(x: number, y: number, width: number, height: number) {
  return (old: PositionAndSizeProperty) => {
    const result: PositionAndSizeProperty = { ...old }
    result.x += x
    result.y += y
    result.width += width
    result.height += height
    return result
  }
}
const arrayKeys = ["ArrowUp", "ArrowDown", "ArrowLeft", "ArrowRight"] as const
type ArrayKey = (typeof arrayKeys)[number]

function checkArrayKey(key: string): key is ArrayKey {
  return (arrayKeys as unknown as string[]).indexOf(key) > -1
}

function getOptionType(ev: KeyboardEvent) {
  if (!ev.ctrlKey) {
    return "move"
  }

  if (ev.altKey) {
    return ev.shiftKey ? "shrinkBoth" : "shrink"
  } else {
    return ev.shiftKey ? "growBoth" : "grow"
  }
}
type DictItem = [ArrayKey, ReturnType<typeof getOptionType>, number, number, number, number]
const dict: DictItem[] = [
  ["ArrowLeft", "move", -1, 0, 0, 0],
  ["ArrowLeft", "grow", -1, 0, 1, 0],
  ["ArrowLeft", "growBoth", -1, 0, 2, 0],
  ["ArrowLeft", "shrink", 0, 0, -1, 0],
  ["ArrowLeft", "shrinkBoth", 1, 0, -2, 0],

  ["ArrowRight", "move", 1, 0, 0, 0],
  ["ArrowRight", "grow", 0, 0, 1, 0],
  ["ArrowRight", "growBoth", -1, 0, 2, 0],
  ["ArrowRight", "shrink", 1, 0, -1, 0],
  ["ArrowRight", "shrinkBoth", 1, 0, -2, 0],

  ["ArrowUp", "move", 0, -1, 0, 0],
  ["ArrowUp", "grow", 0, -1, 0, 1],
  ["ArrowUp", "growBoth", 0, -1, 0, 2],
  ["ArrowUp", "shrink", 0, 0, 0, -1],
  ["ArrowUp", "shrinkBoth", 0, 1, 0, -2],

  ["ArrowDown", "move", 0, 1, 0, 0],
  ["ArrowDown", "grow", 0, 0, 0, 1],
  ["ArrowDown", "growBoth", 0, -1, 0, 2],
  ["ArrowDown", "shrink", 0, 1, 0, -1],
  ["ArrowDown", "shrinkBoth", 0, 1, 0, -2],
]

export function moveAction(ev: KeyboardEvent) {
  const key = ev.key
  if (!checkArrayKey(key)) return undefined
  const opType = getOptionType(ev)
  const item = dict.find(i => i[0] === key && i[1] === opType)!
  return offsetSize(item[2], item[3], item[4], item[5])
}