cursorscene.ts

namespace user_interface_base {
  import Screen = user_interface_base.Screen
  import Scene = user_interface_base.Scene


  /**
  * Top-level abstraction that is rendered on the screen.
  * It owns a Navigator, which has an group of organised buttons (such as a row or grid).
  * a Cursor which shows which button is currently selected, and a picker.
  * Defaults Navigator to NULL if it is not passed.
  */
  export class CursorScene extends Scene {
    navigator: INavigator
    public cursor: Cursor
    public picker: Picker

    constructor(app: AppInterface, navigator?: INavigator) {
      super(app, "scene")
      this.backgroundColor = 11

      if (navigator)
        this.navigator = navigator
      else
        this.navigator = null
    }

    public moveCursor(dir: CursorDir) {
      try {
        this.moveTo(this.cursor.move(dir))
      } catch (e) {
        if (dir === CursorDir.Up && e.kind === BACK_BUTTON_ERROR_KIND)
          this.back()
        else if (
          dir === CursorDir.Down &&
          e.kind === FORWARD_BUTTON_ERROR_KIND
        )
          return
        else throw e
      }
    }

    protected moveTo(target: Button) {
      if (!target) return
      this.cursor.moveTo(
        target.xfrm.worldPos,
        target.ariaId,
        target.bounds
      )
    }


    /**
    * Setup the controller buttons.
    * If you wish to override what the controller buttons do, then pass controlSetupFn.
    * overrides parent method, still invokes it.
    */
    startup() {
      super.startup()
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.right.id,
        () => this.moveCursor(CursorDir.Right)
      )
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.up.id,
        () => this.moveCursor(CursorDir.Up)
      )
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.down.id,
        () => this.moveCursor(CursorDir.Down)
      )
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.left.id,
        () => this.moveCursor(CursorDir.Left)
      )

      // click
      const click = () => this.cursor.click()
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.A.id,
        click
      )
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.A.id + keymap.PLAYER_OFFSET,
        click
      )
      context.onEvent(
        ControllerButtonEvent.Pressed,
        controller.B.id,
        () => this.back()
      )

      this.cursor = new Cursor()
      this.picker = new Picker(this.cursor)
      if (this.navigator == null)
        this.navigator = new RowNavigator()
      this.cursor.navigator = this.navigator
    }

    /**
    * What this does is specific to the Navigator.
    * The RowNavigator will make the Cursor hover over the first Button.
    */
    back() {
      if (!this.cursor.cancel()) this.moveCursor(CursorDir.Back)
    }


    protected handleClick(x: number, y: number) {
      const target = this.cursor.navigator.screenToButton(
        x - Screen.HALF_WIDTH,
        y - Screen.HALF_HEIGHT
      )
      if (target) {
        this.moveTo(target)
        target.click()
      } else if (this.picker.visible) {
        this.picker.hide()
      }
    }

    protected handleMove(x: number, y: number) {
      const btn = this.cursor.navigator.screenToButton(
        x - Screen.HALF_WIDTH,
        y - Screen.HALF_HEIGHT
      )
      if (btn) {
        const w = btn.xfrm.worldPos
        this.cursor.snapTo(w.x, w.y, btn.ariaId, btn.bounds)
        btn.reportAria(true)
      }
    }

        /* override */ shutdown() {
      this.navigator.clear()
    }

        /* override */ activate() {
      super.activate()
      const btn = this.navigator.initialCursor(0, 0)
      if (btn) {
        const w = btn.xfrm.worldPos
        this.cursor.snapTo(w.x, w.y, btn.ariaId, btn.bounds)
        btn.reportAria(true)
      }
    }

        /* override */ update() {
      this.cursor.update()
    }

        /* override */ draw() {
      this.picker.draw()
      this.cursor.draw()
    }
  }
}