import { Editor } from '@tiptap/core'
import { EditorState, Plugin, PluginKey } from 'prosemirror-state'
import { EditorView } from 'prosemirror-view'

interface BubbleMenuSettings {
  bottom: number;
  isActive: boolean;
  left: number;
  top: number;
}
interface BubbleMenuPluginOptions {
  editor: Editor;
  element: HTMLElement;
  keepInBounds: boolean;
  onUpdate(menu: BubbleMenuSettings): void;
}
type DOMRectSide = 'bottom' | 'left' | 'right' | 'top';

function textRange(node: Node, from?: number, to?: number) {
  const range = document.createRange()
  range.setEnd(
    node,
    typeof to === 'number' ? to : (node.nodeValue || '').length,
  )
  range.setStart(node, from || 0)
  return range
}

function singleRect(object: Range | Element, bias: number) {
  const rects = object.getClientRects()
  return !rects.length
    ? object.getBoundingClientRect()
    : rects[bias < 0 ? 0 : rects.length - 1]
}

function coordsAtPos(view: EditorView, pos: number, end = false) {
  const { node, offset } = view.domAtPos(pos) // view.docView.domFromPos(pos);
  let side: DOMRectSide | null = null
  let rect: DOMRect | null = null
  if (node.nodeType === 3) {
    const nodeValue = node.nodeValue || ''
    if (end && offset < nodeValue.length) {
      rect = singleRect(textRange(node, offset - 1, offset), -1)
      side = 'right'
    } else if (offset < nodeValue.length) {
      rect = singleRect(textRange(node, offset, offset + 1), -1)
      side = 'left'
    }
  } else if (node.firstChild) {
    if (offset < node.childNodes.length) {
      const child = node.childNodes[offset]
      rect = singleRect(
        child.nodeType === 3 ? textRange(child) : (child as Element),
        -1,
      )
      side = 'left'
    }
    if ((!rect || rect.top === rect.bottom) && offset) {
      const child = node.childNodes[offset - 1]
      rect = singleRect(
        child.nodeType === 3 ? textRange(child) : (child as Element),
        1,
      )
      side = 'right'
    }
  } else {
    const element = node as Element
    rect = element.getBoundingClientRect()
    side = 'left'
  }

  if (rect && side) {
    const x = rect[side]

    return {
      top: rect.top,
      bottom: rect.bottom,
      left: x,
      right: x,
    }
  }
  return {
    top: 0,
    bottom: 0,
    left: 0,
    right: 0,
  }
}

class Menu {
  public options: BubbleMenuPluginOptions;

  public editorView: EditorView;

  public isActive = false;

  public left = 0;

  public bottom = 0;

  public top = 0;

  public preventHide = false;

  constructor({
    options,
    editorView,
  }: {
    options: BubbleMenuPluginOptions;
    editorView: EditorView;
  }) {
    this.options = {
      ...{
        element: null,
        keepInBounds: true,
        onUpdate: () => false,
      },
      ...options,
    }
    this.editorView = editorView
    this.options.element.addEventListener('mousedown', this.mousedownHandler, {
      capture: true,
    })
    this.options.editor.on('focus', this.focusHandler)
    this.options.editor.on('blur', this.blurHandler)
  }

  mousedownHandler = () => {
    this.preventHide = true
  };

  focusHandler = () => {
    this.update(this.options.editor.view)
  };

  blurHandler = ({ event }: { event: FocusEvent }) => {
    if (this.preventHide) {
      this.preventHide = false
      return
    }

    this.hide(event)
  };

  update(view: EditorView, lastState?: EditorState) {
    const { state } = view

    if (view.composing) {
      return
    }

    if (
      lastState
      && lastState.doc.eq(state.doc)
      && lastState.selection.eq(state.selection)
    ) {
      return
    }

    if (state.selection.empty) {
      this.hide()
      return
    }

    const { from, to } = state.selection
    const start = coordsAtPos(view, from)
    const end = coordsAtPos(view, to, true)
    const parent = this.options.element.offsetParent

    if (!parent) {
      this.hide()
      return
    }

    const box = parent.getBoundingClientRect()
    const el = this.options.element.getBoundingClientRect()
    const left = (start.left + end.left) / 2 - box.left

    this.left = Math.round(
      this.options.keepInBounds
        ? Math.min(box.width - el.width / 2, Math.max(left, el.width / 2))
        : left,
    )
    this.bottom = Math.round(box.bottom - start.top)
    this.top = Math.round(end.bottom - box.top)
    this.isActive = true

    console.log({
      left: this.left,
      top: this.top,
    })

    this.sendUpdate()
  }

  sendUpdate() {
    this.options.onUpdate({
      isActive: this.isActive,
      left: this.left,
      bottom: this.bottom,
      top: this.top,
    })
  }

  hide(event?: FocusEvent) {
    if (
      event
      && event.relatedTarget
      && this.options.element.parentNode
      && this.options.element.parentNode.contains(event.relatedTarget as Node)
    ) {
      return
    }

    this.isActive = false
    this.sendUpdate()
  }

  destroy() {
    this.options.element.removeEventListener(
      'mousedown',
      this.mousedownHandler,
    )
    this.options.editor.off('focus', this.focusHandler)
    this.options.editor.off('blur', this.blurHandler)
  }
}

const BubbleMenuPlugin = (options: BubbleMenuPluginOptions) => {
  return new Plugin({
    key: new PluginKey('menu_bubble'),
    view(editorView) {
      return new Menu({ editorView, options })
    },
  })
}

export { BubbleMenuPlugin }