import { Image, mergeAttributes, type Editor } from '@tiptap/core'
import type { Node as PMNode } from '@tiptap/pm/model'

/** NodeView 按钮点击回调注入接口。 */
export interface UploadNodeViewCallbacks {
  onRetry: (uploadId: string) => void
  onRemove: (uploadId: string) => void
}

/**
 * 上传图片占位符 NodeView：plain class，实现 ProseMirror NodeView 接口。
 *
 * 根据 data-upload-state 渲染三种态：
 * - null：普通 img
 * - uploading：img（本地 blob 预览）+ 遮罩（spinner + "上传中…"）
 * - error：img（灰化）+ 遮罩（⚠ + 错误文案 + 重试/移除按钮）
 *
 * NodeView 纯渲染，不发起上传——按钮点击转发给注入的 callbacks（实际是 coordinator）。
 * 属性变化时 ProseMirror 调 update(node)，NodeView 比较新旧 data-upload-state 重渲染遮罩。
 */
class UploadImageNodeView {
  private editor: Editor
  private node: PMNode
  private callbacks: UploadNodeViewCallbacks

  private container: HTMLDivElement
  private img: HTMLImageElement
  private overlay: HTMLDivElement | null = null

  constructor(opts: {
    node: PMNode
    editor: Editor
    HTMLAttributes: Record<string, unknown>
    callbacks: UploadNodeViewCallbacks
  }) {
    this.node = opts.node
    this.editor = opts.editor
    this.callbacks = opts.callbacks

    this.container = document.createElement('div')
    this.container.classList.add('upload-image-container')

    this.img = document.createElement('img')
    this.img.draggable = false
    const merged = mergeAttributes(opts.HTMLAttributes)
    Object.entries(merged).forEach(([k, v]) => {
      if (v != null) this.img.setAttribute(k, String(v))
    })
    const src = this.node.attrs.src
    if (src != null) this.img.src = src
    this.container.appendChild(this.img)

    this.renderOverlay()
  }

  get dom(): HTMLElement {
    return this.container
  }

  get contentDOM(): HTMLElement | null {
    return null
  }

  /** ProseMirror 调用：节点属性变化时重渲染遮罩。返回 false 拒绝非同类节点。 */
  update(node: PMNode): boolean {
    if (node.type !== this.node.type) return false
    const oldState = this.node.attrs['data-upload-state']
    const newState = node.attrs['data-upload-state']
    const oldSrc = this.node.attrs.src
    const newSrc = node.attrs.src
    this.node = node
    if (oldSrc !== newSrc && newSrc != null) {
      this.img.src = newSrc
    }
    if (oldState !== newState || this.overlay === null) {
      this.renderOverlay()
    }
    return true
  }

  /** 遮罩内按钮点击不被 ProseMirror 当编辑，避免误触发事务。 */
  ignoreMutation(): boolean {
    return true
  }

  /** 事件不被编辑器 stopEvent 拦截（按钮点击要响应）。 */
  stopEvent(_event: Event): boolean {
    return false
  }

  /** 根据 data-upload-state 渲染遮罩。null 时移除遮罩。 */
  private renderOverlay(): void {
    if (this.overlay) {
      this.overlay.remove()
      this.overlay = null
    }
    const state = this.node.attrs['data-upload-state']
    if (state == null) {
      this.container.classList.remove('is-uploading', 'is-error')
      return
    }
    this.overlay = document.createElement('div')
    this.overlay.classList.add('upload-image-overlay')
    if (state === 'uploading') {
      this.container.classList.add('is-uploading')
      this.container.classList.remove('is-error')
      this.overlay.innerHTML =
        '<div class="upload-spinner"></div><div class="upload-overlay-text">上传中…</div>'
    } else if (state === 'error') {
      this.container.classList.add('is-error')
      this.container.classList.remove('is-uploading')
      const msg = this.node.attrs['data-error-msg'] || '上传失败'
      this.overlay.innerHTML =
        '<div class="upload-error-icon">⚠</div>' +
        '<div class="upload-error-msg"></div>' +
        '<div class="upload-error-actions">' +
        '<button type="button" class="upload-btn upload-btn-retry">重试</button>' +
        '<button type="button" class="upload-btn upload-btn-remove">移除</button>' +
        '</div>'
      const msgEl = this.overlay.querySelector('.upload-error-msg') as HTMLElement
      msgEl.textContent = msg
      const uploadId = this.node.attrs['data-upload-id'] as string | null
      this.overlay.querySelector('.upload-btn-retry')?.addEventListener('click', (e) => {
        e.preventDefault()
        if (uploadId) this.callbacks.onRetry(uploadId)
      })
      this.overlay.querySelector('.upload-btn-remove')?.addEventListener('click', (e) => {
        e.preventDefault()
        if (uploadId) this.callbacks.onRemove(uploadId)
      })
    }
    this.container.appendChild(this.overlay)
  }

  destroy(): void {
    this.overlay?.remove()
    this.overlay = null
    this.container.remove()
  }
}

/** coordinator 引用（由 index.ts 在创建 editor 前注入）。 */
let coordinatorRef: { retryUpload: (id: string) => void; removeUpload: (id: string) => boolean } | null = null

/** index.ts 注入 coordinator，供 NodeView 的 onRetry/onRemove 调用。 */
export function setUploadCoordinator(c: typeof coordinatorRef): void {
  coordinatorRef = c
}

/**
 * 自定义 Image 扩展：继承父类属性，加三个上传状态属性，用自定义 NodeView。
 */
export const UploadImage = Image.configure({ allowBase64: true }).extend({
  addAttributes() {
    return {
      ...this.parent?.(),
      'data-upload-state': {
        default: null,
        parseHTML: (el) => (el as HTMLElement).getAttribute('data-upload-state'),
        renderHTML: (attrs) => {
          const v = attrs['data-upload-state']
          return v == null ? {} : { 'data-upload-state': v }
        },
      },
      'data-upload-id': {
        default: null,
        parseHTML: (el) => (el as HTMLElement).getAttribute('data-upload-id'),
        renderHTML: (attrs) => {
          const v = attrs['data-upload-id']
          return v == null ? {} : { 'data-upload-id': v }
        },
      },
      'data-error-msg': {
        default: null,
        parseHTML: (el) => (el as HTMLElement).getAttribute('data-error-msg'),
        renderHTML: (attrs) => {
          const v = attrs['data-error-msg']
          return v == null ? {} : { 'data-error-msg': v }
        },
      },
    }
  },

  addNodeView() {
    return ({ node, HTMLAttributes, editor }) => {
      return new UploadImageNodeView({
        node,
        editor,
        HTMLAttributes,
        callbacks: {
          onRetry: (id) => coordinatorRef?.retryUpload(id),
          onRemove: (id) => coordinatorRef?.removeUpload(id),
        },
      })
    }
  },
})