import type {
  ContextMenuParams,
  MenuItemConstructorOptions,
  WebContents,
} from 'electron/main'
import { clipboard, shell } from 'electron'
import { Menu } from 'electron/main'

type WebContextMenuOptions = {
  allowNavigation?: boolean
}

function isRemoteURL(url: string | undefined): boolean {
  return /^https?:\/\//i.test(url ?? '')
}

function hasVisibleText(value: string | undefined): boolean {
  return Boolean(value?.trim())
}

function pushSeparator(items: MenuItemConstructorOptions[]): void {
  if (items.length > 0 && items.at(-1)?.type !== 'separator') {
    items.push({ type: 'separator' })
  }
}

function trimTrailingSeparators(items: MenuItemConstructorOptions[]): MenuItemConstructorOptions[] {
  while (items.at(-1)?.type === 'separator') {
    items.pop()
  }
  return items
}

function writeClipboardText(text: string): void {
  if (text) {
    clipboard.writeText(text)
  }
}

function buildContextMenuTemplate(
  webContents: WebContents,
  params: ContextMenuParams,
  options: Required<WebContextMenuOptions>,
): MenuItemConstructorOptions[] {
  const items: MenuItemConstructorOptions[] = []
  const editFlags = params.editFlags
  const canCopy = editFlags.canCopy || hasVisibleText(params.selectionText)
  const canSelectAll = editFlags.canSelectAll || params.isEditable

  if (params.isEditable) {
    items.push(
      {
        label: '撤销',
        enabled: editFlags.canUndo,
        click: () => webContents.undo(),
      },
      {
        label: '重做',
        enabled: editFlags.canRedo,
        click: () => webContents.redo(),
      },
      { type: 'separator' },
      {
        label: '剪切',
        enabled: editFlags.canCut,
        click: () => webContents.cut(),
      },
      {
        label: '复制',
        enabled: canCopy,
        click: () => webContents.copy(),
      },
      {
        label: '粘贴',
        enabled: editFlags.canPaste,
        click: () => webContents.paste(),
      },
      {
        label: '删除',
        enabled: editFlags.canDelete,
        click: () => webContents.delete(),
      },
      { type: 'separator' },
      {
        label: '全选',
        enabled: canSelectAll,
        click: () => webContents.selectAll(),
      },
    )
  } else if (canCopy) {
    items.push({
      label: '复制',
      click: () => webContents.copy(),
    })
  }

  if (hasVisibleText(params.selectionText)) {
    pushSeparator(items)
    items.push({
      label: '复制所选文字',
      click: () => writeClipboardText(params.selectionText),
    })
  }

  if (isRemoteURL(params.linkURL)) {
    pushSeparator(items)
    items.push(
      {
        label: '复制链接',
        click: () => writeClipboardText(params.linkURL),
      },
      {
        label: '在浏览器中打开链接',
        click: () => {
          void shell.openExternal(params.linkURL)
        },
      },
    )
  }

  if (params.mediaType === 'image' && params.hasImageContents) {
    pushSeparator(items)
    items.push({
      label: '复制图片',
      click: () => webContents.copyImageAt(params.x, params.y),
    })
    if (isRemoteURL(params.srcURL)) {
      items.push({
        label: '复制图片地址',
        click: () => writeClipboardText(params.srcURL),
      })
    }
  } else if (isRemoteURL(params.srcURL)) {
    pushSeparator(items)
    items.push({
      label: '复制媒体地址',
      click: () => writeClipboardText(params.srcURL),
    })
  }

  if (options.allowNavigation) {
    pushSeparator(items)
    items.push(
      {
        label: '后退',
        enabled: webContents.navigationHistory.canGoBack(),
        click: () => webContents.navigationHistory.goBack(),
      },
      {
        label: '前进',
        enabled: webContents.navigationHistory.canGoForward(),
        click: () => webContents.navigationHistory.goForward(),
      },
      {
        label: '重新加载',
        enabled: !webContents.isDestroyed(),
        click: () => webContents.reload(),
      },
    )
  }

  return trimTrailingSeparators(items)
}

export function attachWebContextMenu(
  webContents: WebContents,
  options: WebContextMenuOptions = {},
): void {
  const resolvedOptions: Required<WebContextMenuOptions> = {
    allowNavigation: options.allowNavigation ?? true,
  }

  webContents.on('context-menu', (event, params) => {
    const template = buildContextMenuTemplate(webContents, params, resolvedOptions)
    if (template.length === 0) {
      return
    }

    event.preventDefault()
    Menu.buildFromTemplate(template).popup({
      frame: params.frame ?? undefined,
      sourceType: params.menuSourceType,
    })
  })
}