import type { AvatarSize } from '@langgenius/dify-ui/avatar'
import type { FC } from 'react'
import { AvatarFallback, AvatarImage, AvatarRoot } from '@langgenius/dify-ui/avatar'
import { memo } from 'react'
import { getUserColor } from '@/app/components/workflow/collaboration/utils/user-color'
import { useAppContext } from '@/context/app-context'

type User = {
  id: string
  name: string
  avatar_url?: string | null
}

type UserAvatarListProps = {
  users: User[]
  maxVisible?: number
  size?: AvatarSize
  className?: string
  showCount?: boolean
}

const avatarSizeToPx: Record<AvatarSize, number> = {
  'xxs': 16,
  'xs': 20,
  'sm': 24,
  'md': 32,
  'lg': 36,
  'xl': 40,
  '2xl': 48,
  '3xl': 64,
}

export const UserAvatarList: FC<UserAvatarListProps> = memo(({
  users,
  maxVisible = 3,
  size = 'sm',
  className = '',
  showCount = true,
}) => {
  const { userProfile } = useAppContext()
  if (!users.length)
    return null

  const shouldShowCount = showCount && users.length > maxVisible
  const actualMaxVisible = shouldShowCount ? Math.max(1, maxVisible - 1) : maxVisible
  const visibleUsers = users.slice(0, actualMaxVisible)
  const remainingCount = users.length - actualMaxVisible

  const currentUserId = userProfile?.id

  return (
    <div className={`flex items-center -space-x-1 ${className}`}>
      {visibleUsers.map((user, index) => {
        const isCurrentUser = user.id === currentUserId
        const userColor = isCurrentUser ? undefined : getUserColor(user.id)
        return (
          <div
            key={`${user.id}-${index}`}
            className="relative"
            style={{ zIndex: visibleUsers.length - index }}
          >
            <AvatarRoot size={size} className="ring-2 ring-components-panel-bg">
              {user.avatar_url && (
                <AvatarImage
                  src={user.avatar_url}
                  alt={user.name}
                />
              )}
              <AvatarFallback
                size={size}
                style={userColor ? { backgroundColor: userColor } : undefined}
              >
                {user.name?.[0]?.toLocaleUpperCase()}
              </AvatarFallback>
            </AvatarRoot>
          </div>
        )
      },

      )}
      {shouldShowCount && remainingCount > 0 && (
        <div className="relative shrink-0" style={{ zIndex: 0 }}>
          <div
            className="inline-flex items-center justify-center rounded-full bg-gray-500 text-[10px] leading-none text-white ring-2 ring-components-panel-bg"
            style={{
              width: avatarSizeToPx[size],
              height: avatarSizeToPx[size],
            }}
          >
            +
            {remainingCount}
          </div>
        </div>
      )}
    </div>
  )
})

UserAvatarList.displayName = 'UserAvatarList'