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

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 currentUserId = useAtomValue(userProfileIdAtom)
    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

    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'