import type { CollectionConfig } from 'payload'

/* One like per user per post. `likes`/`views` counters live on the post doc;
   this collection records who liked what so the toggle is idempotent. */
const PostLikes: CollectionConfig = {
  slug: 'post-likes',
  admin: {
    useAsTitle: 'id',
    defaultColumns: ['user', 'post', 'createdAt'],
  },
  access: {
    read: () => true,
    create: ({ req }) => !!req.user,
    delete: ({ req }) => {
      // Admins and the like owner can unlike
      const user = req.user as { id?: number | string; role?: string } | undefined
      if (user?.role === 'admin') return true
      return { user: { equals: user?.id } }
    },
  },
  fields: [
    { name: 'user', type: 'relationship', relationTo: 'users', required: true, index: true },
    { name: 'post', type: 'relationship', relationTo: 'posts', required: true, index: true },
  ],
  hooks: {
    beforeValidate: [
      async ({ data, req, operation }) => {
        if (operation !== 'create' || !data || !req.payload) return data
        const existing = await req.payload.find({
          collection: 'post-likes',
          where: {
            and: [
              { user: { equals: data.user } },
              { post: { equals: data.post } },
            ],
          },
          limit: 1,
        })
        if (existing.docs.length > 0) throw new Error('already-liked')
        return data
      },
    ],
  },
}

export default PostLikes