import { allow, deny } from "@/lib/decision"
import { toApiError } from "@/lib/errors"
import type { Comment } from "@/lib/types"

import { httpJson } from "./http"

type Paginated<T> = {
  items: T[]
  meta: {
    total: number
    offset: number
    limit: number
  }
}

type ListOptions = {
  offset?: number
  limit?: number
}

function withOffsetLimit(path: string, options?: ListOptions): string {
  const offset = options?.offset ?? 0
  const limit = options?.limit ?? 100
  const searchParams = new URLSearchParams({
    offset: String(offset),
    limit: String(limit),
  })
  return `${path}?${searchParams.toString()}`
}

export async function listCommentsByPost(
  postId: string,
  options?: ListOptions,
): Promise<Comment[]> {
  const encodedId = encodeURIComponent(postId)
  const res = await httpJson<Paginated<Comment>>(
    withOffsetLimit(`/api/v1/posts/${encodedId}/comments`, options),
    {
      cache: "no-store",
    },
  )
  return res.items
}

export async function addComment(postId: string, content: string) {
  const encodedId = encodeURIComponent(postId)
  try {
    await httpJson<unknown>(`/api/v1/posts/${encodedId}/comments`, {
      method: "POST",
      cache: "no-store",
      json: { content },
    })
    return allow()
  } catch (err: unknown) {
    if (err instanceof Error && err.message === "UNAUTHORIZED") {
      return deny(401, "请先登录")
    }
    const apiError = toApiError(err)
    return deny(apiError.code, apiError.msg)
  }
}

export async function toggleCommentLike(commentId: string, currentlyLiked: boolean) {
  const encodedId = encodeURIComponent(commentId)
  try {
    if (currentlyLiked) {
      await httpJson<unknown>(`/api/v1/comments/${encodedId}/like`, {
        method: "DELETE",
        cache: "no-store",
      })
    } else {
      await httpJson<unknown>(`/api/v1/comments/${encodedId}/like`, {
        method: "POST",
        cache: "no-store",
      })
    }
    return allow()
  } catch (err: unknown) {
    if (err instanceof Error && err.message === "UNAUTHORIZED") {
      return deny(401, "请先登录")
    }
    const apiError = toApiError(err)
    return deny(apiError.code, apiError.msg)
  }
}