import type { AtpAgent } from "@atproto/api";
import type { Database } from "@atbb/db";
import { boards } from "@atbb/db";
import { eq, and } from "drizzle-orm";
import { deriveSlug } from "../slug.js";

interface CreateBoardInput {
  name: string;
  description?: string;
  slug?: string;
  sortOrder?: number;
  categoryUri: string;  // AT URI: at://did/space.atbb.forum.category/rkey
  categoryId: bigint;   // DB FK
  categoryCid: string;  // CID for the category strongRef
}

interface CreateBoardResult {
  created: boolean;
  skipped: boolean;
  uri?: string;
  cid?: string;
  existingName?: string;
}

/**
 * Create a space.atbb.forum.board record on the Forum DID's PDS
 * and insert it into the database.
 * Idempotent: skips if a board with the same name in the same category exists.
 */
export async function createBoard(
  db: Database,
  agent: AtpAgent,
  forumDid: string,
  input: CreateBoardInput
): Promise<CreateBoardResult> {
  // Check if board with this name already exists in the category
  const [existing] = await db
    .select()
    .from(boards)
    .where(
      and(
        eq(boards.did, forumDid),
        eq(boards.name, input.name),
        eq(boards.categoryUri, input.categoryUri)
      )
    )
    .limit(1);

  if (existing) {
    return {
      created: false,
      skipped: true,
      uri: `at://${existing.did}/space.atbb.forum.board/${existing.rkey}`,
      cid: existing.cid,
      existingName: existing.name,
    };
  }

  const slug = input.slug ?? deriveSlug(input.name);
  const now = new Date();

  const response = await agent.com.atproto.repo.createRecord({
    repo: forumDid,
    collection: "space.atbb.forum.board",
    record: {
      $type: "space.atbb.forum.board",
      name: input.name,
      ...(input.description && { description: input.description }),
      slug,
      ...(input.sortOrder !== undefined && { sortOrder: input.sortOrder }),
      // categoryRef shape: { category: strongRef }
      category: {
        category: {
          uri: input.categoryUri,
          cid: input.categoryCid,
        },
      },
      createdAt: now.toISOString(),
    },
  });

  const rkey = response.data.uri.split("/").pop()!;

  await db.insert(boards).values({
    did: forumDid,
    rkey,
    cid: response.data.cid,
    name: input.name,
    description: input.description ?? null,
    slug,
    sortOrder: input.sortOrder ?? null,
    categoryId: input.categoryId,
    categoryUri: input.categoryUri,
    createdAt: now,
    indexedAt: now,
  });

  return {
    created: true,
    skipped: false,
    uri: response.data.uri,
    cid: response.data.cid,
  };
}