import type { Kysely, Transaction } from 'kysely';

import type { IdentityDatabaseSchema } from '../types/database';
import type { FactRecord, TopicRecord } from '../types/domain';

export type DatabaseExecutor = Kysely<IdentityDatabaseSchema> | Transaction<IdentityDatabaseSchema>;

export interface FactTopicJoinRow extends TopicRecord {
  fact_id: string;
  role: string | null;
  position: number;
}

export async function findFactRowsForTopicId(
  executor: DatabaseExecutor,
  topicId: string,
): Promise<FactRecord[]> {
  return executor
    .selectFrom('facts')
    .innerJoin('fact_topics', 'fact_topics.fact_id', 'facts.id')
    .selectAll('facts')
    .where('fact_topics.topic_id', '=', topicId)
    .orderBy('facts.created_at', 'asc')
    .execute();
}

export async function findFactRowsConnectingTopicIds(
  executor: DatabaseExecutor,
  topicIds: string[],
): Promise<FactRecord[]> {
  if (topicIds.length === 0) {
    return [];
  }

  return executor
    .selectFrom('facts')
    .innerJoin('fact_topics', 'fact_topics.fact_id', 'facts.id')
    .selectAll('facts')
    .where('fact_topics.topic_id', 'in', topicIds)
    .groupBy('facts.id')
    .having((eb) => eb.fn.count<number>('fact_topics.topic_id'), '=', topicIds.length)
    .orderBy('facts.created_at', 'asc')
    .execute();
}

export async function findTopicLinksForFactIds(
  executor: DatabaseExecutor,
  factIds: string[],
): Promise<FactTopicJoinRow[]> {
  if (factIds.length === 0) {
    return [];
  }

  return executor
    .selectFrom('fact_topics')
    .innerJoin('topics', 'topics.id', 'fact_topics.topic_id')
    .selectAll('topics')
    .select([
      'fact_topics.fact_id as fact_id',
      'fact_topics.role as role',
      'fact_topics.position as position',
    ])
    .where('fact_topics.fact_id', 'in', factIds)
    .orderBy('fact_topics.position', 'asc')
    .execute() as Promise<FactTopicJoinRow[]>;
}