/**
 * Storage module implementation.
 * Persists FeedItems to database using Kysely.
 */

import type { Kysely } from 'kysely';
import type { FeedItem } from '../../interfaces/feed.types.js';
import type { IStorage } from '../../interfaces/storage.interface.js';
import type { Database, FeedItemTable } from '../../infrastructure/db/database.js';

export class SqlStorage implements IStorage {
  private readonly db: Kysely<Database>;

  constructor(db: Kysely<Database>) {
    this.db = db;
  }

  async save(items: FeedItem[]): Promise<void> {
    if (items.length === 0) {
      return;
    }

    const rows: FeedItemTable[] = items.map((item) => ({
      id: item.id,
      source: item.source,
      title: item.title,
      url: item.url,
      published_at: item.publishedAt.toISOString(),
      content: item.content ?? null,
      summary: item.summary ?? null,
      created_at: new Date().toISOString(),
    }));

    // Upsert: insert or update on conflict
    await this.db
      .insertInto('feed_items')
      .values(rows)
      .onConflict((oc) =>
        oc.column('id').doUpdateSet({
          title: (eb) => eb.ref('excluded.title'),
          content: (eb) => eb.ref('excluded.content'),
          summary: (eb) => eb.ref('excluded.summary'),
        })
      )
      .execute();
  }

  async getRecent(limit: number): Promise<FeedItem[]> {
    const rows = await this.db
      .selectFrom('feed_items')
      .selectAll()
      .orderBy('published_at', 'desc')
      .limit(limit)
      .execute();

    return rows.map(this.rowToFeedItem);
  }

  async getBySource(source: string, limit: number): Promise<FeedItem[]> {
    const rows = await this.db
      .selectFrom('feed_items')
      .selectAll()
      .where('source', '=', source)
      .orderBy('published_at', 'desc')
      .limit(limit)
      .execute();

    return rows.map(this.rowToFeedItem);
  }

  async search(query: string): Promise<FeedItem[]> {
    const searchTerm = `%${query}%`;

    const rows = await this.db
      .selectFrom('feed_items')
      .selectAll()
      .where((eb) =>
        eb.or([
          eb('title', 'like', searchTerm),
          eb('summary', 'like', searchTerm),
          eb('content', 'like', searchTerm),
        ])
      )
      .orderBy('published_at', 'desc')
      .execute();

    return rows.map(this.rowToFeedItem);
  }

  private rowToFeedItem(row: FeedItemTable): FeedItem {
    return {
      id: row.id,
      source: row.source,
      title: row.title,
      url: row.url,
      publishedAt: new Date(row.published_at),
      content: row.content ?? undefined,
      summary: row.summary ?? undefined,
    };
  }
}