/**
 * Component: Author Search API Route
 * Documentation: documentation/integrations/audible.md
 */

import { NextRequest, NextResponse } from 'next/server';
import { getCurrentUser } from '@/lib/middleware/auth';
import { getConfigService } from '@/lib/services/config.service';
import { AUDIBLE_REGIONS, DEFAULT_AUDIBLE_REGION, AudibleRegion } from '@/lib/types/audible';
import { RMABLogger } from '@/lib/utils/logger';
import {
  AudnexusAuthorDetail,
  searchAuthors,
  fetchAuthorDetail,
} from '@/lib/integrations/audnexus-authors';

const logger = RMABLogger.create('API.Authors.Search');

/**
 * GET /api/authors/search?name=Brandon Sanderson
 * Search for authors on Audnexus, deduplicate, and return enriched details
 */
export async function GET(request: NextRequest) {
  try {
    // Require authentication
    const currentUser = getCurrentUser(request);
    if (!currentUser) {
      return NextResponse.json(
        { error: 'Unauthorized', message: 'Authentication required' },
        { status: 401 }
      );
    }

    const name = request.nextUrl.searchParams.get('name');

    if (!name || name.trim().length === 0) {
      return NextResponse.json(
        { error: 'ValidationError', message: 'Author name is required' },
        { status: 400 }
      );
    }

    // Get configured Audible region
    const configService = getConfigService();
    const audibleRegion: AudibleRegion = await configService.getAudibleRegion();
    const region = AUDIBLE_REGIONS[audibleRegion]?.audnexusParam || AUDIBLE_REGIONS[DEFAULT_AUDIBLE_REGION].audnexusParam;

    logger.info(`Searching authors: "${name}" (region: ${region})`);

    // Step 1: Search for authors (returns list with potential duplicates)
    const searchResults = await searchAuthors(name.trim(), region);

    if (searchResults.length === 0) {
      return NextResponse.json({
        success: true,
        authors: [],
        query: name.trim(),
      });
    }

    // Step 2: Fetch details for all unique authors in parallel
    const detailPromises = searchResults.map(author => fetchAuthorDetail(author.asin, region));
    const detailResults = await Promise.all(detailPromises);

    // Step 3: Build enriched results, filtering out any failed fetches
    const authors = detailResults
      .filter((detail): detail is AudnexusAuthorDetail => detail !== null)
      .map(detail => ({
        asin: detail.asin,
        name: detail.name,
        description: detail.description || undefined,
        image: detail.image || undefined,
        genres: detail.genres?.map(g => g.name).slice(0, 3) || [],
        similarCount: detail.similar?.length || 0,
      }));

    logger.info(`Author search complete: "${name}" → ${authors.length} results`);

    return NextResponse.json({
      success: true,
      authors,
      query: name.trim(),
    });
  } catch (error) {
    logger.error('Failed to search authors', { error: error instanceof Error ? error.message : String(error) });
    return NextResponse.json(
      { error: 'SearchError', message: 'Failed to search authors' },
      { status: 500 }
    );
  }
}