<?php

namespace App\Http\Controllers;

use Blacklight\ManticoreSearch;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\RateLimiter;

class SearchSuggestController extends Controller
{
    private ManticoreSearch $manticore;

    public function __construct()
    {
        $this->manticore = new ManticoreSearch;
    }

    /**
     * Get autocomplete suggestions for search input.
     */
    public function autocomplete(Request $request): JsonResponse
    {
        $query = $request->input('q', '');
        // Use the index from ManticoreSearch config, or allow override via request
        $index = $request->input('index') ?? $this->manticore->getReleasesIndex();

        // Rate limiting: 60 requests per minute per IP
        $key = 'autocomplete:'.$request->ip();
        if (RateLimiter::tooManyAttempts($key, 60)) {
            return response()->json([
                'success' => false,
                'error' => 'Too many requests',
            ], 429);
        }
        RateLimiter::hit($key, 60);

        if (! $this->manticore->isAutocompleteEnabled()) {
            return response()->json([
                'success' => true,
                'suggestions' => [],
            ]);
        }

        if (strlen($query) < 2) {
            return response()->json([
                'success' => true,
                'suggestions' => [],
            ]);
        }

        try {
            $suggestions = $this->manticore->autocomplete($query, $index);

            return response()->json([
                'success' => true,
                'query' => $query,
                'suggestions' => array_map(fn ($s) => $s['suggest'], $suggestions),
            ]);
        } catch (\Throwable $e) {
            return response()->json([
                'success' => true,
                'query' => $query,
                'suggestions' => [],
            ]);
        }
    }

    /**
     * Get spell correction suggestions ("Did you mean?").
     */
    public function suggest(Request $request): JsonResponse
    {
        $query = $request->input('q', '');
        $index = $request->input('index', 'releases_rt');

        // Rate limiting: 30 requests per minute per IP
        $key = 'suggest:'.$request->ip();
        if (RateLimiter::tooManyAttempts($key, 30)) {
            return response()->json([
                'success' => false,
                'error' => 'Too many requests',
            ], 429);
        }
        RateLimiter::hit($key, 60);

        if (! $this->manticore->isSuggestEnabled()) {
            return response()->json([
                'success' => false,
                'suggestions' => [],
                'error' => 'Suggest is disabled',
            ]);
        }

        if (empty($query)) {
            return response()->json([
                'success' => true,
                'suggestions' => [],
            ]);
        }

        $suggestions = $this->manticore->suggest($query, $index);

        // Get the best suggestion (highest doc count)
        $bestSuggestion = null;
        if (! empty($suggestions)) {
            usort($suggestions, fn ($a, $b) => $b['docs'] - $a['docs']);
            $bestSuggestion = $suggestions[0]['suggest'] ?? null;
        }

        return response()->json([
            'success' => true,
            'query' => $query,
            'suggestions' => array_map(fn ($s) => $s['suggest'], $suggestions),
            'best' => $bestSuggestion,
            'details' => $suggestions,
        ]);
    }

    /**
     * Combined endpoint for search assistance (autocomplete + suggest).
     */
    public function searchAssist(Request $request): JsonResponse
    {
        $query = $request->input('q', '');
        $index = $request->input('index', 'releases_rt');

        // Rate limiting
        $key = 'searchassist:'.$request->ip();
        if (RateLimiter::tooManyAttempts($key, 60)) {
            return response()->json([
                'success' => false,
                'error' => 'Too many requests',
            ], 429);
        }
        RateLimiter::hit($key, 60);

        $response = [
            'success' => true,
            'query' => $query,
            'autocomplete' => [],
            'suggest' => null,
        ];

        // Get autocomplete suggestions
        if ($this->manticore->isAutocompleteEnabled() && strlen($query) >= 2) {
            $autocomplete = $this->manticore->autocomplete($query, $index);
            $response['autocomplete'] = array_map(fn ($s) => $s['suggest'], $autocomplete);
        }

        // Get spell suggestion if query is complete (user stopped typing)
        if ($this->manticore->isSuggestEnabled() && ! empty($query)) {
            $suggestions = $this->manticore->suggest($query, $index);
            if (! empty($suggestions)) {
                usort($suggestions, fn ($a, $b) => $b['docs'] - $a['docs']);
                $response['suggest'] = $suggestions[0]['suggest'] ?? null;
            }
        }

        return response()->json($response);
    }
}