<?php

namespace App\Http\Controllers\Api\V1;

use Domains\Settings\Models\Language;
use Domains\Settings\Services\LanguageService;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;

class LanguagesController extends BaseController
{
    public function __construct(
        private LanguageService $languageService
    ) {}

    /**
     * Get languages available for route creation
     * Returns languages that have both active feeds and active channels
     */
    public function availableForRoutes(): JsonResponse
    {
        $languages = $this->languageService->getAvailableForRoutes();

        return $this->sendResponse(
            $languages,
            'Available languages for routes retrieved successfully.'
        );
    }

    /**
     * Get feeds filtered by language
     */
    public function feedsByLanguage(Request $request, int $languageId): JsonResponse
    {
        $fields = $this->parseFields($request->get('fields'), [
            'feeds.id', 'feeds.name', 'feeds.url', 'feeds.type', 'feeds.provider'
        ]);
        
        $feeds = $this->languageService->getFeedsByLanguage(
            $languageId,
            $request->get('search'),
            (int) $request->get('per_page', 15),
            $fields
        );

        $language = Language::select(['name'])->findOrFail($languageId);

        return $this->sendResponse(
            $feeds,
            "Feeds for language '{$language->name}' retrieved successfully."
        );
    }

    /**
     * Get channels filtered by language
     */
    public function channelsByLanguage(Request $request, int $languageId): JsonResponse
    {
        $fields = $this->parseFields($request->get('fields'), [
            'id', 'platform_instance_id', 'name', 'display_name', 'description', 'language_id'
        ]);
        
        $channels = $this->languageService->getChannelsByLanguage(
            $languageId,
            $request->get('search'),
            (int) $request->get('per_page', 15),
            $fields
        );

        $language = Language::select(['name'])->findOrFail($languageId);

        return $this->sendResponse(
            $channels,
            "Channels for language '{$language->name}' retrieved successfully."
        );
    }

    /**
     * Get language statistics
     */
    public function statistics(int $languageId): JsonResponse
    {
        $stats = $this->languageService->getLanguageStatistics($languageId);
        $language = Language::select(['name'])->findOrFail($languageId);

        return $this->sendResponse(
            $stats,
            "Statistics for language '{$language->name}' retrieved successfully."
        );
    }

    /**
     * Get usage summary for all languages
     */
    public function usageSummary(): JsonResponse
    {
        $summary = $this->languageService->getLanguageUsageSummary();

        return $this->sendResponse(
            $summary,
            'Language usage summary retrieved successfully.'
        );
    }

    /**
     * Get common languages between feed and channel
     */
    public function commonLanguages(Request $request): JsonResponse
    {
        $request->validate([
            'feed_id' => 'required|exists:feeds,id',
            'channel_id' => 'required|exists:platform_channels,id'
        ]);

        $commonLanguages = $this->languageService->getCommonLanguages(
            $request->get('feed_id'),
            $request->get('channel_id')
        );

        return $this->sendResponse(
            $commonLanguages,
            'Common languages retrieved successfully.'
        );
    }

    /**
     * Parse field selection from request
     */
    private function parseFields(?string $fieldsParam, array $defaultFields): array
    {
        if (!$fieldsParam) {
            return $defaultFields;
        }

        $requestedFields = array_map('trim', explode(',', $fieldsParam));
        $validFields = [];

        foreach ($requestedFields as $field) {
            if (in_array($field, $defaultFields) || str_contains($field, '.')) {
                $validFields[] = $field;
            }
        }

        return empty($validFields) ? $defaultFields : $validFields;
    }
}