<?php

declare(strict_types=1);

namespace Yatra\Services;

use Yatra\Repositories\ReviewRepository;
use Yatra\Repositories\TripRepository;

/**
 * Review Service
 * 
 * Contains business logic for trip reviews.
 * 
 * @package Yatra\Services
 */
class ReviewService
{
    private ReviewRepository $reviewRepository;
    private TripRepository $tripRepository;

    public function __construct()
    {
        $this->reviewRepository = new ReviewRepository();
        $this->tripRepository = new TripRepository();
    }

    /**
     * Get paginated reviews
     * 
     * @param array $filters Filters
     * @return array
     */
    public function getReviews(array $filters = []): array
    {
        $result = $this->reviewRepository->paginate($filters);

        $result['data'] = array_map([$this, 'formatReview'], $result['data']);

        return $result;
    }

    /**
     * Get single review
     * 
     * @param int $id Review ID
     * @return array|null
     */
    public function getReview(int $id): ?array
    {
        $review = $this->reviewRepository->findWithTrip($id);

        if (!$review) {
            return null;
        }

        return $this->formatReview($review);
    }

    /**
     * Get approved reviews for a trip
     * 
     * @param int $tripId Trip ID
     * @param int $limit  Limit results
     * @return array
     */
    public function getTripReviews(int $tripId, int $limit = 10): array
    {
        $reviews = $this->reviewRepository->findApprovedByTripId($tripId, $limit);

        return array_map([$this, 'formatReview'], $reviews);
    }

    /**
     * Get trip rating summary
     * 
     * @param int $tripId Trip ID
     * @return array
     */
    public function getTripRatingSummary(int $tripId): array
    {
        return [
            'average_rating' => $this->reviewRepository->getAverageRating($tripId),
            'review_count' => $this->reviewRepository->getReviewCount($tripId),
            'distribution' => $this->reviewRepository->getRatingDistribution($tripId),
        ];
    }

    /**
     * Submit a review
     * 
     * @param array $data Review data
     * @return array {success: bool, review_id?: int, message: string}
     */
    public function submitReview(array $data): array
    {
        // Validate required fields
        if (empty($data['trip_id']) || empty($data['rating'])) {
            return ['success' => false, 'message' => __('Trip and rating are required.', 'yatra')];
        }

        // Validate trip exists
        $trip = $this->tripRepository->find((int) $data['trip_id']);
        if (!$trip) {
            return ['success' => false, 'message' => __('Trip not found.', 'yatra')];
        }

        // Validate rating
        $rating = (int) $data['rating'];
        if ($rating < 1 || $rating > 5) {
            return ['success' => false, 'message' => __('Rating must be between 1 and 5.', 'yatra')];
        }

        // Check if user already reviewed this trip
        $userId = $data['user_id'] ?? get_current_user_id();
        if ($userId) {
            $existingReview = $this->reviewRepository->findByUserAndTrip($userId, (int) $data['trip_id']);
            if ($existingReview) {
                return ['success' => false, 'message' => __('You have already reviewed this trip.', 'yatra')];
            }
            $data['user_id'] = $userId;
        }

        // Set reviewer info from user if logged in
        if ($userId && empty($data['reviewer_name'])) {
            $user = get_userdata($userId);
            if ($user) {
                $data['reviewer_name'] = $user->display_name;
                $data['reviewer_email'] = $user->user_email;
            }
        }

        // Set default status
        $settings = SettingsService::getSettings();
        $autoApprove = $settings['reviews']['auto_approve'] ?? false;
        $data['status'] = $autoApprove ? 'approved' : 'pending';

        // Create review
        $reviewId = $this->reviewRepository->create($data);

        if (!$reviewId) {
            return ['success' => false, 'message' => __('Failed to submit review.', 'yatra')];
        }

        // Update trip rating cache
        $this->updateTripRatingCache((int) $data['trip_id']);

        return [
            'success' => true,
            'review_id' => $reviewId,
            'message' => $autoApprove 
                ? __('Thank you for your review!', 'yatra')
                : __('Thank you! Your review is pending approval.', 'yatra'),
        ];
    }

    /**
     * Create a review on behalf of a customer (admin path).
     *
     * Differs from {@see submitReview()} in three deliberate ways:
     *
     *   1. Skips the "already reviewed this trip" guard. An admin entering
     *      a customer's quote from email isn't a duplicate the user can fix.
     *   2. Skips the `reviews.auto_approve` setting lookup. The status
     *      arrives from the operator (already enum-clamped by the
     *      controller) and is the source of truth.
     *   3. Doesn't fall back to the current user's display_name/email as
     *      reviewer — admins enter the customer's identity by hand.
     *
     * Field aliasing (customer_name → author_name etc.) is handled at the
     * controller layer; this method receives canonical column names only.
     *
     * @param array $data Canonical review payload: trip_id, rating, title,
     *                    content, author_name, author_email, status,
     *                    optional created_by.
     * @return array {success: bool, review_id?: int, message: string}
     */
    public function createReviewAsAdmin(array $data): array
    {
        if (empty($data['trip_id']) || empty($data['rating'])) {
            return ['success' => false, 'message' => __('Trip and rating are required.', 'yatra')];
        }

        $trip = $this->tripRepository->find((int) $data['trip_id']);
        if (!$trip) {
            return ['success' => false, 'message' => __('Trip not found.', 'yatra')];
        }

        $rating = (int) $data['rating'];
        if ($rating < 1 || $rating > 5) {
            return ['success' => false, 'message' => __('Rating must be between 1 and 5.', 'yatra')];
        }

        if (empty($data['author_name'])) {
            return ['success' => false, 'message' => __('Customer name is required.', 'yatra')];
        }
        if (empty($data['content'])) {
            return ['success' => false, 'message' => __('Review content is required.', 'yatra')];
        }

        // Default status only when the controller didn't supply one. The
        // controller already clamps the value against the ENUM so we
        // trust it as-is when present.
        if (!isset($data['status']) || $data['status'] === '') {
            $data['status'] = 'pending';
        }

        try {
            $reviewId = $this->reviewRepository->create($data);
        } catch (\Throwable $e) {
            return [
                'success' => false,
                'message' => __('Failed to create review.', 'yatra') . ' ' . $e->getMessage(),
            ];
        }

        if (!$reviewId) {
            return ['success' => false, 'message' => __('Failed to create review.', 'yatra')];
        }

        $this->updateTripRatingCache((int) $data['trip_id']);

        return [
            'success'   => true,
            'review_id' => $reviewId,
            'message'   => __('Review created successfully.', 'yatra'),
        ];
    }

    /**
     * Update a review
     *
     * @param int   $id   Review ID
     * @param array $data Review data
     * @return array {success: bool, message: string}
     */
    public function updateReview(int $id, array $data): array
    {
        $review = $this->reviewRepository->find($id);

        if (!$review) {
            return ['success' => false, 'message' => __('Review not found.', 'yatra')];
        }

        // Check if user can edit
        $userId = get_current_user_id();
        if ($userId && !current_user_can('manage_options')) {
            if (!$this->reviewRepository->canUserEdit($id, $userId)) {
                return ['success' => false, 'message' => __('You cannot edit this review.', 'yatra')];
            }
        }

        // Validate rating if provided
        if (isset($data['rating'])) {
            $rating = (int) $data['rating'];
            if ($rating < 1 || $rating > 5) {
                return ['success' => false, 'message' => __('Rating must be between 1 and 5.', 'yatra')];
            }
        }

        $updated = $this->reviewRepository->update($id, $data);

        if (!$updated) {
            return ['success' => false, 'message' => __('Failed to update review.', 'yatra')];
        }

        // Update trip rating cache
        $this->updateTripRatingCache((int) $review->trip_id);

        return [
            'success' => true,
            'message' => __('Review updated successfully.', 'yatra'),
        ];
    }

    /**
     * Update review status
     * 
     * @param int    $id     Review ID
     * @param string $status New status
     * @return array {success: bool, message: string}
     */
    public function updateStatus(int $id, string $status): array
    {
        $validStatuses = ['pending', 'approved', 'rejected', 'spam', 'trash'];

        if (!in_array($status, $validStatuses, true)) {
            return ['success' => false, 'message' => __('Invalid status.', 'yatra')];
        }

        $review = $this->reviewRepository->find($id);

        if (!$review) {
            return ['success' => false, 'message' => __('Review not found.', 'yatra')];
        }

        $updated = $this->reviewRepository->updateStatus($id, $status);

        if (!$updated) {
            return ['success' => false, 'message' => __('Failed to update status.', 'yatra')];
        }

        // Update trip rating cache
        $this->updateTripRatingCache((int) $review->trip_id);

        return [
            'success' => true,
            'message' => sprintf(
                /* translators: %s: new review status. */
                __('Review status updated to %s.', 'yatra'),
                $status
            ),
        ];
    }

    /**
     * Bulk update review status
     *
     * @param array  $ids    Review IDs
     * @param string $status New status
     * @return array {success: bool, affected: int, message: string}
     */
    public function bulkUpdateStatus(array $ids, string $status): array
    {
        $validStatuses = ['pending', 'approved', 'rejected', 'spam', 'trash'];

        if (!in_array($status, $validStatuses, true)) {
            return ['success' => false, 'affected' => 0, 'message' => __('Invalid status.', 'yatra')];
        }

        $affected = $this->reviewRepository->bulkUpdateStatus($ids, $status);

        return [
            'success'  => true,
            'affected' => $affected,
            'message'  => sprintf(
                /* translators: %d: number of reviews updated. */
                __('%d reviews updated.', 'yatra'),
                $affected
            ),
        ];
    }

    /**
     * Bulk delete reviews
     *
     * @param array $ids Review IDs
     * @return array {success: bool, affected: int, message: string}
     */
    public function bulkDelete(array $ids): array
    {
        $affected = $this->reviewRepository->bulkDelete($ids);

        return [
            'success'  => true,
            'affected' => $affected,
            'message'  => sprintf(
                /* translators: %d: number of reviews deleted. */
                __('%d reviews deleted.', 'yatra'),
                $affected
            ),
        ];
    }

    /**
     * Delete a review
     * 
     * @param int $id Review ID
     * @return array {success: bool, message: string}
     */
    public function deleteReview(int $id): array
    {
        $review = $this->reviewRepository->find($id);

        if (!$review) {
            return ['success' => false, 'message' => __('Review not found.', 'yatra')];
        }

        $tripId = (int) $review->trip_id;

        $deleted = $this->reviewRepository->delete($id);

        if (!$deleted) {
            return ['success' => false, 'message' => __('Failed to delete review.', 'yatra')];
        }

        // Update trip rating cache
        $this->updateTripRatingCache($tripId);

        return [
            'success' => true,
            'message' => __('Review deleted successfully.', 'yatra'),
        ];
    }

    /**
     * Check if user can review a trip
     * 
     * @param int      $tripId Trip ID
     * @param int|null $userId User ID (current user if null)
     * @return array {can_review: bool, reason?: string}
     */
    public function canUserReview(int $tripId, ?int $userId = null): array
    {
        $userId = $userId ?? get_current_user_id();

        // Check if user is logged in
        $settings = SettingsService::getSettings();
        $requireLogin = $settings['reviews']['require_login'] ?? true;

        if ($requireLogin && !$userId) {
            return [
                'can_review' => false,
                'reason' => __('You must be logged in to leave a review.', 'yatra'),
            ];
        }

        // Check if user already reviewed
        if ($userId) {
            $existingReview = $this->reviewRepository->findByUserAndTrip($userId, $tripId);
            if ($existingReview) {
                return [
                    'can_review' => false,
                    'reason' => __('You have already reviewed this trip.', 'yatra'),
                    'existing_review_id' => (int) $existingReview->id,
                ];
            }
        }

        return ['can_review' => true];
    }

    /**
     * Get review statistics
     * 
     * @return array
     */
    public function getStats(): array
    {
        return $this->reviewRepository->getStats();
    }

    /**
     * Format review for API response
     * 
     * @param object $review Raw review data
     * @return array
     */
    private function formatReview(object $review): array
    {
        return [
            'id' => (int) $review->id,
            'trip_id' => (int) $review->trip_id,
            'trip_title' => $review->trip_title ?? null,
            'trip_slug' => $review->trip_slug ?? null,
            'user_id' => $review->user_id ? (int) $review->user_id : null,
            'user_display_name' => $review->user_display_name ?? null,
            'rating' => (int) $review->rating,
            'title' => $review->title ?? '',
            'content' => $review->content ?? '',
            'author_name' => $review->author_name ?? '',
            'author_email' => $review->author_email ?? '',
            'author_location' => $review->author_location ?? null,
            'status' => $review->status,
            'helpful_count' => (int) ($review->helpful_count ?? 0),
            'can_edit' => $review->user_id 
                ? $this->reviewRepository->canUserEdit((int) $review->id, (int) $review->user_id)
                : false,
            'created_at' => $review->created_at,
            'updated_at' => $review->updated_at,
        ];
    }

    /**
     * Update trip's cached rating values
     * 
     * @param int $tripId Trip ID
     */
    private function updateTripRatingCache(int $tripId): void
    {
        $averageRating = $this->reviewRepository->getAverageRating($tripId);
        $reviewCount = $this->reviewRepository->getReviewCount($tripId);

        // Trips table columns are avg_rating + reviews_count (not average_rating / review_count).
        $this->tripRepository->update($tripId, [
            'avg_rating' => $averageRating,
            'reviews_count' => $reviewCount,
        ]);
    }
}