<?php

namespace App\Services;

use App\Models\Category;
use App\Models\User;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Facades\Storage;

class WhatsAppBusinessService
{
    /**
     * Check whether WhatsApp Business API is configured.
     *
     * @return bool
     */
    public function isConfigured()
    {
        return filled(config('services.whatsapp.token'))
            && filled(config('services.whatsapp.phone_number_id'))
            && filled($this->adminRecipient());
    }

    /**
     * Send a car notification to the admin via WhatsApp Cloud API.
     *
     * @param \App\Models\Category $category
     * @param \App\Models\User|null $customer
     * @return array<string, mixed>
     */
    public function sendCarNotificationToAdmin(Category $category, ?User $customer = null)
    {
        if (!$this->isConfigured()) {
            return [
                'success' => false,
                'message' => 'WhatsApp Business API belum dikonfigurasi.',
            ];
        }

        $recipient = $this->formatPhoneNumber($this->adminRecipient());
        $endpoint = $this->graphEndpoint('messages');

        $imageUrl = $this->getCarImageUrl($category);
        $mediaId = $this->uploadCarImage($category);
        $canSendImage = filled($mediaId) || $this->isPublicMediaUrl($imageUrl);
        $caption = $this->buildCaption($category, $customer, $canSendImage);

        $payload = [
            'messaging_product' => 'whatsapp',
            'recipient_type' => 'individual',
            'to' => $recipient,
            'type' => $canSendImage ? 'image' : 'text',
        ];

        if ($mediaId) {
            $payload['image'] = [
                'id' => $mediaId,
                'caption' => $caption,
            ];
        } elseif ($canSendImage) {
            $payload['image'] = [
                'link' => $imageUrl,
                'caption' => $caption,
            ];
        } else {
            $payload['text'] = [
                'preview_url' => false,
                'body' => $caption,
            ];
        }

        $response = Http::withToken(config('services.whatsapp.token'))
            ->acceptJson()
            ->post($endpoint, $payload);

        if ($response->successful()) {
            return [
                'success' => true,
                'message' => $canSendImage
                    ? 'Notifikasi gambar katalog mobil berhasil dikirim ke admin.'
                    : 'Notifikasi teks berhasil dikirim ke admin.',
                'data' => $response->json(),
            ];
        }

        Log::warning('Gagal mengirim WhatsApp Business notification.', [
            'category_id' => $category->id,
            'status' => $response->status(),
            'response' => $response->json() ?: $response->body(),
        ]);

        return [
            'success' => false,
            'message' => 'Gagal mengirim notifikasi WhatsApp Business ke admin.',
            'error' => $response->json() ?: $response->body(),
        ];
    }

    /**
     * Build message caption sent to admin.
     *
     * @param \App\Models\Category $category
     * @param \App\Models\User|null $customer
     * @param bool $withImage
     * @return string
     */
    private function buildCaption(Category $category, ?User $customer = null, $withImage = true)
    {
        $lines = [
            'Customer tertarik dengan mobil katalog ini.',
            'Mobil: ' . $category->name,
            'Harga: Rp ' . number_format((float) $category->price, 0, ',', '.'),
            'Tahun: ' . ($category->year ?: '-'),
        ];

        if ($customer) {
            $lines[] = 'Username customer: ' . $customer->username;
            $lines[] = 'Email customer: ' . $customer->email;
            if ($customer->phone_number) {
                $lines[] = 'No. HP customer: ' . $customer->phone_number;
            }
        } else {
            $lines[] = 'Customer: pengunjung belum login';
        }

        $detailUrl = route('mobil-bekas.detail', ['category' => $category->id]);
        $lines[] = 'Link detail: ' . $detailUrl;
        if (!$withImage) {
            $lines[] = 'Link foto katalog: ' . ($this->getCarImageUrl($category) ?: '-');
            $lines[] = 'Catatan: gambar dikirim sebagai teks karena file katalog belum bisa dikirim sebagai media.';
        }

        return implode("\n", $lines);
    }

    /**
     * Upload the local catalog image to WhatsApp and return its media ID.
     *
     * @param \App\Models\Category $category
     * @return string|null
     */
    private function uploadCarImage(Category $category)
    {
        if (!$category->image || !Storage::disk('public')->exists($category->image)) {
            return null;
        }

        $path = Storage::disk('public')->path($category->image);
        $mimeType = Storage::disk('public')->mimeType($category->image) ?: 'image/jpeg';

        if (!str_starts_with($mimeType, 'image/')) {
            return null;
        }

        $handle = fopen($path, 'r');

        if (!$handle) {
            return null;
        }

        try {
            $response = Http::withToken(config('services.whatsapp.token'))
                ->acceptJson()
                ->attach('file', $handle, basename($path), ['Content-Type' => $mimeType])
                ->post($this->graphEndpoint('media'), [
                    'messaging_product' => 'whatsapp',
                    'type' => $mimeType,
                ]);
        } finally {
            fclose($handle);
        }

        if ($response->successful()) {
            return $response->json('id');
        }

        Log::warning('Gagal upload media WhatsApp Business.', [
            'category_id' => $category->id,
            'status' => $response->status(),
            'response' => $response->json() ?: $response->body(),
        ]);

        return null;
    }

    /**
     * Get admin WhatsApp recipient from the dedicated WhatsApp setting,
     * with fallback to the existing direct chat number.
     *
     * @return string|null
     */
    private function adminRecipient()
    {
        return config('services.whatsapp.admin_recipient');
    }

    /**
     * Get a public absolute image URL if the car has an image.
     *
     * @param \App\Models\Category $category
     * @return string|null
     */
    private function getCarImageUrl(Category $category)
    {
        if (!$category->image) {
            return null;
        }

        return $this->publicUrl(Storage::disk('public')->url($category->image));
    }

    /**
     * Check whether the media URL is public enough for WhatsApp to fetch.
     *
     * @param string|null $url
     * @return bool
     */
    private function isPublicMediaUrl($url)
    {
        if (!$url) {
            return false;
        }

        return !str_contains($url, 'localhost')
            && !str_contains($url, '127.0.0.1');
    }

    /**
     * Build an absolute URL from APP_URL so the Cloud API can fetch media.
     *
     * @param string $path
     * @return string
     */
    private function publicUrl($path)
    {
        if (filter_var($path, FILTER_VALIDATE_URL)) {
            return $path;
        }

        return rtrim(config('app.url'), '/') . '/' . ltrim($path, '/');
    }

    /**
     * Build WhatsApp Graph API endpoint for the configured phone number.
     *
     * @param string $path
     * @return string
     */
    private function graphEndpoint($path)
    {
        return rtrim(config('services.whatsapp.base_url'), '/')
            . '/'
            . config('services.whatsapp.api_version')
            . '/'
            . config('services.whatsapp.phone_number_id')
            . '/'
            . ltrim($path, '/');
    }

    /**
     * Normalize phone number to WhatsApp format.
     *
     * @param string $phoneNumber
     * @return string
     */
    private function formatPhoneNumber($phoneNumber)
    {
        $phoneNumber = preg_replace('/[^0-9]/', '', $phoneNumber);

        if (strlen($phoneNumber) === 10 && substr($phoneNumber, 0, 1) === '8') {
            return '62' . $phoneNumber;
        }

        if (strlen($phoneNumber) >= 11 && substr($phoneNumber, 0, 2) === '08') {
            return '62' . substr($phoneNumber, 1);
        }

        if (substr($phoneNumber, 0, 2) !== '62') {
            return '62' . $phoneNumber;
        }

        return $phoneNumber;
    }
}