<?php

namespace App\Http\Controllers;

use App\Enums\WaProvider;
use App\Models\SystemSetting;
use App\Models\WaProviderConfig;
use App\Models\WaStorefront;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Auth;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Log;

/**
 * WABA Embedded Signup callback — front-end posts the OAuth `code`
 * + the `phone_number_id` + `waba_id` + `business_id` it received
 * from FB.login. We exchange the code for an access token, subscribe
 * Meta's webhook, register the phone, link a catalog, and write the
 * wa_provider_configs row marked 'connected'.
 */
class WaConnectWabaController extends Controller
{
    public function complete(Request $request): JsonResponse
    {
        $data = $request->validate([
            'code'             => 'required|string|max:1024',
            'phone_number_id'  => 'required|string|max:64',
            'waba_id'          => 'required|string|max:64',
            'business_id'      => 'nullable|string|max:64',
        ]);

        $appId     = (string) SystemSetting::get('waba_app_id', '');
        $appSecret = (string) SystemSetting::get('waba_app_secret', '');
        if ($appId === '' || $appSecret === '') {
            return response()->json(['ok' => false, 'message' => 'Meta App credentials not configured.'], 422);
        }

        // Graph API version — single source of truth (admin setting), so this
        // Embedded-Signup probe tracks the same version as every other Meta
        // call (default v23.0). It was hardcoded to v22.0 and drifted behind.
        $gv = (string) SystemSetting::get('waba_graph_api_version', 'v23.0');

        // 1. Exchange code → access_token
        try {
            $tokenRes = Http::timeout(10)->get("https://graph.facebook.com/{$gv}/oauth/access_token", [
                'client_id'     => $appId,
                'client_secret' => $appSecret,
                'code'          => $data['code'],
            ]);
            if (!$tokenRes->successful() || !$tokenRes->json('access_token')) {
                return response()->json([
                    'ok' => false,
                    'message' => 'Could not exchange code: ' . ($tokenRes->json('error.message') ?? $tokenRes->status()),
                ], 422);
            }
            $accessToken = $tokenRes->json('access_token');
        } catch (\Throwable $e) {
            return response()->json(['ok' => false, 'message' => 'Token exchange failed: ' . $e->getMessage()], 500);
        }

        $errors = [];

        // 2. Subscribe to webhook events on the WABA
        try {
            $sub = Http::withToken($accessToken)
                ->timeout(10)
                ->post("https://graph.facebook.com/{$gv}/{$data['waba_id']}/subscribed_apps");
            if (!$sub->successful()) {
                $errors['subscribe'] = $sub->json('error.message') ?? 'unknown';
            }
        } catch (\Throwable $e) {
            $errors['subscribe'] = $e->getMessage();
        }

        // 3. Register the phone number on Cloud API
        $pin = str_pad((string) random_int(0, 999999), 6, '0', STR_PAD_LEFT);
        try {
            $reg = Http::withToken($accessToken)
                ->timeout(10)
                ->post("https://graph.facebook.com/{$gv}/{$data['phone_number_id']}/register", [
                    'messaging_product' => 'whatsapp',
                    'pin'               => $pin,
                ]);
            if (!$reg->successful()) {
                $errors['register'] = $reg->json('error.message') ?? 'unknown';
            }
        } catch (\Throwable $e) {
            $errors['register'] = $e->getMessage();
        }

        // 4. Pull phone display number for our records
        $displayPhone = null;
        try {
            $info = Http::withToken($accessToken)
                ->timeout(10)
                ->get("https://graph.facebook.com/{$gv}/{$data['phone_number_id']}", [
                    'fields' => 'display_phone_number,verified_name',
                ]);
            $displayPhone = $info->json('display_phone_number');
        } catch (\Throwable $e) { /* optional */ }

        // 5. Auto-create or link a catalog (best effort)
        $catalogId = null;
        try {
            // List existing catalogs first; reuse if already linked
            $list = Http::withToken($accessToken)
                ->timeout(10)
                ->get("https://graph.facebook.com/{$gv}/{$data['waba_id']}/product_catalogs");
            if ($list->successful() && !empty($list->json('data.0.id'))) {
                $catalogId = $list->json('data.0.id');
            } elseif (!empty($data['business_id'])) {
                $create = Http::withToken($accessToken)
                    ->timeout(10)
                    ->post("https://graph.facebook.com/{$gv}/{$data['business_id']}/owned_product_catalogs", [
                        'name'     => \App\Models\SystemSetting::get('app_name', config('app.name', 'WaDesk')) . ' auto · ' . now()->format('Y-m-d'),
                        'vertical' => 'commerce',
                    ]);
                if ($create->successful()) {
                    $catalogId = $create->json('id');
                    Http::withToken($accessToken)
                        ->timeout(10)
                        ->post("https://graph.facebook.com/{$gv}/{$data['waba_id']}/product_catalogs", [
                            'catalog_id' => $catalogId,
                        ]);
                }
            }
        } catch (\Throwable $e) {
            $errors['catalog'] = $e->getMessage();
        }

        // 6. Persist
        $user = Auth::user();
        $workspaceId = $user->current_workspace_id;
        if (!$workspaceId) {
            return response()->json(['ok' => false, 'message' => 'No active workspace.'], 422);
        }

        $config = WaProviderConfig::firstOrNew(['workspace_id' => $workspaceId]);
        $config->fill([
            'provider'      => WaProvider::Waba->value,
            'status'        => empty($errors) ? WaProviderConfig::STATUS_CONNECTED : WaProviderConfig::STATUS_FAILED,
            'phone_number'  => $displayPhone,
            'display_label' => 'WABA · ' . ($displayPhone ?: $data['phone_number_id']),
            'connected_at'  => now(),
            'is_primary'    => true,
            'meta_json'     => array_filter([
                'waba_id'         => $data['waba_id'],
                'phone_number_id' => $data['phone_number_id'],
                'business_id'     => $data['business_id'] ?? null,
                'catalog_id'      => $catalogId,
                'errors'          => $errors ?: null,
            ]),
        ]);
        $config->setCreds([
            'access_token'         => $accessToken,
            'phone_number_id'      => $data['phone_number_id'],
            'waba_id'              => $data['waba_id'],
            'business_id'          => $data['business_id'] ?? null,
            'register_pin'         => $pin,
            'catalog_id'           => $catalogId,
            'webhook_verify_token' => SystemSetting::get('waba_webhook_verify_token', ''),
        ]);
        $config->save();

        // Demote any other provider rows for this workspace so
        // WorkspaceEngine::for() resolves to WABA immediately. Same
        // reasoning as the Twilio/Baileys saves — a previous row marked
        // primary would otherwise keep the old engine sticky.
        WaProviderConfig::where('workspace_id', $workspaceId)
            ->where('id', '!=', $config->id)
            ->update(['is_primary' => false]);
        \App\Services\WorkspaceEngine::flush();

        WaStorefront::firstOrCreate(['workspace_id' => $workspaceId], ['theme_key' => WaStorefront::DEFAULT_THEME]);

        return response()->json([
            'ok'         => empty($errors),
            'errors'     => $errors,
            'phone'      => $displayPhone,
            'catalog_id' => $catalogId,
            'redirect'   => url('/store'),
        ]);
    }
}
