<?php

namespace App\Modules\AI\Application;

use App\Modules\AI\Domain\AiProvider;
use App\Modules\AI\Infrastructure\AiEndpointPolicy;
use App\Modules\AI\Infrastructure\LocalStructuringProvider;
use App\Modules\AI\Infrastructure\OpenAiCompatibleProvider;
use Illuminate\Support\Facades\Crypt;
use Illuminate\Support\Facades\DB;
use RuntimeException;

final class AiProviderResolver
{
    public function __construct(
        private readonly LocalStructuringProvider $local,
        private readonly OpenAiCompatibleProvider $openAi,
        private readonly AiEndpointPolicy $endpointPolicy,
    ) {}

    public function forOrganization(string $organizationId): AiProvider
    {
        $connection = DB::table('ai_provider_connections')
            ->where('organization_id', $organizationId)
            ->where('enabled', true)
            ->orderByDesc('is_default')
            ->orderBy('created_at')
            ->orderBy('id')
            ->first();
        if ($connection) {
            return $this->fromConnection($connection);
        }
        $row = DB::table('organization_profiles')->where('organization_id', $organizationId)->first();
        $settings = json_decode($row?->settings ?: '{}', true);

        return ($settings['ai']['provider'] ?? 'local') === 'openai' ? $this->openAi : $this->local;
    }

    public function byId(string $id, string $organizationId): AiProvider
    {
        if (str_starts_with($id, 'connection:')) {
            $connection = DB::table('ai_provider_connections')
                ->where('organization_id', $organizationId)
                ->where('id', substr($id, 11))
                ->where('enabled', true)
                ->first();
            if ($connection) {
                return $this->fromConnection($connection);
            }

            throw new RuntimeException('The selected AI provider connection is unavailable.');
        }

        return match ($id) {
            'openai' => $this->openAi,
            'local', 'local-structuring-v1' => $this->local,
            default => throw new RuntimeException('The selected AI provider is unknown.'),
        };
    }

    public function fallbackForOrganization(string $organizationId, string $failedProviderId): ?AiProvider
    {
        $settings = $this->settings($organizationId);
        $enabled = (bool) ($settings['reliability']['fallbackEnabled'] ?? true);
        $fallback = $settings['fallbackProvider'] ?? 'local';

        $fallbackConnectionId = $settings['fallbackConnectionId'] ?? null;
        if ($enabled && $fallbackConnectionId && ! str_contains($failedProviderId, $fallbackConnectionId)) {
            $connection = DB::table('ai_provider_connections')->where('organization_id', $organizationId)->where('id', $fallbackConnectionId)->where('enabled', true)->first();
            if ($connection) {
                return $this->fromConnection($connection);
            }
        }

        return $enabled && $failedProviderId !== 'local' && $fallback === 'local' ? $this->local : null;
    }

    /** @return array<string, mixed> */
    public function status(string $organizationId): array
    {
        $provider = $this->forOrganization($organizationId);
        if ($provider instanceof OpenAiCompatibleProvider) {
            return ['id' => $provider->id(), 'external' => $provider->external(), 'configured' => $provider->configured(), ...$provider->health()];
        }

        return ['id' => $provider->id(), 'external' => false, 'configured' => true, 'connected' => true, 'latencyMs' => 0, 'message' => 'پردازش محلی آماده است.'];
    }

    /** @return array<string, mixed> */
    private function settings(string $organizationId): array
    {
        $row = DB::table('organization_profiles')->where('organization_id', $organizationId)->first();
        $settings = json_decode($row?->settings ?: '{}', true);

        return $settings['ai'] ?? [];
    }

    private function fromConnection(object $row): OpenAiCompatibleProvider
    {
        return new OpenAiCompatibleProvider($this->endpointPolicy, [
            'id' => $row->id, 'provider' => $row->provider, 'mode' => $row->mode, 'base_url' => $row->base_url,
            'api_key' => filled($row->encrypted_api_key) ? Crypt::decryptString($row->encrypted_api_key) : '',
            'default_model' => $row->default_model, 'timeout_seconds' => $row->timeout_seconds,
        ]);
    }
}