<?php

namespace app\common\service\ai;

use app\common\model\ai\AiConfig;

class EmbeddingClient
{
    private const DASHSCOPE_BASE_URL = 'https://dashscope.aliyuncs.com/compatible-mode';
    private const DASHSCOPE_EMBEDDING_MODEL = 'text-embedding-v4';

    protected string $apiKey;
    protected string $baseUrl;
    protected string $model;
    protected int $defaultDim;

    public function __construct()
    {
        $this->apiKey = (string) (AiConfig::getVal('embedding_api_key', '') ?: env('DASHSCOPE_API_KEY', ''));
        $this->baseUrl = (string) (AiConfig::getVal('embedding_base_url', '') ?: self::DASHSCOPE_BASE_URL);
        $this->model = (string) (AiConfig::getVal('embedding_model', '') ?: self::DASHSCOPE_EMBEDDING_MODEL);
        $this->defaultDim = (int) (AiConfig::getVal('embedding_dim', '') ?: '1024');
    }

    /**
     * @param string|array<int, string> $input
     */
    public function embed($input, array $options = []): array
    {
        $apiKey = $options['api_key'] ?? $this->apiKey;
        $baseUrl = rtrim($options['base_url'] ?? $this->baseUrl, '/');
        $model = $options['model'] ?? $this->model;

        if ($apiKey === '' || $baseUrl === '' || $model === '') {
            return [
                'success' => false,
                'error' => 'Embedding API配置未完成',
                'embeddings' => [],
                'cost_ms' => 0,
            ];
        }

        $payload = [
            'model' => $model,
            'input' => $input,
        ];

        if (!empty($options['dimensions'])) {
            $payload['dimensions'] = (int) $options['dimensions'];
        } elseif ($this->defaultDim > 0) {
            $payload['dimensions'] = $this->defaultDim;
        }

        $startTime = microtime(true);
        $ch = curl_init($baseUrl . '/v1/embeddings');
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_HTTPHEADER => [
                'Content-Type: application/json',
                'Authorization: Bearer ' . $apiKey,
            ],
            CURLOPT_POSTFIELDS => json_encode($payload, JSON_UNESCAPED_UNICODE),
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_TIMEOUT => 60,
            CURLOPT_SSL_VERIFYPEER => false,
        ]);

        $response = curl_exec($ch);
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $error = curl_error($ch);
        curl_close($ch);

        $costMs = (int) ((microtime(true) - $startTime) * 1000);
        if ($error) {
            return [
                'success' => false,
                'error' => 'Embedding cURL错误: ' . $error,
                'embeddings' => [],
                'cost_ms' => $costMs,
            ];
        }

        $data = json_decode((string) $response, true);
        if ($httpCode !== 200 || empty($data['data']) || !is_array($data['data'])) {
            return [
                'success' => false,
                'error' => $data['error']['message'] ?? ('HTTP ' . $httpCode),
                'embeddings' => [],
                'cost_ms' => $costMs,
            ];
        }

        $embeddings = [];
        foreach ($data['data'] as $row) {
            $embedding = $row['embedding'] ?? [];
            if (is_array($embedding) && !empty($embedding)) {
                $embeddings[] = array_map('floatval', $embedding);
            }
        }

        return [
            'success' => !empty($embeddings),
            'error' => !empty($embeddings) ? '' : 'Embedding结果为空',
            'embeddings' => $embeddings,
            'model' => $model,
            'dimension' => count($embeddings[0] ?? []),
            'tokens' => (int) ($data['usage']['total_tokens'] ?? 0),
            'cost_ms' => $costMs,
        ];
    }
}