<?php

namespace app\common\tools\ai\provider;

use app\common\tools\ai\AiProviderInterface;

/**
 * OpenAI 兼容适配器.
 *
 * 适用于所有兼容 OpenAI API 格式的供应商:
 * OpenAI / Zhipu / DeepSeek / Moonshot / Qwen / etc.
 */
class OpenAiCompatibleAdapter implements AiProviderInterface
{
    /**
     * @var string 供应商标识(如 zhipu, deepseek)
     */
    protected $providerId;

    /**
     * @var string 供应商显示名称
     */
    protected $providerName;

    /**
     * @param string $providerId   供应商标识
     * @param string $providerName 显示名称(可选)
     */
    public function __construct(string $providerId, string $providerName = '')
    {
        $this->providerId = $providerId;
        $this->providerName = $providerName ?: ucfirst($providerId);
    }

    /**
     * {@inheritdoc}
     */
    public function chat(string $systemPrompt, string $userPrompt, array $options = []): string
    {
        $apiKey = get_system_config("ai_provider_{$this->providerId}_key", '');
        $baseUrl = get_system_config("ai_provider_{$this->providerId}_base_url", 'https://api.openai.com/v1');
        $model = $options['model'] ?? get_system_config('ai_default_model', 'gpt-3.5-turbo');

        $url = rtrim($baseUrl, '/') . '/chat/completions';
        $data = [
            'model' => $model,
            'messages' => [
                ['role' => 'system', 'content' => $systemPrompt],
                ['role' => 'user', 'content' => $userPrompt],
            ],
        ];

        if (isset($options['temperature'])) {
            $data['temperature'] = (float) $options['temperature'];
        }
        if (isset($options['max_tokens'])) {
            $data['max_tokens'] = (int) $options['max_tokens'];
        }

        $response = $this->httpPost($url, $data, [
            'Authorization: Bearer ' . $apiKey,
            'Content-Type: application/json',
        ]);

        if ($response === false) {
            return '';
        }

        $result = json_decode($response, true);
        if (!$result || isset($result['error'])) {
            return '';
        }

        return $result['choices'][0]['message']['content'] ?? '';
    }

    /**
     * {@inheritdoc}
     */
    public function chatJson(string $systemPrompt, string $userPrompt, array $options = []): array
    {
        $jsonInstruction = "\n\n请严格按照JSON格式返回结果，不要包含任何其他文字说明。";
        $content = $this->chat($systemPrompt . $jsonInstruction, $userPrompt, $options);

        if (empty($content)) {
            return [];
        }

        // 尝试提取JSON内容(可能包裹在markdown代码块中)
        if (preg_match('/```(?:json)?\s*([\s\S]*?)```/', $content, $matches)) {
            $content = $matches[1];
        }

        $decoded = json_decode(trim($content), true);

        return is_array($decoded) ? $decoded : [];
    }

    /**
     * {@inheritdoc}
     */
    public function getProviderName(): string
    {
        return $this->providerName;
    }

    /**
     * {@inheritdoc}
     */
    public function getModels(): array
    {
        $apiKey = get_system_config("ai_provider_{$this->providerId}_key", '');
        $baseUrl = get_system_config("ai_provider_{$this->providerId}_base_url", 'https://api.openai.com/v1');

        if (empty($apiKey)) {
            return [];
        }

        $url = rtrim($baseUrl, '/') . '/models';
        $response = $this->httpGet($url, [
            'Authorization: Bearer ' . $apiKey,
        ]);

        if ($response === false) {
            return [];
        }

        $result = json_decode($response, true);
        if (!$result || !isset($result['data'])) {
            return [];
        }

        $models = [];
        foreach ($result['data'] as $model) {
            $models[] = [
                'id' => $model['id'] ?? '',
                'name' => $model['id'] ?? '',
                'owned_by' => $model['owned_by'] ?? '',
            ];
        }

        return $models;
    }

    /**
     * {@inheritdoc}
     */
    public function testConnection(): bool
    {
        $apiKey = get_system_config("ai_provider_{$this->providerId}_key", '');
        if (empty($apiKey)) {
            return false;
        }

        try {
            $result = $this->chat(
                'You are a test assistant.',
                'Reply with exactly: OK',
                ['max_tokens' => 5]
            );

            return !empty($result);
        } catch (\Exception $e) {
            return false;
        }
    }

    /**
     * HTTP POST 请求.
     *
     * @param string $url     请求地址
     * @param array  $data    请求数据
     * @param array  $headers 请求头
     *
     * @return string|false
     */
    protected function httpPost(string $url, array $data, array $headers = [])
    {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_TIMEOUT, 60);

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

        if ($httpCode >= 400) {
            return false;
        }

        return $response;
    }

    /**
     * HTTP GET 请求.
     *
     * @param string $url     请求地址
     * @param array  $headers 请求头
     *
     * @return string|false
     */
    protected function httpGet(string $url, array $headers = [])
    {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
        curl_setopt($ch, CURLOPT_TIMEOUT, 30);

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

        if ($httpCode >= 400) {
            return false;
        }

        return $response;
    }
}