<?php

class AIClientFactory
{

    public static function create($model, $config, $systemPrompt, $message, $history = [])
    {
        $instance = new self(); // 或 new MyClass();
        if ($model == 'claude') {
            return $instance->Claude37ClientSendMessage($config, $systemPrompt, $message, $history);
        } elseif ($model == 'deepseek') {
            return $instance->DeepSeekClientSendMessage($config, $systemPrompt, $message, $history);
        }
        return ['success' => false, 'error' => 'Invalid model'];
    }

    /**
     * Send a message to the Claude API
     * 
     * @param string $message The user message
     * @param array $history Previous conversation history
     * @return array The API response
     */
    private function Claude37ClientSendMessage($config, $systemPrompt, $message, $history = [])
    {
        // Format conversation history for Claude API
        //$messages = AIClientFactory::formatHistory($history);

        // Add the current user message
        $messages[] = [
            'role' => 'user',
            'content' => $message
        ];

        // Prepare request data
        $data = [
            'model' => $config['model'],
            'messages' => $messages,
            'system' => $systemPrompt,
            'max_tokens' => $config['max_tokens'],
            'temperature' => $config['temperature'],
            'top_p' => $config['top_p']
        ];

        // Prepare headers
        $headers = [
            'Content-Type: application/json',
            'x-api-key: ' . $config['api_key'],
            'anthropic-version: 2023-06-01'
        ];

        try {
            // Make the request
            $response = $this->makeRequest($config['api_url'], $data, $headers);

            // Extract the assistant's message
            if (isset($response['content']) && !empty($response['content'])) {
                $content = '';
                foreach ($response['content'] as $part) {
                    if ($part['type'] === 'text') {
                        $content .= $part['text'];
                    }
                }

                // Return formatted response
                return [
                    'success' => true,
                    'message' => $content,
                    'model' => 'claude',
                    'full_response' => $response
                ];
            } else {
                throw new Exception('Invalid response format from Claude API');
            }
        } catch (Exception $e) {
            // Log and return error
            error_log('Claude 3.7', $e->getMessage());

            return [
                'success' => false,
                'error' => $e->getMessage(),
                'model' => 'claude'
            ];
        }
    }

    /**
     * Send a message to the DeepSeek API
     *
     * @param string $message The user message
     * @param array $history Previous conversation history
     * @return array The API response
     */
    private function DeepSeekClientSendMessage($config, $systemPrompt, $message, $history = [])
    {
        // Format conversation history for DeepSeek API
        //$messages = $this->formatHistory($history);
        $messages = [];

        // Add system message at the beginning
        $messages = array_merge([
            ['role' => 'system', 'content' => $systemPrompt]
        ], $messages);

        // Add the current user message
        $messages[] = [
            'role' => 'user',
            'content' => $message
        ];

        // Prepare request data
        $data = [
            'model' => $config['model'],
            'messages' => $messages,
            'max_tokens' => $config['max_tokens'],
            'temperature' => $config['temperature'],
            'top_p' => $config['top_p']
        ];

        // Prepare headers
        $headers = [
            'Content-Type: application/json',
            'Authorization: Bearer ' . $config['api_key']
        ];

        try {
            // Make the request
            $response = $this->makeRequest($config['api_url'], $data, $headers);

            // Extract the assistant's message
            if (isset($response['choices'][0]['message']['content'])) {
                $content = $response['choices'][0]['message']['content'];

                // Return formatted response
                return [
                    'success' => true,
                    'message' => $content,
                    'model' => 'deepseek',
                    'full_response' => $response
                ];
            } else {
                throw new Exception('Invalid response format from DeepSeek API');
            }
        } catch (Exception $e) {
            // Log and return error
            error_log('DeepSeek', $e->getMessage());

            return [
                'success' => false,
                'error' => $e->getMessage(),
                'model' => 'deepseek'
            ];
        }
    }


    private function makeRequest($url, $data, $headers = [])
    {
        $ch = curl_init($url);

        // Set common cURL options
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($data));
        curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);

        // Send the request
        $response = curl_exec($ch);
        $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        $error = curl_error($ch);

        curl_close($ch);

        // Handle errors
        if ($error) {
            error_log("cURL error: $url, $error");
            throw new Exception("API request failed: $error");
        }

        // Decode response
        $responseData = json_decode($response, true);

        if ($httpCode >= 400) {
            $errorMsg = isset($responseData['error']['message'])
                ? $responseData['error']['message']
                : "HTTP error code: $httpCode";

            error_log($url, $errorMsg, $responseData);
            throw new Exception("API error: $errorMsg");
        }

        return $responseData;
    }

    /* Format conversation history for Claude API
    * 
    * @param array $history Conversation history
    * @return array Formatted history
    */
    private function formatHistory($history)
    {
        $messages = [];

        foreach ($history as $item) {
            if ($item['role'] === 'user') {
                $messages[] = [
                    'role' => 'user',
                    'content' => $item['content']
                ];
            } elseif ($item['role'] === 'assistant') {
                $messages[] = [
                    'role' => 'assistant',
                    'content' => $item['content']
                ];
            }
        }

        return $messages;
    }
}