<?php
if (!defined('ABSPATH')) {
    exit; // Prevent direct access
}

/**
 * Moderate a WordPress comment using AI (OpenAI + ChatGPT).
 *
 * @param int $comment_ID The ID of the comment to moderate.
 * @return array {
 *   @type string 'decision'   The moderation decision (Approved, Spam, or fallback).
 *   @type string 'category'   The detected category.
 *   @type string 'confidence' The numeric confidence plus '%'.
 *   @type string 'error'      If something fails.
 * }
 */
function aicomo_moderate_comment($comment_ID) {
    try {
        // 1?? Validate & Retrieve the comment
        $comment_ID = intval($comment_ID);
        $comment = get_comment($comment_ID);
        if (!$comment) {
            return ['error' => __('Comment not found.', 'ai-powered-comment-moderator')];
        }

        // 2?? Sanitize content
        $comment_text = sanitize_text_field($comment->comment_content);

        // 3?? Retrieve OpenAI API key & settings
        $api_key = sanitize_text_field(get_option('aicomo_api_key'));
        $model   = sanitize_text_field(get_option('aicomo_model', 'gpt-4-turbo'));
        $prompt  = get_option('aicomo_system_prompt', '');

        // 4?? Use default moderation prompt if none is set
        if (empty($prompt)) {
            $prompt = 'You are an AI comment moderator. '
                . 'Your task is to determine if a comment is meaningful or spam/inappropriate. '
                . 'If the comment is nonsensical, offensive, or spam, respond with: '
                . 'Decision: No, Category: e.g. "Spam" or "Nonsensical", Confidence: <0-100>. '
                . 'If the comment makes sense, respond with: Decision: Yes, Category: e.g. "Legitimate", Confidence: <0-100>. '
                . 'Use exactly this format: Decision: [Yes/No]\nCategory: [string]\nConfidence: [integer]. '
                . 'No additional text.';
        }

        // 5?? OpenAI Moderation Endpoint Check (Optional)
        $moderation_response = wp_remote_post('https://api.openai.com/v1/moderations', [
            'body'    => wp_json_encode(['input' => $comment_text]),
            'headers' => [
                'Content-Type'  => 'application/json',
                'Authorization' => 'Bearer ' . $api_key,
            ],
            'timeout' => 15
        ]);

        if (is_wp_error($moderation_response)) {
            return ['error' => __('AI Moderation API request failed.', 'ai-powered-comment-moderator')];
        }

        $moderation_body = json_decode(wp_remote_retrieve_body($moderation_response), true);

        // ?? If OpenAI flags it, assume it's spam
        if (!empty($moderation_body['results'][0]['flagged'])) {
            if (function_exists('wp_spam_comment')) {
                wp_spam_comment($comment_ID);
            }
            return [
                'decision'   => __('Spam - AI Flagged', 'ai-powered-comment-moderator'),
                'category'   => 'Flagged',
                'confidence' => '99%'
            ];
        }

        // 6?? ChatGPT AI Review
        $request_body = [
            'model' => $model,
            'messages' => [
                [ 'role' => 'system', 'content' => $prompt ],
                [ 'role' => 'user',   'content' => $comment_text ],
            ],
            'temperature' => 0, // Consistency in responses
        ];

        $response = wp_remote_post('https://api.openai.com/v1/chat/completions', [
            'body'    => wp_json_encode($request_body),
            'headers' => [
                'Content-Type'  => 'application/json',
                'Authorization' => 'Bearer ' . $api_key,
            ],
            'timeout' => 15
        ]);

        if (is_wp_error($response)) {
            return ['error' => __('ChatGPT API request failed.', 'ai-powered-comment-moderator')];
        }

        $body = json_decode(wp_remote_retrieve_body($response), true);
        if (empty($body['choices'][0]['message']['content'])) {
            return ['error' => __('Invalid ChatGPT API response.', 'ai-powered-comment-moderator')];
        }

        // 7?? Extract AI response
        $message_content = strtolower(trim($body['choices'][0]['message']['content']));
        preg_match('/decision:\\s*(yes|no)/i', $message_content, $decision_match);
        preg_match('/category:\\s*([a-zA-Z ]+)/i', $message_content, $category_match);
        preg_match('/confidence:\\s*(\\d+)/i', $message_content, $confidence_match);

        $decision   = (!empty($decision_match[1]) && strtolower($decision_match[1]) === 'yes');
        $category   = (!empty($category_match[1])) ? trim($category_match[1]) : 'Uncategorized';
        $confidence = (!empty($confidence_match[1])) ? intval($confidence_match[1]) : 0;

        // ? FINAL DECISION LOGIC

        if ($decision) { 
            // ?? AI says it's a valid comment -> APPROVE IT
            wp_update_comment([
                'comment_ID'      => $comment_ID,
                'comment_approved' => 1
            ]);

            return [
            /* translators: %s represents the detected category by AI (e.g., "Uncategorized", "Spam", etc.) */
                'decision'   => __('Approved', 'ai-powered-comment-moderator'),
                'category'   => $category,
                'confidence' => $confidence . '%'
            ];
        } else {
            // ? If confidence is HIGH (=70) -> MARK AS SPAM
            if ($confidence >= 70) {
                if (function_exists('wp_spam_comment')) {
                    wp_spam_comment($comment_ID);
                }
                return [
                 /* translators: %s represents the detected category by AI (e.g., "Uncategorized", "Spam", etc.) */
                    'decision'   => sprintf(__('Spam - %s', 'ai-powered-comment-moderator'), $category),
                    'category'   => $category,
                    'confidence' => $confidence . '%'
                ];
            } else {
                // ? If confidence is LOW (<70) -> NEEDS REVIEW
                return [
                 /* translators: %s represents the detected category by AI (e.g., "Uncategorized", "Spam", etc.) */
                    'decision'   => sprintf(__('Needs Review - %s', 'ai-powered-comment-moderator'), $category),
                    'category'   => $category,
                    'confidence' => $confidence . '%'
                ];
            }
        }

    } catch (Exception $e) {
        return ['error' => __('An unexpected error occurred.', 'ai-powered-comment-moderator')];
    }
}