<?php
if (!defined('ABSPATH')) exit;

class AIWEST_Content_Engine {
    public static function generate_post($topic, $keyword = '', $status = 'draft', $length = 'medium', $source = 'manual', $media_options = []) {
        $media_options = self::sanitize_media_options($media_options);
        $history_id = 0;
        if (class_exists('AIWEST_History')) {
            $history_id = AIWEST_History::add_content($source, $topic, $keyword, $topic);
        }

        $task_id = AIWEST_Tasks::add('create_post', compact('topic','keyword','status','length','source','media_options'), 'safe');
        $taxonomy_instruction = get_option('aiwest_auto_taxonomy', 'yes') === 'yes'
            ? __("Also add fields: category and tags. Category must be one main WordPress category. Tags must be an array of 3-8 tags.\n", 'ai-webmaster-studio')
            : "";
        $media_instruction = $media_options['action'] === 'ai'
            ? __("Also add field image_prompt: a short, precise AI image generation prompt, with no text on the image.\n", 'ai-webmaster-studio')
            : "";

        $messages = [
            ['role' => 'system', 'content' => AIWEST_OpenAI::system_prompt()],
            ['role' => 'user', 'content' =>
                "Write a complete SEO article for WordPress. Default content language: ".AIWEST_Languages::language_name(AIWEST_Languages::content_locale()).". Use a different language only when explicitly requested.\n" .
                __("Topic: ", 'ai-webmaster-studio') . $topic . "\n" . __("Keyword: ", 'ai-webmaster-studio') . $keyword . "\n" . __("Length: ", 'ai-webmaster-studio') . $length . "\n" .
                __("Return the result as JSON with fields: title, excerpt, meta_title, meta_description, html_content.\n", 'ai-webmaster-studio') .
                $taxonomy_instruction .
                $media_instruction .
                __("HTML must be clean and semantic, without markdown or ``` fences. Do not add an H1 or repeat the post title as the first heading. Start with an introduction, then use H2/H3.", 'ai-webmaster-studio') . "\n\n" .
                (class_exists('AIWEST_Search_Optimization') ? AIWEST_Search_Optimization::prompt_contract(['post_type'=>'post']) : '')]
        ];

        $result = AIWEST_OpenAI::chat($messages, 0.5);
        if (is_wp_error($result)) {
            AIWEST_Tasks::complete($task_id, ['error' => $result->get_error_message()]);
            if ($history_id) AIWEST_History::update_content($history_id, 'error', null, $result->get_error_message());
            return $result;
        }

        $clean = trim($result);
        $clean = preg_replace('/^```json\s*/i', '', $clean);
        $clean = preg_replace('/^```\s*/', '', $clean);
        $clean = preg_replace('/\s*```$/', '', $clean);
        $data = json_decode($clean, true);
        if (!is_array($data)) {
            $first = strpos($clean, '{'); $last = strrpos($clean, '}');
            if ($first !== false && $last !== false && $last > $first) {
                $data = json_decode(substr($clean, $first, $last - $first + 1), true);
            }
        }

        if (!is_array($data) || empty($data['title']) || empty($data['html_content'])) {
            $msg = __('AI did not return a valid JSON format.', 'ai-webmaster-studio');
            AIWEST_Tasks::complete($task_id, ['error' => $msg, 'raw_excerpt' => wp_trim_words(wp_strip_all_tags($result), 80, '...')]);
            if ($history_id) AIWEST_History::update_content($history_id, 'error', null, $msg);
            return new WP_Error('invalid_ai_json', $msg);
        }

        $allowed_status = in_array($status, ['draft', 'publish'], true) ? $status : 'draft';
        if ($allowed_status === 'publish' && get_option('aiwest_auto_publish_posts') !== 'yes') $allowed_status = 'draft';
        if (class_exists('AIWEST_Technical_Operator')) {
            $allowed_status = AIWEST_Technical_Operator::default_post_status($allowed_status);
            $aiwest_operator_decision = AIWEST_Technical_Operator::explain_decision('create_post', 'content_post_create', ['post_type' => 'post', 'post_status' => $allowed_status]);
        } else {
            $aiwest_operator_decision = [];
        }

        $post_title = sanitize_text_field($data['title']);
        $post_content = wp_kses_post($data['html_content']);
        $heading_normalization = ['content' => $post_content, 'report' => []];
        if (class_exists('AIWEST_Page_Title_Heading_Normalizer')) {
            $heading_normalization = AIWEST_Page_Title_Heading_Normalizer::normalize(0, $post_content, [
                'post_title' => $post_title,
                'post_type' => 'post',
                'mode' => 'standard',
                'theme_title_visible' => true,
            ]);
            $post_content = $heading_normalization['content'];
        }

        $post_id = wp_insert_post([
            'post_title' => $post_title,
            'post_excerpt' => sanitize_textarea_field($data['excerpt'] ?? ''),
            'post_content' => $post_content,
            'post_status' => $allowed_status,
            'post_type' => 'post',
            'post_author' => class_exists('AIWEST_Technical_Operator') ? AIWEST_Technical_Operator::post_author_id(get_current_user_id()) : (get_current_user_id() ?: 1),
        ], true);

        if (is_wp_error($post_id)) {
            AIWEST_Tasks::complete($task_id, ['error' => $post_id->get_error_message()]);
            if ($history_id) AIWEST_History::update_content($history_id, 'error', null, $post_id->get_error_message());
            return $post_id;
        }

        $taxonomy_result = self::assign_ai_taxonomy($post_id, $data);
        update_post_meta($post_id, '_aiwest_meta_title', sanitize_text_field($data['meta_title'] ?? ''));
        update_post_meta($post_id, '_aiwest_meta_description', sanitize_textarea_field($data['meta_description'] ?? ''));
        update_post_meta($post_id, '_aiwest_generated', 'yes');
        update_post_meta($post_id, '_aiwest_source', sanitize_text_field($source));
        update_post_meta($post_id, '_aiwest_taxonomy_result', $taxonomy_result);
        update_post_meta($post_id, '_aiwest_media_options', $media_options);
        $search_report = class_exists('AIWEST_Search_Optimization') ? AIWEST_Search_Optimization::finalize($post_id, $post_content, ['post_type'=>'post','post_title'=>$post_title], $data) : [];
        if (class_exists('AIWEST_Page_Title_Heading_Normalizer')) {
            AIWEST_Page_Title_Heading_Normalizer::record_report($post_id, $heading_normalization['report']);
        }
        if (class_exists('AIWEST_Technical_Operator')) {
            AIWEST_Technical_Operator::annotate_post($post_id, 'create_post', $aiwest_operator_decision);
        }

        $media_result = self::handle_media($post_id, $data, $topic, $keyword, $media_options);
        update_post_meta($post_id, '_aiwest_media_result', $media_result);

        AIWEST_Tasks::complete($task_id, [
            'post_id' => $post_id,
            'status' => $allowed_status,
            'source' => $source,
            'taxonomy' => $taxonomy_result,
            'media' => $media_result,
            'search_optimization' => $search_report,
        ]);
        AIWEST_Logger::info('AI content generated.', ['post_id' => $post_id, 'topic' => $topic, 'source' => $source, 'taxonomy' => $taxonomy_result, 'media' => $media_result]);

        if ($history_id) {
            $msg = $allowed_status === 'publish'
                ? __('The post was published.', 'ai-webmaster-studio')
                : __('The post was created as a draft.', 'ai-webmaster-studio');

            if (!empty($taxonomy_result['category'])) {
                $msg .= ' ' . sprintf(
                    /* translators: %s: Assigned WordPress category name. */
                    __('Category: %s.', 'ai-webmaster-studio'),
                    $taxonomy_result['category']
                );
            }
            if (!empty($taxonomy_result['tags'])) {
                $msg .= ' ' . sprintf(
                    /* translators: %s: Comma-separated list of assigned WordPress tags. */
                    __('Tags: %s.', 'ai-webmaster-studio'),
                    implode(', ', $taxonomy_result['tags'])
                );
            }
            if (!empty($media_result['message'])) $msg .= ' ' . $media_result['message'];
            AIWEST_History::update_content($history_id, 'completed', $post_id, $msg);
        }
        return $post_id;
    }

    public static function sanitize_media_options($options) {
        $options = is_array($options) ? $options : [];
        if (class_exists('AIWEST_Graphics_Rules')) {
            return AIWEST_Graphics_Rules::resolve($options);
        }

        $action = sanitize_key($options['action'] ?? 'site_default');
        if (!in_array($action, ['site_default', 'none', 'ai', 'library'], true)) {
            $action = 'site_default';
        }

        $placement = sanitize_key($options['placement'] ?? 'featured');
        if (!in_array($placement, ['featured', 'content_top', 'featured_and_content_top'], true)) {
            $placement = 'featured';
        }

        $size = sanitize_text_field($options['size'] ?? '1024x1024');
        if (!in_array($size, ['1024x1024', '1536x1024', '1024x1536'], true)) {
            $size = '1024x1024';
        }

        return [
            'action' => $action,
            'placement' => $placement,
            'size' => $size,
            'generation_size' => $size,
            'display_size' => 'large',
            'custom_width' => 800,
            'custom_height' => 0,
            'alignment' => 'none',
            'mobile_behavior' => 'full_width',
            'replace_existing' => 'no',
            'attachment_id' => absint($options['attachment_id'] ?? 0),
            'auto_select_library' => sanitize_key($options['auto_select_library'] ?? 'no') === 'yes' ? 'yes' : 'no',
            'prompt' => sanitize_textarea_field($options['prompt'] ?? ''),
        ];
    }

    public static function handle_media_for_existing_post($post_id, $media_options, $context = '') {
        $post_id = absint($post_id);
        if (!$post_id || !get_post($post_id)) {
            return new WP_Error('aiwest_missing_post', __('The post or page was not found.', 'ai-webmaster-studio'));
        }

        $post = get_post($post_id);
        $data = [
            'image_prompt' => $context ?: wp_trim_words(wp_strip_all_tags($post->post_content), 60, '...'),
        ];
        $result = self::handle_media($post_id, $data, $post->post_title, '', $media_options);
        update_post_meta($post_id, '_aiwest_media_result', $result);
        update_post_meta($post_id, '_aiwest_media_options', self::sanitize_media_options($media_options));
        return $result;
    }

    protected static function handle_media($post_id, $data, $topic, $keyword, $media_options) {
        $media_options = self::sanitize_media_options($media_options);
        $action = $media_options['action'];

        if ($action === 'none') {
            return ['status' => 'skipped', 'message' => __('Image: skipped according to administrator rules.', 'ai-webmaster-studio'), 'attachment_id' => 0];
        }

        if ($action === 'site_default') {
            $action = 'none';
        }

        if ($action === 'library') {
            $attachment_id = absint($media_options['attachment_id']);
            $auto_selected = false;
            if (!$attachment_id && sanitize_key($media_options['auto_select_library'] ?? 'no') === 'yes') {
                $attachment_id = self::select_library_image($post_id, $topic, $keyword, $data);
                $auto_selected = $attachment_id > 0;
                if ($auto_selected) {
                    $media_options['attachment_id'] = $attachment_id;
                }
            }
            if (!$attachment_id) {
                return ['status' => 'error', 'message' => __('Image: Media Library was selected, but no suitable image is available for automatic use.', 'ai-webmaster-studio'), 'attachment_id' => 0];
            }
            if (!wp_attachment_is_image($attachment_id)) {
                return ['status' => 'error', 'message' => __('Image: the selected file is not a valid image.', 'ai-webmaster-studio'), 'attachment_id' => 0];
            }

            $applied = self::apply_attachment_to_post($post_id, $attachment_id, $media_options['placement'], array_merge($media_options, ['action' => 'library', 'source' => 'library']));
            if (!$applied) {
                return ['status' => 'error', 'message' => __('Image: the Media Library image could not be applied.', 'ai-webmaster-studio'), 'attachment_id' => 0];
            }

            return [
                'status' => 'attached',
                'message' => $auto_selected
                    ? __('A Media Library image was selected automatically and added according to administrator rules.', 'ai-webmaster-studio')
                    : __('The Media Library image was added using the selected source and placement.', 'ai-webmaster-studio'),
                'attachment_id' => $attachment_id,
                'source' => 'library',
                'auto_selected' => $auto_selected ? 'yes' : 'no',
                'placement' => $media_options['placement'],
                'display_size' => $media_options['display_size'] ?? 'large',
            ];
        }

        if ($action === 'ai') {
            if (!class_exists('AIWEST_Image_Generator')) {
                return ['status' => 'error', 'message' => __('Image: the AI image generation module is unavailable.', 'ai-webmaster-studio'), 'attachment_id' => 0];
            }

            if (!AIWEST_Image_Generator::enabled()) {
                return ['status' => 'skipped', 'message' => __('Image: AI generation is disabled in settings.', 'ai-webmaster-studio'), 'attachment_id' => 0];
            }

            $image_context = $media_options['prompt'] ?: (($data['image_prompt'] ?? '') ?: ($topic . ' ' . $keyword));
            $image = AIWEST_Image_Generator::generate_for_post($post_id, $image_context, $media_options);
            if (is_wp_error($image)) {
                return [
                    'status' => 'error',
                    'message' => sprintf(
                        /* translators: %s: Error message returned by the image generation service. */
                        __('Image error: %s', 'ai-webmaster-studio'),
                        $image->get_error_message()
                    ),
                    'attachment_id' => 0,
                ];
            }
            return [
                'status' => 'generated',
                'message' => __('The AI image was added according to the image rules.', 'ai-webmaster-studio'),
                'attachment_id' => intval($image),
                'source' => 'ai',
                'placement' => $media_options['placement'],
                'size' => $media_options['generation_size'] ?? $media_options['size'],
                'display_size' => $media_options['display_size'] ?? 'large',
            ];
        }

        return ['status' => 'skipped', 'message' => '', 'attachment_id' => 0];
    }

    protected static function select_library_image($post_id, $topic = '', $keyword = '', $data = []) {
        $post_id = absint($post_id);
        $search_terms = trim(wp_strip_all_tags((string) ($keyword ?: $topic)));
        $search_terms = preg_replace('/\s+/', ' ', $search_terms);

        $base_args = [
            'post_type' => 'attachment',
            'post_status' => 'inherit',
            'post_mime_type' => 'image',
            'numberposts' => 12,
            'orderby' => 'date',
            'order' => 'DESC',
            'fields' => 'ids',
        ];

        $candidate_ids = [];
        if ($search_terms !== '') {
            $search_args = $base_args;
            $search_args['s'] = wp_trim_words($search_terms, 8, '');
            $candidate_ids = get_posts($search_args);
        }

        if (!$candidate_ids) {
            $candidate_ids = get_posts($base_args);
        }

        if (!$candidate_ids || !is_array($candidate_ids)) {
            return 0;
        }

        $valid_ids = [];
        foreach ($candidate_ids as $candidate_id) {
            $candidate_id = absint($candidate_id);
            if ($candidate_id && wp_attachment_is_image($candidate_id)) {
                $valid_ids[] = $candidate_id;
            }
        }

        if (!$valid_ids) {
            return 0;
        }

        $index = $post_id ? ($post_id % count($valid_ids)) : 0;
        return absint($valid_ids[$index]);
    }

    public static function apply_attachment_to_post($post_id, $attachment_id, $placement = 'featured', $options = []) {
        $post_id = absint($post_id);
        $attachment_id = absint($attachment_id);
        $placement = sanitize_key($placement);
        $options = is_array($options) ? $options : [];
        if (class_exists('AIWEST_Graphics_Rules')) {
            $options = AIWEST_Graphics_Rules::sanitize(array_merge($options, ['placement' => $placement]), true);
            $placement = sanitize_key($options['placement'] ?? $placement);
        }

        if (!$post_id || !$attachment_id || !wp_attachment_is_image($attachment_id)) {
            return false;
        }

        $replace_existing = sanitize_key($options['replace_existing'] ?? 'no') === 'yes';

        if (in_array($placement, ['featured', 'featured_and_content_top'], true)) {
            if ($replace_existing || !get_post_thumbnail_id($post_id)) {
                set_post_thumbnail($post_id, $attachment_id);
                update_post_meta($post_id, '_aiwest_featured_image_id', $attachment_id);
            }
        }

        if (in_array($placement, ['content_top', 'featured_and_content_top', 'after_first_paragraph', 'content_end'], true)) {
            $post = get_post($post_id);
            if ($post) {
                $wp_size = class_exists('AIWEST_Graphics_Rules') ? AIWEST_Graphics_Rules::wp_image_size($options) : 'large';
                $attrs = class_exists('AIWEST_Graphics_Rules') ? AIWEST_Graphics_Rules::image_attrs($options) : ['class' => 'aiwest-content-image', 'loading' => 'lazy'];
                $image_html = wp_get_attachment_image($attachment_id, $wp_size, false, $attrs);
                if ($image_html) {
                    $figure_class = class_exists('AIWEST_Graphics_Rules') ? AIWEST_Graphics_Rules::figure_class($options) : 'wp-block-image size-large aiwest-generated-media';
                    $figure = '<figure class="' . esc_attr($figure_class) . '">' . $image_html . '</figure>' . "\n\n";
                    $content = $post->post_content;

                    if ($placement === 'content_end') {
                        $content = self::append_inline_media_at_content_end($content, $figure);
                    } elseif ($placement === 'after_first_paragraph') {
                        $parts = preg_split('/(<\/p>)/i', $content, 2, PREG_SPLIT_DELIM_CAPTURE);
                        if (is_array($parts) && count($parts) >= 3) {
                            $content = $parts[0] . $parts[1] . "\n\n" . $figure . $parts[2];
                        } else {
                            $content = $figure . $content;
                        }
                    } else {
                        $content = $figure . $content;
                    }

                    wp_update_post([
                        'ID' => $post_id,
                        'post_content' => $content,
                    ]);
                    update_post_meta($post_id, '_aiwest_inline_image_id', $attachment_id);
                    update_post_meta($post_id, '_aiwest_inline_image_placement', $placement);
                    update_post_meta($post_id, '_aiwest_inline_image_source', sanitize_key($options['source'] ?? ($options['action'] ?? '')));
                }
            }
        }

        return true;
    }

    protected static function append_inline_media_at_content_end($content, $figure) {
        $content = (string) $content;
        $figure = "\n\n" . trim((string) $figure) . "\n\n";

        // Keep AIW images inside the AI-generated wrapper when possible. This makes
        // "end of content" mean the end of the article text, not a position after
        // theme/plugin related-post sections rendered outside post_content.
        if (stripos($content, '<div class="aiwest-generated-content"') !== false) {
            $last_close = strripos($content, '</div>');
            if ($last_close !== false) {
                return substr($content, 0, $last_close) . $figure . substr($content, $last_close);
            }
        }

        return rtrim($content) . $figure;
    }

    public static function assign_ai_taxonomy($post_id, $data) {
        $out = ['enabled' => get_option('aiwest_auto_taxonomy', 'yes') === 'yes', 'category' => '', 'tags' => []];
        if (!$out['enabled']) return $out;

        $category = sanitize_text_field($data['category'] ?? '');
        if ($category) {
            $term = term_exists($category, 'category');
            if (!$term) $term = wp_insert_term($category, 'category');
            if (!is_wp_error($term)) {
                $term_id = is_array($term) ? intval($term['term_id']) : intval($term);
                if ($term_id) { wp_set_post_categories($post_id, [$term_id], false); $out['category'] = $category; }
            }
        }

        $tags = $data['tags'] ?? [];
        if (is_string($tags)) $tags = array_map('trim', explode(',', $tags));
        if (is_array($tags)) {
            $clean_tags = [];
            foreach ($tags as $tag) {
                $tag = sanitize_text_field($tag);
                if ($tag && mb_strlen($tag) <= 80) $clean_tags[] = $tag;
            }
            $clean_tags = array_values(array_unique(array_slice($clean_tags, 0, 8)));
            if ($clean_tags) { wp_set_post_tags($post_id, $clean_tags, false); $out['tags'] = $clean_tags; }
        }
        return $out;
    }
}