<?php
class Post_Formatter {
    private $api;
    private $max_length = 300;

    public function __construct($access_token, $did) {
        $this->api = new Bluesky_API($access_token, $did);
    }

    public function format_and_post($post) {
        $content = $this->get_formatted_content($post);
        
        $post_data = array(
            '$type' => 'app.bsky.feed.post',
            'text' => $content,
            'createdAt' => gmdate('c', strtotime($post->post_date_gmt)),
            'langs' => array('en')
        );

        // Add facets for the URL
        $post_data['facets'] = $this->parse_facets($post);

        // Handle image embed separately from text content
        if (has_post_thumbnail($post->ID)) {
            $image_data = $this->handle_featured_image($post->ID);
            if (!empty($image_data) && !isset($image_data['error'])) {
                $post_data['embed'] = $image_data;
            }
        }

        return $this->api->create_post($post_data);
    }

    private function get_formatted_content($post) {
        $format = get_option('bluesky_post_format', 'image-title-excerpt-link');
        $include_title = get_option('bluesky_include_title', true);
        
        // Get individual components
        $title = $include_title ? $post->post_title : '';
        $excerpt = $this->get_excerpt($post);
        $url = wp_get_shortlink($post->ID);
        
        // Start building content with explicit line breaks
        $content = '';
        
        // Add title with line break if it exists
        if (!empty($title)) {
            $content .= $title . "\n\n";
        }
        
        // Add excerpt if it exists
        if (!empty($excerpt)) {
            $content .= $excerpt . "\n\n";  // Add double line break after excerpt
        }
        
        // Add URL on its own line
        if (!empty($url)) {
            $content .= $url;  // URL starts on new line due to previous \n\n
        }

        return $content;
    }

    private function get_excerpt($post) {
        $text = wp_strip_all_tags($post->post_excerpt);
        if (empty($text)) {
            $text = wp_strip_all_tags($post->post_content);
        }
        
        $url = wp_get_shortlink($post->ID);
        $include_title = get_option('bluesky_include_title', true);
        
        // Calculate available length accounting for spacing and new lines
        $available_length = $this->max_length;
        $available_length -= strlen($url);
        $available_length -= 2; // Account for \n\n after excerpt
        
        if ($include_title) {
            $available_length -= strlen($post->post_title);
            $available_length -= 2; // Account for \n\n after title
        }
        
        if (mb_strlen($text) > $available_length) {
            $text = mb_substr($text, 0, $available_length - 3) . '...';
        }
        
        return $text;
    }

    private function parse_facets($post) {
        $facets = array();
        $content = $this->get_formatted_content($post);
        
        // Add link facet for the post URL
        $url = wp_get_shortlink($post->ID);
        $text_bytes = mb_convert_encoding($content, 'UTF-8');
        $url_position = mb_strrpos($text_bytes, $url);
        
        if ($url_position !== false) {
            $facets[] = array(
                'index' => array(
                    'byteStart' => $url_position,
                    'byteEnd' => $url_position + strlen($url),
                ),
                'features' => array(
                    array(
                        '$type' => 'app.bsky.richtext.facet#link',
                        'uri' => $url,
                    ),
                ),
            );
        }

        return $facets;
    }

    private function handle_featured_image($post_id) {
        $image_id = get_post_thumbnail_id($post_id);
        $image_path = get_attached_file($image_id);
        
        if (!$image_path) {
            return array('error' => 'Image file not found');
        }

        $mime_type = get_post_mime_type($image_id);
        
        // Get image data
        $image_data = file_get_contents($image_path);
        if ($image_data === false) {
            return array('error' => 'Failed to read image file');
        }

        // Check file size (1MB limit for Bluesky)
        if (strlen($image_data) > 1000000) {
            // If image is too large, attempt to resize it
            $resized = $this->resize_image($image_path);
            if ($resized) {
                $image_data = file_get_contents($resized);
                unlink($resized); // Clean up temporary file
            } else {
                return array('error' => 'Image file size exceeds 1MB limit and resize failed');
            }
        }

        // Upload image blob
        $response = $this->api->upload_blob($image_path, $mime_type);

        if (isset($response['error'])) {
            return $response;
        }

        // Get the alt text
        $alt_text = get_post_meta($image_id, '_wp_attachment_image_alt', true) ?: '';

        return array(
            '$type' => 'app.bsky.embed.images',
            'images' => array(
                array(
                    'alt' => $alt_text,
                    'image' => $response['blob'],
                ),
            ),
        );
    }

    private function resize_image($image_path) {
        // Only proceed if GD is available
        if (!function_exists('imagecreatefrompng')) {
            return false;
        }

        $mime_type = mime_content_type($image_path);
        list($width, $height) = getimagesize($image_path);
        
        // Calculate new dimensions while maintaining aspect ratio
        $max_dimension = 1000; // Reasonable size that should result in < 1MB file
        if ($width > $height) {
            $new_width = $max_dimension;
            $new_height = floor($height * ($max_dimension / $width));
        } else {
            $new_height = $max_dimension;
            $new_width = floor($width * ($max_dimension / $height));
        }

        // Create new image
        $new_image = imagecreatetruecolor($new_width, $new_height);

        // Handle different image types
        switch ($mime_type) {
            case 'image/jpeg':
                $source = imagecreatefromjpeg($image_path);
                break;
            case 'image/png':
                $source = imagecreatefrompng($image_path);
                // Preserve transparency
                imagealphablending($new_image, false);
                imagesavealpha($new_image, true);
                break;
            case 'image/gif':
                $source = imagecreatefromgif($image_path);
                break;
            default:
                return false;
        }

        if (!$source) {
            return false;
        }

        // Resize
        imagecopyresampled(
            $new_image, 
            $source, 
            0, 0, 0, 0, 
            $new_width, 
            $new_height, 
            $width, 
            $height
        );

        // Create temporary file
        $temp_file = tempnam(sys_get_temp_dir(), 'bluesky_img_');
        
        // Save resized image
        switch ($mime_type) {
            case 'image/jpeg':
                imagejpeg($new_image, $temp_file, 85);
                break;
            case 'image/png':
                imagepng($new_image, $temp_file, 8);
                break;
            case 'image/gif':
                imagegif($new_image, $temp_file);
                break;
        }

        // Clean up
        imagedestroy($source);
        imagedestroy($new_image);

        return $temp_file;
    }
}