<?php
/**
 * Image Manager Class
 *
 * Handles image generation, variant management, and WordPress Media integration.
 *
 * @package WP_Agentic_Writer
 * @since 0.1.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Image Manager class.
 */
class WP_Agentic_Writer_Image_Manager {

	/**
	 * Singleton instance.
	 *
	 * @var WP_Agentic_Writer_Image_Manager
	 */
	private static $instance = null;

	/**
	 * Get singleton instance.
	 *
	 * @return WP_Agentic_Writer_Image_Manager
	 */
	public static function get_instance() {
		if ( null === self::$instance ) {
			self::$instance = new self();
		}
		return self::$instance;
	}

	/**
	 * Constructor.
	 */
	private function __construct() {
		// Private constructor for singleton.
	}

	/**
	 * Create database tables on plugin activation.
	 */
	public function create_tables() {
		global $wpdb;

		$charset_collate = $wpdb->get_charset_collate();

		// Table 1: wp_wpaw_images
		$table_images = $wpdb->prefix . 'wpaw_images';
		$sql_images   = "CREATE TABLE IF NOT EXISTS `{$table_images}` (
			`id` bigint(20) NOT NULL AUTO_INCREMENT,
			`post_id` bigint(20) NOT NULL,
			`agent_image_id` varchar(50) NOT NULL,
			`placement` varchar(100) DEFAULT NULL,
			`section_title` varchar(255) DEFAULT NULL,
			`prompt_initial` text NOT NULL,
			`alt_text_initial` text DEFAULT NULL,
			`prompt_edited` text DEFAULT NULL,
			`alt_text_edited` text DEFAULT NULL,
			`attachment_id` bigint(20) DEFAULT NULL,
			`status` varchar(30) DEFAULT 'pending',
			`cost_estimate` decimal(10, 4) DEFAULT NULL,
			`cost_actual` decimal(10, 4) DEFAULT NULL,
			`image_model` varchar(100) DEFAULT NULL,
			`created_at` datetime DEFAULT CURRENT_TIMESTAMP NOT NULL,
			`updated_at` datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP NOT NULL,
			PRIMARY KEY (`id`),
			KEY `idx_post` (`post_id`),
			KEY `idx_agent_image_id` (`post_id`, `agent_image_id`),
			KEY `idx_status` (`status`),
			KEY `idx_created` (`created_at`)
		) {$charset_collate};";

		// Table 2: wp_wpaw_images_variants
		$table_variants = $wpdb->prefix . 'wpaw_images_variants';
		$sql_variants   = "CREATE TABLE IF NOT EXISTS `{$table_variants}` (
			`id` bigint(20) NOT NULL AUTO_INCREMENT,
			`agentic_image_id` bigint(20) NOT NULL,
			`post_id` bigint(20) NOT NULL,
			`agent_image_id` varchar(50) NOT NULL,
			`variant_number` int(11) DEFAULT 1,
			`temp_file_path` varchar(500) NOT NULL,
			`temp_file_url` varchar(500) NOT NULL,
			`file_size` int(11) DEFAULT NULL,
			`prompt_used` text DEFAULT NULL,
			`image_model_used` varchar(100) DEFAULT NULL,
			`generation_time` int(11) DEFAULT NULL,
			`cost` decimal(10, 4) DEFAULT NULL,
			`is_selected` tinyint(1) DEFAULT 0,
			`selected_at` datetime DEFAULT NULL,
			`status` varchar(30) DEFAULT 'temp',
			`created_at` datetime DEFAULT CURRENT_TIMESTAMP NOT NULL,
			`deleted_at` datetime DEFAULT NULL,
			PRIMARY KEY (`id`),
			KEY `idx_agentic_image` (`agentic_image_id`),
			KEY `idx_post` (`post_id`),
			KEY `idx_status` (`status`),
			KEY `idx_created` (`created_at`)
		) {$charset_collate};";

		require_once ABSPATH . 'wp-admin/includes/upgrade.php';
		dbDelta( $sql_images );
		dbDelta( $sql_variants );

		// Create temp directory.
		$this->create_temp_directory();
	}

	/**
	 * Create temp directory for image storage.
	 */
	private function create_temp_directory() {
		$upload_dir = wp_upload_dir();
		$temp_dir   = $upload_dir['basedir'] . '/wpaw';

		if ( ! file_exists( $temp_dir ) ) {
			wp_mkdir_p( $temp_dir );

			// Add .htaccess to prevent direct access.
			$htaccess = $temp_dir . '/.htaccess';
			if ( ! file_exists( $htaccess ) ) {
				file_put_contents( $htaccess, "Options -Indexes\n" );
			}

			// Add index.php for security.
			$index = $temp_dir . '/index.php';
			if ( ! file_exists( $index ) ) {
				file_put_contents( $index, "<?php // Silence is golden\n" );
			}
		}
	}

	/**
	 * Analyze article for optimal image placement.
	 *
	 * @param string $article_markdown Article content in markdown.
	 * @param int    $post_id Post ID.
	 * @return array|WP_Error Placement data or error.
	 */
	public function analyze_article_for_images( $article_markdown, $post_id ) {
		$settings      = get_option( 'wp_agentic_writer_settings', array() );
		$writing_model = $settings['writing_model'] ?? 'anthropic/claude-3.5-sonnet';

		$system_prompt = "You are an expert content strategist analyzing articles for optimal image placement.

Your task: Identify 2-3 strategic locations where images would enhance understanding and engagement.

RULES:
1. Prioritize placement after introduction (hero image)
2. Consider complex sections that need visual aids
3. Look for opportunities before conclusions
4. Maximum 3 images per article

Return JSON:
{
  \"recommended_image_count\": 3,
  \"image_placement_points\": [
    {
      \"agent_image_id\": \"img_hero_1\",
      \"placement\": \"after_introduction\",
      \"section_title\": \"Introduction\",
      \"image_type\": \"hero_dashboard\",
      \"reasoning\": \"Sets visual tone for article\"
    }
  ]
}";

		$messages = array(
			array(
				'role'    => 'user',
				'content' => "Analyze this article for image placement:\n\n" . $article_markdown,
			),
		);

		$provider = WP_Agentic_Writer_Provider_Manager::get_provider_for_task( 'planning' );
		$response = $provider->chat( $messages, array( 'temperature' => 0.3 ), 'planning' );

		if ( is_wp_error( $response ) ) {
			return $response;
		}

		// Extract JSON from response.
		$json_match = array();
		if ( preg_match( '/\{[\s\S]*\}/m', $response['content'], $json_match ) ) {
			$placement_data = json_decode( $json_match[0], true );
			if ( JSON_ERROR_NONE === json_last_error() ) {
				return $placement_data;
			}
		}

		return new WP_Error( 'parse_error', 'Failed to parse placement analysis' );
	}

	/**
	 * Generate image prompts optimized for specific image model.
	 *
	 * @param string $article_markdown Article content.
	 * @param array  $placement_data Placement analysis.
	 * @param int    $post_id Post ID.
	 * @return array|WP_Error Image specifications or error.
	 */
	public function generate_image_prompts( $article_markdown, $placement_data, $post_id ) {
		$settings      = get_option( 'wp_agentic_writer_settings', array() );
		$writing_model = $settings['writing_model'] ?? 'anthropic/claude-3.5-sonnet';
		$image_model   = $settings['image_model'] ?? 'openai/gpt-4o';

		// Get model-specific prompt guidance.
		$prompt_guidance = $this->get_prompt_guidance_for_model( $image_model );

		$system_prompt = "You are an Image Prompt Engineer specializing in {$prompt_guidance['model_name']}.

TARGET MODEL: {$prompt_guidance['model_name']}
PROMPT LENGTH: {$prompt_guidance['prompt_length']}
COMPLEXITY: {$prompt_guidance['complexity']}

{$prompt_guidance['guidance']}

TEMPLATE: {$prompt_guidance['template']}

Generate precise, cost-efficient prompts that exploit this model's strengths.

Return JSON:
{
  \"images\": [
    {
      \"agent_image_id\": \"img_hero_1\",
      \"placement\": \"after_introduction\",
      \"section_title\": \"Introduction\",
      \"prompt\": \"[Model-optimized prompt]\",
      \"alt\": \"Descriptive alt text\",
      \"image_model\": \"{$image_model}\"
    }
  ]
}";

		$user_input = wp_json_encode(
			array(
				'article'           => $article_markdown,
				'placement_points'  => $placement_data['image_placement_points'],
				'image_count'       => $placement_data['recommended_image_count'],
				'target_image_model' => $image_model,
			)
		);

		$messages = array(
			array(
				'role'    => 'user',
				'content' => "Generate image prompts:\n\n" . $user_input,
			),
		);

		$provider = WP_Agentic_Writer_Provider_Manager::get_provider_for_task( 'planning' );
		$response = $provider->chat( $messages, array( 'temperature' => 0.7 ), 'planning' );

		if ( is_wp_error( $response ) ) {
			return $response;
		}

		// Extract JSON.
		$json_match = array();
		if ( preg_match( '/\{[\s\S]*\}/m', $response['content'], $json_match ) ) {
			$image_specs = json_decode( $json_match[0], true );
			if ( JSON_ERROR_NONE === json_last_error() ) {
				// Save to database.
				$this->save_image_recommendations( $post_id, $image_specs['images'] );
				return $image_specs;
			}
		}

		return new WP_Error( 'parse_error', 'Failed to parse image prompts' );
	}

	/**
	 * Get prompt guidance for specific image model.
	 *
	 * @param string $image_model Image model ID.
	 * @return array Model configuration.
	 */
	private function get_prompt_guidance_for_model( $image_model ) {
		$model_configs = array(
			'black-forest-labs/flux.2-klein' => array(
				'model_name'    => 'FLUX.2 [klein]',
				'prompt_length' => '1-2 sentences',
				'complexity'    => 'simple',
				'guidance'      => 'Keep prompts short and simple. Focus on main subject, key details, and style. Avoid complex scenes or technical specifications.',
				'template'      => 'Subject, key elements, style, color palette',
			),
			'sourceful/riverflow-v2-max'     => array(
				'model_name'    => 'Riverflow V2 Max',
				'prompt_length' => '3-4 sentences',
				'complexity'    => 'medium-detailed',
				'guidance'      => 'Include context, environment details, lighting style, and photographic specifications. Model excels at photorealism.',
				'template'      => 'Subject + context, environment details, lighting style, photography style, technical specs',
			),
			'black-forest-labs/flux.2-max'   => array(
				'model_name'    => 'FLUX.2 [max]',
				'prompt_length' => '4-6 sentences',
				'complexity'    => 'very-detailed-technical',
				'guidance'      => 'Use detailed technical vocabulary. Include exact materials, color codes (HEX), spatial relationships, and specifications.',
				'template'      => 'Technical foundation, main subject + action, environment, lighting + mood, style + aesthetics, technical specifications',
			),
		);

		// Default to Riverflow if model not found.
		return $model_configs[ $image_model ] ?? $model_configs['sourceful/riverflow-v2-max'];
	}

	/**
	 * Save image recommendations to database.
	 *
	 * @param int   $post_id Post ID.
	 * @param array $images Image specifications.
	 */
	private function save_image_recommendations( $post_id, $images ) {
		global $wpdb;
		$table = $wpdb->prefix . 'wpaw_images';

		foreach ( $images as $image_spec ) {
			$wpdb->insert(
				$table,
				array(
					'post_id'          => $post_id,
					'agent_image_id'   => $image_spec['agent_image_id'],
					'placement'        => $image_spec['placement'],
					'section_title'    => $image_spec['section_title'],
					'prompt_initial'   => $image_spec['prompt'],
					'alt_text_initial' => $image_spec['alt'],
					'image_model'      => $image_spec['image_model'],
					'status'           => 'pending',
				),
				array( '%d', '%s', '%s', '%s', '%s', '%s', '%s', '%s' )
			);
		}
	}

	/**
	 * Save single image recommendation to database.
	 *
	 * @param int    $post_id        Post ID.
	 * @param string $agent_image_id Unique image identifier.
	 * @param string $placement      Placement location.
	 * @param string $section_title  Section title.
	 * @param string $prompt         Image prompt/description.
	 * @param string $alt_text       Alt text for image.
	 * @return int|false Insert ID or false on failure.
	 */
	public function save_image_recommendation( $post_id, $agent_image_id, $placement, $section_title, $prompt, $alt_text ) {
		global $wpdb;
		$table = $wpdb->prefix . 'wpaw_images';

		$settings    = get_option( 'wp_agentic_writer_settings', array() );
		$image_model = $settings['image_model'] ?? 'openai/gpt-4o';

		$result = $wpdb->insert(
			$table,
			array(
				'post_id'          => $post_id,
				'agent_image_id'   => $agent_image_id,
				'placement'        => $placement,
				'section_title'    => $section_title,
				'prompt_initial'   => $prompt,
				'alt_text_initial' => $alt_text,
				'image_model'      => $image_model,
				'status'           => 'pending',
			),
			array( '%d', '%s', '%s', '%s', '%s', '%s', '%s', '%s' )
		);

		if ( $result ) {
			return $wpdb->insert_id;
		}

		return false;
	}

	/**
	 * Get image recommendations for a post.
	 *
	 * @param int $post_id Post ID.
	 * @return array Image recommendations.
	 */
	public function get_image_recommendations( $post_id ) {
		global $wpdb;
		$table = $wpdb->prefix . 'wpaw_images';

		$results = $wpdb->get_results(
			$wpdb->prepare(
				"SELECT * FROM {$table} WHERE post_id = %d ORDER BY created_at ASC",
				$post_id
			),
			ARRAY_A
		);

		return $results;
	}

	/**
	 * Generate image variants.
	 *
	 * @param int    $post_id Post ID.
	 * @param string $agent_image_id Agent image ID.
	 * @param string $prompt Image prompt.
	 * @param int    $variant_count Number of variants to generate.
	 * @return array|WP_Error Generated variants or error.
	 */
	public function generate_image_variants( $post_id, $agent_image_id, $prompt, $variant_count = 2 ) {
		$settings    = get_option( 'wp_agentic_writer_settings', array() );
		$image_model = $settings['image_model'] ?? 'openai/gpt-4o';

		$provider = WP_Agentic_Writer_Provider_Manager::get_provider_for_task( 'image' );

		$variants = array();

		for ( $i = 1; $i <= $variant_count; $i++ ) {
			$result = $provider->generate_image(
				$prompt,
				$image_model,
				array(
					'size'    => '1024x576',
					'quality' => 'hd',
					'n'       => 1,
				)
			);

			if ( is_wp_error( $result ) ) {
				return $result;
			}

			// Download image to temp directory.
			$temp_file = $this->download_temp_image( $post_id, $agent_image_id, $result['url'], $i );

			if ( is_wp_error( $temp_file ) ) {
				return $temp_file;
			}

			// Save variant to database.
			$variant_id = $this->save_variant(
				$post_id,
				$agent_image_id,
				$i,
				$temp_file,
				$prompt,
				$image_model,
				$result
			);

			$variants[] = array(
				'id'                => $variant_id,
				'variant_number'    => $i,
				'temp_file_url'     => $temp_file['url'],
				'cost'              => $result['cost'],
				'generation_time'   => $result['generation_time'],
				'image_model_used'  => $image_model,
			);
		}

		return $variants;
	}

	/**
	 * Download image to temp directory.
	 *
	 * @param int    $post_id Post ID.
	 * @param string $agent_image_id Agent image ID.
	 * @param string $image_url Image URL.
	 * @param int    $variant_number Variant number.
	 * @return array|WP_Error File info or error.
	 */
	private function download_temp_image( $post_id, $agent_image_id, $image_url, $variant_number ) {
		$upload_dir = wp_upload_dir();
		$temp_dir   = $upload_dir['basedir'] . '/wpaw/' . $post_id;

		if ( ! file_exists( $temp_dir ) ) {
			wp_mkdir_p( $temp_dir );
		}

		// Download image.
		$response = wp_remote_get( $image_url, array( 'timeout' => 30 ) );

		if ( is_wp_error( $response ) ) {
			return $response;
		}

		$image_data = wp_remote_retrieve_body( $response );

		// Determine file extension from content type.
		$content_type = wp_remote_retrieve_header( $response, 'content-type' );
		$extension    = 'jpg';
		if ( strpos( $content_type, 'png' ) !== false ) {
			$extension = 'png';
		}

		$filename = sprintf(
			'%s_variant_%d_%d.%s',
			$agent_image_id,
			$variant_number,
			time(),
			$extension
		);

		$file_path = $temp_dir . '/' . $filename;
		file_put_contents( $file_path, $image_data );

		$file_url = $upload_dir['baseurl'] . '/wpaw/' . $post_id . '/' . $filename;

		return array(
			'path' => $file_path,
			'url'  => $file_url,
			'size' => filesize( $file_path ),
		);
	}

	/**
	 * Save variant to database.
	 *
	 * @param int    $post_id Post ID.
	 * @param string $agent_image_id Agent image ID.
	 * @param int    $variant_number Variant number.
	 * @param array  $temp_file Temp file info.
	 * @param string $prompt Prompt used.
	 * @param string $image_model Image model used.
	 * @param array  $generation_result Generation result.
	 * @return int Variant ID.
	 */
	private function save_variant( $post_id, $agent_image_id, $variant_number, $temp_file, $prompt, $image_model, $generation_result ) {
		global $wpdb;

		// Get agentic_image_id from wp_wpaw_images.
		$table_images     = $wpdb->prefix . 'wpaw_images';
		$agentic_image_id = $wpdb->get_var(
			$wpdb->prepare(
				"SELECT id FROM {$table_images} WHERE post_id = %d AND agent_image_id = %s",
				$post_id,
				$agent_image_id
			)
		);

		$table_variants = $wpdb->prefix . 'wpaw_images_variants';

		$wpdb->insert(
			$table_variants,
			array(
				'agentic_image_id' => $agentic_image_id,
				'post_id'          => $post_id,
				'agent_image_id'   => $agent_image_id,
				'variant_number'   => $variant_number,
				'temp_file_path'   => $temp_file['path'],
				'temp_file_url'    => $temp_file['url'],
				'file_size'        => $temp_file['size'],
				'prompt_used'      => $prompt,
				'image_model_used' => $image_model,
				'generation_time'  => $generation_result['generation_time'],
				'cost'             => $generation_result['cost'],
				'status'           => 'temp',
			),
			array( '%d', '%d', '%s', '%d', '%s', '%s', '%d', '%s', '%s', '%d', '%f', '%s' )
		);

		return $wpdb->insert_id;
	}

	/**
	 * Commit image variant to WordPress Media Library.
	 *
	 * @param int    $post_id Post ID.
	 * @param string $agent_image_id Agent image ID.
	 * @param int    $variant_id Variant ID.
	 * @param string $alt_text Alt text.
	 * @return array|WP_Error Attachment info or error.
	 */
	public function commit_image_variant( $post_id, $agent_image_id, $variant_id, $alt_text ) {
		global $wpdb;

		// Get variant info.
		$table_variants = $wpdb->prefix . 'wpaw_images_variants';
		$variant        = $wpdb->get_row(
			$wpdb->prepare(
				"SELECT * FROM {$table_variants} WHERE id = %d",
				$variant_id
			),
			ARRAY_A
		);

		if ( ! $variant ) {
			return new WP_Error( 'variant_not_found', 'Variant not found' );
		}

		// Upload to Media Library.
		require_once ABSPATH . 'wp-admin/includes/image.php';
		require_once ABSPATH . 'wp-admin/includes/file.php';
		require_once ABSPATH . 'wp-admin/includes/media.php';

		$file_array = array(
			'name'     => basename( $variant['temp_file_path'] ),
			'tmp_name' => $variant['temp_file_path'],
		);

		$attachment_id = media_handle_sideload( $file_array, $post_id );

		if ( is_wp_error( $attachment_id ) ) {
			return $attachment_id;
		}

		// Set alt text.
		update_post_meta( $attachment_id, '_wp_attachment_image_alt', sanitize_text_field( $alt_text ) );

		// Update wp_wpaw_images table.
		$table_images = $wpdb->prefix . 'wpaw_images';
		$wpdb->update(
			$table_images,
			array(
				'attachment_id' => $attachment_id,
				'status'        => 'committed',
			),
			array(
				'post_id'        => $post_id,
				'agent_image_id' => $agent_image_id,
			),
			array( '%d', '%s' ),
			array( '%d', '%s' )
		);

		// Mark variant as selected.
		$wpdb->update(
			$table_variants,
			array(
				'is_selected' => 1,
				'selected_at' => current_time( 'mysql' ),
				'status'      => 'selected',
			),
			array( 'id' => $variant_id ),
			array( '%d', '%s', '%s' ),
			array( '%d' )
		);

		$attachment_url = wp_get_attachment_url( $attachment_id );

		return array(
			'attachment_id'  => $attachment_id,
			'attachment_url' => $attachment_url,
			'alt'            => $alt_text,
		);
	}

	/**
	 * Cleanup old temp images (7+ days old).
	 */
	public function cleanup_old_temp_images() {
		global $wpdb;

		$table_variants = $wpdb->prefix . 'wpaw_images_variants';

		// Get temp images older than 7 days.
		$old_variants = $wpdb->get_results(
			$wpdb->prepare(
				"SELECT * FROM {$table_variants} 
				WHERE status = 'temp' 
				AND created_at < DATE_SUB(NOW(), INTERVAL %d DAY)",
				7
			),
			ARRAY_A
		);

		foreach ( $old_variants as $variant ) {
			// Delete file.
			if ( file_exists( $variant['temp_file_path'] ) ) {
				unlink( $variant['temp_file_path'] );
			}

			// Update status.
			$wpdb->update(
				$table_variants,
				array(
					'status'     => 'auto_deleted',
					'deleted_at' => current_time( 'mysql' ),
				),
				array( 'id' => $variant['id'] ),
				array( '%s', '%s' ),
				array( '%d' )
			);
		}
	}
}