<?php
/**
 * MetaForge Engine — Gutenberg Block Bridge
 *
 * Automatically registers a native WordPress block for any field group
 * that has `register_as_block` enabled in its settings.
 *
 * Usage in templates: the block renders as a <div> with data attributes
 * and a PHP render_callback that uses the existing MFE field API.
 *
 * To enable for a field group, set `register_as_block => 1` in its config.
 * Optionally set `block_title`, `block_category`, and `block_icon`.
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

class MetaForge_BlockBridge {

	public function __construct() {
		add_action( 'init', array( $this, 'register_blocks' ), 20 );
		add_action( 'enqueue_block_editor_assets', array( $this, 'enqueue_block_editor_assets' ) );
		// Modern Block Editor category registration (WP 5.8+)
		add_filter( 'block_categories_all', array( $this, 'register_block_category' ), 10, 2 );
	}

	/**
	 * Register MetaForge block category in Gutenberg inserter.
	 */
	public function register_block_category( $categories, $block_editor_context = null ) {
		if ( ! is_array( $categories ) ) {
			$categories = array();
		}
		foreach ( $categories as $cat ) {
			if ( isset( $cat['slug'] ) && $cat['slug'] === 'metaforge' ) {
				return $categories;
			}
		}
		array_unshift(
			$categories,
			array(
				'slug'  => 'metaforge',
				'title' => __( 'MetaForge', 'metaforge-engine' ),
				'icon'  => 'admin-generic',
			)
		);
		return $categories;
	}

	/**
	 * Enqueue block editor assets and localize blocks metadata.
	 */
	public function enqueue_block_editor_assets() {

		wp_enqueue_script(
			'metaforge-blocks-js',
			METAFORGE_URL . 'assets/js/blocks.js',
			array( 'wp-blocks', 'wp-element', 'wp-components', 'wp-block-editor' ),
			METAFORGE_VERSION,
			true
		);

		wp_add_inline_style(
			'wp-block-editor',
			'
            .mfe-block-card .mfe-canvas-fields-stack {
                display: flex !important;
                flex-direction: column !important;
                gap: 16px !important;
                width: 100% !important;
            }
            .mfe-block-card .mfe-canvas-field-row {
                width: 100% !important;
            }
            .mfe-block-card .components-base-control,
            .mfe-block-card .components-base-control__field,
            .mfe-block-card .components-text-control__input,
            .mfe-block-card .components-textarea-control__input,
            .mfe-block-card .components-select-control__input {
                width: 100% !important;
                max-width: 100% !important;
                box-sizing: border-box !important;
            }
            .mfe-block-card .components-base-control__label {
                font-weight: 600 !important;
                font-size: 12px !important;
                text-transform: uppercase !important;
                letter-spacing: 0.5px !important;
                color: #475569 !important;
                margin-bottom: 6px !important;
                display: block !important;
            }
            .mfe-block-card input.components-text-control__input,
            .mfe-block-card textarea.components-textarea-control__input {
                border: 1px solid #cbd5e1 !important;
                border-radius: 6px !important;
                padding: 8px 12px !important;
                font-size: 14px !important;
                width: 100% !important;
                box-sizing: border-box !important;
            }
            '
		);

		$posts = get_posts(
			array(
				'post_type'      => 'metaforge_group',
				'posts_per_page' => -1,
				'post_status'    => 'publish',
			)
		);

		$configs = array();
		foreach ( $posts as $post ) {
			$config = get_post_meta( $post->ID, '_metaforge_group_config', true );
			if ( is_array( $config ) ) {
				$configs[] = $config;
			}
		}

		global $metaforge_local_field_groups;
		if ( is_array( $metaforge_local_field_groups ) ) {
			foreach ( $metaforge_local_field_groups as $l_config ) {
				if ( is_array( $l_config ) ) {
					$configs[] = $l_config;
				}
			}
		}

		$blocks_data = array();
		foreach ( $configs as $config ) {
			if ( empty( $config['register_as_block'] ) ) {
				continue;
			}

			$raw_name   = ! empty( $config['group_name'] ) ? $config['group_name'] : ( ! empty( $config['block_title'] ) ? $config['block_title'] : 'Field Group' );
			$block_slug = ! empty( $config['block_slug'] ) ? sanitize_title( $config['block_slug'] ) : sanitize_title( $raw_name );
			if ( empty( $block_slug ) ) {
				$block_slug = 'block-' . ( ! empty( $config['group_key'] ) ? sanitize_title( $config['group_key'] ) : uniqid() );
			}

			$raw_cat   = ! empty( $config['block_category'] ) ? sanitize_text_field( $config['block_category'] ) : 'metaforge';
			$block_cat = ( $raw_cat === 'common' ) ? 'metaforge' : $raw_cat;

			$blocks_data[] = array(
				'slug'     => $block_slug,
				'title'    => ! empty( $config['block_title'] ) ? sanitize_text_field( $config['block_title'] ) : sanitize_text_field( $raw_name ),
				'icon'     => ! empty( $config['block_icon'] ) ? sanitize_text_field( $config['block_icon'] ) : 'admin-generic',
				'category' => $block_cat,
				'fields'   => $config['fields'] ?? array(),
			);
		}

		wp_localize_script( 'metaforge-blocks-js', 'metaforgeBlocksData', $blocks_data );
	}

	/**
	 * Iterate all metaforge_group CPTs and register blocks for
	 * any that have `register_as_block = 1` in their config.
	 */
	public function register_blocks() {
		if ( ! function_exists( 'register_block_type' ) ) {
			return;
		}

		wp_register_script(
			'metaforge-blocks-js',
			METAFORGE_URL . 'assets/js/blocks.js',
			array( 'wp-blocks', 'wp-element', 'wp-components', 'wp-block-editor', 'wp-editor', 'wp-data' ),
			METAFORGE_VERSION,
			true
		);

		$posts = get_posts(
			array(
				'post_type'      => 'metaforge_group',
				'posts_per_page' => -1,
				'post_status'    => 'publish',
			)
		);

		$configs = array();
		$ids     = array();
		foreach ( $posts as $post ) {
			$config = get_post_meta( $post->ID, '_metaforge_group_config', true );
			if ( is_array( $config ) ) {
				$configs[] = $config;
				$ids[]     = $post->ID;
			}
		}

		global $metaforge_local_field_groups;
		if ( is_array( $metaforge_local_field_groups ) ) {
			foreach ( $metaforge_local_field_groups as $l_config ) {
				if ( is_array( $l_config ) ) {
					$configs[] = $l_config;
					$ids[]     = 0;
				}
			}
		}

		foreach ( $configs as $i => $config ) {
			if ( empty( $config['register_as_block'] ) ) {
				continue;
			}

			$this->register_single_block( $config, $ids[ $i ] );
		}
	}

	/**
	 * Register one block type from a field group config.
	 */
	private function register_single_block( array $config, int $group_post_id ) {
		$raw_name   = ! empty( $config['group_name'] ) ? $config['group_name'] : ( ! empty( $config['block_title'] ) ? $config['block_title'] : 'Field Group' );
		$block_slug = ! empty( $config['block_slug'] ) ? sanitize_title( $config['block_slug'] ) : sanitize_title( $raw_name );

		if ( empty( $block_slug ) ) {
			$block_slug = 'block-' . ( $group_post_id > 0 ? $group_post_id : ( ! empty( $config['group_key'] ) ? sanitize_title( $config['group_key'] ) : uniqid() ) );
		}

		if ( empty( $block_slug ) ) {
			return;
		}

		$block_name = 'metaforge/' . $block_slug; // e.g. metaforge/hero-banner

		$title    = ! empty( $config['block_title'] ) ? sanitize_text_field( $config['block_title'] ) : sanitize_text_field( $raw_name );
		$icon     = ! empty( $config['block_icon'] ) ? sanitize_text_field( $config['block_icon'] ) : 'admin-generic';
		$raw_cat  = ! empty( $config['block_category'] ) ? sanitize_text_field( $config['block_category'] ) : 'metaforge';
		$category = ( $raw_cat === 'common' ) ? 'metaforge' : $raw_cat;

		// Build the block attributes schema from the field group's fields
		$attributes = $this->build_block_attributes( $config['fields'] ?? array() );

		register_block_type(
			$block_name,
			array(
				'api_version'     => 3,
				'title'           => $title,
				'icon'            => $icon,
				'category'        => in_array( $category, array( 'metaforge', 'text', 'media', 'design', 'widgets', 'common' ) )
										? $category : 'metaforge',
				'editor_script'   => 'metaforge-blocks-js',
				'attributes'      => $attributes,
				'render_callback' => function ( array $block_attrs, string $content ) use ( $config ) {
					return $this->render_block( $block_attrs, $config );
				},
				'supports'        => array(
					'align'           => array( 'wide', 'full' ),
					'anchor'          => true,
					'customClassName' => true,
					'jsx'             => true,
					'html'            => false,
				),
			)
		);
	}

	/**
	 * Build a Gutenberg attributes schema from MetaForge field definitions.
	 * Each field becomes a typed block attribute.
	 */
	private function build_block_attributes( array $fields ): array {
		$attrs = array();
		foreach ( $fields as $field ) {
			$name = $field['name'] ?? '';
			if ( ! $name ) {
				continue;
			}

			switch ( $field['type'] ?? 'text' ) {
				case 'true_false':
					$attrs[ $name ] = array(
						'type'    => 'boolean',
						'default' => false,
					);
					break;
				case 'number':
				case 'range':
					$attrs[ $name ] = array(
						'type'    => 'number',
						'default' => 0,
					);
					break;
				case 'image':
				case 'file':
					$attrs[ $name ] = array(
						'type'    => 'object',
						'default' => null,
					);
					break;
				case 'repeater':
				case 'group':
					$attrs[ $name ] = array(
						'type'    => 'array',
						'default' => array(),
					);
					break;
				case 'checkbox':
					$attrs[ $name ] = array(
						'type'    => 'array',
						'default' => array(),
					);
					break;
				case 'textarea':
				case 'wysiwyg':
					$attrs[ $name ] = array(
						'type'    => 'string',
						'default' => '',
					);
					break;
				default:
					$attrs[ $name ] = array(
						'type'    => 'string',
						'default' => '',
					);
			}
		}
		return $attrs;
	}

	/**
	 * Server-side render callback for a registered block.
	 *
	 * Priority: block editor attributes → post meta from the current post.
	 * This means blocks can display either inline editor values OR
	 * the saved post meta values when rendered on the frontend.
	 */
	private function render_block( array $block_attrs, array $config ): string {
		$fields = $config['fields'] ?? array();
		if ( empty( $fields ) ) {
			return '';
		}

		// Attempt to get the post ID from the current global context
		$post_id    = get_the_ID() ?: null;
		$block_slug = ! empty( $config['block_slug'] ) ? sanitize_title( $config['block_slug'] ) : ( ! empty( $config['group_name'] ) ? sanitize_title( $config['group_name'] ) : 'block' );

		// Prepare context variables for the template
		$block = array(
			'title'       => $config['block_title'] ?? $config['group_name'] ?? '',
			'description' => $config['block_description'] ?? '',
			'category'    => $config['block_category'] ?? 'common',
			'icon'        => $config['block_icon'] ?? 'admin-generic',
			'slug'        => $block_slug,
			'id'          => 'mfe-block-' . $block_slug . '-' . uniqid(),
			'align'       => $block_attrs['align'] ?? '',
			'className'   => $block_attrs['className'] ?? '',
		);

		// Format and gather all values into an array context so template can use them
		$context_fields = array();
		foreach ( $fields as $field ) {
			$name = $field['name'] ?? '';
			if ( ! $name ) {
				continue;
			}

			// Prefer block editor attributes; fallback to post meta
			$raw                     = $block_attrs[ $name ] ?? ( $post_id ? get_post_meta( $post_id, $name, true ) : '' );
			$context_fields[ $name ] = metaforge_format_value( $raw, $field );
		}

		// Search for template overrides in theme / child theme
		$template_slugs = array(
			"template-parts/blocks/block-{$block_slug}.php",
			"template-parts/blocks/{$block_slug}.php",
			"blocks/block-{$block_slug}.php",
			"blocks/{$block_slug}.php",
		);
		$template       = locate_template( $template_slugs );

		ob_start();
		if ( $template ) {
			// Include template in a clean function scope so variables don't bleed.
			// Expose $block and field values as variables.
			( static function ( $__template_path, $fields, $block ) {
				// Extract keys into variables (e.g. $hero_image, $title)
				if ( is_array( $fields ) ) {
					foreach ( $fields as $key => $val ) {
						if ( is_string( $key ) && preg_match( '/^[a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*$/', $key ) && $key !== '__template_path' && $key !== 'block' && $key !== 'fields' ) {
							$$key = $val;
						}
					}
				}
				include $__template_path;
			} )( $template, $context_fields, $block );
		} else {
			// Fallback render markup
			echo '<div class="mfe-block mfe-block--' . esc_attr( $block_slug ) . ' ' . esc_attr( $block['className'] ) . '" id="' . esc_attr( $block['id'] ) . '">';
			foreach ( $fields as $field ) {
				$name = $field['name'] ?? '';
				if ( ! $name ) {
					continue;
				}
				$this->render_block_field( $field, $context_fields[ $name ] );
			}
			echo '</div>';
		}
		return ob_get_clean();
	}

	/**
	 * Render a single field value in a block context.
	 * Produces clean, semantic HTML for each field type.
	 */
	private function render_block_field( array $field, $value ) {
		$type  = $field['type'] ?? 'text';
		$label = esc_html( $field['label'] ?? '' );
		$name  = esc_attr( $field['name'] ?? '' );

		echo '<div class="mfe-block__field mfe-block__field--' . esc_attr( $type ) . '" data-field="' . esc_attr( $name ) . '">';

		switch ( $type ) {
			case 'image':
				if ( is_array( $value ) && ! empty( $value['url'] ) ) {
					$alt = esc_attr( $value['alt'] ?? '' );
					echo '<img src="' . esc_url( $value['url'] ) . '" alt="' . esc_attr( $alt ) . '" class="mfe-block__image">';
				} elseif ( is_numeric( $value ) && $value > 0 ) {
					$src = wp_get_attachment_image_url( $value, 'full' );
					if ( $src ) {
						echo '<img src="' . esc_url( $src ) . '" alt="" class="mfe-block__image">';
					}
				} elseif ( is_string( $value ) && ! empty( $value ) ) {
					echo '<img src="' . esc_url( $value ) . '" alt="" class="mfe-block__image">';
				}
				break;

			case 'wysiwyg':
			case 'textarea':
				echo '<div class="mfe-block__text">' . wp_kses_post( $value ) . '</div>';
				break;

			case 'true_false':
				echo '<span class="mfe-block__bool">' . ( $value ? 'Yes' : 'No' ) . '</span>';
				break;

			case 'icon_picker':
				$icon = is_array( $value ) ? ( $value['icon'] ?? '' ) : (string) $value;
				if ( $icon ) {
					echo '<span class="dashicons ' . esc_attr( $icon ) . '"></span>';
				}
				break;

			case 'code_editor':
				echo '<pre class="mfe-block__code"><code>' . esc_html( (string) $value ) . '</code></pre>';
				break;

			case 'range':
				echo '<span class="mfe-block__range">' . esc_html( (string) $value ) . '</span>';
				break;

			case 'button':
				if ( is_array( $value ) && ! empty( $value['url'] ) ) {
					$btn_class = 'mfe-btn mfe-btn-' . esc_attr( $value['style'] ?? 'primary' );
					echo '<a href="' . esc_url( $value['url'] ) . '"';
					if ( ! empty( $value['target'] ) ) {
						echo ' target="' . esc_attr( $value['target'] ) . '"';
					}
					echo ' class="' . esc_attr( $btn_class ) . '">'
						. esc_html( $value['title'] ?: $value['url'] )
						. '</a>';
				}
				break;

			case 'link':
				if ( ! empty( $value['url'] ) ) {
					echo '<a href="' . esc_url( $value['url'] ) . '"';
					if ( ! empty( $value['target'] ) ) {
						echo ' target="' . esc_attr( $value['target'] ) . '"';
					}
					echo ' class="mfe-block__link">'
						. esc_html( $value['title'] ?: $value['url'] )
						. '</a>';
				}
				break;

			case 'repeater':
				if ( is_array( $value ) && ! empty( $value ) ) {
					echo '<div class="mfe-block__repeater">';
					foreach ( $value as $row_index => $row ) {
						echo '<div class="mfe-block__repeater-row" data-row="' . absint( $row_index ) . '">';
						if ( is_array( $row ) ) {
							foreach ( $row as $sub_name => $sub_val ) {
								echo '<span class="mfe-block__sub" data-key="' . esc_attr( $sub_name ) . '">'
									. esc_html( is_scalar( $sub_val ) ? $sub_val : wp_json_encode( $sub_val ) )
									. '</span>';
							}
						}
						echo '</div>';
					}
					echo '</div>';
				}
				break;

			default:
				echo '<span class="mfe-block__value">' . esc_html( is_scalar( $value ) ? $value : '' ) . '</span>';
		}

		echo '</div>';
	}
}