<?php
namespace Akram;

defined( 'ABSPATH' ) || exit;

/**
 * Storage for builder documents and their pre-rendered output.
 *
 * _akram_mode   'builder' when the post is built with Akram
 * _akram_data   editor document (JSON)
 * _akram_out    rendered output + runtime metadata (JSON)
 * _akram_css    compiled CSS
 * _akram_draft  unpublished draft {doc, out, css, time, user}
 */
final class Document {

	const MAX_REVISIONS = 30;

	public static function is_built( $post_id ) {
		return 'builder' === get_post_meta( $post_id, '_akram_mode', true );
	}

	public static function get_doc( $post_id, $draft = false ) {
		if ( $draft ) {
			$d = self::get_draft( $post_id );
			if ( $d && isset( $d['doc'] ) ) {
				return $d['doc'];
			}
		}
		$raw = get_post_meta( $post_id, '_akram_data', true );
		$doc = is_string( $raw ) && '' !== $raw ? json_decode( $raw, true ) : null;
		return is_array( $doc ) ? $doc : null;
	}

	public static function get_out( $post_id, $draft = false ) {
		if ( $draft ) {
			$d = self::get_draft( $post_id );
			if ( $d && isset( $d['out'] ) ) {
				$d['out']['css'] = $d['css'] ?? '';
				$d['out']['draft'] = true;
				return $d['out'];
			}
		}
		$raw = get_post_meta( $post_id, '_akram_out', true );
		$out = is_string( $raw ) && '' !== $raw ? json_decode( $raw, true ) : null;
		return is_array( $out ) ? $out : null;
	}

	public static function get_draft( $post_id ) {
		$raw = get_post_meta( $post_id, '_akram_draft', true );
		$d   = is_string( $raw ) && '' !== $raw ? json_decode( $raw, true ) : null;
		return is_array( $d ) ? $d : null;
	}

	public static function hash( $post_id ) {
		return md5( (string) get_post_meta( $post_id, '_akram_data', true ) . '|' . (string) get_post_meta( $post_id, '_akram_draft', true ) );
	}

	/**
	 * Clean incoming render output from the editor.
	 */
	/** Rendered output from the editor. $css_fonts: font families the server-built stylesheet uses. */
	public static function clean_out( array $out, array $css_fonts = array() ) {
		$clean = array(
			'html'    => Sanitize::html( (string) ( $out['html'] ?? '' ) ),
			'modules' => array_values( array_filter( array_map( 'sanitize_key', (array) ( $out['modules'] ?? array() ) ) ) ),
			'types'   => array_values( array_filter( array_map( 'sanitize_key', (array) ( $out['types'] ?? array() ) ) ) ),
			'dyn'     => is_array( $out['dyn'] ?? null ) ? $out['dyn'] : array(),
			'cond'    => is_array( $out['cond'] ?? null ) ? $out['cond'] : array(),
			'forms'   => is_array( $out['forms'] ?? null ) ? $out['forms'] : array(),
			'lock'    => self::clean_locks( (array) ( $out['lock'] ?? array() ) ),
			'flags'   => array_map( 'sanitize_key', array_filter( (array) ( $out['flags'] ?? array() ), 'is_scalar' ) ),
			'tpl'     => array_values( array_filter( array_map( 'absint', (array) ( $out['tpl'] ?? array() ) ) ) ),
			'fonts'   => self::clean_fonts( (array) ( $out['fonts'] ?? array() ), $css_fonts ),
			'anim'    => ! empty( $out['anim'] ),
			'engine'  => AKRAM_VERSION,
			'time'    => time(),
		);
		return $clean;
	}

	/** Font families to load (family => weights), merged from several lists and reduced to safe names. */
	public static function clean_fonts( array ...$lists ) {
		$clean = array();
		foreach ( $lists as $list ) {
			foreach ( $list as $family => $weights ) {
				$family = trim( preg_replace( '/[^A-Za-z0-9 \-]/', '', (string) $family ) );
				if ( '' === $family ) {
					continue;
				}
				foreach ( (array) $weights as $w ) {
					$w = preg_replace( '/[^0-9]/', '', (string) $w );
					if ( '' !== $w ) {
						$clean[ $family ][ $w ] = $w;
					}
				}
				$clean[ $family ] = $clean[ $family ] ?? array();
			}
		}
		foreach ( $clean as $family => $weights ) {
			sort( $weights, SORT_STRING );
			$clean[ $family ] = array_values( $weights );
		}
		return $clean;
	}

	/** Protected-content rules: passwords are stored as a keyed hash, never in clear text. */
	private static function clean_locks( array $locks ) {
		$clean = array();
		foreach ( $locks as $id => $l ) {
			$id = sanitize_key( (string) $id );
			if ( ! $id || ! is_array( $l ) ) {
				continue;
			}
			$mode = in_array( $l['mode'] ?? '', array( 'password', 'login', 'role' ), true ) ? $l['mode'] : 'password';
			$pass = (string) ( $l['pass'] ?? '' );
			$clean[ $id ] = array(
				'mode'  => $mode,
				'pass'  => '' === $pass ? '' : ( 0 === strpos( $pass, 'nxh$' ) ? $pass : Runtime::pass_hash( $pass ) ),
				'roles' => sanitize_text_field( (string) ( $l['roles'] ?? '' ) ),
			);
		}
		return $clean;
	}

	/**
	 * Save a document. $mode: 'publish' writes the live version, 'draft' only stores a draft.
	 * The stylesheet is built here from the document's design settings (Css::document); no CSS is accepted.
	 */
	public static function save( $post_id, array $doc, array $out, $mode = 'publish' ) {
		$doc = Sanitize::document( $doc );
		if ( null === $doc ) {
			return new \WP_Error( 'akram_invalid', __( 'The document structure is invalid.', 'akram' ), array( 'status' => 400 ) );
		}
		$compiled = Css::document( $doc );
		$css      = $compiled['css'];
		$out      = self::clean_out( $out, $compiled['fonts'] );
		// Documents rendered before the post existed (page kits, imports) carry form ID 0.
		$out['html'] = str_replace( 'data-nx-form="0:', 'data-nx-form="' . (int) $post_id . ':', $out['html'] );
		Conditions::note_rules( $out['cond'] );

		if ( 'draft' === $mode ) {
			update_post_meta(
				$post_id,
				'_akram_draft',
				wp_slash(
					wp_json_encode(
						array(
							'doc'  => $doc,
							'out'  => $out,
							'css'  => $css,
							'time' => time(),
							'user' => get_current_user_id(),
						)
					)
				)
			);
			update_post_meta( $post_id, '_akram_mode', 'builder' );
			return true;
		}

		self::store_revision( $post_id );
		update_post_meta( $post_id, '_akram_mode', 'builder' );
		// A page migrated from Elementor: stop Elementor from rendering it and loading its assets.
		// The Elementor data stays untouched; the flag is kept so the switch can be undone.
		if ( 'builder' === get_post_meta( $post_id, '_elementor_edit_mode', true ) ) {
			update_post_meta( $post_id, '_akram_elementor_edit_mode', 'builder' );
			delete_post_meta( $post_id, '_elementor_edit_mode' );
			if ( 'elementor_header_footer' === get_post_meta( $post_id, '_wp_page_template', true ) || 'elementor_canvas' === get_post_meta( $post_id, '_wp_page_template', true ) ) {
				update_post_meta( $post_id, '_wp_page_template', 'elementor_canvas' === get_post_meta( $post_id, '_wp_page_template', true ) ? 'akram-canvas' : 'akram-full' );
			}
		}
		update_post_meta( $post_id, '_akram_data', wp_slash( wp_json_encode( $doc ) ) );
		update_post_meta( $post_id, '_akram_out', wp_slash( wp_json_encode( $out ) ) );
		update_post_meta( $post_id, '_akram_css', wp_slash( $css ) );
		delete_post_meta( $post_id, '_akram_draft' );
		self::write_css( $post_id, $css );
		self::write_fallback( $post_id, $out );
		Frontend::flush_caches( $post_id );
		do_action( 'akram_document_saved', $post_id, $doc, $out );
		return true;
	}

	/**
	 * Plain-HTML copy in post_content: survives plugin deactivation, readable by SEO plugins & search.
	 * It holds markup only; styles are always loaded with wp_enqueue_style() / wp_add_inline_style().
	 */
	private static function write_fallback( $post_id, array $out ) {
		$post = get_post( $post_id );
		if ( ! $post || 'akram_template' === $post->post_type ) {
			return;
		}
		$html    = preg_replace( '/<!--nx:lock ([a-z0-9_-]+)-->[\s\S]*?<!--nx:else \1-->/i', '', $out['html'] );
		$html    = preg_replace( '/<!--\/?nx:[^>]*-->/', '', $html );
		$html    = preg_replace( '/\{\{nx:[A-Za-z0-9+\/=]+\}\}/', '', $html );
		$content = '<!-- akram:fallback -->' . $html;
		remove_action( 'post_updated', 'wp_save_post_revision' );
		$GLOBALS['akram_saving_fallback'] = true;
		wp_update_post(
			array(
				'ID'           => $post_id,
				'post_content' => $content,
			)
		);
		$GLOBALS['akram_saving_fallback'] = false;
		add_action( 'post_updated', 'wp_save_post_revision' );
	}

	private static function store_revision( $post_id ) {
		$current = get_post_meta( $post_id, '_akram_data', true );
		if ( ! $current ) {
			return;
		}
		wp_insert_post(
			array(
				'post_type'    => 'akram_revision',
				'post_parent'  => $post_id,
				'post_status'  => 'publish',
				'post_title'   => get_the_title( $post_id ),
				'post_content' => wp_slash( $current ),
				'post_author'  => get_current_user_id(),
			)
		);
		$old = get_posts(
			array(
				'post_type'      => 'akram_revision',
				'post_parent'    => $post_id,
				'posts_per_page' => -1,
				'fields'         => 'ids',
				'orderby'        => 'ID',
				'order'          => 'DESC',
				'offset'         => self::MAX_REVISIONS,
			)
		);
		foreach ( $old as $id ) {
			wp_delete_post( $id, true );
		}
	}

	public static function revisions( $post_id ) {
		$out = array();
		foreach ( get_posts(
			array(
				'post_type'      => 'akram_revision',
				'post_parent'    => $post_id,
				'posts_per_page' => self::MAX_REVISIONS,
				'orderby'        => 'ID',
				'order'          => 'DESC',
			)
		) as $rev ) {
			$user  = get_userdata( (int) $rev->post_author );
			$out[] = array(
				'id'     => $rev->ID,
				'date'   => get_post_time( 'c', true, $rev ),
				'author' => $user ? $user->display_name : '',
				'avatar' => $user ? get_avatar_url( $user->ID, array( 'size' => 48 ) ) : '',
				'size'   => strlen( $rev->post_content ),
			);
		}
		return $out;
	}

	public static function revision_doc( $rev_id, $post_id ) {
		$rev = get_post( $rev_id );
		if ( ! $rev || 'akram_revision' !== $rev->post_type || (int) $rev->post_parent !== (int) $post_id ) {
			return null;
		}
		$doc = json_decode( $rev->post_content, true );
		return is_array( $doc ) ? $doc : null;
	}

	// ---------------------------------------------------------------------
	// CSS files
	// ---------------------------------------------------------------------
	public static function upload_dir() {
		$u = wp_upload_dir( null, false );
		return array(
			'dir' => trailingslashit( $u['basedir'] ) . 'akram/',
			'url' => set_url_scheme( trailingslashit( $u['baseurl'] ) . 'akram/' ),
		);
	}

	public static function ensure_upload_dir() {
		$d = self::upload_dir();
		foreach ( array( '', 'css', 'fonts' ) as $sub ) {
			if ( ! is_dir( $d['dir'] . $sub ) ) {
				wp_mkdir_p( $d['dir'] . $sub );
			}
		}
		if ( ! file_exists( $d['dir'] . 'index.php' ) ) {
			@file_put_contents( $d['dir'] . 'index.php', "<?php\n// Silence is golden.\n" );
		}
		return wp_is_writable( $d['dir'] );
	}

	public static function write_css( $post_id, $css ) {
		if ( 'file' !== Options::get( 'css_method' ) || ! self::ensure_upload_dir() ) {
			delete_post_meta( $post_id, '_akram_css_file' );
			return false;
		}
		$d    = self::upload_dir();
		$file = 'css/post-' . (int) $post_id . '.css';
		$ok   = false !== @file_put_contents( $d['dir'] . $file, $css );
		if ( $ok ) {
			update_post_meta( $post_id, '_akram_css_file', substr( md5( $css ), 0, 10 ) );
		} else {
			delete_post_meta( $post_id, '_akram_css_file' );
		}
		return $ok;
	}

	/** URL of the compiled CSS file or null (=> print inline). */
	public static function css_url( $post_id ) {
		$v = get_post_meta( $post_id, '_akram_css_file', true );
		if ( ! $v || 'file' !== Options::get( 'css_method' ) ) {
			return null;
		}
		$d = self::upload_dir();
		if ( ! file_exists( $d['dir'] . 'css/post-' . (int) $post_id . '.css' ) ) {
			return null;
		}
		return $d['url'] . 'css/post-' . (int) $post_id . '.css?v=' . $v;
	}

	public static function css( $post_id ) {
		return (string) get_post_meta( $post_id, '_akram_css', true );
	}

	// ---------------------------------------------------------------------
	// Global design system CSS
	// ---------------------------------------------------------------------
	public static function global_css() {
		$css = get_option( 'akram_global_css', '' );
		if ( '' === $css ) {
			$file = AKRAM_DIR . 'assets/build/' . Plugin::build_file( 'global-default.css' );
			$css  = file_exists( $file ) ? (string) file_get_contents( $file ) : '';
		}
		return $css;
	}

	/** Save the design system. Its stylesheet is built here from the settings (Css::globals). */
	public static function save_globals( array $globals ) {
		$compiled = Css::globals( $globals );
		$css      = $compiled['css'];
		update_option( 'akram_globals', $globals, true );
		update_option( 'akram_global_css', $css, true );
		update_option( 'akram_global_fonts', self::clean_fonts( $compiled['fonts'] ), true );
		update_option( 'akram_global_ver', substr( md5( $css . microtime() ), 0, 10 ), true );
		if ( 'file' === Options::get( 'css_method' ) && self::ensure_upload_dir() ) {
			$d = self::upload_dir();
			@file_put_contents( $d['dir'] . 'css/global.css', $css );
		}
		Frontend::flush_caches();
	}

	/** Rebuild a saved document's stylesheet from its stored design data. */
	public static function rebuild_css( $post_id ) {
		$doc = self::get_doc( $post_id );
		if ( ! $doc ) {
			return false;
		}
		$css = Css::document( $doc )['css'];
		update_post_meta( $post_id, '_akram_css', wp_slash( $css ) );
		self::write_css( $post_id, $css );
		return true;
	}

	/** Rebuild every stylesheet (after the breakpoints or the CSS storage method change). Returns the count. */
	public static function rebuild_all_css( $limit = 5000 ) {
		$n = 0;
		foreach ( self::all_built( absint( $limit ) ? absint( $limit ) : 5000 ) as $id ) {
			$n += self::rebuild_css( $id ) ? 1 : 0;
		}
		self::save_globals( Options::globals() );
		return $n;
	}

	public static function global_css_url() {
		$d   = self::upload_dir();
		$ver = get_option( 'akram_global_ver', '' );
		if ( 'file' === Options::get( 'css_method' ) && $ver && file_exists( $d['dir'] . 'css/global.css' ) ) {
			return $d['url'] . 'css/global.css?v=' . $ver;
		}
		if ( ! get_option( 'akram_global_css' ) && file_exists( AKRAM_DIR . 'assets/build/global-default.css' ) ) {
			return Plugin::build_url( 'global-default.css' ) . '?v=' . AKRAM_VERSION;
		}
		return null;
	}

	/** All posts built with Akram (for rebuild tools). */
	public static function all_built( $limit = 500 ) {
		return get_posts(
			array(
				'post_type'      => array_values( array_unique( array_merge( array_values( get_post_types( array( 'public' => true ) ) ), array( 'akram_template' ) ) ) ),
				'post_status'    => array( 'publish', 'draft', 'private', 'pending', 'future' ),
				'meta_key'       => '_akram_mode', // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key -- bounded query on a builder meta key.
				'meta_value'     => 'builder', // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_value -- bounded query on a builder meta key.
				'posts_per_page' => $limit,
				'fields'         => 'ids',
			)
		);
	}
}