<?php

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

final class AIEO_Content_Forms {

	const SCHEMA = 'rooster-form@1';

	
	const KEYS = array( 'schema', 'key', 'title', 'from', 'notify', 'settings', 'fields' );

	
	public static function read( $path ) {
		$path  = (string) $path;
		$files = is_dir( $path ) ? (array) glob( trailingslashit( wp_normalize_path( $path ) ) . '*.form.json' ) : array( $path );
		sort( $files );
		$out = array();
		foreach ( $files as $file ) {
			if ( ! is_readable( (string) $file ) ) {
				return new WP_Error( 'aieo_form_file', sprintf( 'Cannot read %s.', $file ) );
			}
			$data = wp_json_file_decode( (string) $file, array( 'associative' => true ) );
			if ( ! is_array( $data ) ) {
				return new WP_Error( 'aieo_form_json', sprintf( '%s is not JSON.', $file ) );
			}
			$out[ (string) $file ] = $data;
		}
		if ( ! $out ) {
			return new WP_Error( 'aieo_form_none', sprintf( 'No *.form.json under %s.', $path ) );
		}
		return $out;
	}

	
	public static function validate( array $def ) {
		$errors   = array();
		$warnings = array();
		if ( self::SCHEMA !== (string) ( $def['schema'] ?? '' ) ) {
			$errors[] = 'schema: expected ' . self::SCHEMA . '.';
		}
		$key = (string) ( $def['key'] ?? '' );
		if ( '' === $key || sanitize_title( $key ) !== $key ) {
			$errors[] = 'key: a slug (lower case, digits, hyphens) is required.';
		}
		if ( '' === trim( (string) ( $def['title'] ?? '' ) ) ) {
			$errors[] = 'title: required.';
		}
		if ( isset( $def['from'] ) && ( ! class_exists( 'AIEO_Form_Premade' ) || ! AIEO_Form_Premade::get( (string) $def['from'] ) ) ) {
			$errors[] = 'from: no premade form ' . (string) $def['from'] . '.';
		}
		foreach ( array_diff( array_keys( $def ), self::KEYS ) as $extra ) {
			$warnings[] = 'unknown field ' . $extra . ' (ignored).';
		}
		if ( isset( $def['settings'] ) ) {
			foreach ( array_diff( array_keys( (array) $def['settings'] ), array_keys( AIEO_Form_CPT::setting_defaults() ) ) as $extra ) {
				$warnings[] = 'settings: unknown ' . $extra . ' (ignored).';
			}
		}
		$fields = $def['fields'] ?? null;
		if ( null === $fields && ! isset( $def['from'] ) ) {
			$errors[] = 'fields: required (or name a premade form in from).';
		}
		$seen = array();
		foreach ( (array) $fields as $i => $f ) {
			$at = 'fields[' . $i . ']';
			if ( ! is_array( $f ) || ! AIEO_Form_CPT::normalise_field( $f ) ) {
				$errors[] = $at . ': not a field (a key, a known type: ' . implode( ', ', array_keys( AIEO_Form_CPT::field_types() ) ) . '; choices for a choice field).';
				continue;
			}
			$k = sanitize_key( (string) $f['key'] );
			if ( isset( $seen[ $k ] ) ) {
				$errors[] = $at . ': the key ' . $k . ' is taken by an earlier field.';
			}
			$seen[ $k ] = true;
			foreach ( array_diff( array_keys( $f ), array_merge( array( 'key', 'type', 'label', 'required', 'choices', 'width' ), AIEO_Form_CPT::PROPS ) ) as $extra ) {
				$warnings[] = $at . ': unknown ' . $extra . ' (ignored).';
			}
			if ( isset( $f['width'] ) && ! in_array( (string) $f['width'], AIEO_Form_CPT::WIDTHS, true ) ) {
				$warnings[] = $at . ': width is full or half (full used).';
			}
		}
		return array( 'errors' => $errors, 'warnings' => $warnings );
	}

	
	public static function apply( array $def, $dry_run = false ) {
		$check  = self::validate( $def );
		$report = array( 'key' => (string) ( $def['key'] ?? '' ), 'action' => '', 'id' => 0, 'warnings' => $check['warnings'], 'errors' => $check['errors'] );
		if ( $check['errors'] ) {
			$report['action'] = 'refused';
			return $report;
		}
		$premade  = isset( $def['from'] ) ? AIEO_Form_Premade::get( (string) $def['from'] ) : null;
		$fields   = isset( $def['fields'] ) ? (array) $def['fields'] : (array) ( $premade['fields'] ?? array() );
		$settings = array_merge( (array) ( $premade['settings'] ?? array() ), (array) ( $def['settings'] ?? array() ) );
		$notify   = array_key_exists( 'notify', $def ) ? (bool) $def['notify'] : ( $premade ? ! empty( $premade['notify'] ) : null );
		$title    = sanitize_text_field( (string) $def['title'] );
		$id       = self::find( (string) $def['key'] );
		$report['id'] = $id;
		if ( $dry_run ) {
			$report['action'] = $id ? 'planned update' : 'planned create';
			return $report;
		}
		$created = false;
		if ( ! $id ) {
			$id = wp_insert_post(
				array(
					'post_type'   => AIEO_Form_CPT::POST_TYPE,
					'post_status' => 'publish',
					'post_title'  => $title,
					'post_name'   => (string) $def['key'],
				),
				true
			);
			if ( is_wp_error( $id ) ) {
				$report['action']   = 'refused';
				$report['errors'][] = $id->get_error_message();
				return $report;
			}
			$created = true;
		} elseif ( get_post_field( 'post_title', $id ) !== $title || 'publish' !== get_post_status( $id ) ) {
			wp_update_post( array( 'ID' => $id, 'post_title' => $title, 'post_status' => 'publish' ) );
			$created = null; 
		}
		$changed          = AIEO_Form_CPT::save_definition( (int) $id, $fields, $settings, $notify );
		$report['id']     = (int) $id;
		$report['action'] = true === $created ? 'created' : ( null === $created || $changed ? 'updated' : 'unchanged' );
		if ( class_exists( 'AIEO_Form_Render' ) ) {
			AIEO_Form_Render::reset();
		}
		return $report;
	}

	
	public static function find( $key ) {
		$ids = get_posts(
			array(
				'post_type'        => AIEO_Form_CPT::POST_TYPE,
				'name'             => sanitize_title( (string) $key ),
				'post_status'      => array( 'publish', 'draft', 'pending', 'private', 'future' ),
				'numberposts'      => 1,
				'fields'           => 'ids',
				'no_found_rows'    => true,
				'suppress_filters' => true,
			)
		);
		return $ids ? (int) $ids[0] : 0;
	}
}