<?php
/**
 * Storage of forms (F-FORMS-01).
 *
 * @package ForensixDigital
 */

declare(strict_types=1);

// phpcs:disable WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Our own tables; entries are read right after being written.

namespace ForensixDigital\Apps\Forms;

use ForensixDigital\Core\Schema;

/**
 * Forms and entries live in the app's own tables, created when the app is turned on and dropped
 * only when its data is deleted.
 */
final class FormStore {

	public const FORMS   = 'forensix_forms';
	public const ENTRIES = 'forensix_entries';

	public const MAIL_NONE   = 'none';
	public const MAIL_SENT   = 'sent';
	public const MAIL_FAILED = 'failed';

	/**
	 * Creates or updates the tables.
	 */
	public static function install(): void {
		global $wpdb;
		require_once ABSPATH . 'wp-admin/includes/upgrade.php';
		$charset = $wpdb->get_charset_collate();
		$forms   = Schema::table( self::FORMS );
		$entries = Schema::table( self::ENTRIES );

		dbDelta(
			"CREATE TABLE {$forms} (
id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
title varchar(200) NOT NULL,
definition longtext NOT NULL,
created_at datetime NOT NULL,
updated_at datetime NOT NULL,
PRIMARY KEY  (id)
) {$charset};"
		);
		dbDelta(
			"CREATE TABLE {$entries} (
id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
form_id bigint(20) unsigned NOT NULL,
data longtext NOT NULL,
is_read tinyint(1) unsigned NOT NULL DEFAULT 0,
mail_status varchar(10) NOT NULL DEFAULT 'none',
mail_error text NULL,
email varchar(190) NOT NULL DEFAULT '',
created_at datetime NOT NULL,
PRIMARY KEY  (id),
KEY form_created (form_id,created_at),
KEY email (email),
KEY mail_status (mail_status)
) {$charset};"
		);
	}

	/**
	 * Drops both tables.
	 */
	public static function drop(): void {
		global $wpdb;
		foreach ( array( self::ENTRIES, self::FORMS ) as $name ) {
			// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.DirectDatabaseQuery.SchemaChange -- The app removes its own tables.
			$wpdb->query( $wpdb->prepare( 'DROP TABLE IF EXISTS %i', Schema::table( $name ) ) );
		}
	}

	/**
	 * Saves a new form.
	 *
	 * @param string         $title      Title.
	 * @param FormDefinition $definition Definition.
	 * @return int Form id.
	 */
	public function create( string $title, FormDefinition $definition ): int {
		global $wpdb;
		$now = current_time( 'mysql', true );
		$wpdb->insert(
			Schema::table( self::FORMS ),
			array(
				'title'      => mb_substr( $title, 0, 200 ),
				'definition' => (string) wp_json_encode( $definition->to_array() ),
				'created_at' => $now,
				'updated_at' => $now,
			)
		);
		return (int) $wpdb->insert_id;
	}

	/**
	 * Changes a form.
	 *
	 * @param int            $id         Form id.
	 * @param string         $title      Title.
	 * @param FormDefinition $definition Definition.
	 */
	public function update( int $id, string $title, FormDefinition $definition ): bool {
		global $wpdb;
		return false !== $wpdb->update(
			Schema::table( self::FORMS ),
			array(
				'title'      => mb_substr( $title, 0, 200 ),
				'definition' => (string) wp_json_encode( $definition->to_array() ),
				'updated_at' => current_time( 'mysql', true ),
			),
			array( 'id' => $id )
		);
	}

	/**
	 * Deletes a form and its entries.
	 *
	 * @param int $id Form id.
	 */
	public function delete( int $id ): void {
		global $wpdb;
		$entries = $wpdb->get_col( $wpdb->prepare( 'SELECT id FROM %i WHERE form_id = %d', Schema::table( self::ENTRIES ), $id ) );
		$wpdb->delete( Schema::table( self::ENTRIES ), array( 'form_id' => $id ) );
		$wpdb->delete( Schema::table( self::FORMS ), array( 'id' => $id ) );
		foreach ( is_array( $entries ) ? $entries : array() as $entry ) {
			/** This action is documented in EntryStore::delete(). */
			do_action( 'forensix_form_entry_deleted', (int) $entry );
		}
	}

	/**
	 * One form.
	 *
	 * @param int $id Form id.
	 * @return array{id: int, title: string, definition: FormDefinition}|null
	 */
	public function find( int $id ): ?array {
		global $wpdb;
		$row = $wpdb->get_row( $wpdb->prepare( 'SELECT * FROM %i WHERE id = %d', Schema::table( self::FORMS ), $id ), ARRAY_A );
		return is_array( $row ) ? self::row( $row ) : null;
	}

	/**
	 * All forms, newest first.
	 *
	 * @return array<int, array{id: int, title: string, definition: FormDefinition}>
	 */
	public function all(): array {
		global $wpdb;
		$rows = $wpdb->get_results( $wpdb->prepare( 'SELECT * FROM %i ORDER BY id DESC', Schema::table( self::FORMS ) ), ARRAY_A );
		return array_map( array( self::class, 'row' ), is_array( $rows ) ? $rows : array() );
	}

	/**
	 * Builds the result of a row.
	 *
	 * @param array $row Table row.
	 * @phpstan-param array<string, mixed> $row
	 * @return array{id: int, title: string, definition: FormDefinition}
	 */
	private static function row( array $row ): array {
		$data = json_decode( (string) $row['definition'], true );
		return array(
			'id'         => (int) $row['id'],
			'title'      => (string) $row['title'],
			'definition' => new FormDefinition( is_array( $data ) ? $data : array() ),
		);
	}
}