<?php

namespace DeliciousBrains\WPMDB\Common\MigrationState;

use DeliciousBrains\WPMDB\Common\Error\ErrorLog;
use DeliciousBrains\WPMDB\Common\Migration\MigrationHelper;
use DeliciousBrains\WPMDB\Common\MigrationPersistence\Persistence;
use DeliciousBrains\WPMDB\Common\Properties\DynamicProperties;
use DeliciousBrains\WPMDB\Common\Properties\Properties;
use DeliciousBrains\WPMDB\Common\Sanitize;
use DeliciousBrains\WPMDB\Common\Util\Util;
use DeliciousBrains\WPMDB\Common\Http\Http;
use DeliciousBrains\WPMDB\WPMDBDI;
use DI\DependencyException;
use DI\NotFoundException;
use WP_Error;

class MigrationStateManager {
	/**
	 * @var ErrorLog
	 */
	public $error_log;

	/**
	 * @var Properties
	 */
	public $props;

	/**
	 * @var Util
	 */
	public $util;

	/**
	 * @var StateDataContainer
	 */
	public $state_container;

	/**
	 * @var $state_data
	 */
	public $state_data;

	/**
	 * @var MigrationState
	 */
	public $migration_state;

	/**
	 * @var Http
	 */
	private $http;

	/**
	 * @var DynamicProperties
	 */
	private $dynamic_props;

	/**
	 * @var MigrationState
	 */
	private $migration_state_class;

	public function __construct(
		ErrorLog $error_log,
		Util $util,
		MigrationState $migration_state,
		Http $http,
		Properties $properties,
		StateDataContainer $state_data_container
	) {
		$this->error_log             = $error_log;
		$this->props                 = $properties;
		$this->util                  = $util;
		$this->state_container       = $state_data_container;
		$this->dynamic_props         = DynamicProperties::getInstance();
		$this->state_data            = $this->state_container->state_data;
		$this->migration_state_class = $migration_state;
		$this->http                  = $http;
	}

	public function get_state_data() {
		return $this->state_data;
	}

	/**
	 * Save the migration state, and replace the current item to be returned if there is an error.
	 *
	 * @param mixed       $state
	 * @param mixed       $default The default value to return on success, optional defaults to null.
	 * @param null|string $migration_id
	 *
	 * @return mixed|WP_Error
	 */
	public function save_migration_state( $state, $default = null, $migration_id = null ) {
		if ( ! $this->migration_state->set( $state, $migration_id ) ) {
			$error_msg = __( 'Failed to save migration state. Please contact support.', 'wp-migrate-db' );
			$this->error_log->log_error( $error_msg );

			return new WP_Error( 'wpmdb_error', $error_msg );
		}

		return $default;
	}

	public function get_state() {
		$migration_id = get_site_transient( WPMDB_MIGRATION_ID_TRANSIENT );

		if ( empty( $migration_id ) ) {
			return false;
		}

		return $this->migration_state->get( $migration_id );
	}

	/**
	 *  Restore previous migration state and merge in new information or initialize new migration state.
	 *
	 * @param null|string $id
	 *
	 * @return mixed|WP_Error
	 */
	public function get_migration_state( $id = null ) {
		$return = true;

		if ( ! empty( $id ) ) {
			$this->migration_state = new MigrationState( $id );
			$state                 = $this->migration_state->get();
			if ( empty( $state ) || $this->migration_state->id() !== $id ) {
				$error_msg = __( 'Failed to retrieve migration state. Please contact support.', 'wp-migrate-db' );
				$this->error_log->log_error( $error_msg );

				return new WP_Error( 'wpmdb_error', $error_msg );
			} else {
				$this->state_data = array_merge( $state, $this->state_data );

				$return = $this->save_migration_state( $this->state_data, true );
			}
		} else {
			$this->migration_state = new MigrationState();
		}

		return $return;
	}

	/**
	 * Sets $this->state_data from $_POST, potentially un-slashed and un-sanitized.
	 *
	 * @param array  $key_rules An optional associative array of expected keys and their sanitization rule(s).
	 * @param string $state_key The key in $_POST that contains the migration state id (defaults to 'migration_state_id').
	 * @param string $context   The method that is specifying the sanitization rules. Defaults to calling method.
	 *
	 * @return mixed|WP_Error
	 * @throws DependencyException
	 * @throws NotFoundException
	 */
	public function set_post_data( $key_rules = [], $state_key = 'migration_state_id', $context = '' ) {
		if ( empty( $key_rules ) ) {
			return Persistence::getStateData();
		}

		if ( defined( 'DOING_WPMDB_TESTS' ) ) {
			// @TODO this is a major hack and should be refactored
			$this->state_data = $_POST;
		} elseif ( empty( $this->state_data ) ) {
			$this->state_data = Util::safe_wp_unslash( $_POST );
		} else {
			return $this->state_data;
		}

		// From this point on we're handling data originating from $_POST, so original $key_rules apply.
		$context   = empty( $context ) ? $this->util->get_caller_function() : trim( $context );
		$sanitized = Sanitize::sanitize_data( $this->state_data, $key_rules, $context );

		if ( is_wp_error( $sanitized ) ) {
			$this->error_log->log_error( $sanitized->get_error_message() );
			error_log( $sanitized->get_error_message() );

			return $sanitized;
		}

		$this->state_data = $sanitized;

		if ( false === $this->state_data ) {
			exit;
		}

		// Always pass migration_state_id or $state_key with every AJAX request.
		if ( ! MigrationHelper::is_remote() ) {
			$migration_state_id = null;
			if ( ! empty( $this->state_data[ $state_key ] ) ) {
				$migration_state_id = $this->state_data[ $state_key ];
			}

			$result = $this->get_migration_state( $migration_state_id );

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

		WPMDBDI::getInstance()->get( StateDataContainer::class )->setData( $this->state_data );

		return $this->state_data;
	}
}