<?php

/**
 * In-memory wrapper around a local workflow queue job.
 *
 * Runtime step snapshots live in context_json under `_execution`.
 * Step logs live in execution_json (same shape as remote callback logs).
 *
 * @package AfroIT_Messaging_WorkflowAutomations
 */

namespace AfroIT\Messaging\WorkflowAutomations\ExecutionEngine;

use AfroIT\Messaging\WorkflowAutomations\Workflows\WorkflowJob;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Class Execution
 */
final class Execution {

	public const CONTEXT_KEY = '_execution';

	/**
	 * @var WorkflowJob
	 */
	private WorkflowJob $job;

	/**
	 * @var array<string, mixed>
	 */
	private array $context;

	/**
	 * @var array<int, array<string, mixed>>
	 */
	private array $logs;

	/**
	 * @param WorkflowJob $job Queue job.
	 */
	public function __construct( WorkflowJob $job ) {
		$this->job     = $job;
		$this->context = $job->getContext();
		$this->logs    = $this->normalize_logs( $job->getExecutionResults() );
	}

	/**
	 * @return WorkflowJob
	 */
	public function job(): WorkflowJob {
		return $this->job;
	}

	/**
	 * @return int
	 */
	public function id(): int {
		return $this->job->id;
	}

	/**
	 * @return string
	 */
	public function status(): string {
		return $this->job->status;
	}

	/**
	 * @param string $status Status.
	 * @return void
	 */
	public function set_status( string $status ): void {
		$this->job->status = $status;
	}

	/**
	 * @return array<string, mixed>
	 */
	public function context(): array {
		$public = $this->context;
		unset( $public[ self::CONTEXT_KEY ] );
		return $public;
	}

	/**
	 * Replace public context while preserving runtime state.
	 *
	 * @param array<string, mixed> $context Context.
	 * @return void
	 */
	public function set_context( array $context ): void {
		$runtime = $this->runtime_state();
		unset( $context[ self::CONTEXT_KEY ] );
		$this->context                    = $context;
		$this->context[ self::CONTEXT_KEY ] = $runtime;
	}

	/**
	 * @return int
	 */
	public function current_step_index(): int {
		return (int) ( $this->runtime_state()['current_step_index'] ?? 0 );
	}

	/**
	 * @param int $index Step index.
	 * @return void
	 */
	public function set_current_step_index( int $index ): void {
		$state                         = $this->runtime_state();
		$state['current_step_index']   = max( 0, $index );
		$this->write_runtime_state( $state );
	}

	/**
	 * @return array<int, array<string, mixed>>
	 */
	public function get_steps(): array {
		$state = $this->runtime_state();
		if ( isset( $state['runtime_steps'] ) && is_array( $state['runtime_steps'] ) ) {
			return $state['runtime_steps'];
		}
		if ( isset( $state['initial_runtime_steps'] ) && is_array( $state['initial_runtime_steps'] ) ) {
			return $state['initial_runtime_steps'];
		}

		return array();
	}

	/**
	 * @param array<int, array<string, mixed>>|null $steps Runtime steps, or null to clear.
	 * @return void
	 */
	public function set_runtime_steps( ?array $steps ): void {
		$state = $this->runtime_state();
		if ( null === $steps ) {
			unset( $state['runtime_steps'] );
		} else {
			$state['runtime_steps'] = array_values( $steps );
		}
		$this->write_runtime_state( $state );
	}

	/**
	 * Seed initial steps when creating a new execution.
	 *
	 * @param array<int, array<string, mixed>> $steps Steps.
	 * @return void
	 */
	public function set_initial_steps( array $steps ): void {
		$state                            = $this->runtime_state();
		$state['initial_runtime_steps']   = array_values( $steps );
		$state['current_step_index']      = $state['current_step_index'] ?? 0;
		$this->write_runtime_state( $state );
	}

	/**
	 * @return string|null
	 */
	public function next_run_at(): ?string {
		$run_at = trim( (string) $this->job->run_at );
		return '' !== $run_at ? $run_at : null;
	}

	/**
	 * @param string|null $run_at MySQL datetime or null.
	 * @return void
	 */
	public function set_next_run_at( ?string $run_at ): void {
		$this->job->run_at = $run_at ?? current_time( 'mysql' );
	}

	/**
	 * @return string|null
	 */
	public function error_message(): ?string {
		$message = $this->runtime_state()['error_message'] ?? null;
		return is_string( $message ) && '' !== $message ? $message : null;
	}

	/**
	 * @param string|null $message Error message.
	 * @return void
	 */
	public function set_error_message( ?string $message ): void {
		$state = $this->runtime_state();
		if ( null === $message || '' === $message ) {
			unset( $state['error_message'] );
		} else {
			$state['error_message'] = $message;
		}
		$this->write_runtime_state( $state );
	}

	/**
	 * Mark a terminal status and clear runtime resume data.
	 *
	 * @param string      $status  Status.
	 * @param string|null $message Optional error/stop message.
	 * @return void
	 */
	public function set_terminal_state( string $status, ?string $message = null ): void {
		$this->set_status( $status );
		$this->set_next_run_at( current_time( 'mysql' ) );
		$this->set_runtime_steps( null );
		$state                  = $this->runtime_state();
		$state['completed_at']  = current_time( 'mysql' );
		if ( null !== $message && '' !== $message ) {
			$state['error_message'] = $message;
		}
		$this->write_runtime_state( $state );
	}

	/**
	 * Append a step log entry.
	 *
	 * @param int                  $step_index Step index.
	 * @param string               $step_type  Step type.
	 * @param string               $status     Status.
	 * @param string               $message    Message.
	 * @param array<string, mixed> $details    Details.
	 * @return void
	 */
	public function append_log( int $step_index, string $step_type, string $status, string $message, array $details = array() ): void {
		$this->logs[] = array(
			'step_index'  => $step_index,
			'type'        => $step_type,
			'status'      => $status,
			'message'     => $message,
			'executed_at' => current_time( 'mysql' ),
			'details'     => $details,
		);
	}

	/**
	 * @return array<int, array<string, mixed>>
	 */
	public function logs(): array {
		return $this->logs;
	}

	/**
	 * Context JSON including runtime state (for persistence).
	 *
	 * @return array<string, mixed>
	 */
	public function context_for_storage(): array {
		return $this->context;
	}

	/**
	 * @return array<string, mixed>
	 */
	private function runtime_state(): array {
		$state = $this->context[ self::CONTEXT_KEY ] ?? array();
		return is_array( $state ) ? $state : array();
	}

	/**
	 * @param array<string, mixed> $state Runtime state.
	 * @return void
	 */
	private function write_runtime_state( array $state ): void {
		$this->context[ self::CONTEXT_KEY ] = $state;
	}

	/**
	 * @param array<int|string, mixed> $logs Raw logs.
	 * @return array<int, array<string, mixed>>
	 */
	private function normalize_logs( array $logs ): array {
		$out = array();
		foreach ( $logs as $entry ) {
			if ( is_array( $entry ) ) {
				$out[] = $entry;
			}
		}

		return $out;
	}
}