<?php

declare(strict_types=1);

namespace Nih\CommandBuilder;

final class Child
{
    /**
     * @param resource $proc The process handle.
     */
    public function __construct(
        public readonly ?ChildStdin $stdin,
        public readonly ?ChildStdout $stdout,
        public readonly ?ChildStderr $stderr,
        public $proc,
    ) {
    }

    public function id(): int
    {
        if (!is_resource($this->proc)) {
            throw new ChildException('Resource was already closed');
        }

        $status = proc_get_status($this->proc);
        return $status['pid'];
    }

    public function waitWithOutput(): Output
    {
        if (!is_resource($this->proc)) {
            throw new ChildException('Resource was already closed');
        }

        // Avoid possible deadlock before waiting.
        $this->stdin?->close();

        $stdout = $this->stdout?->getContents();
        $stderr = $this->stderr?->getContents();
        $status = new ExitStatus(proc_close($this->proc));

        return new Output($stdout, $stderr, $status);
    }

    public function wait(): ExitStatus
    {
        if (!is_resource($this->proc)) {
            throw new ChildException('Resource was already closed');
        }

        // Avoid possible deadlock before waiting.
        $this->stdin?->close();

        return new ExitStatus(proc_close($this->proc));
    }

    public function kill(): bool
    {
        if (!is_resource($this->proc)) {
            throw new ChildException('Resource was already closed');
        }

        return proc_terminate($this->proc, 10);
    }

    public function __destruct()
    {
        if (is_resource($this->proc)) {
            proc_close($this->proc);
        }
    }
}