<?php

namespace NoccyLabs\React\Protocol\Line;

use Closure;
use NoccyLabs\React\Protocol\ProtocolInterface;

class LineProtocol implements ProtocolInterface
{
    public function __construct(
        private readonly string $lineBreak = "\n",
        private readonly bool $quoteStrings = false,
        private readonly bool $escapeSpecial = false,
        private readonly ?Closure $beforePackCb = null,
        private readonly ?Closure $afterPackCb = null,
        private readonly ?Closure $beforeUnpackCb = null,
        private readonly ?Closure $afterUnpackCb = null,
    )
    {
        
    }

    public function packFrame(array $frame): string
    {
        if (is_callable($this->beforePackCb))
            $frame = call_user_func($this->beforePackCb, $frame);

        if ($this->escapeSpecial) {
            $frame = array_map(quotemeta(...), $frame);
        }

        if ($this->quoteStrings) {
            $frame = array_map(fn($v) => is_string($v) ? ('"'.str_replace('"',"\\\"",$v).'"') : $v, $frame);
        }
        
        $data = join(" ", $frame);
        $data .= $this->lineBreak;

        if (is_callable($this->afterPackCb))
            $data = call_user_func($this->afterPackCb, $data);

        return $data;
    }

    public function unpackFrame(string $data): array
    {
        return str_getcsv($data, ' ', '"', "\\");
    }

    public function consumeFrame(string &$data): ?array
    {
        // check for $this->lineBreak
        $p = strpos($data, $this->lineBreak);
        if ($p === false) {
            return null;
        }

        // break on separator
        $frame = substr($data, 0, $p);
        $data = substr($data, $p + strlen($this->lineBreak));

        return $this->unpackFrame($frame);
    }
}