50 lines
1.3 KiB
PHP
50 lines
1.3 KiB
PHP
<?php
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namespace NoccyLabs\React\Http2\Huffman;
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class Codec
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{
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private Dictionary $dictionary;
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const CODE_EOS = 256;
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public function __construct(Dictionary $dictionary)
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{
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$this->dictionary = $dictionary;
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}
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public function decode(string $data): ?string
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{
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$in = array_map("ord", str_split($data));
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$out = [];
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$bits = '';
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for ($ch = 0; $ch < count($in); $ch++) {
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$bits .= str_pad(decbin($in[$ch]), 8, "0", STR_PAD_LEFT);
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while (($code = $this->dictionary->match($bits)) !== null) {
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if ($code === self::CODE_EOS) break(2);
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$out[] = $code;
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}
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}
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return join("", array_map("chr", $out));
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}
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public function encode(string $data): ?string
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{
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$in = array_map("ord", str_split($data));
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//$in[] = self::CODE_EOS;
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$out = [];
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$bits = '';
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for ($ch = 0; $ch < count($in); $ch++) {
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$bits .= $this->dictionary->pattern($in[$ch]);
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while (strlen($bits) >= 8) {
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$out[] = bindec(substr($bits, 0, 8));
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$bits = substr($bits, 8);
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}
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}
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if (strlen($bits) > 0) {
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$out[] = bindec(str_pad($bits, 8, "1", STR_PAD_RIGHT));
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}
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return join("", array_map("chr", $out));
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}
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} |