*/ public static function parseList(string $value): array { $out = []; foreach (self::split($value) as $piece) { $address = self::one($piece); if ($address !== null) { $out[] = $address; } } return $out; } public function isEmpty(): bool { return $this->email === ''; } /** The whole address lower-cased, for comparing and looking people up. */ public function normalized(): string { return strtolower($this->email); } /** The part before the last `@`. */ public function local(): string { $at = strrpos($this->email, '@'); return $at === false ? $this->email : substr($this->email, 0, $at); } /** The part after the last `@`, lower-cased. */ public function domain(): string { $at = strrpos($this->email, '@'); return $at === false ? '' : strtolower(substr($this->email, $at + 1)); } /** * The `+detail` part of the local part (RFC 5233 subaddress), or null. * `support+t8f2k@example.com` answers `t8f2k`. */ public function detail(): ?string { $local = $this->local(); $plus = strpos($local, '+'); return $plus === false ? null : substr($local, $plus + 1); } public function __toString(): string { if ($this->name === '') { return $this->email; } return '"' . addcslashes($this->name, '"\\') . '" <' . $this->email . '>'; } /** * Split an address list on the commas that separate addresses, and throw * away group syntax (`Team: a@x, b@y;`), which names a group rather than a * mailbox. * * @return list */ private static function split(string $value): array { $pieces = []; $current = ''; $quoted = false; $depth = 0; $angle = false; $length = \strlen($value); for ($i = 0; $i < $length; $i++) { $c = $value[$i]; if ($quoted) { $current .= $c; if ($c === '\\' && $i + 1 < $length) { $current .= $value[++$i]; } elseif ($c === '"') { $quoted = false; } continue; } if ($depth > 0) { $current .= $c; if ($c === '\\' && $i + 1 < $length) { $current .= $value[++$i]; } elseif ($c === '(') { $depth++; } elseif ($c === ')') { $depth--; } continue; } switch ($c) { case '"': $quoted = true; $current .= $c; break; case '(': $depth = 1; $current .= $c; break; case '<': $angle = true; $current .= $c; break; case '>': $angle = false; $current .= $c; break; case ':': if ($angle) { $current .= $c; } else { // A group name ends here; what came before it is not an address. $current = ''; } break; case ',': case ';': if ($angle) { $current .= $c; } else { $pieces[] = $current; $current = ''; } break; default: $current .= $c; } } $pieces[] = $current; return array_values(array_filter(array_map('trim', $pieces), static fn (string $p): bool => $p !== '')); } private static function one(string $piece): ?self { $comments = []; $plain = self::stripComments($piece, $comments); if (preg_match('/<([^<>]*)>/', $plain, $m)) { $email = trim($m[1]); // A source route (<@relay:user@example.com>) is obsolete syntax; keep the mailbox. if (str_starts_with($email, '@') && str_contains($email, ':')) { $email = substr($email, strpos($email, ':') + 1); } $name = trim(str_replace($m[0], '', $plain)); if ($name === '' && $comments !== []) { $name = trim($comments[0]); } } else { $email = trim($plain); $name = $comments !== [] ? trim($comments[0]) : ''; } $email = trim(self::unquote($email)); $email = preg_replace('/\s+/', '', $email) ?? $email; if ($email === '') { return null; } $name = MimeParser::decodeWords(self::unquote($name)); $name = trim(preg_replace('/\s+/u', ' ', $name) ?? $name); return new self($email, $name); } /** @param list $comments filled with the text of each top-level comment */ private static function stripComments(string $value, array &$comments): string { $out = ''; $comment = ''; $depth = 0; $quoted = false; $length = \strlen($value); for ($i = 0; $i < $length; $i++) { $c = $value[$i]; if ($depth === 0) { if ($quoted) { $out .= $c; if ($c === '\\' && $i + 1 < $length) { $out .= $value[++$i]; } elseif ($c === '"') { $quoted = false; } } elseif ($c === '"') { $quoted = true; $out .= $c; } elseif ($c === '(') { $depth = 1; $comment = ''; } else { $out .= $c; } continue; } if ($c === '\\' && $i + 1 < $length) { $comment .= $value[++$i]; } elseif ($c === '(') { $depth++; $comment .= $c; } elseif ($c === ')') { $depth--; if ($depth === 0) { $comments[] = $comment; $out .= ' '; } else { $comment .= $c; } } else { $comment .= $c; } } return $out; } /** Remove the quotes around quoted-strings and the backslashes inside them. */ private static function unquote(string $value): string { if (!str_contains($value, '"')) { return $value; } return preg_replace_callback( '/"((?:[^"\\\\]|\\\\.)*)"/s', static fn (array $m): string => (string)preg_replace('/\\\\(.)/s', '$1', $m[1]), $value ) ?? $value; } }