feature: construct from other ulid

closes #55
PhpGt · Sep 13, 2023 · 8e64144 · 8e64144
1 parent 7540b26
commit 8e64144
Show file tree

Hide file tree

Showing 6 changed files with 231 additions and 34 deletions.
diff --git a/src/Base32.php b/src/Base32.php
@@ -0,0 +1,51 @@
+<?php
+namespace Gt\Ulid;
+
+class Base32 {
+	public function __construct(
+		private string $skipCharacters = "ilou"
+	) {}
+
+	public function fromDec(int $base10):string {
+		$skipCharacters = str_split($this->skipCharacters);
+
+		$base10 = abs($base10);
+		$converted = base_convert((string)$base10, 10, 32);
+
+		for($i = 0, $len = strlen($converted); $i < $len; $i++) {
+			$ord = ord($converted[$i]);
+			foreach($skipCharacters as $skip) {
+				$skipOrd = ord($skip);
+				if($ord >= $skipOrd) {
+					$ord++;
+				}
+				$converted[$i] = chr($ord);
+			}
+		}
+
+		return strtoupper($converted);
+	}
+
+	public function toDec(string $base32): int {
+		$skipCharacters = str_split($this->skipCharacters);
+		$base32 = strtoupper($base32);
+
+		for ($i = 0, $len = strlen($base32); $i < $len; $i++) {
+			$ord = ord($base32[$i]);
+			$adjustment = 0;
+
+			foreach ($skipCharacters as $skip) {
+				$skipOrd = ord(strtoupper($skip));
+				if ($ord > $skipOrd) {
+					$adjustment++;
+				}
+			}
+
+			$ord -= $adjustment;
+			$base32[$i] = chr($ord);
+		}
+
+		return intval(base_convert($base32, 32, 10));
+	}
+
+}
diff --git a/src/Extractor.php b/src/Extractor.php
@@ -0,0 +1,58 @@
+<?php
+namespace Gt\Ulid;
+
+class Extractor {
+	private Base32 $base32;
+
+	public function __construct(
+		private int $length = Ulid::DEFAULT_TOTAL_LENGTH,
+		private int $timestampLength = Ulid::DEFAULT_TIMESTAMP_LENGTH,
+		?Base32 $base32 = null,
+	) {
+		$this->base32 = $base32 ?? new Base32();
+	}
+
+	public function extractPrefix(string $initString):?string {
+		$underscorePos = strpos($initString, "_");
+		if($underscorePos === false) {
+			return null;
+		}
+
+		return substr($initString, 0, $underscorePos);
+	}
+
+	public function extractTimestamp(string $initString):int {
+		$underscorePos = $this->positionAfterUnderscore($initString);
+
+		$timestampString = substr(
+			$initString,
+			$underscorePos,
+			$this->timestampLength,
+		);
+		return $this->base32->toDec($timestampString);
+	}
+
+	public function extractRandomString(string $initString):string {
+		$underscorePos = $this->positionAfterUnderscore($initString);
+
+		$initString = substr(
+			$initString,
+			$underscorePos,
+		);
+
+		return substr(
+			$initString,
+			$this->timestampLength,
+			$this->length,
+		);
+	}
+
+	protected function positionAfterUnderscore(string $initString):int {
+		$underscorePos = strpos($initString, "_");
+		if($underscorePos) {
+			$underscorePos += 1;
+		}
+
+		return $underscorePos ?: 0;
+	}
+}
diff --git a/src/Ulid.php b/src/Ulid.php
@@ -7,25 +7,37 @@ class Ulid implements Stringable {
 	const DEFAULT_TOTAL_LENGTH = 20;
 	const DEFAULT_TIMESTAMP_LENGTH = 10;
 
-	private float $timestamp;
+	private int $timestamp;
 	private string $randomString;
+	private Base32 $base32;
 
 	public function __construct(
 		private ?string $prefix = null,
-		float|int $timestamp = null,
+		int $timestamp = null,
 		private int $length = self::DEFAULT_TOTAL_LENGTH,
 		private int $timestampLength = self::DEFAULT_TIMESTAMP_LENGTH,
+		string $init = null,
 	) {
+		$this->base32 = new Base32();
+
+		if($init) {
+			$extractor = new Extractor();
+			$this->prefix = $extractor->extractPrefix($init);
+			$this->timestamp = $extractor->extractTimestamp($init);
+			$this->randomString = $extractor->extractRandomString($init);
+			return;
+		}
+
 		if(is_null($timestamp)) {
-			$timestamp = microtime(true);
+			$timestamp = (int)round(microtime(true) * 1000);
 		}
 
 		$this->timestamp = $timestamp;
 
 		$this->randomString = "";
 		for($i = 0; $i < $this->length - $this->timestampLength; $i++) {
 			$rnd = random_int(0, 31);
-			$this->randomString .= $this->base32($rnd);
+			$this->randomString .= $this->base32->fromDec($rnd);
 		}
 	}
 
@@ -38,9 +50,9 @@ public function __toString():string {
 			$randomString,
 		]);
 
-		if($this->prefix) {
+		if($prefix = $this->getPrefix()) {
 			$string = implode("_", [
-				$this->prefix,
+				$prefix,
 				$string,
 			]);
 		}
@@ -49,16 +61,19 @@ public function __toString():string {
 	}
 
 	public function getPrefix():?string {
-		return $this->prefix;
+		if(!$this->prefix) {
+			return null;
+		}
+
+		return strtoupper($this->prefix);
 	}
 
-	public function getTimestamp():float {
+	public function getTimestamp():int {
 		return $this->timestamp;
 	}
 
 	public function getTimestampString():string {
-		$timestamp = round($this->timestamp * 1000);
-		$base32Timestamp = $this->base32((int)$timestamp);
+		$base32Timestamp = $this->base32->fromDec($this->timestamp);
 		return substr(
 			str_pad(
 				$base32Timestamp,
@@ -74,25 +89,4 @@ public function getTimestampString():string {
 	public function getRandomString():string {
 		return $this->randomString;
 	}
-
-	private function base32(int $number):string {
-		$skipCharacters = ["i", "l", "o", "u"];
-		if($number < 0) {
-			$number = -$number;
-		}
-		$converted = base_convert((string)$number, 10, 32);
-
-		for($i = 0, $len = strlen($converted); $i < $len; $i++) {
-			$ord = ord($converted[$i]);
-			foreach($skipCharacters as $skip) {
-				$skipOrd = ord($skip);
-				if($ord >= $skipOrd) {
-					$ord++;
-				}
-				$converted[$i] = chr($ord);
-			}
-		}
-
-		return strtoupper($converted);
-	}
 }
diff --git a/test/phpunit/Base32Test.php b/test/phpunit/Base32Test.php
@@ -0,0 +1,34 @@
+<?php
+namespace Gt\Ulid\Test;
+
+use Gt\Ulid\Base32;
+use PHPUnit\Framework\TestCase;
+
+class Base32Test extends TestCase {
+	public function testFromDec():void {
+		$sut = new Base32();
+		$b32 = $sut->fromDec(105);
+		self::assertSame(105, $sut->toDec($b32));
+	}
+
+	public function testFromDec_timestamp():void {
+		$timestamp = strtotime("5th April 1988 17:24:00");
+		$sut = new Base32();
+		$b32 = $sut->fromDec($timestamp);
+		self::assertSame($timestamp, $sut->toDec($b32));
+	}
+
+	public function testFromDec_timestampWayInTheFuture():void {
+		$timestamp = strtotime("31st December 9999 23:59:59");
+		$sut = new Base32();
+		$b32 = $sut->fromDec($timestamp);
+		self::assertSame($timestamp, $sut->toDec($b32));
+	}
+
+	public function testFromDec_timestampWayInThePast():void {
+		$timestamp = strtotime("1st January -5000 13:05:00");
+		$sut = new Base32();
+		$b32 = $sut->fromDec($timestamp);
+		self::assertSame($timestamp, $sut->toDec($b32));
+	}
+}
diff --git a/test/phpunit/ExtractorTest.php b/test/phpunit/ExtractorTest.php
@@ -0,0 +1,49 @@
+<?php
+namespace Gt\Ulid\Test;
+
+use Gt\Ulid\Extractor;
+use Gt\Ulid\Ulid;
+use PHPUnit\Framework\TestCase;
+
+class ExtractorTest extends TestCase {
+	public function testExtractTimestamp():void {
+		$currentTimestamp = 1694626973857;
+		$ulid = "01HA7T72510000000000";
+
+		$sut = new Extractor();
+		$timestamp = $sut->extractTimestamp($ulid);
+		self::assertSame($currentTimestamp, $timestamp);
+	}
+
+	public function testExtractTimestamp_specificKnownDate():void {
+		$knownTimestamp = strtotime("5th April 1988 17:24:00");
+
+		$ulid = self::createMock(Ulid::class);
+		$ulid->method("__toString")
+			->willReturn("0000H5J61G" . "DYSS02F0S3");
+
+		$sut = new Extractor();
+		$timestamp = $sut->extractTimestamp($ulid);
+		self::assertSame($knownTimestamp, $timestamp);
+	}
+
+	public function testExtractPrefix():void {
+		$ulid = "example_1234567890";
+		$sut = new Extractor();
+		self::assertSame("example", $sut->extractPrefix($ulid));
+	}
+
+	public function testExtractPrefix_noPrefix():void {
+		$ulid = "1234567890";
+		$sut = new Extractor();
+		self::assertNull($sut->extractPrefix($ulid));
+	}
+
+	public function testExtractRandomString():void {
+		$random = "AABBCCDDEE";
+		$timestamp = "0000000000";
+		$ulid = "example_" . $timestamp . $random;
+		$sut = new Extractor();
+		self::assertSame($random, $sut->extractRandomString($ulid));
+	}
+}
diff --git a/test/phpunit/UlidTest.php b/test/phpunit/UlidTest.php
@@ -5,14 +5,18 @@
 use PHPUnit\Framework\TestCase;
 
 class UlidTest extends TestCase {
+	public function testGetPrefix():void {
+		$sut = new Ulid("customer");
+		self::assertStringStartsWith("CUSTOMER_", $sut);
+	}
 	public function testGetTimestamp():void {
 		$sut = new Ulid();
-		$timestamp = microtime(true);
+		$timestamp = round(microtime(true) * 1000);
 		self::assertSame(round($timestamp), round($sut->getTimestamp()));
 	}
 
 	public function testGetTimestamp_setInConstructor():void {
-		$timestamp = (float)strtotime("5th April 1988");
+		$timestamp = strtotime("5th April 1988");
 		$sut = new Ulid(timestamp: $timestamp);
 		self::assertSame($timestamp, $sut->getTimestamp());
 	}
@@ -82,7 +86,14 @@ public function testConstruct_setTimestampLength():void {
 
 	public function testConstruct_prefix():void {
 		$sut = new Ulid("customer");
-		self::assertStringStartsWith("customer_", $sut);
+		self::assertStringStartsWith("CUSTOMER_", $sut);
 		self::assertGreaterThan(strlen("customer_") + 10, strlen($sut));
 	}
+
+	public function testConstruct_existingUlid():void {
+		$existingUlid = new Ulid();
+		$existingString = (string)$existingUlid;
+		$sut = new Ulid(init: $existingString);
+		self::assertSame($existingString, (string)$sut);
+	}
 }