Added Specification Pattern

Author: jkapuscik3

behavioral/Specification/AgeSpecification.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class AgeSpecification implements Specification {
+
+    private int $maxAge;
+
+    public function __construct(int $maxAge)
+    {
+        $this->maxAge = $maxAge;
+    }
+
+    public function isSatisfiedBy(Candidate $candidate) : bool
+    {
+        return $candidate->getAge() <= $this->maxAge;
+    }
+
+}

behavioral/Specification/AndSpecification.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class AndSpecification implements Specification {
+
+    private array $specifications;
+
+    public function __construct(Specification ...$specifications)
+    {
+        $this->specifications = $specifications;
+    }
+
+    public function isSatisfiedBy(Candidate $candidate): bool
+    {
+        foreach ($this->specifications as $specification) {
+            if (! $specification->isSatisfiedBy($candidate)) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+}

behavioral/Specification/Candidate.php

@@ -0,0 +1,40 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class Candidate
+{
+    private int $age;
+    private array $workExperience;
+    private array $education;
+    private bool $isConvicted;
+
+    public function __construct(int $age, array $workExperience, array $education, bool $isConvicted)
+    {
+        $this->age = $age;
+        $this->workExperience = $workExperience;
+        $this->education = $education;
+        $this->isConvicted = $isConvicted;
+    }
+
+    public function getAge(): int
+    {
+        return $this->age;
+    }
+
+    public function getWorkExperience(): array
+    {
+        return $this->workExperience;
+    }
+
+    public function getEducation()
+    {
+        return $this->education;
+    }
+
+    public function isConvicted(): bool
+    {
+        return $this->isConvicted;
+    }
+
+}

behavioral/Specification/ConvictedSpecification.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class ConvictedSpecification implements Specification
+{
+
+    public function isSatisfiedBy(Candidate $candidate): bool
+    {
+        return $candidate->isConvicted();
+    }
+}

behavioral/Specification/Education.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Behavioral\Specification;
+
+use DateTime;
+
+class Education {
+
+    private string $university;
+    private DateTime $start;
+    private DateTime $end;
+
+    public function __construct(string $university, DateTime $start, DateTime $end)
+    {
+        $this->university = $university;
+        $this->start = $start;
+        $this->end = $end;
+    }
+
+    public function getEndDate() : DateTime {
+        return $this->end;
+    }
+
+}

behavioral/Specification/NotSpecification.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class NotSpecification implements Specification
+{
+    private Specification $specification;
+
+    public function __construct(Specification $specification)
+    {
+        $this->specification = $specification;
+    }
+
+    public function isSatisfiedBy(Candidate $candidate): bool
+    {
+        return !$this->specification->isSatisfiedBy($candidate);
+    }
+}

behavioral/Specification/OrSpecification.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Behavioral\Specification;
+
+class OrSpecification implements Specification {
+
+    private array $specifications;
+
+    public function __construct(Specification ...$specifications)
+    {
+        $this->specifications = $specifications;
+    }
+
+    public function isSatisfiedBy(Candidate $candidate): bool
+    {
+        foreach ($this->specifications as $specification) {
+            if ($specification->isSatisfiedBy($candidate)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

behavioral/Specification/RecentGraduateSpecification.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Behavioral\Specification;
+
+use DateTime;
+use DateInterval;
+
+class RecentGraduateSpecification implements Specification
+{
+    private const HYSTERESIS = 12; // months
+
+    public function isSatisfiedBy(Candidate $candidate): bool
+    {
+        $maxEndDate = (new DateTime())->sub(new DateInterval(sprintf("P%dM", self::HYSTERESIS)));
+
+        foreach ($candidate->getEducation() as $education) {
+            if ($education->getEndDate() < new DateTime()
+                && $education->getEndDate() > $maxEndDate) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

behavioral/Specification/Specification.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace Behavioral\Specification;
+
+interface Specification
+{
+    public function isSatisfiedBy(Candidate $candidate) : bool;
+}

behavioral/Specification/StudentSpecification.php

@@ -0,0 +1,19 @@
+<?php
+
+namespace Behavioral\Specification;
+
+use DateTime;
+
+class StudentSpecification implements Specification {
+
+    public function isSatisfiedBy(Candidate $candidate) : bool
+    {
+        foreach ($candidate->getEducation() as $education) {
+            if ($education->getEndDate() > new DateTime()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}