chadmando · May 14, 2024 16:22 · May 10, 2024
diff --git a/CeilingFan.ps1 b/CeilingFan.ps1
@@ -0,0 +1,59 @@
+<#
+    Allow an object to alter its behavior when its internal state changes.
+    The object will appear to change its class.
+
+    The State pattern puts each branch of the conditional in a separate class.
+
+    This lets you treat the object's state as an object in its own right
+    that can vary independently from other objects
+#>
+
+class CeilingFanState {
+    Change([CeilingFan] $ceilingFan) {
+        throw "not implemented"
+    }
+}
+
+class CeilingFanOff : CeilingFanState {
+    Change([CeilingFan] $context) {
+        $context.State = [CeilingFanLow]::new()
+        "Change state from Off to Low." | Out-Host
+    }
+}
+
+class CeilingFanLow: CeilingFanState {
+    Change([CeilingFan] $context) {
+        $context.State = [CeilingFanMedium]::new()
+        "Change state from Low to Medium." | Out-Host
+    }
+}
+
+class CeilingFanMedium: CeilingFanState {
+    Change([CeilingFan] $context) {
+        $context.State = [CeilingFanHigh]::new()
+        "Change state from Medium to High." | Out-Host
+    }
+}
+
+class CeilingFanHigh: CeilingFanState {
+    Change([CeilingFan] $context) {
+        $context.State = [CeilingFanLow]::new()
+        "Change state from High to Off." | Out-Host
+    }
+}
+
+class CeilingFan {
+
+    $State
+
+    CeilingFan ([CeilingFanState] $state) { $this.State = $state }
+
+    Pull() { $this.State.Change($this) }
+}
+
+$ceilingFan = [CeilingFan]::new([CeilingFanOff]::new())
+
+$ceilingFan.Pull()
+$ceilingFan.Pull()
+$ceilingFan.Pull()
+$ceilingFan.Pull()