Added all upgrade buttons

Assets/Prefabs/UpgradeButton.prefab

@@ -0,0 +1,46 @@
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Assets/Prefabs/UpgradeButton.prefab.meta

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Assets/Scripts/Game/BasicUpgradeButton.cs

@@ -1,21 +0,0 @@
-using UnityEngine;
-using UnityEngine.UI;
-
-namespace Fruitomation.Game
-{
-    public class BasicUpgradeButton : MonoBehaviour
-    {
-        [Header("Settings")]
-        [SerializeField] private BasicUpgrade Upgrade;
-        [SerializeField] private int UpgradeCost;
-
-        private void Awake()
-        {
-            Button b = GetComponent<Button>();
-            b.onClick.AddListener(() =>
-            {
-                UpgradeManager.Unlock(Upgrade);
-            });
-        }
-    }
-}

Assets/Scripts/UI/BasicUpgradeButton.cs

@@ -0,0 +1,83 @@
+using Fruitomation.Game;
+using UnityEngine.UI;
+using UnityEngine;
+using System.Linq;
+using System;
+
+namespace Fruitomation.UI
+{
+    public class BasicUpgradeButton : MonoBehaviour
+    {
+        private enum UpgradeState
+        {
+            Unlocked,
+            Unlockable,
+            Viewable,
+            Hidden,
+        }
+
+        [Header("Settings")]
+        [SerializeField] private BasicUpgrade Upgrade;
+        [SerializeField] private int UpgradeCost;
+
+        [Header("References")]
+        [SerializeField] private BasicUpgradeButton[] RequiredUpgrades;
+
+        private UpgradeState State = UpgradeState.Hidden;
+        private Button AttachedButton;
+        private Text AttachedText;
+        
+        private void Awake()
+        {
+            AttachedText = gameObject.GetComponentInChildren<Text>();
+            AttachedButton = GetComponent<Button>();
+            
+            AttachedButton.onClick.AddListener(() =>
+            {
+                UpgradeManager.Unlock(Upgrade);
+            });
+
+            /* Stops null reference */
+            RequiredUpgrades ??= Array.Empty<BasicUpgradeButton>();
+        }
+
+        private bool IsUnlockable =>
+            RequiredUpgrades.Length == 0 ||
+            RequiredUpgrades.All(required => required.IsUnlocked);
+
+        private bool IsViewable =>
+            RequiredUpgrades.Length == 0 ||
+            RequiredUpgrades.Any(required => required.IsUnlocked);
+        
+        private void Update()
+        {
+            if (UpgradeManager.Is(Upgrade))
+            {
+                State = UpgradeState.Unlocked;
+            }
+            
+            else if (IsUnlockable)
+            {
+                State = UpgradeState.Unlockable;
+            }
+            
+            else if (IsViewable)
+            {
+                State = UpgradeState.Viewable;
+            }
+
+            else
+            {
+                State = UpgradeState.Hidden;
+            }
+            
+            //
+
+            AttachedText.text = State == UpgradeState.Hidden
+                ? "???"
+                : $"{Upgrade.ToString()} [{UpgradeCost}]";
+        }
+        
+        private bool IsUnlocked => State == UpgradeState.Unlocked;
+    }
+}