added inventory and stamina system

Assets/Scripts/Player.cs

@@ -1,6 +1,65 @@
 using UnityEngine;
 
+/// <summary>
+/// Core player stats: health and stamina.
+/// Stamina drains while sprinting, regens when not.
+/// If stamina hits zero the player is exhausted and can't sprint again until it fully refills.
+/// </summary>
 public class Player : MonoBehaviour
 {
-    public float health;
+    [Header("Health")]
+    public float maxHealth   = 100f;
+    public float health      = 100f;
+
+    [Header("Stamina")]
+    public float maxStamina       = 100f;
+    public float stamina          = 100f;
+    public float staminaDrain     = 22f;   // per second while sprinting
+    public float staminaRegen     = 12f;   // per second while not sprinting
+    public float regenDelay       = 1.2f;  // seconds after stopping sprint before regen kicks in
+
+    // ─── State ───────────────────────────────────────────────────────
+    [HideInInspector] public bool isSprinting   = false;
+    [HideInInspector] public bool isExhausted   = false;  // true until stamina fully refills
+
+    private float _regenTimer = 0f;
+
+    // ─────────────────────────────────────────────────────────────────
+    void Update()
+    {
+        if (isSprinting && !isExhausted)
+        {
+            stamina -= staminaDrain * Time.deltaTime;
+            _regenTimer = 0f;
+
+            if (stamina <= 0f)
+            {
+                stamina    = 0f;
+                isExhausted = true;
+            }
+        }
+        else
+        {
+            // Count down regen delay
+            _regenTimer += Time.deltaTime;
+
+            if (_regenTimer >= regenDelay)
+            {
+                stamina = Mathf.MoveTowards(stamina, maxStamina, staminaRegen * Time.deltaTime);
+
+                // Clear exhaustion only once fully refilled
+                if (isExhausted && stamina >= maxStamina)
+                    isExhausted = false;
+            }
+        }
+
+        health  = Mathf.Clamp(health,  0f, maxHealth);
+        stamina = Mathf.Clamp(stamina, 0f, maxStamina);
+    }
+
+    // ─── Helpers other scripts can call ──────────────────────────────
+    public bool CanSprint() => !isExhausted && stamina > 0f;
+
+    public float HealthFraction   => health  / maxHealth;
+    public float StaminaFraction  => stamina / maxStamina;
 }