Merge branch origin/codex/add-inventory-hotbar-ui into main

Assets/Scripts/UI/InventoryHotbar.cs

@@ -0,0 +1,198 @@
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.UI;
+using BlackRoad.Worldbuilder.Items;
+
+namespace BlackRoad.Worldbuilder.UI
+{
+    /// <summary>
+    /// Renders a subset of the player's inventory as a hotbar UI.
+    /// Use with a horizontal panel containing a SlotTemplate child.
+    /// </summary>
+    public class InventoryHotbar : MonoBehaviour
+    {
+        [Header("References")]
+        [SerializeField] private Inventory inventory;
+        [SerializeField] private GameObject slotTemplate;
+        [SerializeField] private int slotsToShow = 8;
+
+        [Header("Selection")]
+        [SerializeField] private Color selectedColor = Color.white;
+        [SerializeField] private Color normalColor = new Color(1f, 1f, 1f, 0.6f);
+        [SerializeField] private int selectedIndex = 0; // hotbar index, not full inventory index
+
+        private readonly List<GameObject> _slotInstances = new List<GameObject>();
+
+        private void Awake()
+        {
+            if (inventory == null)
+            {
+                // Try to find on player
+                var player = GameObject.FindGameObjectWithTag("Player");
+                if (player != null)
+                {
+                    inventory = player.GetComponent<Inventory>();
+                }
+            }
+
+            if (slotTemplate != null)
+            {
+                slotTemplate.SetActive(false); // hide template
+            }
+
+            BuildSlots();
+        }
+
+        private void OnEnable()
+        {
+            Refresh();
+        }
+
+        private void BuildSlots()
+        {
+            foreach (var go in _slotInstances)
+            {
+                if (go != null)
+                {
+                    Destroy(go);
+                }
+            }
+            _slotInstances.Clear();
+
+            if (slotTemplate == null)
+            {
+                return;
+            }
+
+            for (int i = 0; i < slotsToShow; i++)
+            {
+                var slotInstance = Instantiate(slotTemplate, slotTemplate.transform.parent);
+                slotInstance.name = $"Slot_{i}";
+                slotInstance.SetActive(true);
+                _slotInstances.Add(slotInstance);
+            }
+        }
+
+        private void Update()
+        {
+            HandleSelectionInput();
+            Refresh();
+        }
+
+        private void HandleSelectionInput()
+        {
+            // 1..slotsToShow selects
+            for (int i = 0; i < slotsToShow && i < 9; i++)
+            {
+                if (Input.GetKeyDown(KeyCode.Alpha1 + i))
+                {
+                    selectedIndex = i;
+                }
+            }
+        }
+
+        public void Refresh()
+        {
+            if (inventory == null || _slotInstances.Count == 0)
+            {
+                return;
+            }
+
+            var invSlots = inventory.Slots;
+
+            for (int hotbarIndex = 0; hotbarIndex < _slotInstances.Count; hotbarIndex++)
+            {
+                GameObject slotObj = _slotInstances[hotbarIndex];
+                if (slotObj == null)
+                {
+                    continue;
+                }
+
+                Image bg = slotObj.GetComponent<Image>();
+                if (bg != null)
+                {
+                    bg.color = hotbarIndex == selectedIndex ? selectedColor : normalColor;
+                }
+
+                int invIndex = hotbarIndex;
+
+                ItemDefinition item = null;
+                int count = 0;
+
+                if (invIndex >= 0 && invIndex < invSlots.Count)
+                {
+                    var slot = invSlots[invIndex];
+                    item = slot.item;
+                    count = slot.count;
+                }
+
+                Image iconImage = null;
+                Text countText = null;
+
+                foreach (Transform child in slotObj.transform)
+                {
+                    if (child.name.ToLower().Contains("icon"))
+                    {
+                        iconImage = child.GetComponent<Image>();
+                    }
+
+                    if (child.name.ToLower().Contains("count"))
+                    {
+                        countText = child.GetComponent<Text>();
+                    }
+                }
+
+                if (iconImage != null)
+                {
+                    if (item != null && item.Icon != null)
+                    {
+                        iconImage.enabled = true;
+                        iconImage.sprite = item.Icon;
+                        iconImage.color = item.IconTint;
+                    }
+                    else
+                    {
+                        iconImage.enabled = false;
+                    }
+                }
+
+                if (countText != null)
+                {
+                    if (item != null && count > 0)
+                    {
+                        countText.text = count.ToString();
+                    }
+                    else
+                    {
+                        countText.text = string.Empty;
+                    }
+                }
+            }
+        }
+
+        /// <summary>
+        /// Returns the currently selected ItemDefinition, if any.
+        /// </summary>
+        public ItemDefinition GetSelectedItem()
+        {
+            if (inventory == null)
+            {
+                return null;
+            }
+
+            var slots = inventory.Slots;
+            if (selectedIndex < 0 || selectedIndex >= slots.Count)
+            {
+                return null;
+            }
+
+            var slot = slots[selectedIndex];
+            return slot.item;
+        }
+
+        /// <summary>
+        /// Returns current hotbar selection index (0-based).
+        /// </summary>
+        public int GetSelectedIndex() => selectedIndex;
+    }
+}