feat: initial functional release of Stock Pignon

app/src/main/java/com/stock/pignon/CartViewHelper.java

@@ -0,0 +1,165 @@
+// CartViewHelper.java
+package com.stock.pignon;
+
+import android.app.Activity;
+import android.content.Context;
+import android.graphics.Color;
+import android.graphics.Typeface;
+import android.graphics.drawable.GradientDrawable;
+import android.util.TypedValue;
+import android.view.Gravity;
+import android.view.View;
+import android.widget.Button;
+import android.widget.ImageView;
+import android.widget.LinearLayout;
+import android.widget.TextView;
+
+import java.util.List;
+
+/**
+ * UI Helper to dynamically build and update cart's list
+ */
+public class CartViewHelper {
+
+    /**
+     * Refreshes the entire cart side-panel or list
+     * Clears everything and rebuild on current CartManager data
+     */
+    public static void updateCartView(LinearLayout cartList, Context context) {
+        if (cartList == null) return;
+
+        // Clear and get current items
+        cartList.removeAllViews();
+        List<CartItem> cartItems = CartManager.getItems();
+
+        // If empty cart, show it to user
+        if (cartItems.isEmpty()) {
+            TextView empty = new TextView(context);
+            empty.setText(context.getString(R.string.cart_empty));
+            empty.setTextSize(TypedValue.COMPLEX_UNIT_SP, 20);
+            empty.setGravity(Gravity.CENTER);
+            empty.setPadding(0, 50, 0, 0);
+            cartList.addView(empty);
+
+            updateTotalDisplay(context, 0, 0);
+            return;
+        }
+
+        // Build list and calculate total at the same time
+        int totalMin = 0;
+        int totalMax = 0;
+
+        for (CartItem item : cartItems) {
+            totalMin += item.getTotalMin();
+            totalMax += item.getTotalMax();
+
+            // Create and add the row view
+            cartList.addView(createCartItemView(item, cartList, context));
+        }
+
+        // Display global price range at the end
+        updateTotalDisplay(context, totalMin, totalMax);
+    }
+
+    /**
+     * Updates the global price range at the bottom of the screen
+     */
+    private static void updateTotalDisplay(Context context, int min, int max) {
+        TextView totalView = ((Activity) context).findViewById(R.id.totalView);
+        if (totalView != null) {
+            // Using string resources
+            totalView.setText(context.getString(R.string.price_range, min, max, "€"));
+        }
+    }
+
+    /**
+     * Creates a horizontal row for a single cart item
+     * Layout: [image] [name / [quantity / price]] [remove button]
+     */
+    private static View createCartItemView(CartItem item, LinearLayout cartList, Context context) {
+        LinearLayout row = new LinearLayout(context);
+        row.setOrientation(LinearLayout.HORIZONTAL);
+        row.setGravity(Gravity.CENTER_VERTICAL);
+
+        // Layout parameters
+        LinearLayout.LayoutParams rowParams = new LinearLayout.LayoutParams(
+                LinearLayout.LayoutParams.MATCH_PARENT,
+                LinearLayout.LayoutParams.WRAP_CONTENT);
+        rowParams.setMargins(0, 10, 0, 10);
+        row.setLayoutParams(rowParams);
+
+        // Image
+        ImageView image = new ImageView(context);
+        ImageLoader.loadImage(image, item.getImageFile(),200,200);
+        LinearLayout.LayoutParams imgParams = new LinearLayout.LayoutParams(100, 100);
+        imgParams.setMargins(0, 0, 20, 0);
+        image.setLayoutParams(imgParams);
+        row.addView(image);
+
+        // Sublayout for name + [quantity + price]
+        LinearLayout infoLayout = new LinearLayout(context);
+        infoLayout.setOrientation(LinearLayout.VERTICAL);
+        infoLayout.setLayoutParams(new LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT, 1f));
+
+        // Name
+        TextView nameView = new TextView(context);
+        nameView.setText(item.getName());
+        nameView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 18);
+        nameView.setTypeface(null, Typeface.BOLD);
+        infoLayout.addView(nameView);
+
+        // Quantity and price range
+        TextView detailsView = new TextView(context);
+        String details = context.getString(R.string.cart_item, item.getQuantity(), item.getTotalMin(), item.getTotalMax());
+        detailsView.setText(details);
+        detailsView.setTextSize(TypedValue.COMPLEX_UNIT_SP, 14);
+        infoLayout.addView(detailsView);
+
+        row.addView(infoLayout);
+
+        // Remove button
+        row.addView(createRemoveButton(item, cartList, context));
+
+        return row;
+    }
+
+    /**
+     * Creates the delete button
+     */
+    private static Button createRemoveButton(CartItem item, LinearLayout cartList, Context context) {
+        Button btn = new Button(context);
+        btn.setText("✖");
+        btn.setTextSize(18);
+        btn.setTextColor(Color.WHITE);
+        btn.setGravity(Gravity.CENTER);
+
+        // Conversion DP to PX for consistent size on all screens
+        float scale = context.getResources().getDisplayMetrics().density;
+        int sizePx = (int) (48 * scale + 0.5f);
+
+        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(sizePx, sizePx);
+        btn.setLayoutParams(params);
+
+        // Background: grey rounded rectangle (API 17 fallback)
+        GradientDrawable shape = new GradientDrawable();
+        shape.setColor(Color.parseColor("#E53935")); // Reddish to indicate delete
+        shape.setCornerRadius(4 * scale);
+        btn.setBackground(shape);
+
+        btn.setOnClickListener(v -> {
+            // setting quantity to 0 removes the item
+            CartManager.addOrUpdateItem(
+                    item.getName(),
+                    item.getMinPrice(),
+                    item.getMaxPrice(),
+                    0, // Setting quantity to 0 triggers removal
+                    item.getImageFile()
+            );
+
+            // visual refresh of the cart list
+            updateCartView(cartList, context);
+        });
+
+        return btn;
+    }
+}