Navigator: Sort files and folders alphanumerically

modules/decima-ui/src/main/java/com/shade/decima/ui/navigator/impl/NavigatorFolderNode.java

@@ -4,6 +4,7 @@
 import com.shade.decima.ui.navigator.NavigatorPath;
 import com.shade.decima.ui.navigator.NavigatorSettings;
 import com.shade.platform.model.runtime.ProgressMonitor;
+import com.shade.platform.model.util.AlphanumericComparator;
 import com.shade.util.NotNull;
 import com.shade.util.Nullable;
 
@@ -13,7 +14,7 @@
 public class NavigatorFolderNode extends NavigatorNode {
     private static final Comparator<NavigatorNode> CHILDREN_COMPARATOR = Comparator
         .comparingInt((NavigatorNode node) -> node instanceof NavigatorFolderNode ? -1 : 1)
-        .thenComparing(NavigatorNode::getLabel);
+        .thenComparing(NavigatorNode::getLabel, AlphanumericComparator.getInstance());
 
     private final FilePath path;
 

modules/platform-model/src/main/java/com/shade/platform/model/util/AlphanumericComparator.java

@@ -0,0 +1,60 @@
+package com.shade.platform.model.util;
+
+import com.shade.util.NotNull;
+
+import java.util.Comparator;
+
+public class AlphanumericComparator implements Comparator<CharSequence> {
+    private static final AlphanumericComparator INSTANCE = new AlphanumericComparator();
+
+    private AlphanumericComparator() {
+        // prevents instantiation
+    }
+
+    @NotNull
+    public static AlphanumericComparator getInstance() {
+        return INSTANCE;
+    }
+
+    @Override
+    public int compare(CharSequence o1, CharSequence o2) {
+        final int len1 = o1.length();
+        final int len2 = o2.length();
+
+        int i = 0;
+        int j = 0;
+
+        while (i < len1 && j < len2) {
+            final char ch1 = o1.charAt(i);
+            final char ch2 = o2.charAt(i);
+
+            if (Character.isDigit(ch1) && Character.isDigit(ch2)) {
+                int num1 = 0;
+                int num2 = 0;
+
+                while (i < len1 && Character.isDigit(o1.charAt(i))) {
+                    num1 = num1 * 10 + Character.digit(o1.charAt(i), 10);
+                    i += 1;
+                }
+
+                while (j < len2 && Character.isDigit(o2.charAt(j))) {
+                    num2 = num2 * 10 + Character.digit(o2.charAt(j), 10);
+                    j += 1;
+                }
+
+                if (num1 != num2) {
+                    return num1 - num2;
+                }
+            } else {
+                if (ch1 != ch2) {
+                    return ch1 - ch2;
+                }
+
+                i += 1;
+                j += 1;
+            }
+        }
+
+        return len1 - len2;
+    }
+}

modules/platform-model/src/test/java/com/shade/platform/util/AlphanumericComparatorTest.java

@@ -0,0 +1,70 @@
+package com.shade.platform.util;
+
+import com.shade.platform.model.util.AlphanumericComparator;
+import com.shade.util.NotNull;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+
+public class AlphanumericComparatorTest {
+    @Test
+    public void alphanumericComparatorTest() {
+        alphanumericComparatorTestImpl(
+            List.of("img12", "img10", "img2", "img1", "img100_1", "img100_11", "img100", "img100_10", "img100_5"),
+            List.of("img1", "img2", "img10", "img12", "img100", "img100_1", "img100_5", "img100_10", "img100_11")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("file1000", "file100", "file10", "file2", "file1", "file11", "file200", "file20", "file2a", "file2b"),
+            List.of("file1", "file2", "file2a", "file2b", "file10", "file11", "file20", "file100", "file200", "file1000")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("doc10", "doc2", "doc20", "doc1", "doc3", "doc15", "doc4"),
+            List.of("doc1", "doc2", "doc3", "doc4", "doc10", "doc15", "doc20")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("page2", "page12", "page3", "page22", "page4", "page13", "page23"),
+            List.of("page2", "page3", "page4", "page12", "page13", "page22", "page23")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("item-5", "item-1", "item-10", "item-2", "item-11", "item-3", "item-20", "item-15"),
+            List.of("item-1", "item-2", "item-3", "item-5", "item-10", "item-11", "item-15", "item-20")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("abc123def45", "abc12def345", "abc1234def5", "abc12345def4", "abc1234def45", "abc12345def456"),
+            List.of("abc12def345", "abc123def45", "abc1234def5", "abc1234def45", "abc12345def4", "abc12345def456")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("file01_v2", "file02_v1", "file10_v10", "file02_v10", "file10_v2", "file1_v10"),
+            List.of("file01_v2", "file1_v10", "file02_v1", "file02_v10", "file10_v2", "file10_v10")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("chapter-2.1.1", "chapter-10.1.1", "chapter-2.1.10", "chapter-10.1.2", "chapter-2.1.2"),
+            List.of("chapter-2.1.1", "chapter-2.1.2", "chapter-2.1.10", "chapter-10.1.1", "chapter-10.1.2")
+        );
+
+        alphanumericComparatorTestImpl(
+            List.of("item_1_2_3", "item_2_1_3", "item_1_10_3", "item_2_2_1", "item_1_2_10", "item_2_1_10", "item_1_10_1"),
+            List.of("item_1_2_3", "item_1_2_10", "item_1_10_1", "item_1_10_3", "item_2_1_3", "item_2_1_10", "item_2_2_1")
+        );
+    }
+
+    private void alphanumericComparatorTestImpl(
+        @NotNull Collection<? extends CharSequence> input,
+        @NotNull Collection<? extends CharSequence> expected
+    ) {
+        final ArrayList<? extends CharSequence> sorted = new ArrayList<>(input);
+        sorted.sort(AlphanumericComparator.getInstance());
+
+        Assertions.assertEquals(expected, sorted);
+    }
+}