Implement adding tags

lib/pages/AddPage.dart

@@ -1,6 +1,15 @@
 import 'package:flutter/material.dart';
+import 'package:flutter/widgets.dart';
 import 'package:libac_dart/nbt/Tag.dart';
+import 'package:libac_dart/nbt/impl/ByteArrayTag.dart';
+import 'package:libac_dart/nbt/impl/IntArrayTag.dart';
+import 'package:libac_dart/nbt/impl/ListTag.dart';
+import 'package:libac_dart/nbt/impl/LongArrayTag.dart';
 import 'package:nbteditor/Constants.dart';
+import 'package:nbteditor/pages/EditValue.dart';
+import 'package:nbteditor/pages/RenamePrompt.dart';
+
+import '../tags/Tag.dart';
 
 class AddPage extends StatefulWidget {
   const AddPage({super.key});
@@ -10,26 +19,146 @@ class AddPage extends StatefulWidget {
 }
 
 class AddState extends State<AddPage> {
+  List<TagType> allowedTagTypes = [];
+  bool canAddAnyType = false;
+  bool isList = false;
+  bool isArray = false;
+  String newTagName = "";
+  dynamic val;
+  Tag? ParentTag;
+  bool singleShot = true;
+
+  Function? didChangeState;
+
   @override
   void didChangeDependencies() {
     var args = ModalRoute.of(context)!.settings.arguments as AddElementArgs;
+
+    canAddAnyType = args.allowAllTagTypes;
+    isList = args.tag.getTagType() == TagType.List;
+    isArray = args.tag.getTagType() == TagType.ByteArray ||
+        args.tag.getTagType() == TagType.IntArray ||
+        args.tag.getTagType() == TagType.LongArray;
+
+    if (isList || isArray) {
+      allowedTagTypes = args.allowedTagTypes;
+    }
+
+    if (canAddAnyType) {
+      allowedTagTypes.clear();
+      for (TagType type in TagType.values) {
+        if (type == TagType.End) {
+          continue;
+        } else {
+          allowedTagTypes.add(type);
+        }
+      }
+    }
+
+    didChangeState = args.didChangeState;
+    ParentTag = args.tag;
+  }
+
+  Future<void> processTagType(TagType type) async {
+    if (!(isArray || isList)) {
+      var reply = await showDialog(
+          context: context,
+          routeSettings: RouteSettings(arguments: ""),
+          builder: (builder) {
+            return RenamePrompt();
+          });
+      newTagName = reply as String;
+    }
+    var nTag = Tag.makeTagOfType(type);
+    bool hasValue = true;
+
+    if (type == TagType.List ||
+        type == TagType.ByteArray ||
+        type == TagType.LongArray ||
+        type == TagType.IntArray ||
+        type == TagType.Compound) {
+      hasValue = false;
+    } else {
+      nTag.setKey(newTagName);
+      var reply = await showDialog(
+          context: context,
+          routeSettings: RouteSettings(arguments: nTag),
+          builder: (builder) {
+            return EditValuePrompt();
+          });
+      val = reply;
+    }
+
+    if (isArray) {
+      switch (ParentTag!.getTagType()) {
+        case TagType.LongArray:
+          {
+            LongArrayTag LAT = ParentTag! as LongArrayTag;
+            LAT.value.add(val);
+            break;
+          }
+        case TagType.IntArray:
+          {
+            IntArrayTag IAT = ParentTag! as IntArrayTag;
+            IAT.value.add(val);
+            break;
+          }
+
+        case TagType.ByteArray:
+          {
+            ByteArrayTag BAT = ParentTag! as ByteArrayTag;
+            BAT.value.add(val);
+            break;
+          }
+        default:
+          {
+            break;
+          }
+      }
+    } else {
+      if (hasValue) nTag.setValue(val);
+
+      if (isList) {
+        ListTag lst = ParentTag! as ListTag;
+        lst.add(nTag);
+      } else {
+        ParentTag!.asCompoundTag().put(newTagName, nTag);
+      }
+    }
+
+    didChangeState!.call();
+    Navigator.pop(context);
   }
 
   @override
   Widget build(BuildContext context) {
+    if (isList || isArray && !canAddAnyType && singleShot) {
+      singleShot = false;
+
+      Future.delayed(Duration(seconds: 2), () {
+        processTagType(allowedTagTypes[0]);
+      });
+    }
+
     return Scaffold(
       appBar: AppBar(
-        title: const Text("Add Tag"),
+        title: const Text("Add Tag - Select Tag Type"),
         backgroundColor: Constants.TITLEBAR_COLOR,
       ),
-      body: const Padding(
-        padding: EdgeInsets.all(8),
-        child: SingleChildScrollView(
-          child: Column(
-            children: [],
-          ),
-        ),
-      ),
+      body: Padding(
+          padding: EdgeInsets.all(8),
+          child: ListView.builder(
+            itemBuilder: (builder, index) {
+              return ListTile(
+                title: Text(allowedTagTypes[index].name),
+                leading: TagExt.getTagIcon(allowedTagTypes[index]),
+                onTap: () async {
+                  processTagType(allowedTagTypes[index]);
+                },
+              );
+            },
+            itemCount: allowedTagTypes.length,
+          )),
     );
   }
 }
@@ -38,6 +167,7 @@ class AddElementArgs {
   Tag tag;
   bool allowAllTagTypes;
   bool isArray;
+  Function didChangeState;
 
   List<TagType> allowedTagTypes;
 
@@ -45,5 +175,6 @@ class AddElementArgs {
       {required this.tag,
       required this.allowAllTagTypes,
       required this.isArray,
-      this.allowedTagTypes = const []});
+      this.allowedTagTypes = const [],
+      required this.didChangeState});
 }