Add initial NAPI and JS generator.

Author: tritao

src/Generator/Driver.cs

@@ -47,6 +47,8 @@ Generator CreateGeneratorFromKind(GeneratorKind kind)
                     return new CSharpGenerator(Context);
                 case GeneratorKind.QuickJS:
                     return new QuickJSGenerator(Context);
+                case GeneratorKind.NAPI:
+                    return new NAPIGenerator(Context);
             }
 
             throw new NotImplementedException();

src/Generator/Generator.cs

@@ -17,7 +17,8 @@ public enum GeneratorKind
         ObjectiveC,
         Java,
         Swift,
-        QuickJS
+        QuickJS,
+        NAPI
     }
 
     /// <summary>

src/Generator/Generators/C/NAPI/NAPIGenerator.cs

@@ -0,0 +1,72 @@
+using System.Collections.Generic;
+using CppSharp.AST;
+using CppSharp.Generators.Cpp;
+
+namespace CppSharp.Generators.C
+{
+    /// <summary>
+    /// N-API generator responsible for driving the generation of binding files.
+    /// N-API documentation: https://nodejs.org/api/n-api.html
+    /// </summary>
+    public class NAPIGenerator : CppGenerator
+    {
+        public NAPIGenerator(BindingContext context) : base(context)
+        {
+        }
+
+        public override List<GeneratorOutput> Generate()
+        {
+            var outputs = base.Generate();
+
+            foreach (var module in Context.Options.Modules)
+            {
+                if (module == Context.Options.SystemModule)
+                    continue;
+
+                var output = GenerateModule(module);
+                if (output != null)
+                {
+                    OnUnitGenerated(output);
+                    outputs.Add(output);
+                }
+            }
+
+            return outputs;
+        }
+
+        public override List<CodeGenerator> Generate(IEnumerable<TranslationUnit> units)
+        {
+            var outputs = new List<CodeGenerator>();
+
+            var header = new NAPIHeaders(Context, units);
+            outputs.Add(header);
+
+            var source = new NAPISources(Context, units);
+            outputs.Add(source);
+
+            return outputs;
+        }
+
+        public override GeneratorOutput GenerateModule(Module module)
+        {
+            if (module == Context.Options.SystemModule)
+                return null;
+
+            var moduleGen = new NAPIModule(Context, module);
+
+            var output = new GeneratorOutput
+            {
+                TranslationUnit = new TranslationUnit
+                {
+                    FilePath = $"{module.LibraryName}.cpp",
+                    Module = module
+                },
+                Outputs = new List<CodeGenerator> { moduleGen }
+            };
+
+            output.Outputs[0].Process();
+
+            return output;
+        }
+    }
+}

src/Generator/Generators/C/NAPI/NAPIHeaders.cs

@@ -0,0 +1,23 @@
+using System.Collections.Generic;
+using CppSharp.AST;
+
+namespace CppSharp.Generators.Cpp
+{
+    /// <summary>
+    /// Generates Node N-API C/C++ header files.
+    /// N-API documentation: https://nodejs.org/api/n-api.html
+    /// </summary>
+    public class NAPIHeaders : CppHeaders
+    {
+        public NAPIHeaders(BindingContext context, IEnumerable<TranslationUnit> units)
+            : base(context, units)
+        {
+            CTypePrinter.PushContext(TypePrinterContextKind.Managed);
+        }
+
+        public override void Process()
+        {
+            base.Process();
+        }
+    }
+}

src/Generator/Generators/C/NAPI/NAPIModule.cs

@@ -0,0 +1,43 @@
+using System.Collections.Generic;
+using CppSharp.AST;
+using CppSharp.Generators.C;
+
+namespace CppSharp.Generators.Cpp
+{
+    /// <summary>
+    /// Generates Node N-API C/C++ module init files.
+    /// N-API documentation: https://nodejs.org/api/n-api.html
+    /// </summary>
+    public class NAPIModule : CCodeGenerator
+    {
+        public NAPIModule(BindingContext context, Module module)
+            : base(context, module.Units.GetGenerated())
+        {
+            CTypePrinter.PushContext(TypePrinterContextKind.Managed);
+        }
+
+        public override string FileExtension { get; } = "cpp";
+
+        public override void Process()
+        {
+            var include = new CInclude()
+            {
+                File = "node/node_api.h",
+                Kind = CInclude.IncludeKind.Angled
+            };
+
+            WriteInclude(include);
+            NewLine();
+
+            WriteLine("NAPI_MODULE_INIT()");
+            WriteOpenBraceAndIndent();
+
+            WriteLine("napi_value result;");
+            WriteLine("NAPI_CALL(env, napi_create_object(env, &result));");
+
+            WriteLine("return result;");
+
+            UnindentAndWriteCloseBrace();
+        }
+    }
+}

src/Generator/Generators/C/NAPI/NAPISources.cs

@@ -0,0 +1,23 @@
+using System.Collections.Generic;
+using CppSharp.AST;
+
+namespace CppSharp.Generators.Cpp
+{
+    /// <summary>
+    /// Generates Node N-API C/C++ source files.
+    /// N-API documentation: https://nodejs.org/api/n-api.html
+    /// </summary>
+    public class NAPISources : CppSources
+    {
+        public NAPISources(BindingContext context, IEnumerable<TranslationUnit> units)
+            : base(context, units)
+        {
+            CTypePrinter.PushContext(TypePrinterContextKind.Managed);
+        }
+
+        public override void Process()
+        {
+            base.Process();
+        }
+    }
+}

src/Generator/Passes/CheckDuplicatedNamesPass.cs

@@ -219,6 +219,7 @@ private TypePrinter GetTypePrinter(GeneratorKind kind, BindingContext context)
                     break;
                 case GeneratorKind.CPlusPlus:
                 case GeneratorKind.QuickJS:
+                case GeneratorKind.NAPI:
                     typePrinter = new CppTypePrinter(Context);
                     break;
                 case GeneratorKind.CLI: