Caa/src/Binding.bf

namespace Caa;

using System;
using System.Collections;
using libclang_beef;

class Binding
{
	public static List<BindingFunction> Function = new .() ~ DeleteContainerAndItems!(_);
	public static List<BindingEnum> Enums = new .() ~ DeleteContainerAndItems!(_);
	public static List<BindingStruct> Structs = new .() ~ DeleteContainerAndItems!(_);
	public static BindingOptions Options = new .() ~ delete _;
	public static Dictionary<CXCursorKind, function void(CXCursor*)> CursorHandlers = new .() {
		(.CXCursor_FunctionDecl, => HandleFunctionDecl),
		(.CXCursor_StructDecl, => HandleStructDecl),
		(.CXCursor_FieldDecl, => HandleFieldDecl),
		(.CXCursor_EnumDecl, => HandleEnumDecl),
		(.CXCursor_EnumConstantDecl, => HandleEnumConstDecl),
		(.CXCursor_ParmDecl, => DoNothing),



	} ~ delete _;

	public static void Bind(ref String[] pArgs)
	{
		CXIndex index = clang_createIndex(0, 0);
		CXTranslationUnit* unit;
		clang_parseTranslationUnit2(
			index,
			pArgs[0], //TODO: This is a hack, allegedly it would be fine if we just input the file as an arg but that doesnt seem to work
			(.)&pArgs, (.)pArgs.Count, null, 0,
			(.)CXTranslationUnit_Flags.CXTranslationUnit_None,
			out unit
			);
		//TODO: Error Handling

		CXCursor cursor = clang_getTranslationUnitCursor(*unit);
		clang_visitChildren(
			cursor,
			(cursor, parent, client_data) => {

				switch(clang_getCursorKind(cursor))
				{
				case .CXCursor_FunctionDecl:
					var name = clang_getCursorSpelling(cursor);
					BindingFunction func = new .(name.text, clang_getCursorResultType(cursor));
					var count = clang_Cursor_getNumArguments(cursor);
					for(int i < count)
					{
						var arg = clang_Cursor_getArgument(cursor, (.)i);
						var argType = clang_getCursorType(arg);
						var argName = clang_getCursorSpelling(arg);
						func.Args.Add(new .(argName.text, argType));
					}	
					Function.Add(func);
				case .CXCursor_StructDecl:
					var name = clang_getCursorSpelling(cursor);
					BindingStruct strct = new .(name.text);
					Structs.Add(strct);
				case .CXCursor_FieldDecl:
					if(Structs.Count > 0)
						Structs[Structs.Count-1].Fields.Add(new .(clang_getCursorSpelling(cursor).text, clang_getCursorType(cursor)));
				case .CXCursor_EnumDecl:
					var name = clang_getCursorSpelling(cursor);
					BindingEnum enm = new .(name.text);
					Enums.Add(enm);
				case .CXCursor_EnumConstantDecl:
					if(Enums.Count > 0)
						Enums[Enums.Count-1].Entries.Add(new .(clang_getCursorSpelling(cursor).text, (.)clang_getEnumConstantDeclValue(cursor)));
				case .CXCursor_ParmDecl:
						DoNothing(&cursor);
				default:
					Console.WriteLine(scope $"{clang_getCursorKind(cursor)} {clang_getCursorSpelling(cursor).text}");
				}

				/*
				if(CursorHandlers.ContainsKey(clang_getCursorKind(cursor)))
					CursorHandlers[clang_getCursorKind(cursor)](&cursor);
				else
					Console.WriteLine(scope $"{clang_getCursorKind(cursor)} {clang_getCursorSpelling(cursor).text}");
				*/


				return CXChildVisitResult.CXChildVisit_Recurse;
			}, null );


		clang_disposeTranslationUnit(*unit);
		clang_disposeIndex(index);
	}

	public static void HandleFunctionDecl(CXCursor* cursor)
	{
		var name = clang_getCursorSpelling(*cursor);
		BindingFunction func = new .(name.text, clang_getCursorResultType(*cursor));

		var count = clang_Cursor_getNumArguments(*cursor);
		for(int i < count)
		{
			var arg = clang_Cursor_getArgument(*cursor, (.)i);
			var argType = clang_getCursorType(arg);
			var argName = clang_getCursorSpelling(arg);
			func.Args.Add(new .(argName.text, argType));
		}	
		Function.Add(func);
	}

	public static void HandleStructDecl(CXCursor* cursor)
	{
		var name = clang_getCursorSpelling(*cursor);
		BindingStruct strct = new .(name.text);
		Structs.Add(strct);
	}

	public static void HandleFieldDecl(CXCursor* cursor)
	{
		if(Structs.Count > 0)
			Structs[Structs.Count-1].Fields.Add(new .(clang_getCursorSpelling(*cursor).text, clang_getCursorType(*cursor)));
	}

	public static void HandleEnumDecl(CXCursor* cursor)
	{
		var name = clang_getCursorSpelling(*cursor);
		BindingEnum enm = new .(name.text);
		Enums.Add(enm);
	}

	public static void HandleEnumConstDecl(CXCursor* cursor)
	{
		if(Enums.Count > 0)
		{
			Enums[Enums.Count-1].Entries.Add(new .(clang_getCursorSpelling(*cursor).text, (.)clang_getEnumConstantDeclValue(*cursor)));
		}
	}

	private static void DoNothing(CXCursor* cursor) {}


	///Generate the actual file strings and try to write them according to the input parameter and the options
	public static Result<void> Generate(StringView pOutputDir = "")
	{
		if(pOutputDir == "")
			return .Err;

		String toWrite = new .(scope $"""
			namespace {Binding.Options.Namespace};
			static
			\{\n
			""");
		defer delete toWrite;

		for(var i in Function)
			i.ToBeef(toWrite);
		for(var i in Structs)
			i.ToBeef(toWrite);
		for(var i in Enums)
			i.ToBeef(toWrite);
		toWrite.Append("\n}");

		return System.IO.File.WriteAllText(pOutputDir, toWrite);
	}


}