1 files changed, 138 insertions, 0 deletions
diff --git a/src/CompilerKit/Frontend.h b/src/CompilerKit/Frontend.h
new file mode 100644
index 0000000..df70048
--- /dev/null
+++ b/src/CompilerKit/Frontend.h
@@ -0,0 +1,138 @@
+/* ========================================
+
+  Copyright (C) 2024-2025 Amlal El Mahrouss, Licensed under the Apache 2.0 license
+
+======================================== */
+
+#pragma once
+
+#include <CompilerKit/Compiler.h>
+
+#define CK_COMPILER_FRONTEND : public ::CompilerKit::CompilerFrontendInterface
+
+namespace CompilerKit {
+inline static auto kInvalidFrontend = "(null)";
+
+struct SyntaxLeafList;
+struct SyntaxLeafList;
+struct CompilerKeyword;
+
+/// =========================================================== ///
+/// @note we want to do that to separate keywords.
+/// =========================================================== ///
+
+enum KeywordKind {
+  kKeywordKindNamespace,
+  kKeywordKindFunctionStart,
+  kKeywordKindFunctionEnd,
+  kKeywordKindVariable,
+  kKeywordKindVariablePtr,
+  kKeywordKindType,
+  kKeywordKindTypePtr,
+  kKeywordKindExpressionBegin,
+  kKeywordKindExpressionEnd,
+  kKeywordKindArgSeparator,
+  kKeywordKindBodyStart,
+  kKeywordKindBodyEnd,
+  kKeywordKindClass,
+  kKeywordKindPtrAccess,
+  kKeywordKindAccess,
+  kKeywordKindIf,
+  kKeywordKindElse,
+  kKeywordKindElseIf,
+  kKeywordKindVariableAssign,
+  kKeywordKindVariableDec,
+  kKeywordKindVariableInc,
+  kKeywordKindConstant,
+  kKeywordKindTypedef,
+  kKeywordKindEndInstr,
+  kKeywordKindSpecifier,
+  kKeywordKindInvalid,
+  kKeywordKindReturn,
+  kKeywordKindCommentInline,
+  kKeywordKindCommentMultiLineStart,
+  kKeywordKindCommentMultiLineEnd,
+  kKeywordKindEq,
+  kKeywordKindNotEq,
+  kKeywordKindGreaterEq,
+  kKeywordKindLessEq,
+  kKeywordKindPtr,
+};
+
+/// =========================================================== ///
+/// \brief Compiler keyword information struct.
+/// =========================================================== ///
+struct CompilerKeyword {
+  CompilerKeyword(STLString name, KeywordKind kind) : keyword_name(name), keyword_kind(kind) {}
+
+  STLString   keyword_name{""};
+  KeywordKind keyword_kind{kKeywordKindInvalid};
+};
+
+struct SyntaxLeafList final {
+  struct SyntaxLeaf final {
+    Int32           fUserType{0U};
+    CompilerKeyword fUserData{"", kKeywordKindInvalid};
+
+    STLString          fUserValue{""};
+    struct SyntaxLeaf* fNext{nullptr};
+  };
+
+  std::vector<SyntaxLeaf> fLeafList;
+  SizeType                fNumLeafs{0};
+
+  SizeType                 SizeOf() { return fNumLeafs; }
+  std::vector<SyntaxLeaf>& Get() { return fLeafList; }
+  SyntaxLeaf&              At(SizeType index) { return fLeafList[index]; }
+};
+
+/// =========================================================== ///
+/// find the perfect matching word in a haystack.
+/// \param haystack base string
+/// \param needle the string we search for.
+/// \return if we found it or not.
+/// =========================================================== ///
+Bool find_word(STLString haystack, STLString needle) noexcept;
+
+/// =========================================================== ///
+/// find a word within strict conditions and returns a range of it.
+/// \param haystack
+/// \param needle
+/// \return position of needle.
+/// =========================================================== ///
+SizeType find_word_range(STLString haystack, STLString needle) noexcept;
+
+/// =========================================================== ///
+/// @brief Compiler backend, implements a frontend, such as C, C++...
+/// See Toolchain, for some examples.
+/// =========================================================== ///
+class CompilerFrontendInterface {
+ public:
+  explicit CompilerFrontendInterface() = default;
+  virtual ~CompilerFrontendInterface() = default;
+
+  NECTI_COPY_DEFAULT(CompilerFrontendInterface);
+
+  /// =========================================================== ///
+  // NOTE: cast this to your user defined ast.
+  /// =========================================================== ///
+  typedef VoidPtr AstType;
+
+  /// =========================================================== ///
+  //! @brief Compile a syntax tree ouf of the text.
+  //! Also takes the source file name for metadata.
+  /// =========================================================== ///
+
+  virtual CompilerKit::SyntaxLeafList::SyntaxLeaf Compile(std::string text, std::string file) = 0;
+
+  /// =========================================================== ///
+  //! @brief What language are we dealing with?
+  /// =========================================================== ///
+  virtual const char* Language() { return kInvalidFrontend; }
+
+  /// =========================================================== ///
+  /// @brief Checks if language is a valid frontend.
+  /// =========================================================== ///
+  virtual bool IsValid() { return strcmp(this->Language(), kInvalidFrontend) > 0; }
+};
+}  // namespace CompilerKit