//===--- ObjectFile.h - Object File Related Information ------*- C++ -*-===//
//
// Object File related data structures.
//
//===----------------------------------------------------------------------===//

#ifndef SWIFT_ABI_OBJECTFILE_H
#define SWIFT_ABI_OBJECTFILE_H

#include "llvm/ADT/StringRef.h"
#include "llvm/Support/ErrorHandling.h"
#include <optional>

namespace swift {

/// Represents the nine reflection sections used by Swift + the Swift AST
/// section used by the debugger.
enum ReflectionSectionKind : uint8_t {
#define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF) KIND,
#include "llvm/BinaryFormat/Swift.def"
#undef HANDLE_SWIFT_SECTION
};

/// Abstract base class responsible for providing the correct reflection section
/// string identifier for a given object file type (Mach-O, ELF, COFF).
class SwiftObjectFileFormat {
public:
  virtual ~SwiftObjectFileFormat() {}
  virtual llvm::StringRef getSectionName(ReflectionSectionKind section) = 0;
  virtual std::optional<llvm::StringRef> getSegmentName() { return {}; }
  /// Get the name of the segment in the symbol rich binary that may contain
  /// Swift metadata.
  virtual std::optional<llvm::StringRef> getSymbolRichSegmentName() {
    return {};
  }
  /// Predicate to identify if the named section can contain reflection data.
  virtual bool sectionContainsReflectionData(llvm::StringRef sectionName) = 0;
};

/// Responsible for providing the Mach-O reflection section identifiers.
class SwiftObjectFileFormatMachO : public SwiftObjectFileFormat {
public:
  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
    switch (section) {
#define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF)                           \
  case KIND:                                                                   \
    return MACHO;
#include "llvm/BinaryFormat/Swift.def"
#undef HANDLE_SWIFT_SECTION
    }
    llvm_unreachable("Section type not found.");
  }

  std::optional<llvm::StringRef> getSegmentName() override {
    return {"__TEXT"};
  }

  std::optional<llvm::StringRef> getSymbolRichSegmentName() override {
    return {"__DWARF"};
  }

  bool sectionContainsReflectionData(llvm::StringRef sectionName) override {
    return sectionName.starts_with("__swift5_") || sectionName == "__const";
  }
};

/// Responsible for providing the ELF reflection section identifiers.
class SwiftObjectFileFormatELF : public SwiftObjectFileFormat {
public:
  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
    switch (section) {
#define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF)                           \
  case KIND:                                                                   \
    return ELF;
#include "llvm/BinaryFormat/Swift.def"
#undef HANDLE_SWIFT_SECTION
    }
    llvm_unreachable("Section type not found.");
  }

  bool sectionContainsReflectionData(llvm::StringRef sectionName) override {
    return sectionName.starts_with("swift5_");
  }
};

/// Responsible for providing the COFF reflection section identifiers.
class SwiftObjectFileFormatCOFF : public SwiftObjectFileFormat {
public:
  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
    switch (section) {
#define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF)                           \
  case KIND:                                                                   \
    return COFF;
#include "llvm/BinaryFormat/Swift.def"
#undef HANDLE_SWIFT_SECTION
    }
    llvm_unreachable("Section  not found.");
  }

  bool sectionContainsReflectionData(llvm::StringRef sectionName) override {
    return sectionName.starts_with(".sw5");
  }
};

/// Responsible for providing the WebAssembly reflection section identifiers.
/// WebAssembly binaries store all reflection metadata in the DATA
/// section. There are symbols for each reflection section kind in the "name"
/// section that point to the corresponding offset inside DATA.
class SwiftObjectFileFormatWasm : public SwiftObjectFileFormat {
public:
  llvm::StringRef getSectionName(ReflectionSectionKind section) override {
    switch (section) {
#define HANDLE_SWIFT_SECTION(KIND, MACHO, ELF, COFF)                           \
  case KIND:                                                                   \
    return ELF;
#include "llvm/BinaryFormat/Swift.def"
#undef HANDLE_SWIFT_SECTION
    }
    llvm_unreachable("Section  not found.");
  }

  bool sectionContainsReflectionData(llvm::StringRef sectionName) override {
    return sectionName.starts_with("swift5_");
  }
};

} // namespace swift
#endif // SWIFT_ABI_OBJECTFILE_H