//===-- AppleDWARFIndex.cpp ------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "Plugins/SymbolFile/DWARF/AppleDWARFIndex.h"
#include "Plugins/SymbolFile/DWARF/DWARFDebugInfo.h"
#include "Plugins/SymbolFile/DWARF/DWARFDeclContext.h"
#include "Plugins/SymbolFile/DWARF/DWARFUnit.h"
#include "Plugins/SymbolFile/DWARF/LogChannelDWARF.h"

#include "Plugins/Language/CPlusPlus/CPlusPlusLanguage.h"
#include "Plugins/Language/ObjC/ObjCLanguage.h"
#include "lldb/Core/Module.h"
#include "lldb/Symbol/Function.h"

using namespace lldb_private;
using namespace lldb;

std::unique_ptr<AppleDWARFIndex> AppleDWARFIndex::Create(
    Module &module, DWARFDataExtractor apple_names,
    DWARFDataExtractor apple_namespaces, DWARFDataExtractor apple_types,
    DWARFDataExtractor apple_objc, DWARFDataExtractor debug_str) {
  auto apple_names_table_up = llvm::make_unique<DWARFMappedHash::MemoryTable>(
      apple_names, debug_str, ".apple_names");
  if (!apple_names_table_up->IsValid())
    apple_names_table_up.reset();

  auto apple_namespaces_table_up =
      llvm::make_unique<DWARFMappedHash::MemoryTable>(
          apple_namespaces, debug_str, ".apple_namespaces");
  if (!apple_namespaces_table_up->IsValid())
    apple_namespaces_table_up.reset();

  auto apple_types_table_up = llvm::make_unique<DWARFMappedHash::MemoryTable>(
      apple_types, debug_str, ".apple_types");
  if (!apple_types_table_up->IsValid())
    apple_types_table_up.reset();

  auto apple_objc_table_up = llvm::make_unique<DWARFMappedHash::MemoryTable>(
      apple_objc, debug_str, ".apple_objc");
  if (!apple_objc_table_up->IsValid())
    apple_objc_table_up.reset();

  if (apple_names_table_up || apple_names_table_up || apple_types_table_up ||
      apple_objc_table_up)
    return llvm::make_unique<AppleDWARFIndex>(
        module, std::move(apple_names_table_up),
        std::move(apple_namespaces_table_up), std::move(apple_types_table_up),
        std::move(apple_objc_table_up));

  return nullptr;
}

void AppleDWARFIndex::GetGlobalVariables(ConstString name, DIEArray &offsets) {
  if (!m_apple_names_up)
    return;

  const char *name_cstr = name.GetCString();
  llvm::StringRef basename;
  llvm::StringRef context;

  if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name_cstr, context,
                                                      basename))
    basename = name_cstr;

  m_apple_names_up->FindByName(basename, offsets);
}

void AppleDWARFIndex::GetGlobalVariables(const RegularExpression &regex,
                                         DIEArray &offsets) {
  if (!m_apple_names_up)
    return;

  DWARFMappedHash::DIEInfoArray hash_data;
  if (m_apple_names_up->AppendAllDIEsThatMatchingRegex(regex, hash_data))
    DWARFMappedHash::ExtractDIEArray(hash_data, offsets);
}

void AppleDWARFIndex::GetGlobalVariables(const DWARFUnit &cu,
                                         DIEArray &offsets) {
  if (!m_apple_names_up)
    return;

  DWARFMappedHash::DIEInfoArray hash_data;
  if (m_apple_names_up->AppendAllDIEsInRange(
          cu.GetOffset(), cu.GetNextCompileUnitOffset(), hash_data))
    DWARFMappedHash::ExtractDIEArray(hash_data, offsets);
}

void AppleDWARFIndex::GetObjCMethods(ConstString class_name,
                                     DIEArray &offsets) {
  if (m_apple_objc_up)
    m_apple_objc_up->FindByName(class_name.GetStringRef(), offsets);
}

void AppleDWARFIndex::GetCompleteObjCClass(ConstString class_name,
                                           bool must_be_implementation,
                                           DIEArray &offsets) {
  if (m_apple_types_up) {
    m_apple_types_up->FindCompleteObjCClassByName(
        class_name.GetStringRef(), offsets, must_be_implementation);
  }
}

void AppleDWARFIndex::GetTypes(ConstString name, DIEArray &offsets) {
  if (m_apple_types_up)
    m_apple_types_up->FindByName(name.GetStringRef(), offsets);
}

void AppleDWARFIndex::GetTypes(const DWARFDeclContext &context,
                               DIEArray &offsets) {
  if (!m_apple_types_up)
    return;

  Log *log = LogChannelDWARF::GetLogIfAny(DWARF_LOG_TYPE_COMPLETION |
                                          DWARF_LOG_LOOKUPS);
  const bool has_tag = m_apple_types_up->GetHeader().header_data.ContainsAtom(
      DWARFMappedHash::eAtomTypeTag);
  const bool has_qualified_name_hash =
      m_apple_types_up->GetHeader().header_data.ContainsAtom(
          DWARFMappedHash::eAtomTypeQualNameHash);
  const ConstString type_name(context[0].name);
  const dw_tag_t tag = context[0].tag;
  if (has_tag && has_qualified_name_hash) {
    const char *qualified_name = context.GetQualifiedName();
    const uint32_t qualified_name_hash = llvm::djbHash(qualified_name);
    if (log)
      m_module.LogMessage(log, "FindByNameAndTagAndQualifiedNameHash()");
    m_apple_types_up->FindByNameAndTagAndQualifiedNameHash(
        type_name.GetStringRef(), tag, qualified_name_hash, offsets);
  } else if (has_tag) {
    if (log)
      m_module.LogMessage(log, "FindByNameAndTag()");
    m_apple_types_up->FindByNameAndTag(type_name.GetStringRef(), tag, offsets);
  } else
    m_apple_types_up->FindByName(type_name.GetStringRef(), offsets);
}

void AppleDWARFIndex::GetNamespaces(ConstString name, DIEArray &offsets) {
  if (m_apple_namespaces_up)
    m_apple_namespaces_up->FindByName(name.GetStringRef(), offsets);
}

static bool KeepFunctionDIE(DWARFDIE die, uint32_t name_type_mask) {
  bool looking_for_methods = name_type_mask & eFunctionNameTypeMethod;
  bool looking_for_functions = name_type_mask & eFunctionNameTypeBase;
  if (looking_for_methods && looking_for_functions)
    return true;
  return looking_for_methods == die.IsMethod();
}

void AppleDWARFIndex::GetFunctions(
    ConstString name, DWARFDebugInfo &info,
    llvm::function_ref<bool(const DWARFDIE &die, bool include_inlines,
                            lldb_private::SymbolContextList &sc_list)>
        resolve_function,
    llvm::function_ref<CompilerDeclContext(lldb::user_id_t type_uid)>
        get_decl_context_containing_uid,
    const CompilerDeclContext *parent_decl_ctx, uint32_t name_type_mask,
    bool include_inlines, SymbolContextList &sc_list) {
  if (!m_apple_names_up)
    return;

  std::set<const DWARFDebugInfoEntry *> resolved_dies;
  DIEArray offsets;

  uint32_t num_matches = 0;

  if (name_type_mask & eFunctionNameTypeFull) {
    // If they asked for the full name, match what they typed.  At some
    // point we may want to canonicalize this (strip double spaces, etc.
    // For now, we just add all the dies that we find by exact match.
    num_matches = m_apple_names_up->FindByName(name.GetStringRef(), offsets);
    for (uint32_t i = 0; i < num_matches; i++) {
      const DIERef &die_ref = offsets[i];
      DWARFDIE die = info.GetDIE(die_ref);
      if (die) {
        if (!SymbolFileDWARF::DIEInDeclContext(parent_decl_ctx, die))
          continue; // The containing decl contexts don't match

        if (resolved_dies.find(die.GetDIE()) == resolved_dies.end()) {
          if (resolve_function(die, include_inlines, sc_list))
            resolved_dies.insert(die.GetDIE());
        }
      } else
        ReportInvalidDIEOffset(die_ref.die_offset, name.GetStringRef());
    }
  }

  if (name_type_mask & eFunctionNameTypeSelector) {
    if (parent_decl_ctx && parent_decl_ctx->IsValid())
      return; // no selectors in namespaces

    num_matches = m_apple_names_up->FindByName(name.GetStringRef(), offsets);
    // Now make sure these are actually ObjC methods.  In this case we can
    // simply look up the name, and if it is an ObjC method name, we're
    // good.

    for (uint32_t i = 0; i < num_matches; i++) {
      const DIERef &die_ref = offsets[i];
      DWARFDIE die = info.GetDIE(die_ref);
      if (die) {
        const char *die_name = die.GetName();
        if (ObjCLanguage::IsPossibleObjCMethodName(die_name)) {
          if (resolved_dies.find(die.GetDIE()) == resolved_dies.end()) {
            if (resolve_function(die, include_inlines, sc_list))
              resolved_dies.insert(die.GetDIE());
          }
        }
      } else
        ReportInvalidDIEOffset(die_ref.die_offset, name.GetStringRef());
    }
    offsets.clear();
  }

  if (((name_type_mask & eFunctionNameTypeMethod) && !parent_decl_ctx) ||
      name_type_mask & eFunctionNameTypeBase) {
    // The apple_names table stores just the "base name" of C++ methods in
    // the table.  So we have to extract the base name, look that up, and
    // if there is any other information in the name we were passed in we
    // have to post-filter based on that.

    // FIXME: Arrange the logic above so that we don't calculate the base
    // name twice:
    num_matches = m_apple_names_up->FindByName(name.GetStringRef(), offsets);

    for (uint32_t i = 0; i < num_matches; i++) {
      const DIERef &die_ref = offsets[i];
      DWARFDIE die = info.GetDIE(die_ref);
      if (die) {
        if (!SymbolFileDWARF::DIEInDeclContext(parent_decl_ctx, die))
          continue; // The containing decl contexts don't match

        if (!KeepFunctionDIE(die, name_type_mask))
          continue;

        if (resolved_dies.find(die.GetDIE()) != resolved_dies.end())
          continue;

        // If we get to here, the die is good, and we should add it:
        if (resolve_function(die, include_inlines, sc_list))
          resolved_dies.insert(die.GetDIE());
      } else
        ReportInvalidDIEOffset(die_ref.die_offset, name.GetStringRef());
    }
    offsets.clear();
  }
}

void AppleDWARFIndex::GetFunctions(
    const RegularExpression &regex, DWARFDebugInfo &info,
    llvm::function_ref<bool(const DWARFDIE &die, bool include_inlines,
                            lldb_private::SymbolContextList &sc_list)>
        resolve_function,
    bool include_inlines, SymbolContextList &sc_list) {
  if (!m_apple_names_up)
    return;

  DIEArray offsets;
  DWARFMappedHash::DIEInfoArray hash_data;
  if (m_apple_names_up->AppendAllDIEsThatMatchingRegex(regex, hash_data)) {
    DWARFMappedHash::ExtractDIEArray(hash_data, offsets);
    ParseFunctions(offsets, info, resolve_function, include_inlines, sc_list);
  }
}

void AppleDWARFIndex::ReportInvalidDIEOffset(dw_offset_t offset,
                                             llvm::StringRef name) {
  m_module.ReportErrorIfModifyDetected(
      "the DWARF debug information has been modified (accelerator table had "
      "bad die 0x%8.8x for '%s')\n",
      offset, name.str().c_str());
}

void AppleDWARFIndex::Dump(Stream &s) {
  // TODO: Implement dumping.
}