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

#include "DWARFASTParserJava.h"
#include "DWARFAttribute.h"
#include "DWARFCompileUnit.h"
#include "DWARFDebugInfoEntry.h"
#include "DWARFDebugInfoEntry.h"
#include "DWARFDeclContext.h"
#include "SymbolFileDWARF.h"

#include "lldb/Core/Module.h"
#include "lldb/Symbol/CompileUnit.h"
#include "lldb/Symbol/SymbolContextScope.h"
#include "lldb/Symbol/TypeList.h"

using namespace lldb;
using namespace lldb_private;

DWARFASTParserJava::DWARFASTParserJava(JavaASTContext &ast) : m_ast(ast)
{
}

DWARFASTParserJava::~DWARFASTParserJava()
{
}

TypeSP
DWARFASTParserJava::ParseBaseTypeFromDIE(const DWARFDIE &die)
{
    SymbolFileDWARF *dwarf = die.GetDWARF();
    dwarf->m_die_to_type[die.GetDIE()] = DIE_IS_BEING_PARSED;

    ConstString type_name;
    uint64_t byte_size = 0;

    DWARFAttributes attributes;
    const size_t num_attributes = die.GetAttributes(attributes);
    for (uint32_t i = 0; i < num_attributes; ++i)
    {
        DWARFFormValue form_value;
        dw_attr_t attr = attributes.AttributeAtIndex(i);
        if (attributes.ExtractFormValueAtIndex(i, form_value))
        {
            switch (attr)
            {
                case DW_AT_name:
                    type_name.SetCString(form_value.AsCString());
                    break;
                case DW_AT_byte_size:
                    byte_size = form_value.Unsigned();
                    break;
                case DW_AT_encoding:
                    break;
                default:
                    assert(false && "Unsupported attribute for DW_TAG_base_type");
            }
        }
    }

    Declaration decl;
    CompilerType compiler_type = m_ast.CreateBaseType(type_name);
    return std::make_shared<Type>(die.GetID(), dwarf, type_name, byte_size, nullptr, LLDB_INVALID_UID,
                                  Type::eEncodingIsUID, decl, compiler_type, Type::eResolveStateFull);
}

TypeSP
DWARFASTParserJava::ParseArrayTypeFromDIE(const DWARFDIE &die)
{
    SymbolFileDWARF *dwarf = die.GetDWARF();
    dwarf->m_die_to_type[die.GetDIE()] = DIE_IS_BEING_PARSED;

    ConstString linkage_name;
    DWARFFormValue type_attr_value;
    lldb::addr_t data_offset = LLDB_INVALID_ADDRESS;
    DWARFExpression length_expression(die.GetCU());

    DWARFAttributes attributes;
    const size_t num_attributes = die.GetAttributes(attributes);
    for (uint32_t i = 0; i < num_attributes; ++i)
    {
        DWARFFormValue form_value;
        dw_attr_t attr = attributes.AttributeAtIndex(i);
        if (attributes.ExtractFormValueAtIndex(i, form_value))
        {
            switch (attr)
            {
                case DW_AT_linkage_name:
                    linkage_name.SetCString(form_value.AsCString());
                    break;
                case DW_AT_type:
                    type_attr_value = form_value;
                    break;
                case DW_AT_data_member_location:
                    data_offset = form_value.Unsigned();
                    break;
                case DW_AT_declaration:
                    break;
                default:
                    assert(false && "Unsupported attribute for DW_TAG_array_type");
            }
        }
    }

    for (DWARFDIE child_die = die.GetFirstChild(); child_die.IsValid(); child_die = child_die.GetSibling())
    {
        if (child_die.Tag() == DW_TAG_subrange_type)
        {
            DWARFAttributes attributes;
            const size_t num_attributes = child_die.GetAttributes(attributes);
            for (uint32_t i = 0; i < num_attributes; ++i)
            {
                DWARFFormValue form_value;
                dw_attr_t attr = attributes.AttributeAtIndex(i);
                if (attributes.ExtractFormValueAtIndex(i, form_value))
                {
                    switch (attr)
                    {
                        case DW_AT_count:
                            if (form_value.BlockData())
                                length_expression.CopyOpcodeData(form_value.BlockData(), form_value.Unsigned(),
                                                                 child_die.GetCU()->GetByteOrder(),
                                                                 child_die.GetCU()->GetAddressByteSize());
                            break;
                        default:
                            assert(false && "Unsupported attribute for DW_TAG_subrange_type");
                    }
                }
            }
        }
        else
        {
            assert(false && "Unsupported child for DW_TAG_array_type");
        }
    }

    DIERef type_die_ref(type_attr_value);
    Type *element_type = dwarf->ResolveTypeUID(type_die_ref);
    if (!element_type)
        return nullptr;

    CompilerType element_compiler_type = element_type->GetForwardCompilerType();
    CompilerType array_compiler_type =
        m_ast.CreateArrayType(linkage_name, element_compiler_type, length_expression, data_offset);

    Declaration decl;
    TypeSP type_sp(new Type(die.GetID(), dwarf, array_compiler_type.GetTypeName(), -1, nullptr,
                            type_die_ref.GetUID(dwarf), Type::eEncodingIsUID, &decl,
                            array_compiler_type, Type::eResolveStateFull));
    type_sp->SetEncodingType(element_type);
    return type_sp;
}

TypeSP
DWARFASTParserJava::ParseReferenceTypeFromDIE(const DWARFDIE &die)
{
    SymbolFileDWARF *dwarf = die.GetDWARF();
    dwarf->m_die_to_type[die.GetDIE()] = DIE_IS_BEING_PARSED;

    Declaration decl;
    DWARFFormValue type_attr_value;

    DWARFAttributes attributes;
    const size_t num_attributes = die.GetAttributes(attributes);
    for (uint32_t i = 0; i < num_attributes; ++i)
    {
        DWARFFormValue form_value;
        dw_attr_t attr = attributes.AttributeAtIndex(i);
        if (attributes.ExtractFormValueAtIndex(i, form_value))
        {
            switch (attr)
            {
                case DW_AT_type:
                    type_attr_value = form_value;
                    break;
                default:
                    assert(false && "Unsupported attribute for DW_TAG_array_type");
            }
        }
    }

    DIERef type_die_ref(type_attr_value);
    Type *pointee_type = dwarf->ResolveTypeUID(type_die_ref);
    if (!pointee_type)
        return nullptr;

    CompilerType pointee_compiler_type = pointee_type->GetForwardCompilerType();
    CompilerType reference_compiler_type = m_ast.CreateReferenceType(pointee_compiler_type);
    TypeSP type_sp(new Type(die.GetID(), dwarf, reference_compiler_type.GetTypeName(), -1, nullptr,
                            type_die_ref.GetUID(dwarf), Type::eEncodingIsUID, &decl,
                            reference_compiler_type, Type::eResolveStateFull));
    type_sp->SetEncodingType(pointee_type);
    return type_sp;
}

lldb::TypeSP
DWARFASTParserJava::ParseClassTypeFromDIE(const DWARFDIE &die, bool &is_new_type)
{
    SymbolFileDWARF *dwarf = die.GetDWARF();
    dwarf->m_die_to_type[die.GetDIE()] = DIE_IS_BEING_PARSED;

    Declaration decl;
    ConstString name;
    ConstString linkage_name;
    bool is_forward_declaration = false;
    uint32_t byte_size = 0;

    DWARFAttributes attributes;
    const size_t num_attributes = die.GetAttributes(attributes);
    for (uint32_t i = 0; i < num_attributes; ++i)
    {
        DWARFFormValue form_value;
        dw_attr_t attr = attributes.AttributeAtIndex(i);
        if (attributes.ExtractFormValueAtIndex(i, form_value))
        {
            switch (attr)
            {
                case DW_AT_name:
                    name.SetCString(form_value.AsCString());
                    break;
                case DW_AT_declaration:
                    is_forward_declaration = form_value.Boolean();
                    break;
                case DW_AT_byte_size:
                    byte_size = form_value.Unsigned();
                    break;
                case DW_AT_linkage_name:
                    linkage_name.SetCString(form_value.AsCString());
                    break;
                default:
                    assert(false && "Unsupported attribute for DW_TAG_class_type");
            }
        }
    }

    UniqueDWARFASTType unique_ast_entry;
    if (name)
    {
        std::string qualified_name;
        if (die.GetQualifiedName(qualified_name))
        {
            name.SetCString(qualified_name.c_str());
            if (dwarf->GetUniqueDWARFASTTypeMap().Find(name, die, Declaration(), -1, unique_ast_entry))
            {
                if (unique_ast_entry.m_type_sp)
                {
                    dwarf->GetDIEToType()[die.GetDIE()] = unique_ast_entry.m_type_sp.get();
                    is_new_type = false;
                    return unique_ast_entry.m_type_sp;
                }
            }
        }
    }

    if (is_forward_declaration)
    {
        DWARFDeclContext die_decl_ctx;
        die.GetDWARFDeclContext(die_decl_ctx);

        TypeSP type_sp = dwarf->FindDefinitionTypeForDWARFDeclContext(die_decl_ctx);
        if (type_sp)
        {
            // We found a real definition for this type elsewhere so lets use it
            dwarf->GetDIEToType()[die.GetDIE()] = type_sp.get();
            is_new_type = false;
            return type_sp;
        }
    }

    CompilerType compiler_type(&m_ast, dwarf->GetForwardDeclDieToClangType().lookup(die.GetDIE()));
    if (!compiler_type)
        compiler_type = m_ast.CreateObjectType(name, linkage_name, byte_size);

    is_new_type = true;
    TypeSP type_sp(new Type(die.GetID(), dwarf, name,
                            -1, // byte size isn't specified
                            nullptr, LLDB_INVALID_UID, Type::eEncodingIsUID, &decl, compiler_type,
                            Type::eResolveStateForward));

    // Add our type to the unique type map
    unique_ast_entry.m_type_sp = type_sp;
    unique_ast_entry.m_die = die;
    unique_ast_entry.m_declaration = decl;
    unique_ast_entry.m_byte_size = -1;
    dwarf->GetUniqueDWARFASTTypeMap().Insert(name, unique_ast_entry);

    if (!is_forward_declaration)
    {
        // Leave this as a forward declaration until we need to know the details of the type
        dwarf->GetForwardDeclDieToClangType()[die.GetDIE()] = compiler_type.GetOpaqueQualType();
        dwarf->GetForwardDeclClangTypeToDie()[compiler_type.GetOpaqueQualType()] = die.GetDIERef();
    }
    return type_sp;
}

lldb::TypeSP
DWARFASTParserJava::ParseTypeFromDWARF(const lldb_private::SymbolContext &sc, const DWARFDIE &die,
                                       lldb_private::Log *log, bool *type_is_new_ptr)
{
    if (type_is_new_ptr)
        *type_is_new_ptr = false;

    if (!die)
        return nullptr;

    SymbolFileDWARF *dwarf = die.GetDWARF();

    Type *type_ptr = dwarf->m_die_to_type.lookup(die.GetDIE());
    if (type_ptr == DIE_IS_BEING_PARSED)
        return nullptr;
    if (type_ptr != nullptr)
        return type_ptr->shared_from_this();

    TypeSP type_sp;
    if (type_is_new_ptr)
        *type_is_new_ptr = true;

    switch (die.Tag())
    {
        case DW_TAG_base_type:
        {
            type_sp = ParseBaseTypeFromDIE(die);
            break;
        }
        case DW_TAG_array_type:
        {
            type_sp = ParseArrayTypeFromDIE(die);
            break;
        }
        case DW_TAG_class_type:
        {
            bool is_new_type = false;
            type_sp = ParseClassTypeFromDIE(die, is_new_type);
            if (!is_new_type)
                return type_sp;
            break;
        }
        case DW_TAG_reference_type:
        {
            type_sp = ParseReferenceTypeFromDIE(die);
            break;
        }
    }

    if (!type_sp)
        return nullptr;

    DWARFDIE sc_parent_die = SymbolFileDWARF::GetParentSymbolContextDIE(die);
    dw_tag_t sc_parent_tag = sc_parent_die.Tag();

    SymbolContextScope *symbol_context_scope = nullptr;
    if (sc_parent_tag == DW_TAG_compile_unit)
    {
        symbol_context_scope = sc.comp_unit;
    }
    else if (sc.function != nullptr && sc_parent_die)
    {
        symbol_context_scope = sc.function->GetBlock(true).FindBlockByID(sc_parent_die.GetID());
        if (symbol_context_scope == nullptr)
            symbol_context_scope = sc.function;
    }

    if (symbol_context_scope != nullptr)
        type_sp->SetSymbolContextScope(symbol_context_scope);

    dwarf->GetTypeList()->Insert(type_sp);
    dwarf->m_die_to_type[die.GetDIE()] = type_sp.get();

    return type_sp;
}

lldb_private::Function *
DWARFASTParserJava::ParseFunctionFromDWARF(const lldb_private::SymbolContext &sc, const DWARFDIE &die)
{
    assert(die.Tag() == DW_TAG_subprogram);

    const char *name = nullptr;
    const char *mangled = nullptr;
    int decl_file = 0;
    int decl_line = 0;
    int decl_column = 0;
    int call_file = 0;
    int call_line = 0;
    int call_column = 0;
    DWARFRangeList func_ranges;
    DWARFExpression frame_base(die.GetCU());

    if (die.GetDIENamesAndRanges(name, mangled, func_ranges, decl_file, decl_line, decl_column, call_file, call_line,
                                 call_column, &frame_base))
    {
        // Union of all ranges in the function DIE (if the function is discontiguous)
        AddressRange func_range;
        lldb::addr_t lowest_func_addr = func_ranges.GetMinRangeBase(0);
        lldb::addr_t highest_func_addr = func_ranges.GetMaxRangeEnd(0);
        if (lowest_func_addr != LLDB_INVALID_ADDRESS && lowest_func_addr <= highest_func_addr)
        {
            ModuleSP module_sp(die.GetModule());
            func_range.GetBaseAddress().ResolveAddressUsingFileSections(lowest_func_addr, module_sp->GetSectionList());
            if (func_range.GetBaseAddress().IsValid())
                func_range.SetByteSize(highest_func_addr - lowest_func_addr);
        }

        if (func_range.GetBaseAddress().IsValid())
        {
            std::unique_ptr<Declaration> decl_ap;
            if (decl_file != 0 || decl_line != 0 || decl_column != 0)
                decl_ap.reset(new Declaration(sc.comp_unit->GetSupportFiles().GetFileSpecAtIndex(decl_file), decl_line,
                                              decl_column));

            if (die.GetDWARF()->FixupAddress(func_range.GetBaseAddress()))
            {
                FunctionSP func_sp(new Function(sc.comp_unit, die.GetID(), die.GetID(),
                                                Mangled(ConstString(name), false),
                                                nullptr, // No function types in java
                                                func_range));
                if (frame_base.IsValid())
                    func_sp->GetFrameBaseExpression() = frame_base;
                sc.comp_unit->AddFunction(func_sp);

                return func_sp.get();
            }
        }
    }
    return nullptr;
}

bool
DWARFASTParserJava::CompleteTypeFromDWARF(const DWARFDIE &die, lldb_private::Type *type,
                                          lldb_private::CompilerType &java_type)
{
    switch (die.Tag())
    {
        case DW_TAG_class_type:
            {
                if (die.GetAttributeValueAsUnsigned(DW_AT_declaration, 0) == 0)
                {
                    if (die.HasChildren())
                        ParseChildMembers(die, java_type);
                    m_ast.CompleteObjectType(java_type);
                    return java_type.IsValid();
                }
            }
            break;
        default:
            assert(false && "Not a forward java type declaration!");
            break;
    }
    return false;
}

void
DWARFASTParserJava::ParseChildMembers(const DWARFDIE &parent_die, CompilerType &compiler_type)
{
    DWARFCompileUnit *dwarf_cu = parent_die.GetCU();
    for (DWARFDIE die = parent_die.GetFirstChild(); die.IsValid(); die = die.GetSibling())
    {
        switch (die.Tag())
        {
            case DW_TAG_member:
            {
                const char *name = nullptr;
                DWARFFormValue encoding_uid;
                uint32_t member_byte_offset = UINT32_MAX;
                DWARFExpression member_location_expression(dwarf_cu);

                DWARFAttributes attributes;
                size_t num_attributes = die.GetAttributes(attributes);
                for (size_t i = 0; i < num_attributes; ++i)
                {
                    DWARFFormValue form_value;
                    if (attributes.ExtractFormValueAtIndex(i, form_value))
                    {
                        switch (attributes.AttributeAtIndex(i))
                        {
                            case DW_AT_name:
                                name = form_value.AsCString();
                                break;
                            case DW_AT_type:
                                encoding_uid = form_value;
                                break;
                            case DW_AT_data_member_location:
                                if (form_value.BlockData())
                                    member_location_expression.CopyOpcodeData(
                                        form_value.BlockData(), form_value.Unsigned(), dwarf_cu->GetByteOrder(),
                                        dwarf_cu->GetAddressByteSize());
                                else
                                    member_byte_offset = form_value.Unsigned();
                                break;
                            case DW_AT_artificial:
                                static_cast<void>(form_value.Boolean());
                                break;
                            case DW_AT_accessibility:
                                // TODO: Handle when needed
                                break;
                            default:
                                assert(false && "Unhandled attribute for DW_TAG_member");
                                break;
                        }
                    }
                }

                if (strcmp(name, ".dynamic_type") == 0)
                    m_ast.SetDynamicTypeId(compiler_type, member_location_expression);
                else
                {
                    if (Type *member_type = die.ResolveTypeUID(DIERef(encoding_uid)))
                        m_ast.AddMemberToObject(compiler_type, ConstString(name), member_type->GetFullCompilerType(),
                                                member_byte_offset);
                }
                break;
            }
            case DW_TAG_inheritance:
            {
                DWARFFormValue encoding_uid;
                uint32_t member_byte_offset = UINT32_MAX;

                DWARFAttributes attributes;
                size_t num_attributes = die.GetAttributes(attributes);
                for (size_t i = 0; i < num_attributes; ++i)
                {
                    DWARFFormValue form_value;
                    if (attributes.ExtractFormValueAtIndex(i, form_value))
                    {
                        switch (attributes.AttributeAtIndex(i))
                        {
                            case DW_AT_type:
                                encoding_uid = form_value;
                                break;
                            case DW_AT_data_member_location:
                                member_byte_offset = form_value.Unsigned();
                                break;
                            case DW_AT_accessibility:
                                // In java all base class is public so we can ignore this attribute
                                break;
                            default:
                                assert(false && "Unhandled attribute for DW_TAG_member");
                                break;
                        }
                    }
                }
                if (Type *base_type = die.ResolveTypeUID(DIERef(encoding_uid)))
                    m_ast.AddBaseClassToObject(compiler_type, base_type->GetFullCompilerType(), member_byte_offset);
                break;
            }
            default:
                break;
        }
    }
}