// Copyright (C) 2017-2018 Jonathan Müller <jonathanmueller.dev@gmail.com>
// This file is subject to the license terms in the LICENSE file
// found in the top-level directory of this distribution.

#include <cppast/cpp_class.hpp>

#include <cppast/cpp_entity_index.hpp>
#include <cppast/cpp_entity_kind.hpp>
#include <cppast/cpp_alias_template.hpp>
#include <cppast/cpp_class_template.hpp>

using namespace cppast;

std::unique_ptr<cpp_class> cpp_class::builder::finish(
    const cpp_entity_index& idx, cpp_entity_id id,
    type_safe::optional<cpp_entity_ref> semantic_parent)
{
    class_->set_semantic_parent(std::move(semantic_parent));
    idx.register_definition(std::move(id), type_safe::ref(*class_));
    return std::move(class_);
}

std::unique_ptr<cpp_class> cpp_class::builder::finish_declaration(const cpp_entity_index& idx,
                                                                  cpp_entity_id definition_id)
{
    class_->mark_declaration(definition_id);
    idx.register_forward_declaration(std::move(definition_id), type_safe::ref(*class_));
    return std::move(class_);
}

std::unique_ptr<cpp_class> cpp_class::builder::finish(
    type_safe::optional<cpp_entity_ref> semantic_parent)
{
    class_->set_semantic_parent(std::move(semantic_parent));
    return std::move(class_);
}

std::unique_ptr<cpp_class> cpp_class::builder::finish_declaration(cpp_entity_id definition_id)
{
    class_->mark_declaration(definition_id);
    return std::move(class_);
}

const char* cppast::to_string(cpp_class_kind kind) noexcept
{
    switch (kind)
    {
    case cpp_class_kind::class_t:
        return "class";
    case cpp_class_kind::struct_t:
        return "struct";
    case cpp_class_kind::union_t:
        return "union";
    }

    return "should not get here";
}

const char* cppast::to_string(cpp_access_specifier_kind access) noexcept
{
    switch (access)
    {
    case cpp_public:
        return "public";
    case cpp_protected:
        return "protected";
    case cpp_private:
        return "private";
    }

    return "should not get here either";
}

cpp_entity_kind cpp_access_specifier::kind() noexcept
{
    return cpp_entity_kind::access_specifier_t;
}

cpp_entity_kind cpp_access_specifier::do_get_entity_kind() const noexcept
{
    return kind();
}

cpp_entity_kind cpp_base_class::kind() noexcept
{
    return cpp_entity_kind::base_class_t;
}

cpp_entity_kind cpp_base_class::do_get_entity_kind() const noexcept
{
    return kind();
}

cpp_entity_kind cpp_class::kind() noexcept
{
    return cpp_entity_kind::class_t;
}

cpp_entity_kind cpp_class::do_get_entity_kind() const noexcept
{
    return kind();
}

namespace
{
    cpp_entity_ref get_type_ref(const cpp_type& type)
    {
        if (type.kind() == cpp_type_kind::user_defined_t)
        {
            auto& ref = static_cast<const cpp_user_defined_type&>(type).entity();
            return cpp_entity_ref(ref.id()[0u], ref.name());
        }
        else if (type.kind() == cpp_type_kind::template_instantiation_t)
        {
            auto& ref =
                static_cast<const cpp_template_instantiation_type&>(type).primary_template();
            return cpp_entity_ref(ref.id()[0u], ref.name());
        }

        DEBUG_ASSERT(type.kind() == cpp_type_kind::template_parameter_t
                         || type.kind() == cpp_type_kind::decltype_t
                         || type.kind() == cpp_type_kind::decltype_auto_t
                         || type.kind() == cpp_type_kind::unexposed_t,
                     detail::assert_handler{});
        return cpp_entity_ref(cpp_entity_id("<null id>"), "");
    }

    type_safe::optional_ref<const cpp_entity> get_entity_impl(const cpp_entity_index& index,
                                                              const cpp_entity_ref&   ref)
    {
        auto result = ref.get(index);
        if (result.empty())
            return nullptr;
        DEBUG_ASSERT(result.size() == 1u, detail::assert_handler{});

        auto entity = result.front();
        if (entity->kind() == cpp_class_template::kind())
            return type_safe::ref(static_cast<const cpp_class_template&>(*entity).class_());
        else if (entity->kind() == cpp_class_template_specialization::kind())
            return type_safe::ref(
                static_cast<const cpp_class_template_specialization&>(*entity).class_());
        else
            return entity;
    }

    type_safe::optional_ref<const cpp_class> get_class_impl(const cpp_entity_index& index,
                                                            const cpp_entity_ref&   ref)
    {
        auto entity = get_entity_impl(index, ref);
        if (!entity)
            return nullptr;

        if (entity.value().kind() == cpp_alias_template::kind())
        {
            auto& alias = static_cast<const cppast::cpp_alias_template&>(entity.value());
            return get_class_impl(index, get_type_ref(alias.type_alias().underlying_type()));
        }
        else if (entity.value().kind() == cpp_type_alias::kind())
        {
            auto& alias = static_cast<const cppast::cpp_type_alias&>(entity.value());
            return get_class_impl(index, get_type_ref(alias.underlying_type()));
        }
        else
        {
            DEBUG_ASSERT(entity.value().kind() == cpp_class::kind(), detail::assert_handler{});
            return type_safe::ref(static_cast<const cpp_class&>(entity.value()));
        }
    }
}

type_safe::optional_ref<const cpp_class> cppast::get_class(const cpp_entity_index& index,
                                                           const cpp_base_class&   base)
{
    return get_class_impl(index, get_type_ref(base.type()));
}

type_safe::optional_ref<const cpp_entity> cppast::get_class_or_typedef(
    const cpp_entity_index& index, const cpp_base_class& base)
{
    return get_entity_impl(index, get_type_ref(base.type()));
}