libperl-macrogen 0.1.3

//! 型表現モジュール
//!
//! TypeConstraint で使用する構造化された型表現を提供する。
//! C 型、Rust 型、推論結果を統一的に表現し、文字列ベースの型比較を排除する。

use std::fmt;

use crate::ast::BinOp;
use crate::intern::InternedStr;

// ============================================================================
// TypeRepr: トップレベル型表現
// ============================================================================

/// 型表現（出所情報を含む）
#[derive(Debug, Clone)]
pub enum TypeRepr {
    /// C 言語の型（CHeader, Apidoc, InlineFn 共通）
    CType {
        /// 型指定子（int, char, struct X, など）
        specs: CTypeSpecs,
        /// 派生型（ポインタ、配列など）
        derived: Vec<CDerivedType>,
        /// 出所（デバッグ用）
        source: CTypeSource,
    },

    /// Rust バインディングからの型（syn::Type 由来）
    RustType {
        /// 型表現
        repr: RustTypeRepr,
        /// 出所（関数名など）
        source: RustTypeSource,
    },

    /// 推論で導出
    Inferred(InferredType),
}

// ============================================================================
// C 型の出所
// ============================================================================

/// C 型の出所
#[derive(Debug, Clone)]
pub enum CTypeSource {
    /// C ヘッダーのパース結果
    Header,
    /// apidoc（embed.fnc 等）- 元の文字列を保持
    Apidoc { raw: String },
    /// inline 関数の AST
    InlineFn { func_name: InternedStr },
    /// parser.rs の parse_type_from_string を使用して解析
    Parser,
    /// フィールドアクセスからの逆推論
    FieldInference { field_name: InternedStr },
    /// キャスト式の型名（AST から直接変換）
    Cast,
    /// SV ファミリーキャストからの型推論
    SvFamilyCast,
    /// 共通フィールドマクロ宣言フィールドへのアクセス経路から逆推論された
    /// SV ファミリー型（例: `xcv_gv_u` (in `_XPVCV_COMMON`) アクセス →
    /// 引数 `cv` は `*mut CV`）。総称的な `SvFamilyCast` 由来の `*mut SV`
    /// より優先するため、`confidence_tier` で 3 を返す。
    CommonMacroFieldInference,
}

// ============================================================================
// Rust 型の出所
// ============================================================================

/// Rust 型の出所
#[derive(Debug, Clone)]
pub enum RustTypeSource {
    /// bindings.rs の関数引数
    FnParam { func_name: String, param_index: usize },
    /// bindings.rs の関数戻り値
    FnReturn { func_name: String },
    /// bindings.rs の定数
    Const { const_name: String },
    /// 文字列からパースされた型（具体的な出所は不明）
    Parsed { raw: String },
}

// ============================================================================
// C 型の構造化表現
// ============================================================================

/// C 型指定子（DeclSpecs から抽出）
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum CTypeSpecs {
    /// void
    Void,
    /// char (signed: None = plain char, Some(true) = signed, Some(false) = unsigned)
    Char { signed: Option<bool> },
    /// 整数型
    Int { signed: bool, size: IntSize },
    /// float
    Float,
    /// double (is_long: long double かどうか)
    Double { is_long: bool },
    /// _Bool
    Bool,
    /// 構造体/共用体
    Struct { name: Option<InternedStr>, is_union: bool },
    /// enum
    Enum { name: Option<InternedStr> },
    /// typedef 名
    TypedefName(InternedStr),
    /// 未解決の typedef 名（interner に登録されていない場合）
    UnknownTypedef(String),
}

/// 整数サイズ
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum IntSize {
    /// short
    Short,
    /// int (default)
    Int,
    /// long
    Long,
    /// long long
    LongLong,
    /// __int128
    Int128,
}

/// C 派生型
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum CDerivedType {
    /// ポインタ
    Pointer {
        is_const: bool,
        is_volatile: bool,
        is_restrict: bool,
    },
    /// 配列
    Array { size: Option<usize> },
    /// 関数
    Function {
        params: Vec<CTypeSpecs>,
        variadic: bool,
    },
}

// ============================================================================
// Rust 型の構造化表現
// ============================================================================

/// Rust 型表現（syn::Type から変換）
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum RustTypeRepr {
    /// C互換基本型 (c_int, c_char, etc.)
    CPrimitive(CPrimitiveKind),
    /// Rust基本型 (i32, u64, bool, etc.)
    RustPrimitive(RustPrimitiveKind),
    /// ポインタ (*mut T, *const T)
    Pointer {
        inner: Box<RustTypeRepr>,
        is_const: bool,
    },
    /// 参照 (&T, &mut T)
    Reference {
        inner: Box<RustTypeRepr>,
        is_mut: bool,
    },
    /// 名前付き型 (SV, AV, PerlInterpreter, etc.)
    Named(String),
    /// Option<T>
    Option(Box<RustTypeRepr>),
    /// 関数ポインタ
    FnPointer {
        params: Vec<RustTypeRepr>,
        ret: Option<Box<RustTypeRepr>>,
    },
    /// ユニット ()
    Unit,
    /// パース不能だった型（文字列で保持）
    Unknown(String),
}

/// C互換基本型
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum CPrimitiveKind {
    CChar,
    CSchar,
    CUchar,
    CShort,
    CUshort,
    CInt,
    CUint,
    CLong,
    CUlong,
    CLongLong,
    CUlongLong,
    CFloat,
    CDouble,
}

/// Rust基本型
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum RustPrimitiveKind {
    I8,
    I16,
    I32,
    I64,
    I128,
    Isize,
    U8,
    U16,
    U32,
    U64,
    U128,
    Usize,
    F32,
    F64,
    Bool,
}

// ============================================================================
// 推論の根拠 (InferredType)
// ============================================================================

/// 推論で導出された型
#[derive(Debug, Clone)]
pub enum InferredType {
    // ==================== リテラル ====================
    /// 整数リテラル (42, 0x1F, etc.)
    IntLiteral,
    /// 符号なし整数リテラル (42u, etc.)
    UIntLiteral,
    /// 浮動小数点リテラル (3.14, etc.)
    FloatLiteral,
    /// 文字リテラル ('a')
    CharLiteral,
    /// 文字列リテラル ("hello")
    StringLiteral,

    // ==================== 識別子参照 ====================
    /// シンボルテーブルからの参照
    SymbolLookup {
        name: InternedStr,
        /// 解決された型
        resolved_type: Box<TypeRepr>,
    },
    /// THX (my_perl) のデフォルト型
    ThxDefault,

    // ==================== 演算子 ====================
    /// 二項演算の結果
    BinaryOp {
        op: BinOp,
        /// 左右オペランドの型から計算された結果型
        result_type: Box<TypeRepr>,
    },
    /// 単項演算 (+, -, ~)
    UnaryArithmetic {
        /// 内部式の型をそのまま継承
        inner_type: Box<TypeRepr>,
    },
    /// 論理否定 (!) - 常に int
    LogicalNot,
    /// アドレス取得 (&x)
    AddressOf { inner_type: Box<TypeRepr> },
    /// 間接参照 (*p)
    Dereference { pointer_type: Box<TypeRepr> },
    /// インクリメント/デクリメント (++, --)
    IncDec { inner_type: Box<TypeRepr> },

    // ==================== メンバーアクセス ====================
    /// 直接メンバーアクセス (expr.member)
    MemberAccess {
        base_type: String,
        member: InternedStr,
        /// 解決されたフィールド型
        field_type: Option<Box<TypeRepr>>,
    },
    /// ポインタメンバーアクセス (expr->member)
    PtrMemberAccess {
        base_type: String,
        member: InternedStr,
        /// 解決されたフィールド型
        field_type: Option<Box<TypeRepr>>,
        /// 一致型を使用した場合（ベース型が不明時）
        used_consistent_type: bool,
    },

    // ==================== 配列/添字 ====================
    /// 配列添字 (arr[i])
    ArraySubscript {
        base_type: Box<TypeRepr>,
        /// 要素型
        element_type: Box<TypeRepr>,
    },

    // ==================== 条件・制御 ====================
    /// 条件演算子 (cond ? then : else)
    Conditional {
        then_type: Box<TypeRepr>,
        else_type: Box<TypeRepr>,
        /// 計算された共通型
        result_type: Box<TypeRepr>,
    },
    /// コンマ式 (a, b)
    Comma {
        /// 右辺の型
        rhs_type: Box<TypeRepr>,
    },
    /// 代入式 (a = b)
    Assignment {
        /// 左辺の型
        lhs_type: Box<TypeRepr>,
    },

    // ==================== 型操作 ====================
    /// キャスト式 ((type)expr)
    Cast { target_type: Box<TypeRepr> },
    /// sizeof 式/型 - 常に unsigned long
    Sizeof,
    /// alignof - 常に unsigned long
    Alignof,
    /// 複合リテラル ((type){...})
    CompoundLiteral { type_name: Box<TypeRepr> },

    // ==================== その他 ====================
    /// 文式 ({ ... })
    StmtExpr {
        /// 最後の式の型
        last_expr_type: Option<Box<TypeRepr>>,
    },
    /// アサーション - 常に void
    Assert,
    /// 関数呼び出しの戻り値（RustBindings/Apidoc から取得できなかった場合）
    FunctionReturn { func_name: InternedStr },
}

// ============================================================================
// 変換関数
// ============================================================================

impl CTypeSpecs {
    /// DeclSpecs から CTypeSpecs を抽出
    pub fn from_decl_specs(specs: &crate::ast::DeclSpecs, _interner: &crate::intern::StringInterner) -> Self {
        use crate::ast::TypeSpec;

        let mut has_signed = false;
        let mut has_unsigned = false;
        let mut has_short = false;
        let mut has_long: u8 = 0;
        let mut base_type: Option<CTypeSpecs> = None;

        for type_spec in &specs.type_specs {
            match type_spec {
                TypeSpec::Void => base_type = Some(CTypeSpecs::Void),
                TypeSpec::Char => {
                    // char の signed/unsigned は後で決定
                    if base_type.is_none() {
                        base_type = Some(CTypeSpecs::Char { signed: None });
                    }
                }
                TypeSpec::Short => has_short = true,
                TypeSpec::Int => {
                    if base_type.is_none() {
                        base_type = Some(CTypeSpecs::Int {
                            signed: true,
                            size: IntSize::Int,
                        });
                    }
                }
                TypeSpec::Long => has_long += 1,
                TypeSpec::Float => base_type = Some(CTypeSpecs::Float),
                TypeSpec::Double => base_type = Some(CTypeSpecs::Double { is_long: false }),
                TypeSpec::Signed => has_signed = true,
                TypeSpec::Unsigned => has_unsigned = true,
                TypeSpec::Bool => base_type = Some(CTypeSpecs::Bool),
                TypeSpec::Int128 => {
                    base_type = Some(CTypeSpecs::Int {
                        signed: !has_unsigned,
                        size: IntSize::Int128,
                    });
                }
                TypeSpec::Struct(s) => {
                    base_type = Some(CTypeSpecs::Struct {
                        name: s.name,
                        is_union: false,
                    });
                }
                TypeSpec::Union(s) => {
                    base_type = Some(CTypeSpecs::Struct {
                        name: s.name,
                        is_union: true,
                    });
                }
                TypeSpec::Enum(e) => {
                    base_type = Some(CTypeSpecs::Enum { name: e.name });
                }
                TypeSpec::TypedefName(name) => {
                    base_type = Some(CTypeSpecs::TypedefName(*name));
                }
                _ => {}
            }
        }

        // signed/unsigned と short/long の組み合わせを処理
        if has_short {
            return CTypeSpecs::Int {
                signed: !has_unsigned,
                size: IntSize::Short,
            };
        }

        if has_long >= 2 {
            return CTypeSpecs::Int {
                signed: !has_unsigned,
                size: IntSize::LongLong,
            };
        }

        if has_long == 1 {
            if let Some(CTypeSpecs::Double { .. }) = base_type {
                return CTypeSpecs::Double { is_long: true };
            }
            return CTypeSpecs::Int {
                signed: !has_unsigned,
                size: IntSize::Long,
            };
        }

        // char の signed/unsigned を確定
        if let Some(CTypeSpecs::Char { .. }) = base_type {
            if has_signed {
                return CTypeSpecs::Char { signed: Some(true) };
            } else if has_unsigned {
                return CTypeSpecs::Char { signed: Some(false) };
            }
            return CTypeSpecs::Char { signed: None };
        }

        // 単独の signed/unsigned
        if has_unsigned && base_type.is_none() {
            return CTypeSpecs::Int {
                signed: false,
                size: IntSize::Int,
            };
        }
        if has_signed && base_type.is_none() {
            return CTypeSpecs::Int {
                signed: true,
                size: IntSize::Int,
            };
        }

        // int の unsigned
        if has_unsigned {
            if let Some(CTypeSpecs::Int { size, .. }) = base_type {
                return CTypeSpecs::Int {
                    signed: false,
                    size,
                };
            }
        }

        base_type.unwrap_or(CTypeSpecs::Int {
            signed: true,
            size: IntSize::Int,
        })
    }
}

impl CDerivedType {
    /// DerivedDecl のリストから CDerivedType のリストを作成
    pub fn from_derived_decls(derived: &[crate::ast::DerivedDecl]) -> Vec<Self> {
        use crate::ast::ExprKind;

        derived
            .iter()
            .map(|d| match d {
                crate::ast::DerivedDecl::Pointer(quals) => CDerivedType::Pointer {
                    is_const: quals.is_const,
                    is_volatile: quals.is_volatile,
                    is_restrict: quals.is_restrict,
                },
                crate::ast::DerivedDecl::Array(array_decl) => {
                    // 配列サイズが定数リテラルの場合のみ抽出
                    let size = array_decl.size.as_ref().and_then(|expr| {
                        match &expr.kind {
                            ExprKind::IntLit(n) => Some(*n as usize),
                            ExprKind::UIntLit(n) => Some(*n as usize),
                            _ => None,
                        }
                    });
                    CDerivedType::Array { size }
                }
                crate::ast::DerivedDecl::Function(_params) => {
                    // 関数パラメータの詳細は簡略化
                    CDerivedType::Function {
                        params: vec![],
                        variadic: false,
                    }
                }
            })
            .collect()
    }
}

impl RustTypeRepr {
    /// 型文字列から RustTypeRepr をパース
    pub fn from_type_string(s: &str) -> Self {
        let s = s.trim();

        // ユニット型
        if s == "()" {
            return RustTypeRepr::Unit;
        }

        // ポインタ型
        if let Some(rest) = s.strip_prefix("*mut ") {
            return RustTypeRepr::Pointer {
                inner: Box::new(Self::from_type_string(rest)),
                is_const: false,
            };
        }
        if let Some(rest) = s.strip_prefix("* mut ") {
            return RustTypeRepr::Pointer {
                inner: Box::new(Self::from_type_string(rest)),
                is_const: false,
            };
        }
        if let Some(rest) = s.strip_prefix("*const ") {
            return RustTypeRepr::Pointer {
                inner: Box::new(Self::from_type_string(rest)),
                is_const: true,
            };
        }
        if let Some(rest) = s.strip_prefix("* const ") {
            return RustTypeRepr::Pointer {
                inner: Box::new(Self::from_type_string(rest)),
                is_const: true,
            };
        }

        // 参照型
        if let Some(rest) = s.strip_prefix("&mut ") {
            return RustTypeRepr::Reference {
                inner: Box::new(Self::from_type_string(rest)),
                is_mut: true,
            };
        }
        if let Some(rest) = s.strip_prefix("& mut ") {
            return RustTypeRepr::Reference {
                inner: Box::new(Self::from_type_string(rest)),
                is_mut: true,
            };
        }
        if let Some(rest) = s.strip_prefix('&') {
            return RustTypeRepr::Reference {
                inner: Box::new(Self::from_type_string(rest.trim())),
                is_mut: false,
            };
        }

        // C 互換基本型
        if let Some(kind) = Self::parse_c_primitive(s) {
            return RustTypeRepr::CPrimitive(kind);
        }

        // Rust 基本型
        if let Some(kind) = Self::parse_rust_primitive(s) {
            return RustTypeRepr::RustPrimitive(kind);
        }

        // Option<T>
        if s.starts_with("Option<") || s.starts_with(":: std :: option :: Option<") {
            if let Some(inner) = Self::extract_generic_param(s, "Option") {
                return RustTypeRepr::Option(Box::new(Self::from_type_string(&inner)));
            }
        }

        // 名前付き型（識別子）
        if s.chars().next().map(|c| c.is_alphabetic() || c == '_').unwrap_or(false) {
            // パスセパレータを含む場合は最後の部分を使用
            let name = s.split("::").last().unwrap_or(s).trim();
            return RustTypeRepr::Named(name.to_string());
        }

        // パース不能
        RustTypeRepr::Unknown(s.to_string())
    }

    /// C 互換基本型をパース
    fn parse_c_primitive(s: &str) -> Option<CPrimitiveKind> {
        // :: std :: os :: raw :: c_* 形式にも対応
        let s = s.trim();
        let name = if s.contains("::") {
            s.split("::").last()?.trim()
        } else {
            s
        };

        match name {
            "c_char" => Some(CPrimitiveKind::CChar),
            "c_schar" => Some(CPrimitiveKind::CSchar),
            "c_uchar" => Some(CPrimitiveKind::CUchar),
            "c_short" => Some(CPrimitiveKind::CShort),
            "c_ushort" => Some(CPrimitiveKind::CUshort),
            "c_int" => Some(CPrimitiveKind::CInt),
            "c_uint" => Some(CPrimitiveKind::CUint),
            "c_long" => Some(CPrimitiveKind::CLong),
            "c_ulong" => Some(CPrimitiveKind::CUlong),
            "c_longlong" => Some(CPrimitiveKind::CLongLong),
            "c_ulonglong" => Some(CPrimitiveKind::CUlongLong),
            "c_float" => Some(CPrimitiveKind::CFloat),
            "c_double" => Some(CPrimitiveKind::CDouble),
            _ => None,
        }
    }

    /// Rust 基本型をパース
    fn parse_rust_primitive(s: &str) -> Option<RustPrimitiveKind> {
        match s.trim() {
            "i8" => Some(RustPrimitiveKind::I8),
            "i16" => Some(RustPrimitiveKind::I16),
            "i32" => Some(RustPrimitiveKind::I32),
            "i64" => Some(RustPrimitiveKind::I64),
            "i128" => Some(RustPrimitiveKind::I128),
            "isize" => Some(RustPrimitiveKind::Isize),
            "u8" => Some(RustPrimitiveKind::U8),
            "u16" => Some(RustPrimitiveKind::U16),
            "u32" => Some(RustPrimitiveKind::U32),
            "u64" => Some(RustPrimitiveKind::U64),
            "u128" => Some(RustPrimitiveKind::U128),
            "usize" => Some(RustPrimitiveKind::Usize),
            "f32" => Some(RustPrimitiveKind::F32),
            "f64" => Some(RustPrimitiveKind::F64),
            "bool" => Some(RustPrimitiveKind::Bool),
            _ => None,
        }
    }

    /// ジェネリック型のパラメータを抽出
    fn extract_generic_param(s: &str, type_name: &str) -> Option<String> {
        // "Option<T>" または ":: std :: option :: Option<T>" から T を抽出
        let start = s.find(&format!("{}<", type_name))?;
        let after_open = start + type_name.len() + 1;
        let content = &s[after_open..];

        // 対応する > を探す（ネストを考慮）
        let mut depth = 1;
        let mut end = 0;
        for (i, c) in content.char_indices() {
            match c {
                '<' => depth += 1,
                '>' => {
                    depth -= 1;
                    if depth == 0 {
                        end = i;
                        break;
                    }
                }
                _ => {}
            }
        }

        if end > 0 {
            Some(content[..end].trim().to_string())
        } else {
            None
        }
    }
}

impl TypeRepr {
    /// 出所の表示用文字列を取得
    pub fn source_display(&self) -> &'static str {
        match self {
            TypeRepr::CType { source, .. } => match source {
                CTypeSource::Header => "c-header",
                CTypeSource::Apidoc { .. } => "apidoc",
                CTypeSource::InlineFn { .. } => "inline-fn",
                CTypeSource::Parser => "parser",
                CTypeSource::FieldInference { .. } => "field-inference",
                CTypeSource::Cast => "cast",
                CTypeSource::SvFamilyCast => "sv-family-cast",
                CTypeSource::CommonMacroFieldInference => "common-macro-field-inference",
            },
            TypeRepr::RustType { .. } => "rust-bindings",
            TypeRepr::Inferred(_) => "inferred",
        }
    }

    /// void 型かどうかを判定
    ///
    /// ポインタを含まない void 型の場合に true を返す。
    /// `void *` は false を返す（有効なポインタ型のため）。
    /// bindings.rs の FnParam ソースかどうか
    pub fn is_fn_param_source(&self) -> bool {
        matches!(self, TypeRepr::RustType { source: RustTypeSource::FnParam { .. }, .. })
    }

    /// 型情報の確度 Tier を返す
    ///
    /// - Tier 1: bindings.rs (bindgen生成、変更不可)
    /// - Tier 2: C ヘッダー宣言 / inline 関数パラメータ (変更不可)
    /// - Tier 3: apidoc (embed.fnc 等、参考情報)
    /// - Tier 4: 推論結果 (変更可能)
    pub fn confidence_tier(&self) -> u8 {
        match self {
            TypeRepr::RustType { source, .. } => match source {
                RustTypeSource::FnParam { .. }
                | RustTypeSource::FnReturn { .. }
                | RustTypeSource::Const { .. } => 1,
                RustTypeSource::Parsed { .. } => 3,
            },
            TypeRepr::CType { source, .. } => match source {
                CTypeSource::InlineFn { .. } | CTypeSource::Header => 2,
                CTypeSource::Apidoc { .. }
                | CTypeSource::CommonMacroFieldInference => 3,
                CTypeSource::Cast
                | CTypeSource::SvFamilyCast
                | CTypeSource::FieldInference { .. }
                | CTypeSource::Parser => 4,
            },
            TypeRepr::Inferred(_) => 4,
        }
    }

    pub fn is_void(&self) -> bool {
        match self {
            TypeRepr::CType { specs, derived, .. } => {
                // ポインタや配列がない純粋な void のみ true
                derived.is_empty() && matches!(specs, CTypeSpecs::Void)
            }
            TypeRepr::RustType { repr, .. } => {
                matches!(repr, RustTypeRepr::Unit)
            }
            TypeRepr::Inferred(inferred) => {
                match inferred {
                    InferredType::SymbolLookup { resolved_type, .. } => {
                        resolved_type.is_void()
                    }
                    _ => false,
                }
            }
        }
    }

    /// 最外ポインタの is_const を true に変更する
    /// 最外ポインタの is_const を false に変更する（must-mut 用）
    pub fn make_outer_pointer_mut(&mut self) {
        match self {
            TypeRepr::CType { derived, .. } => {
                for d in derived.iter_mut().rev() {
                    if let CDerivedType::Pointer { is_const, .. } = d {
                        *is_const = false;
                        return;
                    }
                }
            }
            TypeRepr::RustType { repr, .. } => {
                if let RustTypeRepr::Pointer { is_const, .. } = repr {
                    *is_const = false;
                }
            }
            _ => {}
        }
    }

    pub fn make_outer_pointer_const(&mut self) {
        match self {
            TypeRepr::CType { derived, .. } => {
                // derived の最後（最外側）のポインタを const に
                for d in derived.iter_mut().rev() {
                    if let CDerivedType::Pointer { is_const, .. } = d {
                        *is_const = true;
                        return;
                    }
                }
            }
            TypeRepr::RustType { repr, .. } => {
                repr.make_outer_pointer_const();
            }
            TypeRepr::Inferred(inferred) => {
                match inferred {
                    InferredType::SymbolLookup { resolved_type, .. } => {
                        resolved_type.make_outer_pointer_const();
                    }
                    InferredType::Cast { target_type } => {
                        target_type.make_outer_pointer_const();
                    }
                    _ => {}
                }
            }
        }
    }

    /// ポインタ型かどうか (`has_outer_pointer` のエイリアス)。
    ///
    /// `Inferred` ラッパは `resolved_type()` を経由して中身を再帰参照する点で
    /// `has_outer_pointer` と挙動が異なる (本メソッドは構造的「実体型」判定に
    /// 使う)。`has_outer_pointer` 自体は既存の使用箇所が `Inferred` を別扱い
    /// しているため挙動を変えない。
    pub fn is_pointer_type(&self) -> bool {
        match self {
            TypeRepr::CType { derived, .. } => {
                derived.iter().any(|d| matches!(d, CDerivedType::Pointer { .. }))
            }
            TypeRepr::RustType { repr, .. } => repr.has_outer_pointer(),
            TypeRepr::Inferred(inferred) => inferred
                .resolved_type()
                .is_some_and(|t| t.is_pointer_type()),
        }
    }

    /// `void *` / `*mut c_void` / `*const c_void` かどうかを **構造的に** 判定する。
    ///
    /// 文字列 `contains("void")` ではなく specs/derived の構造で判定するので、
    /// `*mut struct void_table` のような偽陽性に引っかからない。
    /// `Inferred` ラッパは `resolved_type()` 経由で中身を再帰参照する。
    pub fn is_void_pointer(&self) -> bool {
        match self {
            TypeRepr::CType { specs, derived, .. } => {
                derived.iter().any(|d| matches!(d, CDerivedType::Pointer { .. }))
                    && matches!(specs, CTypeSpecs::Void)
            }
            TypeRepr::RustType { repr, .. } => match repr {
                RustTypeRepr::Pointer { inner, .. } => {
                    matches!(inner.as_ref(), RustTypeRepr::Unit)
                        || matches!(inner.as_ref(), RustTypeRepr::Named(n) if n == "c_void")
                }
                _ => false,
            },
            TypeRepr::Inferred(inferred) => inferred
                .resolved_type()
                .is_some_and(|t| t.is_void_pointer()),
        }
    }

    /// 具体的なポインタ (`void *` ではないポインタ型) かどうか
    pub fn is_concrete_pointer(&self) -> bool {
        self.is_pointer_type() && !self.is_void_pointer()
    }

    /// 最外ポインタを持つかどうか
    ///
    /// 既存呼出側の挙動を変えないため `Inferred` は false を返す
    /// (再帰判定が必要な場合は `is_pointer_type` を使うこと)。
    pub fn has_outer_pointer(&self) -> bool {
        match self {
            TypeRepr::CType { derived, .. } => {
                derived.iter().any(|d| matches!(d, CDerivedType::Pointer { .. }))
            }
            TypeRepr::RustType { repr, .. } => repr.has_outer_pointer(),
            _ => false,
        }
    }

    /// Apidoc の型文字列から TypeRepr を作成
    pub fn from_apidoc_string(s: &str, interner: &crate::intern::StringInterner) -> Self {
        // C 型文字列をパース
        let (specs, derived) = Self::parse_c_type_string(s, interner);
        TypeRepr::CType {
            specs,
            derived,
            source: CTypeSource::Apidoc { raw: s.to_string() },
        }
    }

    /// Rust 形式の型文字列から TypeRepr を作成
    ///
    /// `*mut T`, `*const T`, `c_int` などの Rust 形式の型文字列をパースする。
    /// rust_decl.rs からの型情報の読み込みに使用する。
    pub fn from_rust_string(s: &str) -> Self {
        let repr = RustTypeRepr::from_type_string(s);
        TypeRepr::RustType {
            repr,
            source: RustTypeSource::Parsed {
                raw: s.to_string(),
            },
        }
    }

    /// **構造ベース**: `UnifiedType` から `TypeRepr` を直接構築する。
    ///
    /// bindings.rs (`syn::File`) → `RustField.uty` (`UnifiedType`) で得た
    /// 構造化情報を、文字列を経由せず TypeRepr に変換する。
    /// Pointer / Array / Named / 基本型は `CType` として表現し、
    /// FnPtr / Verbatim / Unknown は表現できないので `RustType` の
    /// `Unknown(canonical_string)` にフォールバックする。
    ///
    /// Source は `CTypeSource::Apidoc { raw }` で記録する (tier 3 相当)。
    /// bindings は本来 tier 1 だが、本メソッドの呼出元 (anonymous union
    /// メンバ解決) は元の C-side フィールド型を補完する用途なので、tier 3
    /// で十分。tier 1 が必要な経路ができたら別 source variant を追加する。
    pub fn from_unified_type(
        ut: &crate::unified_type::UnifiedType,
        interner: &crate::intern::StringInterner,
    ) -> Self {
        let raw = ut.to_rust_string();
        if let Some((specs, derived)) = unified_to_c(ut, interner) {
            return TypeRepr::CType {
                specs,
                derived,
                source: CTypeSource::Apidoc { raw },
            };
        }
        TypeRepr::RustType {
            repr: RustTypeRepr::Unknown(raw.clone()),
            source: RustTypeSource::Parsed { raw },
        }
    }

    /// DeclSpecs と Declarator から TypeRepr を作成
    ///
    /// C ヘッダーのパース結果から直接 TypeRepr を生成する。
    /// fields_dict.rs でのフィールド型収集に使用する。
    pub fn from_decl(
        specs: &crate::ast::DeclSpecs,
        declarator: &crate::ast::Declarator,
        _interner: &crate::intern::StringInterner,
    ) -> Self {
        let c_specs = CTypeSpecs::from_decl_specs(specs, _interner);
        let derived = CDerivedType::from_derived_decls(&declarator.derived);
        TypeRepr::CType {
            specs: c_specs,
            derived,
            source: CTypeSource::Header,
        }
    }

    /// TypeName (パーサー出力) から TypeRepr を作成
    ///
    /// `parser::parse_type_from_string` の結果から TypeRepr を生成する。
    /// `from_apidoc_string` の代替として使用し、完全な C パーサーを活用する。
    pub fn from_type_name(
        type_name: &crate::ast::TypeName,
        interner: &crate::intern::StringInterner,
    ) -> Self {
        let c_specs = CTypeSpecs::from_decl_specs(&type_name.specs, interner);
        let derived = type_name.declarator
            .as_ref()
            .map(|d| CDerivedType::from_derived_decls(&d.derived))
            .unwrap_or_default();
        TypeRepr::CType {
            specs: c_specs,
            derived,
            source: CTypeSource::Parser,
        }
    }

    /// C 型文字列から TypeRepr を作成（パーサー版）
    ///
    /// `parser.rs` の `parse_type_from_string` を使用して完全な C パーサーで解析する。
    /// `files` と `typedefs` が必要なため、`SemanticAnalyzer` など型情報が揃っている
    /// コンテキストでの使用を推奨。
    ///
    /// パースに失敗した場合は `from_apidoc_string` と同じ簡易パーサーにフォールバックする。
    pub fn from_c_type_string(
        s: &str,
        interner: &crate::intern::StringInterner,
        files: &crate::source::FileRegistry,
        typedefs: &std::collections::HashSet<crate::intern::InternedStr>,
    ) -> Self {
        use crate::parser::parse_type_from_string;

        match parse_type_from_string(s, interner, files, typedefs) {
            Ok(type_name) => Self::from_type_name(&type_name, interner),
            Err(_) => {
                // フォールバック: 既存の簡易パーサーを使用
                let (specs, derived) = Self::parse_c_type_string(s, interner);
                TypeRepr::CType {
                    specs,
                    derived,
                    source: CTypeSource::Apidoc { raw: s.to_string() },
                }
            }
        }
    }

    /// C 型文字列をパース（簡易版）
    fn parse_c_type_string(s: &str, interner: &crate::intern::StringInterner) -> (CTypeSpecs, Vec<CDerivedType>) {
        let s = s.trim();

        // Rust 形式 (`*mut T` / `*const T`) は先頭から prefix で剥がす。
        // bindings.rs (`RustField.ty`) 由来の文字列が経由する経路で必要。
        // 通常の C 形式 (`T *`) と混在しないよう、先頭プレフィクスがある間
        // 繰り返し処理する。
        let mut prefix_pointers: Vec<bool> = Vec::new(); // is_const
        let mut current = s;
        loop {
            if let Some(rest) = current.strip_prefix("*mut ") {
                prefix_pointers.push(false);
                current = rest.trim();
            } else if let Some(rest) = current.strip_prefix("*const ") {
                prefix_pointers.push(true);
                current = rest.trim();
            } else {
                break;
            }
        }

        // ポインタ数をカウント
        let mut ptr_count = 0;
        let mut is_const = false;
        let mut base = current;

        // 末尾の * をカウント
        while base.ends_with('*') {
            ptr_count += 1;
            base = base[..base.len() - 1].trim();
        }

        // "const" をチェック
        if base.starts_with("const ") {
            is_const = true;
            base = base[6..].trim();
        }
        if base.ends_with(" const") {
            is_const = true;
            base = base[..base.len() - 6].trim();
        }

        // 基本型をパース
        let specs = Self::parse_c_base_type(base, interner);

        // 派生型を構築
        // 内側の Rust prefix ポインタを最初に積み、続いて C 形式 trailing
        // ポインタを積む。`*mut HV` (Rust) は `HV *` (C) と等価なので
        // 出力 derived は同じ並びになる。
        let mut derived: Vec<CDerivedType> = Vec::with_capacity(prefix_pointers.len() + ptr_count);
        for is_const_p in prefix_pointers.iter().rev() {
            derived.push(CDerivedType::Pointer {
                is_const: *is_const_p,
                is_volatile: false,
                is_restrict: false,
            });
        }
        for i in 0..ptr_count {
            derived.push(CDerivedType::Pointer {
                is_const: i == 0 && is_const,
                is_volatile: false,
                is_restrict: false,
            });
        }

        (specs, derived)
    }

    /// C 基本型文字列をパース
    fn parse_c_base_type(s: &str, interner: &crate::intern::StringInterner) -> CTypeSpecs {
        match s {
            "void" => CTypeSpecs::Void,
            "char" => CTypeSpecs::Char { signed: None },
            "signed char" => CTypeSpecs::Char { signed: Some(true) },
            "unsigned char" => CTypeSpecs::Char { signed: Some(false) },
            "short" | "short int" | "signed short" | "signed short int" => {
                CTypeSpecs::Int { signed: true, size: IntSize::Short }
            }
            "unsigned short" | "unsigned short int" => {
                CTypeSpecs::Int { signed: false, size: IntSize::Short }
            }
            "int" | "signed" | "signed int" => {
                CTypeSpecs::Int { signed: true, size: IntSize::Int }
            }
            "unsigned" | "unsigned int" => {
                CTypeSpecs::Int { signed: false, size: IntSize::Int }
            }
            "long" | "long int" | "signed long" | "signed long int" => {
                CTypeSpecs::Int { signed: true, size: IntSize::Long }
            }
            "unsigned long" | "unsigned long int" => {
                CTypeSpecs::Int { signed: false, size: IntSize::Long }
            }
            "long long" | "long long int" | "signed long long" | "signed long long int" => {
                CTypeSpecs::Int { signed: true, size: IntSize::LongLong }
            }
            "unsigned long long" | "unsigned long long int" => {
                CTypeSpecs::Int { signed: false, size: IntSize::LongLong }
            }
            "float" => CTypeSpecs::Float,
            "double" => CTypeSpecs::Double { is_long: false },
            "long double" => CTypeSpecs::Double { is_long: true },
            "_Bool" | "bool" => CTypeSpecs::Bool,
            _ => {
                // 構造体/共用体/typedef 名として扱う
                if let Some(rest) = s.strip_prefix("struct ") {
                    if let Some(name) = interner.lookup(rest.trim()) {
                        return CTypeSpecs::Struct { name: Some(name), is_union: false };
                    }
                    return CTypeSpecs::Struct { name: None, is_union: false };
                }
                if let Some(rest) = s.strip_prefix("union ") {
                    if let Some(name) = interner.lookup(rest.trim()) {
                        return CTypeSpecs::Struct { name: Some(name), is_union: true };
                    }
                    return CTypeSpecs::Struct { name: None, is_union: true };
                }
                if let Some(rest) = s.strip_prefix("enum ") {
                    if let Some(name) = interner.lookup(rest.trim()) {
                        return CTypeSpecs::Enum { name: Some(name) };
                    }
                    return CTypeSpecs::Enum { name: None };
                }
                // typedef 名
                if let Some(name) = interner.lookup(s) {
                    CTypeSpecs::TypedefName(name)
                } else {
                    // 未知の型は typedef 名として扱う（文字列で保持できないので）
                    // この場合は interner に登録されていないため、後で解決する必要がある
                    CTypeSpecs::Void // フォールバック
                }
            }
        }
    }

    /// 後方互換: 文字列に変換（デバッグ用）
    pub fn to_display_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            TypeRepr::CType { specs, derived, .. } => {
                let base = specs.to_display_string(interner);
                let mut result = base;
                for d in derived {
                    match d {
                        CDerivedType::Pointer { is_const: true, .. } => result.push_str(" *const"),
                        CDerivedType::Pointer { .. } => result.push_str(" *"),
                        CDerivedType::Array { size: Some(n) } => {
                            result.push_str(&format!("[{}]", n));
                        }
                        CDerivedType::Array { size: None } => result.push_str("[]"),
                        CDerivedType::Function { .. } => result.push_str("()"),
                    }
                }
                result
            }
            TypeRepr::RustType { repr, .. } => repr.to_display_string(),
            TypeRepr::Inferred(inferred) => inferred.to_display_string(interner),
        }
    }

    /// Rust コード生成用の型文字列に変換
    pub fn to_rust_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            TypeRepr::CType { specs, derived, .. } => {
                let base = specs.to_rust_string(interner);
                // ポインタは逆順に適用（Rustの表記に合わせる）
                let mut result = base;
                for d in derived.iter().rev() {
                    // void ポインタの場合は c_void を使用
                    if result == "()" && matches!(d, CDerivedType::Pointer { .. } | CDerivedType::Array { .. }) {
                        result = "c_void".to_string();
                    }
                    result = match d {
                        CDerivedType::Pointer { is_const: true, .. } => format!("*const {}", result),
                        CDerivedType::Pointer { .. } => format!("*mut {}", result),
                        CDerivedType::Array { size: Some(n) } => format!("[{}; {}]", result, n),
                        CDerivedType::Array { size: None } => format!("*mut {}", result),
                        CDerivedType::Function { .. } => format!("/* fn */"),
                    };
                }
                result
            }
            TypeRepr::RustType { repr, .. } => repr.to_display_string(),
            TypeRepr::Inferred(inferred) => inferred.to_rust_string(interner),
        }
    }
}

// ============================================================================
// `UnifiedType` → `(CTypeSpecs, Vec<CDerivedType>)` 構造的変換
// ============================================================================

/// `UnifiedType` を C 型表現 (specs + derived) に分解する。
/// FnPtr / Verbatim / Unknown は C 表現に落とせないので `None` を返す。
fn unified_to_c(
    ut: &crate::unified_type::UnifiedType,
    interner: &crate::intern::StringInterner,
) -> Option<(CTypeSpecs, Vec<CDerivedType>)> {
    use crate::unified_type::{UnifiedType as UT, IntSize as UIS};

    match ut {
        UT::Void => Some((CTypeSpecs::Void, vec![])),
        UT::Bool => Some((CTypeSpecs::Bool, vec![])),
        UT::Char { signed } => Some((CTypeSpecs::Char { signed: *signed }, vec![])),
        UT::Int { signed, size } => {
            // UnifiedType::IntSize::Char は C の signed/unsigned char に倒す
            // (TypeRepr::IntSize には Char バリアントが無い)
            if matches!(size, UIS::Char) {
                return Some((CTypeSpecs::Char { signed: Some(*signed) }, vec![]));
            }
            let target = match size {
                UIS::Char => unreachable!(),
                UIS::Short => IntSize::Short,
                UIS::Int => IntSize::Int,
                UIS::Long => IntSize::Long,
                UIS::LongLong => IntSize::LongLong,
                UIS::Int128 => IntSize::Int128,
            };
            Some((CTypeSpecs::Int { signed: *signed, size: target }, vec![]))
        }
        UT::Float => Some((CTypeSpecs::Float, vec![])),
        UT::Double => Some((CTypeSpecs::Double { is_long: false }, vec![])),
        UT::LongDouble => Some((CTypeSpecs::Double { is_long: true }, vec![])),
        UT::Pointer { inner, is_const } => {
            let (specs, mut derived) = unified_to_c(inner, interner)?;
            // 最も外側の derived として Pointer を追加 (derived 配列は外→内順)
            derived.insert(
                0,
                CDerivedType::Pointer {
                    is_const: *is_const,
                    is_volatile: false,
                    is_restrict: false,
                },
            );
            Some((specs, derived))
        }
        UT::Array { inner, size } => {
            let (specs, mut derived) = unified_to_c(inner, interner)?;
            derived.insert(0, CDerivedType::Array { size: *size });
            Some((specs, derived))
        }
        UT::Named(name) => {
            let specs = match interner.lookup(name) {
                Some(id) => CTypeSpecs::TypedefName(id),
                None => CTypeSpecs::UnknownTypedef(name.clone()),
            };
            Some((specs, vec![]))
        }
        UT::FnPtr { .. } | UT::Verbatim(_) | UT::Unknown => None,
    }
}

// ============================================================================
// 型名抽出メソッド（文字列ラウンドトリップ廃止用）
// ============================================================================

impl TypeRepr {
    /// ポインタ型の参照先の構造体/typedef 名を InternedStr で取得
    ///
    /// PtrMember (->) の base 型から構造体名を抽出するために使用。
    /// 例: `*mut SV` → `Some(SV)`, `XPVHV *` → `Some(XPVHV)`
    pub fn pointee_name(&self) -> Option<InternedStr> {
        match self {
            TypeRepr::CType { specs, derived, .. } => {
                if derived.iter().any(|d| matches!(d, CDerivedType::Pointer { .. })) {
                    specs.type_name()
                } else {
                    None
                }
            }
            TypeRepr::RustType { repr, .. } => repr.pointee_name(),
            TypeRepr::Inferred(inferred) => inferred.resolved_type()?.pointee_name(),
        }
    }

    /// 非ポインタ型の構造体/typedef 名を InternedStr で取得
    ///
    /// Member (.) の base 型から構造体名を抽出するために使用。
    /// 例: `union _xhvnameu` → `Some(_xhvnameu)`, `SV` → `Some(SV)`
    pub fn type_name(&self) -> Option<InternedStr> {
        match self {
            TypeRepr::CType { specs, .. } => specs.type_name(),
            TypeRepr::RustType { repr, .. } => repr.type_name(),
            TypeRepr::Inferred(inferred) => inferred.resolved_type()?.type_name(),
        }
    }
}

impl CTypeSpecs {
    /// 構造体/typedef/enum 名を InternedStr で取得
    pub fn type_name(&self) -> Option<InternedStr> {
        match self {
            CTypeSpecs::Struct { name: Some(n), .. } => Some(*n),
            CTypeSpecs::TypedefName(n) => Some(*n),
            CTypeSpecs::Enum { name: Some(n) } => Some(*n),
            _ => None,
        }
    }
}

impl InferredType {
    /// Inferred ラッパーを解決して内側の TypeRepr を返す
    ///
    /// 各 InferredType バリアントが保持する「結果の型」を取得する。
    /// `pointee_name()` / `type_name()` から再帰的に呼ばれる。
    pub fn resolved_type(&self) -> Option<&TypeRepr> {
        match self {
            InferredType::Cast { target_type } => Some(target_type),
            InferredType::PtrMemberAccess { field_type: Some(ft), .. } => Some(ft),
            InferredType::MemberAccess { field_type: Some(ft), .. } => Some(ft),
            InferredType::ArraySubscript { element_type, .. } => Some(element_type),
            InferredType::AddressOf { inner_type } => Some(inner_type),
            InferredType::Dereference { pointer_type } => Some(pointer_type),
            InferredType::SymbolLookup { resolved_type, .. } => Some(resolved_type),
            InferredType::IncDec { inner_type } => Some(inner_type),
            InferredType::Assignment { lhs_type } => Some(lhs_type),
            InferredType::Comma { rhs_type } => Some(rhs_type),
            InferredType::Conditional { result_type, .. } => Some(result_type),
            InferredType::BinaryOp { result_type, .. } => Some(result_type),
            InferredType::UnaryArithmetic { inner_type } => Some(inner_type),
            InferredType::CompoundLiteral { type_name } => Some(type_name),
            InferredType::StmtExpr { last_expr_type } => last_expr_type.as_deref(),
            _ => None,
        }
    }
}

impl RustTypeRepr {
    /// ポインタ型の参照先の型名を InternedStr で取得
    ///
    /// RustTypeRepr は String ベースで型名を格納しているため、
    /// InternedStr の取得には interner が必要。当面は None を返す。
    fn pointee_name(&self) -> Option<InternedStr> {
        // RustTypeRepr は String ベースのため InternedStr を直接取得できない。
        // 将来的に RustTypeRepr 自体を InternedStr ベースに改修する際に対応する。
        None
    }

    /// 型名を InternedStr で取得
    fn type_name(&self) -> Option<InternedStr> {
        None
    }
}

// ============================================================================
// Display 実装
// ============================================================================

impl CTypeSpecs {
    /// 表示用文字列に変換
    pub fn to_display_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            CTypeSpecs::Void => "void".to_string(),
            CTypeSpecs::Char { signed: None } => "char".to_string(),
            CTypeSpecs::Char { signed: Some(true) } => "signed char".to_string(),
            CTypeSpecs::Char { signed: Some(false) } => "unsigned char".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Short } => "short".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Short } => "unsigned short".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Int } => "int".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Int } => "unsigned int".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Long } => "long".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Long } => "unsigned long".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::LongLong } => "long long".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::LongLong } => "unsigned long long".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Int128 } => "__int128".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Int128 } => "unsigned __int128".to_string(),
            CTypeSpecs::Float => "float".to_string(),
            CTypeSpecs::Double { is_long: false } => "double".to_string(),
            CTypeSpecs::Double { is_long: true } => "long double".to_string(),
            CTypeSpecs::Bool => "_Bool".to_string(),
            CTypeSpecs::Struct { name: Some(n), is_union: false } => {
                format!("struct {}", interner.get(*n))
            }
            CTypeSpecs::Struct { name: None, is_union: false } => "struct".to_string(),
            CTypeSpecs::Struct { name: Some(n), is_union: true } => {
                format!("union {}", interner.get(*n))
            }
            CTypeSpecs::Struct { name: None, is_union: true } => "union".to_string(),
            CTypeSpecs::Enum { name: Some(n) } => format!("enum {}", interner.get(*n)),
            CTypeSpecs::Enum { name: None } => "enum".to_string(),
            CTypeSpecs::TypedefName(n) => interner.get(*n).to_string(),
            CTypeSpecs::UnknownTypedef(s) => s.clone(),
        }
    }

    /// Rust コード生成用の型文字列に変換
    pub fn to_rust_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            CTypeSpecs::Void => "()".to_string(),
            CTypeSpecs::Char { signed: None } => "c_char".to_string(),
            CTypeSpecs::Char { signed: Some(true) } => "c_schar".to_string(),
            CTypeSpecs::Char { signed: Some(false) } => "c_uchar".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Short } => "c_short".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Short } => "c_ushort".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Int } => "c_int".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Int } => "c_uint".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Long } => "c_long".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Long } => "c_ulong".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::LongLong } => "c_longlong".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::LongLong } => "c_ulonglong".to_string(),
            CTypeSpecs::Int { signed: true, size: IntSize::Int128 } => "i128".to_string(),
            CTypeSpecs::Int { signed: false, size: IntSize::Int128 } => "u128".to_string(),
            CTypeSpecs::Float => "c_float".to_string(),
            CTypeSpecs::Double { is_long: false } => "c_double".to_string(),
            CTypeSpecs::Double { is_long: true } => "c_double".to_string(), // long double → c_double
            CTypeSpecs::Bool => "bool".to_string(),
            CTypeSpecs::Struct { name: Some(n), .. } => interner.get(*n).to_string(),
            CTypeSpecs::Struct { name: None, .. } => "/* anonymous struct */".to_string(),
            CTypeSpecs::Enum { name: Some(n) } => interner.get(*n).to_string(),
            CTypeSpecs::Enum { name: None } => "/* anonymous enum */".to_string(),
            CTypeSpecs::TypedefName(n) => interner.get(*n).to_string(),
            CTypeSpecs::UnknownTypedef(s) => s.clone(),
        }
    }
}

impl RustTypeRepr {
    /// 最外ポインタの is_const を true に変更する
    pub fn make_outer_pointer_const(&mut self) {
        if let RustTypeRepr::Pointer { is_const, .. } = self {
            *is_const = true;
        }
    }

    /// 最外ポインタを持つかどうか
    pub fn has_outer_pointer(&self) -> bool {
        matches!(self, RustTypeRepr::Pointer { .. })
    }
}

impl RustTypeRepr {
    /// 表示用文字列に変換
    pub fn to_display_string(&self) -> String {
        match self {
            RustTypeRepr::CPrimitive(kind) => kind.to_string(),
            RustTypeRepr::RustPrimitive(kind) => kind.to_string(),
            RustTypeRepr::Pointer { inner, is_const: true } => {
                format!("*const {}", inner.to_display_string())
            }
            RustTypeRepr::Pointer { inner, is_const: false } => {
                format!("*mut {}", inner.to_display_string())
            }
            RustTypeRepr::Reference { inner, is_mut: true } => {
                format!("&mut {}", inner.to_display_string())
            }
            RustTypeRepr::Reference { inner, is_mut: false } => {
                format!("&{}", inner.to_display_string())
            }
            RustTypeRepr::Named(name) => name.clone(),
            RustTypeRepr::Option(inner) => format!("Option<{}>", inner.to_display_string()),
            RustTypeRepr::FnPointer { params, ret } => {
                let params_str: Vec<_> = params.iter().map(|p| p.to_display_string()).collect();
                let ret_str = ret
                    .as_ref()
                    .map(|r| format!(" -> {}", r.to_display_string()))
                    .unwrap_or_default();
                format!("fn({}){}", params_str.join(", "), ret_str)
            }
            RustTypeRepr::Unit => "()".to_string(),
            RustTypeRepr::Unknown(s) => s.clone(),
        }
    }
}

impl fmt::Display for CPrimitiveKind {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let s = match self {
            CPrimitiveKind::CChar => "c_char",
            CPrimitiveKind::CSchar => "c_schar",
            CPrimitiveKind::CUchar => "c_uchar",
            CPrimitiveKind::CShort => "c_short",
            CPrimitiveKind::CUshort => "c_ushort",
            CPrimitiveKind::CInt => "c_int",
            CPrimitiveKind::CUint => "c_uint",
            CPrimitiveKind::CLong => "c_long",
            CPrimitiveKind::CUlong => "c_ulong",
            CPrimitiveKind::CLongLong => "c_longlong",
            CPrimitiveKind::CUlongLong => "c_ulonglong",
            CPrimitiveKind::CFloat => "c_float",
            CPrimitiveKind::CDouble => "c_double",
        };
        write!(f, "{}", s)
    }
}

impl fmt::Display for RustPrimitiveKind {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let s = match self {
            RustPrimitiveKind::I8 => "i8",
            RustPrimitiveKind::I16 => "i16",
            RustPrimitiveKind::I32 => "i32",
            RustPrimitiveKind::I64 => "i64",
            RustPrimitiveKind::I128 => "i128",
            RustPrimitiveKind::Isize => "isize",
            RustPrimitiveKind::U8 => "u8",
            RustPrimitiveKind::U16 => "u16",
            RustPrimitiveKind::U32 => "u32",
            RustPrimitiveKind::U64 => "u64",
            RustPrimitiveKind::U128 => "u128",
            RustPrimitiveKind::Usize => "usize",
            RustPrimitiveKind::F32 => "f32",
            RustPrimitiveKind::F64 => "f64",
            RustPrimitiveKind::Bool => "bool",
        };
        write!(f, "{}", s)
    }
}

impl InferredType {
    /// 表示用文字列に変換
    pub fn to_display_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            InferredType::IntLiteral => "int".to_string(),
            InferredType::UIntLiteral => "unsigned int".to_string(),
            InferredType::FloatLiteral => "double".to_string(),
            InferredType::CharLiteral => "int".to_string(),
            InferredType::StringLiteral => "char *".to_string(),
            InferredType::SymbolLookup { resolved_type, .. } => {
                resolved_type.to_display_string(interner)
            }
            InferredType::ThxDefault => "*mut PerlInterpreter".to_string(),
            InferredType::BinaryOp { result_type, .. } => result_type.to_display_string(interner),
            InferredType::UnaryArithmetic { inner_type } => inner_type.to_display_string(interner),
            InferredType::LogicalNot => "int".to_string(),
            InferredType::AddressOf { inner_type } => {
                format!("{} *", inner_type.to_display_string(interner))
            }
            InferredType::Dereference { pointer_type } => {
                let s = pointer_type.to_display_string(interner);
                s.trim_end_matches(" *").to_string()
            }
            InferredType::IncDec { inner_type } => inner_type.to_display_string(interner),
            InferredType::MemberAccess { field_type: Some(ft), .. } => {
                ft.to_display_string(interner)
            }
            InferredType::MemberAccess { base_type, member, .. } => {
                format!("{}.{}", base_type, interner.get(*member))
            }
            InferredType::PtrMemberAccess { field_type: Some(ft), .. } => {
                ft.to_display_string(interner)
            }
            InferredType::PtrMemberAccess { base_type, member, .. } => {
                format!("{}->{}", base_type, interner.get(*member))
            }
            InferredType::ArraySubscript { element_type, .. } => {
                element_type.to_display_string(interner)
            }
            InferredType::Conditional { result_type, .. } => {
                result_type.to_display_string(interner)
            }
            InferredType::Comma { rhs_type } => rhs_type.to_display_string(interner),
            InferredType::Assignment { lhs_type } => lhs_type.to_display_string(interner),
            InferredType::Cast { target_type } => target_type.to_display_string(interner),
            InferredType::Sizeof | InferredType::Alignof => "unsigned long".to_string(),
            InferredType::CompoundLiteral { type_name } => type_name.to_display_string(interner),
            InferredType::StmtExpr { last_expr_type: Some(t) } => t.to_display_string(interner),
            InferredType::StmtExpr { last_expr_type: None } => "void".to_string(),
            InferredType::Assert => "void".to_string(),
            InferredType::FunctionReturn { func_name } => {
                format!("{}()", interner.get(*func_name))
            }
        }
    }

    /// Rust コード生成用の型文字列に変換
    pub fn to_rust_string(&self, interner: &crate::intern::StringInterner) -> String {
        match self {
            InferredType::IntLiteral => "c_int".to_string(),
            InferredType::UIntLiteral => "c_uint".to_string(),
            InferredType::FloatLiteral => "c_double".to_string(),
            InferredType::CharLiteral => "c_int".to_string(),
            InferredType::StringLiteral => "*const c_char".to_string(),
            InferredType::SymbolLookup { resolved_type, .. } => {
                resolved_type.to_rust_string(interner)
            }
            InferredType::ThxDefault => "*mut PerlInterpreter".to_string(),
            InferredType::BinaryOp { result_type, .. } => result_type.to_rust_string(interner),
            InferredType::UnaryArithmetic { inner_type } => inner_type.to_rust_string(interner),
            InferredType::LogicalNot => "c_int".to_string(),
            InferredType::AddressOf { inner_type } => {
                format!("*mut {}", inner_type.to_rust_string(interner))
            }
            InferredType::Dereference { pointer_type } => {
                let s = pointer_type.to_rust_string(interner);
                // *mut T → T
                s.strip_prefix("*mut ").or_else(|| s.strip_prefix("*const "))
                    .unwrap_or(&s).to_string()
            }
            InferredType::IncDec { inner_type } => inner_type.to_rust_string(interner),
            InferredType::MemberAccess { field_type: Some(ft), .. } => {
                ft.to_rust_string(interner)
            }
            InferredType::MemberAccess { base_type, member, .. } => {
                format!("/* {}.{} */", base_type, interner.get(*member))
            }
            InferredType::PtrMemberAccess { field_type: Some(ft), .. } => {
                ft.to_rust_string(interner)
            }
            InferredType::PtrMemberAccess { base_type, member, .. } => {
                format!("/* {}->{} */", base_type, interner.get(*member))
            }
            InferredType::ArraySubscript { element_type, .. } => {
                element_type.to_rust_string(interner)
            }
            InferredType::Conditional { result_type, .. } => {
                result_type.to_rust_string(interner)
            }
            InferredType::Comma { rhs_type } => rhs_type.to_rust_string(interner),
            InferredType::Assignment { lhs_type } => lhs_type.to_rust_string(interner),
            InferredType::Cast { target_type } => target_type.to_rust_string(interner),
            InferredType::Sizeof | InferredType::Alignof => "c_ulong".to_string(),
            InferredType::CompoundLiteral { type_name } => type_name.to_rust_string(interner),
            InferredType::StmtExpr { last_expr_type: Some(t) } => t.to_rust_string(interner),
            InferredType::StmtExpr { last_expr_type: None } => "()".to_string(),
            InferredType::Assert => "()".to_string(),
            InferredType::FunctionReturn { func_name } => {
                format!("/* {}() ret */", interner.get(*func_name))
            }
        }
    }
}

// ============================================================================
// テスト
// ============================================================================

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_rust_type_repr_from_string() {
        assert!(matches!(
            RustTypeRepr::from_type_string("c_int"),
            RustTypeRepr::CPrimitive(CPrimitiveKind::CInt)
        ));

        assert!(matches!(
            RustTypeRepr::from_type_string("i32"),
            RustTypeRepr::RustPrimitive(RustPrimitiveKind::I32)
        ));

        assert!(matches!(
            RustTypeRepr::from_type_string("()"),
            RustTypeRepr::Unit
        ));

        if let RustTypeRepr::Pointer { inner, is_const: false } =
            RustTypeRepr::from_type_string("*mut SV")
        {
            assert!(matches!(*inner, RustTypeRepr::Named(ref n) if n == "SV"));
        } else {
            panic!("Expected *mut SV");
        }

        if let RustTypeRepr::Pointer { inner, is_const: true } =
            RustTypeRepr::from_type_string("*const c_char")
        {
            assert!(matches!(*inner, RustTypeRepr::CPrimitive(CPrimitiveKind::CChar)));
        } else {
            panic!("Expected *const c_char");
        }
    }

    #[test]
    fn test_rust_type_repr_from_string_with_spaces() {
        // syn の出力形式（スペースあり）
        if let RustTypeRepr::Pointer { inner, is_const: false } =
            RustTypeRepr::from_type_string("* mut SV")
        {
            assert!(matches!(*inner, RustTypeRepr::Named(ref n) if n == "SV"));
        } else {
            panic!("Expected * mut SV");
        }
    }

    #[test]
    fn test_c_primitive_display() {
        assert_eq!(CPrimitiveKind::CInt.to_string(), "c_int");
        assert_eq!(CPrimitiveKind::CUlong.to_string(), "c_ulong");
    }

    #[test]
    fn test_rust_primitive_display() {
        assert_eq!(RustPrimitiveKind::I32.to_string(), "i32");
        assert_eq!(RustPrimitiveKind::Usize.to_string(), "usize");
    }

    // === Stage 5: 構造的 pointer 判定 (`is_pointer_type` / `is_void_pointer`) ===

    fn make_void_ptr() -> TypeRepr {
        TypeRepr::CType {
            specs: CTypeSpecs::Void,
            derived: vec![CDerivedType::Pointer {
                is_const: false,
                is_volatile: false,
                is_restrict: false,
            }],
            source: CTypeSource::Apidoc { raw: "void *".to_string() },
        }
    }

    fn make_concrete_ptr() -> TypeRepr {
        TypeRepr::CType {
            specs: CTypeSpecs::Char { signed: None },
            derived: vec![CDerivedType::Pointer {
                is_const: false,
                is_volatile: false,
                is_restrict: false,
            }],
            source: CTypeSource::Apidoc { raw: "char *".to_string() },
        }
    }

    #[test]
    fn test_void_pointer_structural() {
        let vp = make_void_ptr();
        assert!(vp.is_pointer_type());
        assert!(vp.is_void_pointer());
        assert!(!vp.is_concrete_pointer());
    }

    #[test]
    fn test_concrete_pointer_structural() {
        let cp = make_concrete_ptr();
        assert!(cp.is_pointer_type());
        assert!(!cp.is_void_pointer());
        assert!(cp.is_concrete_pointer());
    }

    #[test]
    fn test_inferred_member_access_pointer_recursive() {
        // bindings.rs 経由で MemberAccess の field_type が `*mut c_char` のとき、
        // `is_pointer_type` は Inferred を再帰参照して true を返すべき。
        // (Stage 4 までの `has_outer_pointer` は false を返してしまう)
        let inner = make_concrete_ptr();
        let inferred = TypeRepr::Inferred(InferredType::MemberAccess {
            base_type: "xpvcv".to_string(),
            member: crate::intern::StringInterner::new().intern("foo"),
            field_type: Some(Box::new(inner)),
        });
        assert!(inferred.is_pointer_type());
        assert!(!inferred.is_void_pointer());
        assert!(inferred.is_concrete_pointer());
        // 一方、has_outer_pointer は既存挙動 (Inferred → false) を維持
        assert!(!inferred.has_outer_pointer());
    }
}