utoipa_gen/component/

features.rs

use std::{fmt::Display, mem, str::FromStr};

use proc_macro2::{Ident, Span, TokenStream};
use proc_macro_error::abort;
use quote::{quote, ToTokens};
use syn::{parenthesized, parse::ParseStream, LitFloat, LitInt, LitStr, TypePath};

use crate::{
    parse_utils,
    path::parameter::{self, ParameterStyle},
    schema_type::{SchemaFormat, SchemaType},
    AnyValue,
};

use super::{schema, serde::RenameRule, GenericType, TypeTree};

/// Parse `LitInt` from parse stream
fn parse_integer<T: FromStr + Display>(input: ParseStream) -> syn::Result<T>
where
    <T as FromStr>::Err: Display,
{
    parse_utils::parse_next(input, || input.parse::<LitInt>()?.base10_parse())
}

/// Parse any `number`. Tries to parse `LitInt` or `LitFloat` from parse stream.
fn parse_number<T>(input: ParseStream) -> syn::Result<T>
where
    T: FromStr,
    <T as FromStr>::Err: Display,
{
    parse_utils::parse_next(input, || {
        let lookup = input.lookahead1();
        if lookup.peek(LitInt) {
            input.parse::<LitInt>()?.base10_parse()
        } else if lookup.peek(LitFloat) {
            input.parse::<LitFloat>()?.base10_parse()
        } else {
            Err(lookup.error())
        }
    })
}

pub trait Name {
    fn get_name() -> &'static str
    where
        Self: Sized;
}

macro_rules! name {
    ( $ident:ident = $name:literal ) => {
        impl Name for $ident {
            fn get_name() -> &'static str {
                $name
            }
        }

        impl Display for $ident {
            fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
                let name = <Self as Name>::get_name();
                write!(f, "{name}")
            }
        }
    };
}

/// Define whether [`Feature`] variant is validatable or not
pub trait Validatable {
    fn is_validatable(&self) -> bool {
        false
    }
}

pub trait Validate: Validatable {
    /// Perform validation check against schema type.
    fn validate(&self, validator: impl Validator);
}

pub trait Parse {
    fn parse(input: ParseStream, attribute: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized;
}

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub enum Feature {
    Example(Example),
    Default(Default),
    Inline(Inline),
    XmlAttr(XmlAttr),
    Format(Format),
    ValueType(ValueType),
    WriteOnly(WriteOnly),
    ReadOnly(ReadOnly),
    Title(Title),
    Nullable(Nullable),
    Rename(Rename),
    RenameAll(RenameAll),
    Style(Style),
    AllowReserved(AllowReserved),
    Explode(Explode),
    ParameterIn(ParameterIn),
    IntoParamsNames(Names),
    MultipleOf(MultipleOf),
    Maximum(Maximum),
    Minimum(Minimum),
    ExclusiveMaximum(ExclusiveMaximum),
    ExclusiveMinimum(ExclusiveMinimum),
    MaxLength(MaxLength),
    MinLength(MinLength),
    Pattern(Pattern),
    MaxItems(MaxItems),
    MinItems(MinItems),
    MaxProperties(MaxProperties),
    MinProperties(MinProperties),
    SchemaWith(SchemaWith),
    Description(Description),
    Deprecated(Deprecated),
    As(As),
    AdditionalProperties(AdditionalProperties),
    Required(Required),
}

impl Feature {
    pub fn validate(&self, schema_type: &SchemaType, type_tree: &TypeTree) {
        match self {
            Feature::MultipleOf(multiple_of) => multiple_of.validate(
                ValidatorChain::new(&IsNumber(schema_type)).next(&AboveZeroF64(multiple_of.0)),
            ),
            Feature::Maximum(maximum) => maximum.validate(IsNumber(schema_type)),
            Feature::Minimum(minimum) => minimum.validate(IsNumber(schema_type)),
            Feature::ExclusiveMaximum(exclusive_maximum) => {
                exclusive_maximum.validate(IsNumber(schema_type))
            }
            Feature::ExclusiveMinimum(exclusive_minimum) => {
                exclusive_minimum.validate(IsNumber(schema_type))
            }
            Feature::MaxLength(max_length) => max_length.validate(
                ValidatorChain::new(&IsString(schema_type)).next(&AboveZeroUsize(max_length.0)),
            ),
            Feature::MinLength(min_length) => min_length.validate(
                ValidatorChain::new(&IsString(schema_type)).next(&AboveZeroUsize(min_length.0)),
            ),
            Feature::Pattern(pattern) => pattern.validate(IsString(schema_type)),
            Feature::MaxItems(max_items) => max_items.validate(
                ValidatorChain::new(&AboveZeroUsize(max_items.0)).next(&IsVec(type_tree)),
            ),
            Feature::MinItems(min_items) => min_items.validate(
                ValidatorChain::new(&AboveZeroUsize(min_items.0)).next(&IsVec(type_tree)),
            ),
            _unsupported_variant => {
                const SUPPORTED_VARIANTS: [&str; 10] = [
                    "multiple_of",
                    "maximum",
                    "minimum",
                    "exclusive_maximum",
                    "exclusive_minimum",
                    "max_length",
                    "min_length",
                    "pattern",
                    "max_items",
                    "min_items",
                ];
                panic!(
                    "Unsupported variant: `{variant}` for Validate::validate, expected one of: {variants}",
                    variant = _unsupported_variant,
                    variants = SUPPORTED_VARIANTS.join(", ")
                )
            }
        }
    }
}

impl ToTokens for Feature {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        let feature = match &self {
            Feature::Default(default) => quote! { .default(#default) },
            Feature::Example(example) => quote! { .example(Some(#example)) },
            Feature::XmlAttr(xml) => quote! { .xml(Some(#xml)) },
            Feature::Format(format) => quote! { .format(Some(#format)) },
            Feature::WriteOnly(write_only) => quote! { .write_only(Some(#write_only)) },
            Feature::ReadOnly(read_only) => quote! { .read_only(Some(#read_only)) },
            Feature::Title(title) => quote! { .title(Some(#title)) },
            Feature::Nullable(nullable) => quote! { .nullable(#nullable) },
            Feature::Rename(rename) => rename.to_token_stream(),
            Feature::Style(style) => quote! { .style(Some(#style)) },
            Feature::ParameterIn(parameter_in) => quote! { .parameter_in(#parameter_in) },
            Feature::MultipleOf(multiple_of) => quote! { .multiple_of(Some(#multiple_of)) },
            Feature::AllowReserved(allow_reserved) => {
                quote! { .allow_reserved(Some(#allow_reserved)) }
            }
            Feature::Explode(explode) => quote! { .explode(Some(#explode)) },
            Feature::Maximum(maximum) => quote! { .maximum(Some(#maximum)) },
            Feature::Minimum(minimum) => quote! { .minimum(Some(#minimum)) },
            Feature::ExclusiveMaximum(exclusive_maximum) => {
                quote! { .exclusive_maximum(Some(#exclusive_maximum)) }
            }
            Feature::ExclusiveMinimum(exclusive_minimum) => {
                quote! { .exclusive_minimum(Some(#exclusive_minimum)) }
            }
            Feature::MaxLength(max_length) => quote! { .max_length(Some(#max_length)) },
            Feature::MinLength(min_length) => quote! { .min_length(Some(#min_length)) },
            Feature::Pattern(pattern) => quote! { .pattern(Some(#pattern)) },
            Feature::MaxItems(max_items) => quote! { .max_items(Some(#max_items)) },
            Feature::MinItems(min_items) => quote! { .min_items(Some(#min_items)) },
            Feature::MaxProperties(max_properties) => {
                quote! { .max_properties(Some(#max_properties)) }
            }
            Feature::MinProperties(min_properties) => {
                quote! { .max_properties(Some(#min_properties)) }
            }
            Feature::SchemaWith(schema_with) => schema_with.to_token_stream(),
            Feature::Description(description) => quote! { .description(Some(#description)) },
            Feature::Deprecated(deprecated) => quote! { .deprecated(Some(#deprecated)) },
            Feature::AdditionalProperties(additional_properties) => {
                quote! { .additional_properties(Some(#additional_properties)) }
            }
            Feature::RenameAll(_) => {
                abort! {
                    Span::call_site(),
                    "RenameAll feature does not support `ToTokens`"
                }
            }
            Feature::ValueType(_) => {
                abort! {
                    Span::call_site(),
                    "ValueType feature does not support `ToTokens`";
                    help = "ValueType is supposed to be used with `TypeTree` in same manner as a resolved struct/field type.";
                }
            }
            Feature::Inline(_) => {
                // inline feature is ignored by `ToTokens`
                TokenStream::new()
            }
            Feature::IntoParamsNames(_) => {
                abort! {
                    Span::call_site(),
                    "Names feature does not support `ToTokens`";
                    help = "Names is only used with IntoParams to artificially give names for unnamed struct type `IntoParams`."
                }
            }
            Feature::As(_) => {
                abort!(Span::call_site(), "As does not support `ToTokens`")
            }
            Feature::Required(required) => {
                let name = <Required as Name>::get_name();
                quote! { .#name(#required) }
            }
        };

        tokens.extend(feature)
    }
}

impl Display for Feature {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        match self {
            Feature::Default(default) => default.fmt(f),
            Feature::Example(example) => example.fmt(f),
            Feature::XmlAttr(xml) => xml.fmt(f),
            Feature::Format(format) => format.fmt(f),
            Feature::WriteOnly(write_only) => write_only.fmt(f),
            Feature::ReadOnly(read_only) => read_only.fmt(f),
            Feature::Title(title) => title.fmt(f),
            Feature::Nullable(nullable) => nullable.fmt(f),
            Feature::Rename(rename) => rename.fmt(f),
            Feature::Style(style) => style.fmt(f),
            Feature::ParameterIn(parameter_in) => parameter_in.fmt(f),
            Feature::AllowReserved(allow_reserved) => allow_reserved.fmt(f),
            Feature::Explode(explode) => explode.fmt(f),
            Feature::RenameAll(rename_all) => rename_all.fmt(f),
            Feature::ValueType(value_type) => value_type.fmt(f),
            Feature::Inline(inline) => inline.fmt(f),
            Feature::IntoParamsNames(names) => names.fmt(f),
            Feature::MultipleOf(multiple_of) => multiple_of.fmt(f),
            Feature::Maximum(maximum) => maximum.fmt(f),
            Feature::Minimum(minimum) => minimum.fmt(f),
            Feature::ExclusiveMaximum(exclusive_maximum) => exclusive_maximum.fmt(f),
            Feature::ExclusiveMinimum(exclusive_minimum) => exclusive_minimum.fmt(f),
            Feature::MaxLength(max_length) => max_length.fmt(f),
            Feature::MinLength(min_length) => min_length.fmt(f),
            Feature::Pattern(pattern) => pattern.fmt(f),
            Feature::MaxItems(max_items) => max_items.fmt(f),
            Feature::MinItems(min_items) => min_items.fmt(f),
            Feature::MaxProperties(max_properties) => max_properties.fmt(f),
            Feature::MinProperties(min_properties) => min_properties.fmt(f),
            Feature::SchemaWith(schema_with) => schema_with.fmt(f),
            Feature::Description(description) => description.fmt(f),
            Feature::Deprecated(deprecated) => deprecated.fmt(f),
            Feature::As(as_feature) => as_feature.fmt(f),
            Feature::AdditionalProperties(additional_properties) => additional_properties.fmt(f),
            Feature::Required(required) => required.fmt(f),
        }
    }
}

impl Validatable for Feature {
    fn is_validatable(&self) -> bool {
        match &self {
            Feature::Default(default) => default.is_validatable(),
            Feature::Example(example) => example.is_validatable(),
            Feature::XmlAttr(xml) => xml.is_validatable(),
            Feature::Format(format) => format.is_validatable(),
            Feature::WriteOnly(write_only) => write_only.is_validatable(),
            Feature::ReadOnly(read_only) => read_only.is_validatable(),
            Feature::Title(title) => title.is_validatable(),
            Feature::Nullable(nullable) => nullable.is_validatable(),
            Feature::Rename(rename) => rename.is_validatable(),
            Feature::Style(style) => style.is_validatable(),
            Feature::ParameterIn(parameter_in) => parameter_in.is_validatable(),
            Feature::AllowReserved(allow_reserved) => allow_reserved.is_validatable(),
            Feature::Explode(explode) => explode.is_validatable(),
            Feature::RenameAll(rename_all) => rename_all.is_validatable(),
            Feature::ValueType(value_type) => value_type.is_validatable(),
            Feature::Inline(inline) => inline.is_validatable(),
            Feature::IntoParamsNames(names) => names.is_validatable(),
            Feature::MultipleOf(multiple_of) => multiple_of.is_validatable(),
            Feature::Maximum(maximum) => maximum.is_validatable(),
            Feature::Minimum(minimum) => minimum.is_validatable(),
            Feature::ExclusiveMaximum(exclusive_maximum) => exclusive_maximum.is_validatable(),
            Feature::ExclusiveMinimum(exclusive_minimum) => exclusive_minimum.is_validatable(),
            Feature::MaxLength(max_length) => max_length.is_validatable(),
            Feature::MinLength(min_length) => min_length.is_validatable(),
            Feature::Pattern(pattern) => pattern.is_validatable(),
            Feature::MaxItems(max_items) => max_items.is_validatable(),
            Feature::MinItems(min_items) => min_items.is_validatable(),
            Feature::MaxProperties(max_properties) => max_properties.is_validatable(),
            Feature::MinProperties(min_properties) => min_properties.is_validatable(),
            Feature::SchemaWith(schema_with) => schema_with.is_validatable(),
            Feature::Description(description) => description.is_validatable(),
            Feature::Deprecated(deprecated) => deprecated.is_validatable(),
            Feature::As(as_feature) => as_feature.is_validatable(),
            Feature::AdditionalProperties(additional_properties) => {
                additional_properties.is_validatable()
            }
            Feature::Required(required) => required.is_validatable(),
        }
    }
}

macro_rules! is_validatable {
    ( $( $ident:ident => $validatable:literal ),* ) => {
        $(
            impl Validatable for $ident {
                fn is_validatable(&self) -> bool {
                    $validatable
                }
            }
        )*
    };
}

is_validatable! {
    Default => false,
    Example => false,
    XmlAttr => false,
    Format => false,
    WriteOnly => false,
    ReadOnly => false,
    Title => false,
    Nullable => false,
    Rename => false,
    Style => false,
    ParameterIn => false,
    AllowReserved => false,
    Explode => false,
    RenameAll => false,
    ValueType => false,
    Inline => false,
    Names => false,
    MultipleOf => true,
    Maximum => true,
    Minimum => true,
    ExclusiveMaximum => true,
    ExclusiveMinimum => true,
    MaxLength => true,
    MinLength => true,
    Pattern => true,
    MaxItems => true,
    MinItems => true,
    MaxProperties => false,
    MinProperties => false,
    SchemaWith => false,
    Description => false,
    Deprecated => false,
    As => false,
    AdditionalProperties => false,
    Required => false
}

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Example(AnyValue);

impl Parse for Example {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || AnyValue::parse_any(input)).map(Self)
    }
}

impl ToTokens for Example {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<Example> for Feature {
    fn from(value: Example) -> Self {
        Feature::Example(value)
    }
}

name!(Example = "example");

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Default(pub(crate) Option<AnyValue>);

impl Default {
    pub fn new_default_trait(struct_ident: Ident, field_ident: syn::Member) -> Self {
        Self(Some(AnyValue::new_default_trait(struct_ident, field_ident)))
    }
}

impl Parse for Default {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        if input.peek(syn::Token![=]) {
            parse_utils::parse_next(input, || AnyValue::parse_any(input)).map(|any| Self(Some(any)))
        } else {
            Ok(Self(None))
        }
    }
}

impl ToTokens for Default {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        match &self.0 {
            Some(inner) => tokens.extend(quote! {Some(#inner)}),
            None => tokens.extend(quote! {None}),
        }
    }
}

impl From<self::Default> for Feature {
    fn from(value: self::Default) -> Self {
        Feature::Default(value)
    }
}

name!(Default = "default");

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Inline(bool);

impl Parse for Inline {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl From<bool> for Inline {
    fn from(value: bool) -> Self {
        Inline(value)
    }
}

impl From<Inline> for Feature {
    fn from(value: Inline) -> Self {
        Feature::Inline(value)
    }
}

name!(Inline = "inline");

#[derive(Default, Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct XmlAttr(schema::xml::XmlAttr);

impl XmlAttr {
    /// Split [`XmlAttr`] for [`GenericType::Vec`] returning tuple of [`XmlAttr`]s where first
    /// one is for a vec and second one is for object field.
    pub fn split_for_vec(&mut self, type_tree: &TypeTree) -> (Option<XmlAttr>, Option<XmlAttr>) {
        if matches!(type_tree.generic_type, Some(GenericType::Vec)) {
            let mut value_xml = mem::take(self);
            let vec_xml = schema::xml::XmlAttr::with_wrapped(
                mem::take(&mut value_xml.0.is_wrapped),
                mem::take(&mut value_xml.0.wrap_name),
            );

            (Some(XmlAttr(vec_xml)), Some(value_xml))
        } else {
            self.validate_xml(&self.0);

            (None, Some(mem::take(self)))
        }
    }

    #[inline]
    fn validate_xml(&self, xml: &schema::xml::XmlAttr) {
        if let Some(wrapped_ident) = xml.is_wrapped.as_ref() {
            abort! {wrapped_ident, "cannot use `wrapped` attribute in non slice field type";
                help = "Try removing `wrapped` attribute or make your field `Vec`"
            }
        }
    }
}

impl Parse for XmlAttr {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        let xml;
        parenthesized!(xml in input);
        xml.parse::<schema::xml::XmlAttr>().map(Self)
    }
}

impl ToTokens for XmlAttr {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<XmlAttr> for Feature {
    fn from(value: XmlAttr) -> Self {
        Feature::XmlAttr(value)
    }
}

name!(XmlAttr = "xml");

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Format(SchemaFormat<'static>);

impl Parse for Format {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || input.parse::<SchemaFormat>()).map(Self)
    }
}

impl ToTokens for Format {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<Format> for Feature {
    fn from(value: Format) -> Self {
        Feature::Format(value)
    }
}

name!(Format = "format");

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct ValueType(syn::Type);

impl ValueType {
    /// Create [`TypeTree`] from current [`syn::Type`].
    pub fn as_type_tree(&self) -> TypeTree {
        TypeTree::from_type(&self.0)
    }
}

impl Parse for ValueType {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || input.parse::<syn::Type>()).map(Self)
    }
}

impl From<ValueType> for Feature {
    fn from(value: ValueType) -> Self {
        Feature::ValueType(value)
    }
}

name!(ValueType = "value_type");

#[derive(Clone, Copy)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct WriteOnly(bool);

impl Parse for WriteOnly {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for WriteOnly {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<WriteOnly> for Feature {
    fn from(value: WriteOnly) -> Self {
        Feature::WriteOnly(value)
    }
}

name!(WriteOnly = "write_only");

#[derive(Clone, Copy)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct ReadOnly(bool);

impl Parse for ReadOnly {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for ReadOnly {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<ReadOnly> for Feature {
    fn from(value: ReadOnly) -> Self {
        Feature::ReadOnly(value)
    }
}

name!(ReadOnly = "read_only");

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Title(String);

impl Parse for Title {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next_literal_str(input).map(Self)
    }
}

impl ToTokens for Title {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<Title> for Feature {
    fn from(value: Title) -> Self {
        Feature::Title(value)
    }
}

name!(Title = "title");

#[derive(Clone, Copy)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Nullable(bool);

impl Nullable {
    pub fn new() -> Self {
        Self(true)
    }
}

impl Parse for Nullable {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for Nullable {
    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<Nullable> for Feature {
    fn from(value: Nullable) -> Self {
        Feature::Nullable(value)
    }
}

name!(Nullable = "nullable");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Rename(String);

impl Rename {
    pub fn into_value(self) -> String {
        self.0
    }
}

impl Parse for Rename {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next_literal_str(input).map(Self)
    }
}

impl ToTokens for Rename {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        tokens.extend(self.0.to_token_stream())
    }
}

impl From<Rename> for Feature {
    fn from(value: Rename) -> Self {
        Feature::Rename(value)
    }
}

name!(Rename = "rename");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct RenameAll(RenameRule);

impl RenameAll {
    pub fn as_rename_rule(&self) -> &RenameRule {
        &self.0
    }
}

impl Parse for RenameAll {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        let litstr = parse_utils::parse_next(input, || input.parse::<LitStr>())?;

        litstr
            .value()
            .parse::<RenameRule>()
            .map_err(|error| syn::Error::new(litstr.span(), error.to_string()))
            .map(Self)
    }
}

impl From<RenameAll> for Feature {
    fn from(value: RenameAll) -> Self {
        Feature::RenameAll(value)
    }
}

name!(RenameAll = "rename_all");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Style(ParameterStyle);

impl From<ParameterStyle> for Style {
    fn from(style: ParameterStyle) -> Self {
        Self(style)
    }
}

impl Parse for Style {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || input.parse::<ParameterStyle>().map(Self))
    }
}

impl ToTokens for Style {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens)
    }
}

impl From<Style> for Feature {
    fn from(value: Style) -> Self {
        Feature::Style(value)
    }
}

name!(Style = "style");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct AllowReserved(bool);

impl Parse for AllowReserved {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for AllowReserved {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens)
    }
}

impl From<AllowReserved> for Feature {
    fn from(value: AllowReserved) -> Self {
        Feature::AllowReserved(value)
    }
}

name!(AllowReserved = "allow_reserved");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Explode(bool);

impl Parse for Explode {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for Explode {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens)
    }
}

impl From<Explode> for Feature {
    fn from(value: Explode) -> Self {
        Feature::Explode(value)
    }
}

name!(Explode = "explode");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct ParameterIn(parameter::ParameterIn);

impl Parse for ParameterIn {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || input.parse::<parameter::ParameterIn>().map(Self))
    }
}

impl ToTokens for ParameterIn {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<ParameterIn> for Feature {
    fn from(value: ParameterIn) -> Self {
        Feature::ParameterIn(value)
    }
}

name!(ParameterIn = "parameter_in");

/// Specify names of unnamed fields with `names(...) attribute for `IntoParams` derive.
#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Names(Vec<String>);

impl Names {
    pub fn into_values(self) -> Vec<String> {
        self.0
    }
}

impl Parse for Names {
    fn parse(input: syn::parse::ParseStream, _: Ident) -> syn::Result<Self> {
        Ok(Self(
            parse_utils::parse_punctuated_within_parenthesis::<LitStr>(input)?
                .iter()
                .map(LitStr::value)
                .collect(),
        ))
    }
}

impl From<Names> for Feature {
    fn from(value: Names) -> Self {
        Feature::IntoParamsNames(value)
    }
}

name!(Names = "names");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MultipleOf(f64, Ident);

impl Validate for MultipleOf {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`multiple_of` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-multipleof`"
            }
        };
    }
}

impl Parse for MultipleOf {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self> {
        parse_number(input).map(|multiple_of| Self(multiple_of, ident))
    }
}

impl ToTokens for MultipleOf {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MultipleOf> for Feature {
    fn from(value: MultipleOf) -> Self {
        Feature::MultipleOf(value)
    }
}

name!(MultipleOf = "multiple_of");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Maximum(f64, Ident);

impl Validate for Maximum {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`maximum` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-maximum`"
            }
        }
    }
}

impl Parse for Maximum {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|maximum| Self(maximum, ident))
    }
}

impl ToTokens for Maximum {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<Maximum> for Feature {
    fn from(value: Maximum) -> Self {
        Feature::Maximum(value)
    }
}

name!(Maximum = "maximum");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Minimum(f64, Ident);

impl Minimum {
    pub fn new(value: f64, span: Span) -> Self {
        Self(value, Ident::new("empty", span))
    }
}

impl Validate for Minimum {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`minimum` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-minimum`"
            }
        }
    }
}

impl Parse for Minimum {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|maximum| Self(maximum, ident))
    }
}

impl ToTokens for Minimum {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<Minimum> for Feature {
    fn from(value: Minimum) -> Self {
        Feature::Minimum(value)
    }
}

name!(Minimum = "minimum");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct ExclusiveMaximum(f64, Ident);

impl Validate for ExclusiveMaximum {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`exclusive_maximum` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-exclusivemaximum`"
            }
        }
    }
}

impl Parse for ExclusiveMaximum {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|max| Self(max, ident))
    }
}

impl ToTokens for ExclusiveMaximum {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<ExclusiveMaximum> for Feature {
    fn from(value: ExclusiveMaximum) -> Self {
        Feature::ExclusiveMaximum(value)
    }
}

name!(ExclusiveMaximum = "exclusive_maximum");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct ExclusiveMinimum(f64, Ident);

impl Validate for ExclusiveMinimum {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`exclusive_minimum` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-exclusiveminimum`"
            }
        }
    }
}

impl Parse for ExclusiveMinimum {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|min| Self(min, ident))
    }
}

impl ToTokens for ExclusiveMinimum {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<ExclusiveMinimum> for Feature {
    fn from(value: ExclusiveMinimum) -> Self {
        Feature::ExclusiveMinimum(value)
    }
}

name!(ExclusiveMinimum = "exclusive_minimum");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MaxLength(usize, Ident);

impl Validate for MaxLength {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`max_length` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-maxlength`"
            }
        }
    }
}

impl Parse for MaxLength {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_integer(input).map(|max_length| Self(max_length, ident))
    }
}

impl ToTokens for MaxLength {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MaxLength> for Feature {
    fn from(value: MaxLength) -> Self {
        Feature::MaxLength(value)
    }
}

name!(MaxLength = "max_length");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MinLength(usize, Ident);

impl Validate for MinLength {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`min_length` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-minlength`"
            }
        }
    }
}

impl Parse for MinLength {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_integer(input).map(|max_length| Self(max_length, ident))
    }
}

impl ToTokens for MinLength {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MinLength> for Feature {
    fn from(value: MinLength) -> Self {
        Feature::MinLength(value)
    }
}

name!(MinLength = "min_length");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Pattern(String, Ident);

impl Validate for Pattern {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`pattern` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-pattern`"
            }
        }
    }
}

impl Parse for Pattern {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_utils::parse_next(input, || input.parse::<LitStr>())
            .map(|pattern| Self(pattern.value(), ident))
    }
}

impl ToTokens for Pattern {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<Pattern> for Feature {
    fn from(value: Pattern) -> Self {
        Feature::Pattern(value)
    }
}

name!(Pattern = "pattern");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MaxItems(usize, Ident);

impl Validate for MaxItems {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`max_items` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-maxitems"
            }
        }
    }
}

impl Parse for MaxItems {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|max_items| Self(max_items, ident))
    }
}

impl ToTokens for MaxItems {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MaxItems> for Feature {
    fn from(value: MaxItems) -> Self {
        Feature::MaxItems(value)
    }
}

name!(MaxItems = "max_items");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MinItems(usize, Ident);

impl Validate for MinItems {
    fn validate(&self, validator: impl Validator) {
        if let Err(error) = validator.is_valid() {
            abort! {self.1, "`min_items` error: {}", error;
                help = "See more details: `http://json-schema.org/draft/2020-12/json-schema-validation.html#name-minitems"
            }
        }
    }
}

impl Parse for MinItems {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_number(input).map(|max_items| Self(max_items, ident))
    }
}

impl ToTokens for MinItems {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MinItems> for Feature {
    fn from(value: MinItems) -> Self {
        Feature::MinItems(value)
    }
}

name!(MinItems = "min_items");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MaxProperties(usize, Ident);

impl Parse for MaxProperties {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_integer(input).map(|max_properties| Self(max_properties, ident))
    }
}

impl ToTokens for MaxProperties {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MaxProperties> for Feature {
    fn from(value: MaxProperties) -> Self {
        Feature::MaxProperties(value)
    }
}

name!(MaxProperties = "max_properties");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct MinProperties(usize, Ident);

impl Parse for MinProperties {
    fn parse(input: ParseStream, ident: Ident) -> syn::Result<Self>
    where
        Self: Sized,
    {
        parse_integer(input).map(|min_properties| Self(min_properties, ident))
    }
}

impl ToTokens for MinProperties {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<MinProperties> for Feature {
    fn from(value: MinProperties) -> Self {
        Feature::MinProperties(value)
    }
}

name!(MinProperties = "min_properties");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct SchemaWith(TypePath);

impl Parse for SchemaWith {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self> {
        parse_utils::parse_next(input, || input.parse::<TypePath>().map(Self))
    }
}

impl ToTokens for SchemaWith {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        let path = &self.0;
        tokens.extend(quote! {
            #path()
        })
    }
}

impl From<SchemaWith> for Feature {
    fn from(value: SchemaWith) -> Self {
        Feature::SchemaWith(value)
    }
}

name!(SchemaWith = "schema_with");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Description(String);

impl Parse for Description {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized,
    {
        parse_utils::parse_next_literal_str(input).map(Self)
    }
}

impl ToTokens for Description {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens);
    }
}

impl From<String> for Description {
    fn from(value: String) -> Self {
        Self(value)
    }
}

impl From<Description> for Feature {
    fn from(value: Description) -> Self {
        Self::Description(value)
    }
}

name!(Description = "description");

/// Deprecated feature parsed from macro attributes.
///
/// This feature supports only syntax parsed from utoipa specific macro attributes, it does not
/// support Rust `#[deprecated]` attribute.
#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct Deprecated(bool);

impl Parse for Deprecated {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized,
    {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for Deprecated {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        let deprecated: crate::Deprecated = self.0.into();
        deprecated.to_tokens(tokens);
    }
}

impl From<Deprecated> for Feature {
    fn from(value: Deprecated) -> Self {
        Self::Deprecated(value)
    }
}

name!(Deprecated = "deprecated");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct As(pub TypePath);

impl Parse for As {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized,
    {
        parse_utils::parse_next(input, || input.parse()).map(Self)
    }
}

impl From<As> for Feature {
    fn from(value: As) -> Self {
        Self::As(value)
    }
}

name!(As = "as");

#[cfg_attr(feature = "debug", derive(Debug))]
#[derive(Clone)]
pub struct AdditionalProperties(bool);

impl Parse for AdditionalProperties {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized,
    {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for AdditionalProperties {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        let additional_properties = &self.0;
        tokens.extend(quote!(
            utoipa::openapi::schema::AdditionalProperties::FreeForm(
                #additional_properties
            )
        ))
    }
}

name!(AdditionalProperties = "additional_properties");

impl From<AdditionalProperties> for Feature {
    fn from(value: AdditionalProperties) -> Self {
        Self::AdditionalProperties(value)
    }
}

#[derive(Clone)]
#[cfg_attr(feature = "debug", derive(Debug))]
pub struct Required(pub bool);

impl Required {
    pub fn is_true(&self) -> bool {
        self.0
    }
}

impl Parse for Required {
    fn parse(input: ParseStream, _: Ident) -> syn::Result<Self>
    where
        Self: std::marker::Sized,
    {
        parse_utils::parse_bool_or_true(input).map(Self)
    }
}

impl ToTokens for Required {
    fn to_tokens(&self, tokens: &mut TokenStream) {
        self.0.to_tokens(tokens)
    }
}

impl From<crate::Required> for Required {
    fn from(value: crate::Required) -> Self {
        if value == crate::Required::True {
            Self(true)
        } else {
            Self(false)
        }
    }
}

impl From<bool> for Required {
    fn from(value: bool) -> Self {
        Self(value)
    }
}

impl From<Required> for Feature {
    fn from(value: Required) -> Self {
        Self::Required(value)
    }
}

name!(Required = "required");

pub trait Validator {
    fn is_valid(&self) -> Result<(), &'static str>;
}

pub struct IsNumber<'a>(pub &'a SchemaType<'a>);

impl Validator for IsNumber<'_> {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0.is_number() {
            Ok(())
        } else {
            Err("can only be used with `number` type")
        }
    }
}

pub struct IsString<'a>(&'a SchemaType<'a>);

impl Validator for IsString<'_> {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0.is_string() {
            Ok(())
        } else {
            Err("can only be used with `string` type")
        }
    }
}

pub struct IsInteger<'a>(&'a SchemaType<'a>);

impl Validator for IsInteger<'_> {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0.is_integer() {
            Ok(())
        } else {
            Err("can only be used with `integer` type")
        }
    }
}

pub struct IsVec<'a>(&'a TypeTree<'a>);

impl Validator for IsVec<'_> {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0.generic_type == Some(GenericType::Vec) {
            Ok(())
        } else {
            Err("can only be used with `Vec`, `array` or `slice` types")
        }
    }
}

pub struct AboveZeroUsize(usize);

impl Validator for AboveZeroUsize {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0 != 0 {
            Ok(())
        } else {
            Err("can only be above zero value")
        }
    }
}

pub struct AboveZeroF64(f64);

impl Validator for AboveZeroF64 {
    fn is_valid(&self) -> Result<(), &'static str> {
        if self.0 > 0.0 {
            Ok(())
        } else {
            Err("can only be above zero value")
        }
    }
}

pub struct ValidatorChain<'c> {
    inner: &'c dyn Validator,
    next: Option<&'c dyn Validator>,
}

impl Validator for ValidatorChain<'_> {
    fn is_valid(&self) -> Result<(), &'static str> {
        self.inner.is_valid().and_then(|_| {
            if let Some(validator) = self.next.as_ref() {
                validator.is_valid()
            } else {
                // if there is no next validator consider it valid
                Ok(())
            }
        })
    }
}

impl<'c> ValidatorChain<'c> {
    pub fn new(validator: &'c dyn Validator) -> Self {
        Self {
            inner: validator,
            next: None,
        }
    }

    pub fn next(mut self, validator: &'c dyn Validator) -> Self {
        self.next = Some(validator);

        self
    }
}

macro_rules! parse_features {
    ($ident:ident as $( $feature:path ),*) => {
        {
            fn parse(input: syn::parse::ParseStream) -> syn::Result<Vec<crate::component::features::Feature>> {
                let names = [$( <crate::component::features::parse_features!(@as_ident $feature) as crate::component::features::Name>::get_name(), )* ];
                let mut features = Vec::<crate::component::features::Feature>::new();
                let attributes = names.join(", ");

                while !input.is_empty() {
                    let ident = input.parse::<syn::Ident>().or_else(|_| {
                        input.parse::<syn::Token![as]>().map(|as_| syn::Ident::new("as", as_.span))
                    }).map_err(|error| {
                        syn::Error::new(
                            error.span(),
                            format!("unexpected attribute, expected any of: {attributes}, {error}"),
                        )
                    })?;
                    let name = &*ident.to_string();

                    $(
                        if name == <crate::component::features::parse_features!(@as_ident $feature) as crate::component::features::Name>::get_name() {
                            features.push(<$feature as crate::component::features::Parse>::parse(input, ident)?.into());
                            if !input.is_empty() {
                                input.parse::<syn::Token![,]>()?;
                            }
                            continue;
                        }
                    )*

                    if !names.contains(&name) {
                        return Err(syn::Error::new(ident.span(), format!("unexpected attribute: {name}, expected any of: {attributes}")))
                    }
                }

                Ok(features)
            }

            parse($ident)?
        }
    };
    (@as_ident $( $tt:tt )* ) => {
        $( $tt )*
    }
}

pub(crate) use parse_features;

pub trait IsInline {
    fn is_inline(&self) -> bool;
}

impl IsInline for Vec<Feature> {
    fn is_inline(&self) -> bool {
        self.iter()
            .find_map(|feature| match feature {
                Feature::Inline(inline) if inline.0 => Some(inline),
                _ => None,
            })
            .is_some()
    }
}

pub trait ToTokensExt {
    fn to_token_stream(&self) -> TokenStream;
}

impl ToTokensExt for Vec<Feature> {
    fn to_token_stream(&self) -> TokenStream {
        self.iter().fold(TokenStream::new(), |mut tokens, item| {
            item.to_tokens(&mut tokens);
            tokens
        })
    }
}

pub trait FeaturesExt {
    fn pop_by(&mut self, op: impl FnMut(&Feature) -> bool) -> Option<Feature>;

    fn pop_value_type_feature(&mut self) -> Option<super::features::ValueType>;

    /// Pop [`Rename`] feature if exists in [`Vec<Feature>`] list.
    fn pop_rename_feature(&mut self) -> Option<Rename>;

    /// Pop [`RenameAll`] feature if exists in [`Vec<Feature>`] list.
    fn pop_rename_all_feature(&mut self) -> Option<RenameAll>;

    /// Extract [`XmlAttr`] feature for given `type_tree` if it has generic type [`GenericType::Vec`]
    fn extract_vec_xml_feature(&mut self, type_tree: &TypeTree) -> Option<Feature>;
}

impl FeaturesExt for Vec<Feature> {
    fn pop_by(&mut self, op: impl FnMut(&Feature) -> bool) -> Option<Feature> {
        self.iter()
            .position(op)
            .map(|index| self.swap_remove(index))
    }

    fn pop_value_type_feature(&mut self) -> Option<super::features::ValueType> {
        self.pop_by(|feature| matches!(feature, Feature::ValueType(_)))
            .and_then(|feature| match feature {
                Feature::ValueType(value_type) => Some(value_type),
                _ => None,
            })
    }

    fn pop_rename_feature(&mut self) -> Option<Rename> {
        self.pop_by(|feature| matches!(feature, Feature::Rename(_)))
            .and_then(|feature| match feature {
                Feature::Rename(rename) => Some(rename),
                _ => None,
            })
    }

    fn pop_rename_all_feature(&mut self) -> Option<RenameAll> {
        self.pop_by(|feature| matches!(feature, Feature::RenameAll(_)))
            .and_then(|feature| match feature {
                Feature::RenameAll(rename_all) => Some(rename_all),
                _ => None,
            })
    }

    fn extract_vec_xml_feature(&mut self, type_tree: &TypeTree) -> Option<Feature> {
        self.iter_mut().find_map(|feature| match feature {
            Feature::XmlAttr(xml_feature) => {
                let (vec_xml, value_xml) = xml_feature.split_for_vec(type_tree);

                // replace the original xml attribute with splitted value xml
                if let Some(mut xml) = value_xml {
                    mem::swap(xml_feature, &mut xml)
                }

                vec_xml.map(Feature::XmlAttr)
            }
            _ => None,
        })
    }
}

impl FeaturesExt for Option<Vec<Feature>> {
    fn pop_by(&mut self, op: impl FnMut(&Feature) -> bool) -> Option<Feature> {
        self.as_mut().and_then(|features| features.pop_by(op))
    }

    fn pop_value_type_feature(&mut self) -> Option<super::features::ValueType> {
        self.as_mut()
            .and_then(|features| features.pop_value_type_feature())
    }

    fn pop_rename_feature(&mut self) -> Option<Rename> {
        self.as_mut()
            .and_then(|features| features.pop_rename_feature())
    }

    fn pop_rename_all_feature(&mut self) -> Option<RenameAll> {
        self.as_mut()
            .and_then(|features| features.pop_rename_all_feature())
    }

    fn extract_vec_xml_feature(&mut self, type_tree: &TypeTree) -> Option<Feature> {
        self.as_mut()
            .and_then(|features| features.extract_vec_xml_feature(type_tree))
    }
}

macro_rules! pop_feature {
    ($features:ident => $value:pat_param) => {{
        $features.pop_by(|feature| matches!(feature, $value))
    }};
}

pub(crate) use pop_feature;

macro_rules! pop_feature_as_inner {
    ( $features:ident => $($value:tt)* ) => {
        crate::component::features::pop_feature!($features => $( $value )* )
            .map(|f| match f {
                $( $value )* => {
                    crate::component::features::pop_feature_as_inner!( @as_value $( $value )* )
                },
                _ => unreachable!()
            })
    };
    ( @as_value $tt:tt :: $tr:tt ( $v:tt ) ) => {
        $v
    }
}

pub(crate) use pop_feature_as_inner;

pub trait IntoInner<T> {
    fn into_inner(self) -> T;
}

macro_rules! impl_into_inner {
    ($ident:ident) => {
        impl crate::component::features::IntoInner<Vec<Feature>> for $ident {
            fn into_inner(self) -> Vec<Feature> {
                self.0
            }
        }

        impl crate::component::features::IntoInner<Option<Vec<Feature>>> for Option<$ident> {
            fn into_inner(self) -> Option<Vec<Feature>> {
                self.map(crate::component::features::IntoInner::into_inner)
            }
        }
    };
}

pub(crate) use impl_into_inner;

pub trait Merge<T>: IntoInner<Vec<Feature>> {
    fn merge(self, from: T) -> Self;
}

macro_rules! impl_merge {
    ( $($ident:ident),* ) => {
        $(
            impl AsMut<Vec<Feature>> for $ident {
                fn as_mut(&mut self) -> &mut Vec<Feature> {
                    &mut self.0
                }
            }

            impl crate::component::features::Merge<$ident> for $ident {
                fn merge(mut self, from: $ident) -> Self {
                    let a = self.as_mut();
                    let mut b = from.into_inner();

                    a.append(&mut b);

                    self
                }
            }
        )*
    };
}

pub(crate) use impl_merge;

impl IntoInner<Vec<Feature>> for Vec<Feature> {
    fn into_inner(self) -> Vec<Feature> {
        self
    }
}

impl Merge<Vec<Feature>> for Vec<Feature> {
    fn merge(mut self, mut from: Vec<Feature>) -> Self {
        self.append(&mut from);
        self
    }
}