use darling::ast::{Data, Fields};
use darling::util::Ignored;
use darling::{FromDeriveInput, FromField, FromMeta, FromVariant};
use syn::{Attribute, Generics, Ident, Lit, LitStr, Meta, Type, Visibility};

#[derive(FromMeta)]
#[darling(default)]
pub struct CacheControl {
    public: bool,
    private: bool,
    pub max_age: usize,
}

impl Default for CacheControl {
    fn default() -> Self {
        Self {
            public: true,
            private: false,
            max_age: 0,
        }
    }
}

impl CacheControl {
    pub fn is_public(&self) -> bool {
        !self.private && self.public
    }
}

#[derive(Debug)]
pub enum DefaultValue {
    Default,
    Value(Lit),
}

impl FromMeta for DefaultValue {
    fn from_word() -> darling::Result<Self> {
        Ok(DefaultValue::Default)
    }

    fn from_value(value: &Lit) -> darling::Result<Self> {
        Ok(DefaultValue::Value(value.clone()))
    }
}

#[derive(FromField)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct SimpleObjectField {
    pub ident: Option<Ident>,
    pub ty: Type,
    pub vis: Visibility,
    pub attrs: Vec<Attribute>,

    #[darling(default)]
    pub skip: bool,
    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub deprecation: Option<String>,
    #[darling(default)]
    pub owned: bool,
    #[darling(default)]
    pub cache_control: CacheControl,
    #[darling(default)]
    pub external: bool,
    #[darling(default)]
    pub provides: Option<String>,
    #[darling(default)]
    pub requires: Option<String>,
    #[darling(default)]
    pub guard: Option<Meta>,
    #[darling(default)]
    pub post_guard: Option<Meta>,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct SimpleObject {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<Ignored, SimpleObjectField>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub cache_control: CacheControl,
    #[darling(default)]
    pub extends: bool,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct Argument {
    pub name: Option<String>,
    pub desc: Option<String>,
    pub default: Option<DefaultValue>,
    pub default_with: Option<LitStr>,
    pub validator: Option<Meta>,
    pub key: bool, // for entity
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct Object {
    pub internal: bool,
    pub name: Option<String>,
    pub cache_control: CacheControl,
    pub extends: bool,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct ObjectField {
    pub skip: bool,
    pub entity: bool,
    pub name: Option<String>,
    pub deprecation: Option<String>,
    pub cache_control: CacheControl,
    pub external: bool,
    pub provides: Option<String>,
    pub requires: Option<String>,
    pub guard: Option<Meta>,
    pub post_guard: Option<Meta>,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct Enum {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<EnumItem, Ignored>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub remote: Option<String>,
}

#[derive(FromVariant)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct EnumItem {
    pub ident: Ident,
    pub attrs: Vec<Attribute>,
    pub fields: Fields<Ignored>,

    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub deprecation: Option<String>,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct Union {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<UnionItem, Ignored>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
}

#[derive(FromVariant)]
#[darling(attributes(graphql))]
pub struct UnionItem {
    pub ident: Ident,
    pub fields: Fields<syn::Type>,

    #[darling(default)]
    pub flatten: bool,
}

#[derive(FromField)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct InputObjectField {
    pub ident: Option<Ident>,
    pub ty: Type,
    pub vis: Visibility,
    pub attrs: Vec<Attribute>,

    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub default: Option<DefaultValue>,
    #[darling(default)]
    pub default_with: Option<LitStr>,
    #[darling(default)]
    pub validator: Option<Meta>,
    #[darling(default)]
    pub flatten: bool,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct InputObject {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<Ignored, InputObjectField>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
}

#[derive(FromMeta)]
pub struct InterfaceFieldArgument {
    pub name: String,
    #[darling(default)]
    pub desc: Option<String>,
    #[darling(rename = "type")]
    pub ty: LitStr,
    #[darling(default)]
    pub default: Option<DefaultValue>,
    #[darling(default)]
    pub default_with: Option<LitStr>,
}

#[derive(FromMeta)]
pub struct InterfaceField {
    pub name: String,
    #[darling(rename = "type")]
    pub ty: LitStr,
    #[darling(default)]
    pub method: Option<String>,
    #[darling(default)]
    pub desc: Option<String>,
    #[darling(default, multiple, rename = "arg")]
    pub args: Vec<InterfaceFieldArgument>,
    #[darling(default)]
    pub deprecation: Option<String>,
    #[darling(default)]
    pub external: bool,
    #[darling(default)]
    pub provides: Option<String>,
    #[darling(default)]
    pub requires: Option<String>,
}

#[derive(FromVariant)]
pub struct InterfaceMember {
    pub ident: Ident,
    pub fields: Fields<syn::Type>,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct Interface {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<InterfaceMember, Ignored>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
    #[darling(default, multiple, rename = "field")]
    pub fields: Vec<InterfaceField>,
    #[darling(default)]
    pub extends: bool,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct Scalar {
    pub internal: bool,
    pub name: Option<String>,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct Subscription {
    pub internal: bool,
    pub name: Option<String>,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct SubscriptionFieldArgument {
    pub name: Option<String>,
    pub desc: Option<String>,
    pub default: Option<DefaultValue>,
    pub default_with: Option<LitStr>,
    pub validator: Option<Meta>,
}

#[derive(FromMeta, Default)]
#[darling(default)]
pub struct SubscriptionField {
    pub skip: bool,
    pub name: Option<String>,
    pub deprecation: Option<String>,
    pub guard: Option<Meta>,
    pub post_guard: Option<Meta>,
}

#[derive(FromMeta, Default)]
#[darling(default, allow_unknown_fields)]
pub struct SubscriptionFieldWrapper {
    pub graphql: SubscriptionField,
}

#[derive(FromField)]
pub struct MergedObjectField {
    pub ident: Option<Ident>,
    pub ty: Type,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct MergedObject {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<Ignored, MergedObjectField>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
    #[darling(default)]
    pub cache_control: CacheControl,
    #[darling(default)]
    pub extends: bool,
}

#[derive(FromField)]
pub struct MergedSubscriptionField {
    pub ident: Option<Ident>,
    pub ty: Type,
}

#[derive(FromDeriveInput)]
#[darling(attributes(graphql), forward_attrs(doc))]
pub struct MergedSubscription {
    pub ident: Ident,
    pub generics: Generics,
    pub attrs: Vec<Attribute>,
    pub data: Data<Ignored, MergedSubscriptionField>,

    #[darling(default)]
    pub internal: bool,
    #[darling(default)]
    pub name: Option<String>,
}