use std::borrow::Cow;

use serde::{de::DeserializeOwned, Deserialize, Deserializer, Serialize, Serializer};
use serde_json::Value;

use crate::{
    registry::{MetaSchema, MetaSchemaRef},
    types::{ParseError, ParseFromJSON, ParseFromXML, ParseResult, ToJSON, ToXML, Type},
};

/// A any type.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
pub struct Any<T>(pub T);

impl<T: Send + Sync> Type for Any<T> {
    const IS_REQUIRED: bool = true;

    type RawValueType = T;

    type RawElementValueType = T;

    fn name() -> Cow<'static, str> {
        "any".into()
    }

    fn schema_ref() -> MetaSchemaRef {
        MetaSchemaRef::Inline(Box::new(MetaSchema::ANY))
    }

    fn as_raw_value(&self) -> Option<&Self::RawValueType> {
        Some(&self.0)
    }

    fn raw_element_iter<'a>(
        &'a self,
    ) -> Box<dyn Iterator<Item = &'a Self::RawElementValueType> + 'a> {
        Box::new(self.as_raw_value().into_iter())
    }
}

impl<T: DeserializeOwned + Send + Sync> ParseFromJSON for Any<T> {
    fn parse_from_json(value: Option<Value>) -> ParseResult<Self> {
        Ok(Self(
            serde_json::from_value(value.unwrap_or_default()).map_err(ParseError::custom)?,
        ))
    }
}

impl<T: Serialize + Send + Sync> ToJSON for Any<T> {
    fn to_json(&self) -> Option<Value> {
        Some(serde_json::to_value(&self.0).unwrap_or_default())
    }
}

impl<T: DeserializeOwned + Send + Sync> ParseFromXML for Any<T> {
    fn parse_from_xml(value: Option<Value>) -> ParseResult<Self> {
        Ok(Self(
            serde_json::from_value(value.unwrap_or_default()).map_err(ParseError::custom)?,
        ))
    }
}

impl<T: Serialize + Send + Sync> ToXML for Any<T> {
    fn to_xml(&self) -> Option<Value> {
        Some(serde_json::to_value(&self.0).unwrap_or_default())
    }
}

impl<T: Serialize> Serialize for Any<T> {
    #[inline]
    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: Serializer,
    {
        self.0.serialize(serializer)
    }
}

impl<'de, T: DeserializeOwned> Deserialize<'de> for Any<T> {
    #[inline]
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: Deserializer<'de>,
    {
        T::deserialize(deserializer).map(Self)
    }
}

impl Type for Value {
    const IS_REQUIRED: bool = true;

    type RawValueType = Self;

    type RawElementValueType = Self;

    fn name() -> Cow<'static, str> {
        "any".into()
    }

    fn schema_ref() -> MetaSchemaRef {
        MetaSchemaRef::Inline(Box::new(MetaSchema::ANY))
    }

    fn as_raw_value(&self) -> Option<&Self::RawValueType> {
        Some(self)
    }

    fn raw_element_iter<'a>(
        &'a self,
    ) -> Box<dyn Iterator<Item = &'a Self::RawElementValueType> + 'a> {
        Box::new(self.as_raw_value().into_iter())
    }
}

impl ParseFromJSON for Value {
    fn parse_from_json(value: Option<Value>) -> ParseResult<Self> {
        Ok(value.unwrap_or_default())
    }
}

impl ToJSON for Value {
    fn to_json(&self) -> Option<Value> {
        Some(self.clone())
    }
}

impl ParseFromXML for Value {
    fn parse_from_xml(value: Option<Value>) -> ParseResult<Self> {
        Ok(value.unwrap_or_default())
    }
}

impl ToXML for Value {
    fn to_xml(&self) -> Option<Value> {
        Some(self.clone())
    }
}
