use std::fmt::Display;

use crate::ser::NetworkReadExt;

use super::{Read, ReadingError};
use serde::de::{self, DeserializeSeed, SeqAccess};

pub struct Deserializer<R: Read> {
    inner: R,
}

impl de::Error for ReadingError {
    fn custom<T: Display>(msg: T) -> Self {
        Self::Message(msg.to_string())
    }
}

impl<R: Read> Deserializer<R> {
    pub fn new(read: R) -> Self {
        Self { inner: read }
    }
}

impl<'de, R: Read> de::Deserializer<'de> for &mut Deserializer<R> {
    type Error = ReadingError;

    fn deserialize_any<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!(
            "This is impossible to do, since you cannot infer the data structure from the packet"
        )
    }

    fn deserialize_bool<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_bool(self.inner.get_bool()?)
    }

    fn deserialize_i8<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_i8(self.inner.get_i8_be()?)
    }

    fn deserialize_i16<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_i16(self.inner.get_i16_be()?)
    }

    fn deserialize_i32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_i32(self.inner.get_i32_be()?)
    }

    fn deserialize_i64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_i64(self.inner.get_i64_be()?)
    }

    fn deserialize_u8<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_u8(self.inner.get_u8_be()?)
    }

    fn deserialize_u16<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_u16(self.inner.get_u16_be()?)
    }

    fn deserialize_u32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_u32(self.inner.get_u32_be()?)
    }

    fn deserialize_u64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_u64(self.inner.get_u64_be()?)
    }

    fn deserialize_f32<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_f32(self.inner.get_f32_be()?)
    }

    fn deserialize_f64<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_f64(self.inner.get_f64_be()?)
    }

    fn deserialize_char<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_str<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        self.deserialize_string(visitor)
    }

    fn deserialize_string<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        visitor.visit_str(&self.inner.get_string()?)
    }

    fn deserialize_bytes<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_byte_buf<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_option<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        if self.inner.get_bool()? {
            visitor.visit_some(self)
        } else {
            visitor.visit_none()
        }
    }

    fn deserialize_unit<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_unit_struct<V>(
        self,
        _name: &'static str,
        _visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_newtype_struct<V>(
        self,
        _name: &'static str,
        _visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        struct Access<'a, R: Read> {
            deserializer: &'a mut Deserializer<R>,
        }

        impl<'de, R: Read> SeqAccess<'de> for Access<'_, R> {
            type Error = ReadingError;

            fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
            where
                T: de::DeserializeSeed<'de>,
            {
                let value = DeserializeSeed::deserialize(seed, &mut *self.deserializer)?;
                Ok(Some(value))
            }
        }

        visitor.visit_seq(Access { deserializer: self })
    }

    fn deserialize_tuple<V>(self, len: usize, visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        struct Access<'a, R: Read> {
            deserializer: &'a mut Deserializer<R>,
            len: usize,
        }

        impl<'de, R: Read> SeqAccess<'de> for Access<'_, R> {
            type Error = ReadingError;

            fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>, Self::Error>
            where
                T: de::DeserializeSeed<'de>,
            {
                if self.len > 0 {
                    self.len -= 1;
                    let value = DeserializeSeed::deserialize(seed, &mut *self.deserializer)?;
                    Ok(Some(value))
                } else {
                    Ok(None)
                }
            }
        }

        visitor.visit_seq(Access {
            deserializer: self,
            len,
        })
    }

    fn deserialize_tuple_struct<V>(
        self,
        _name: &'static str,
        _len: usize,
        _visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_map<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_struct<V>(
        self,
        _name: &'static str,
        fields: &'static [&'static str],
        visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        self.deserialize_tuple(fields.len(), visitor)
    }

    fn deserialize_enum<V>(
        self,
        _name: &'static str,
        _variants: &'static [&'static str],
        _visitor: V,
    ) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_identifier<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }

    fn deserialize_ignored_any<V>(self, _visitor: V) -> Result<V::Value, Self::Error>
    where
        V: de::Visitor<'de>,
    {
        unimplemented!()
    }
}