use std::fmt::{Debug, Display, Formatter, Result as FmtResult};

use derive_more::{Constructor, IsVariant, Unwrap};
use rpds::{HashTrieMapSync, VectorSync};

use super::common::*;

mod cnst;

pub use cnst::Const;

#[derive(Constructor, Clone, PartialEq)]
pub struct AttrSet {
    data: HashTrieMapSync<Symbol, Value>,
}

impl Debug for AttrSet {
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
        use Value::*;
        write!(f, "{{ ")?;
        for (k, v) in self.data.iter() {
            match v {
                List(_) => write!(f, "{k:?} = [ ... ]; ")?,
                AttrSet(_) => write!(f, "{k:?} = {{ ... }}; ")?,
                v => write!(f, "{k:?} = {v:?}; ")?,
            }
        }
        write!(f, "}}")
    }
}

impl Display for AttrSet {
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
        write!(f, "{{ ")?;
        for (k, v) in self.data.iter() {
            write!(f, "{k} = {v}; ")?;
        }
        write!(f, "}}")
    }
}

#[derive(Constructor, Clone, Debug, PartialEq)]
pub struct List {
    data: VectorSync<Value>,
}

impl Display for List {
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
        write!(f, "[ ")?;
        for v in self.data.iter() {
            write!(f, "{v} ")?;
        }
        write!(f, "]")
    }
}

#[derive(IsVariant, Unwrap, Clone, Debug, PartialEq)]
pub enum Value {
    Const(Const),
    AttrSet(AttrSet),
    List(List),
    Catchable(Catchable),
    Thunk,
    Func,
    PrimOp(&'static str),
    PartialPrimOp(&'static str),
}

impl Display for Value {
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
        use Value::*;
        match self {
            Const(x) => write!(f, "{x}"),
            AttrSet(x) => write!(f, "{x}"),
            List(x) => write!(f, "{x}"),
            Catchable(x) => write!(f, "{x}"),
            Thunk => write!(f, "<CODE>"),
            Func => write!(f, "<LAMBDA>"),
            PrimOp(x) => write!(f, "<PRIMOP {x}>"),
            PartialPrimOp(x) => write!(f, "<PARTIAL PRIMOP {x}>"),
        }
    }
}