use std::collections::HashMap;

pub struct Ast {
    program: Vec<Statement>,
}

pub enum Statement {
    Open(String), // TODO: parse into `OpenTree`
    Definition {
        is_public: bool,
        ident: String,
        generics: Vec<Expression>, // TODO: refine
        definition_kind: crate::token::Kind,
        definition: Expression,
    },
    Module {
        is_public: bool,
        ident: String,
        definition: Vec<Statement>,
    },
    Comment(String), // TODO: differentiate kinds
}

pub enum Expression {
    Function {
        args: Vec<Expression>, // TODO: get more granular
        body: Vec<Statement>,
    },
    Application {
        function: Box<Expression>,
        args: Vec<Expression>,
    },
    BinOp {
        operands: Box<(Expression, Expression)>,
        operator: Box<Expression>, // TODO: refine? (maybe we _want_ arbitrary binary operators)
    },
    Type(Vec<Type>),
    GenericSpecification(Vec<Expression>), // TODO: refine
}

pub enum Type {
    Record(HashMap<String, String>), // { red: u8, green: u8, blue: u8 }
    Tuple(Vec<String>),              // `Some (T) | None`
    Simple(String),                  // `Option::Some (T)`
    Empty,                           // `Option::None`
}