use crate::{AsgConvertError, ConstValue, Expression, ExpressionNode, FromAst, Node, PartialType, Scope, Span, Type};
use leo_ast::IntegerType;
use std::cell::Cell;
#[derive(Clone)]
pub struct ArrayAccessExpression<'a> {
pub parent: Cell<Option<&'a Expression<'a>>>,
pub span: Option<Span>,
pub array: Cell<&'a Expression<'a>>,
pub index: Cell<&'a Expression<'a>>,
}
impl<'a> Node for ArrayAccessExpression<'a> {
fn span(&self) -> Option<&Span> {
self.span.as_ref()
}
}
impl<'a> ExpressionNode<'a> for ArrayAccessExpression<'a> {
fn set_parent(&self, parent: &'a Expression<'a>) {
self.parent.replace(Some(parent));
}
fn get_parent(&self) -> Option<&'a Expression<'a>> {
self.parent.get()
}
fn enforce_parents(&self, expr: &'a Expression<'a>) {
self.array.get().set_parent(expr);
self.index.get().set_parent(expr);
}
fn get_type(&self) -> Option<Type<'a>> {
match self.array.get().get_type() {
Some(Type::Array(element, _)) => Some(*element),
_ => None,
}
}
fn is_mut_ref(&self) -> bool {
self.array.get().is_mut_ref()
}
fn const_value(&self) -> Option<ConstValue<'a>> {
let mut array = match self.array.get().const_value()? {
ConstValue::Array(values) => values,
_ => return None,
};
let const_index = match self.index.get().const_value()? {
ConstValue::Int(x) => x.to_usize()?,
_ => return None,
};
if const_index >= array.len() {
return None;
}
Some(array.remove(const_index))
}
fn is_consty(&self) -> bool {
self.array.get().is_consty()
}
}
impl<'a> FromAst<'a, leo_ast::ArrayAccessExpression> for ArrayAccessExpression<'a> {
fn from_ast(
scope: &'a Scope<'a>,
value: &leo_ast::ArrayAccessExpression,
expected_type: Option<PartialType<'a>>,
) -> Result<ArrayAccessExpression<'a>, AsgConvertError> {
let array = <&Expression<'a>>::from_ast(
scope,
&*value.array,
Some(PartialType::Array(expected_type.map(Box::new), None)),
)?;
let array_len = match array.get_type() {
Some(Type::Array(_, len)) => len,
type_ => {
return Err(AsgConvertError::unexpected_type(
"array",
type_.map(|x| x.to_string()).as_deref(),
&value.span,
));
}
};
let index = <&Expression<'a>>::from_ast(
scope,
&*value.index,
Some(PartialType::Integer(None, Some(IntegerType::U32))),
)?;
if let Some(index) = index
.const_value()
.map(|x| x.int().map(|x| x.to_usize()).flatten())
.flatten()
{
if index >= array_len {
return Err(AsgConvertError::array_index_out_of_bounds(
index,
&array.span().cloned().unwrap_or_default(),
));
}
}
Ok(ArrayAccessExpression {
parent: Cell::new(None),
span: Some(value.span.clone()),
array: Cell::new(array),
index: Cell::new(index),
})
}
}
impl<'a> Into<leo_ast::ArrayAccessExpression> for &ArrayAccessExpression<'a> {
fn into(self) -> leo_ast::ArrayAccessExpression {
leo_ast::ArrayAccessExpression {
array: Box::new(self.array.get().into()),
index: Box::new(self.index.get().into()),
span: self.span.clone().unwrap_or_default(),
}
}
}