use crate::{BytecodeReader, Mutation, Step, Value};

impl<'gc> crate::Vm<'gc> {
    #[inline(always)]
    pub(crate) fn op_load_local(&mut self, reader: &mut BytecodeReader<'_>) -> Step {
        let idx = reader.read_u32() as usize;
        self.push(self.env.borrow().locals[idx]);
        Step::Continue(())
    }

    #[inline(always)]
    pub(crate) fn op_load_outer(&mut self, reader: &mut BytecodeReader<'_>) -> Step {
        let layer = reader.read_u8();
        let idx = reader.read_u32() as usize;
        let mut cur = self.env;
        for _ in 0..layer {
            let prev = cur.borrow().prev.expect("LoadOuter: env chain too short");
            cur = prev;
        }
        let val = cur.borrow().locals[idx];
        self.push(val);
        Step::Continue(())
    }

    #[inline(always)]
    pub(crate) fn op_store_local(
        &mut self,
        reader: &mut BytecodeReader<'_>,
        mc: &Mutation<'gc>,
    ) -> Step {
        let idx = reader.read_u32() as usize;
        let val = self.pop();
        self.env.borrow_mut(mc).locals[idx] = val;
        Step::Continue(())
    }

    #[inline(always)]
    pub(crate) fn op_alloc_locals(
        &mut self,
        reader: &mut BytecodeReader<'_>,
        mc: &Mutation<'gc>,
    ) -> Step {
        let count = reader.read_u32() as usize;
        self.env
            .borrow_mut(mc)
            .locals
            .extend(std::iter::repeat_n(Value::default(), count));
        Step::Continue(())
    }
}