use crate::instruction::{AddOperand, MultiplyOperand, SubtractOperand};
use crate::vm::CallFrame;
use crate::vm::constant::Constant;
use crate::vm::value::Value;
use crate::vm::value_util::{load_constant_value, load_value};
use std::collections::HashMap;
use std::rc::Rc;

pub fn add_operand_to_value(
    add_operand: &AddOperand,
    registers: &[Value],
    current_frame: &CallFrame,
    constants: &HashMap<Rc<str>, Constant>,
) -> Value {
    match add_operand {
        AddOperand::Location(location) => load_value(
            registers,
            current_frame.stack(),
            current_frame.fp(),
            location,
        )
        .clone(),
        AddOperand::Int(i) => Value::Int(*i),
        AddOperand::Double(d) => Value::Double(*d),
        AddOperand::String(constant_name) => load_constant_value(constants, constant_name),
    }
}

pub fn subtract_operand_to_value(
    subtract_operand: &SubtractOperand,
    registers: &[Value],
    current_frame: &CallFrame,
) -> Value {
    match subtract_operand {
        SubtractOperand::Location(location) => load_value(
            registers,
            current_frame.stack(),
            current_frame.fp(),
            location,
        )
        .clone(),
        SubtractOperand::Int(i) => Value::Int(*i),
        SubtractOperand::Double(d) => Value::Double(*d),
    }
}

pub fn multiply_operand_to_value(
    multiply_operand: &MultiplyOperand,
    registers: &[Value],
    current_frame: &CallFrame,
) -> Value {
    match multiply_operand {
        MultiplyOperand::Location(location) => load_value(
            registers,
            current_frame.stack(),
            current_frame.fp(),
            location,
        )
        .clone(),
        MultiplyOperand::Int(i) => Value::Int(*i),
        MultiplyOperand::Double(d) => Value::Double(*d),
    }
}