package core

import (
	"git.urbach.dev/cli/q/src/asm"
	"git.urbach.dev/cli/q/src/errors"
	"git.urbach.dev/cli/q/src/expression"
)

// MultiAssign assigns multiple return values to local variables.
func (f *Function) MultiAssign(left *expression.Expression, right *expression.Expression) error {
	count := 0
	_, err := f.CompileCall(right)

	if err != nil {
		return err
	}

	return left.EachLeaf(func(leaf *expression.Expression) error {
		name := leaf.Token.Text(f.File.Bytes)
		variable := f.VariableByName(name)

		if variable == nil {
			return errors.New(&errors.UnknownIdentifier{Name: name}, f.File, left.Token.Position)
		}

		f.RegisterRegister(asm.MOVE, variable.Value.Register, f.CPU.Output[count])
		f.UseVariable(variable)
		count++
		return nil
	})
}