package core

import (
	"git.akyoto.dev/cli/q/src/asm"
	"git.akyoto.dev/cli/q/src/ast"
	"git.akyoto.dev/cli/q/src/errors"
	"git.akyoto.dev/cli/q/src/x64"
)

// CompileAssignDivision compiles an assign statement that has quotient and remainder on the left side and division on the right.
func (f *Function) CompileAssignDivision(node *ast.Assign) error {
	left := node.Expression.Children[0]
	right := node.Expression.Children[1]

	quotient := left.Children[0]
	name := quotient.Token.Text(f.File.Bytes)
	quotientVariable := f.VariableByName(name)

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

	remainder := left.Children[1]
	name = remainder.Token.Text(f.File.Bytes)
	remainderVariable := f.VariableByName(name)

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

	dividend := right.Children[0]
	_, dividendRegister, isTemporary, err := f.Evaluate(dividend)

	if err != nil {
		return err
	}

	divisor := right.Children[1]
	err = f.Execute(right.Token, dividendRegister, divisor)
	f.RegisterRegister(asm.MOVE, quotientVariable.Register, x64.RAX)
	f.RegisterRegister(asm.MOVE, remainderVariable.Register, x64.RDX)

	if isTemporary {
		f.FreeRegister(dividendRegister)
	}

	return err
}