package core

import (
	"fmt"

	"git.akyoto.dev/cli/q/src/build/asm"
	"git.akyoto.dev/cli/q/src/build/ast"
)

// CompileSwitch compiles a multi-branch instruction.
func (f *Function) CompileSwitch(s *ast.Switch) error {
	f.count.multiBranch++
	end := fmt.Sprintf("%s_switch_%d_end", f.UniqueName, f.count.multiBranch)

	for _, branch := range s.Cases {
		if branch.Condition == nil {
			f.PushScope(branch.Body, f.File.Bytes)
			err := f.CompileAST(branch.Body)

			if err != nil {
				return err
			}

			f.PopScope()
			break
		}

		f.count.branch++

		var (
			success = fmt.Sprintf("%s_case_%d_true", f.UniqueName, f.count.branch)
			fail    = fmt.Sprintf("%s_case_%d_false", f.UniqueName, f.count.branch)
			err     = f.CompileCondition(branch.Condition, success, fail)
		)

		if err != nil {
			return err
		}

		f.AddLabel(success)
		f.PushScope(branch.Body, f.File.Bytes)
		err = f.CompileAST(branch.Body)

		if err != nil {
			return err
		}

		f.Jump(asm.JUMP, end)
		f.PopScope()
		f.AddLabel(fail)
	}

	f.AddLabel(end)
	return nil
}