package caddyhugo

import (
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"sync"
)

type HugoInteractor interface {
	Render(srcdir, workdir string) HugoRenderer
}

type HugoRenderer interface {
	Start() error
	Stop() error
}

type HugoCmdRenderer struct {
	SrcDir   string
	TmpDir   string
	Filename string

	cmd *exec.Cmd
	mtx sync.Mutex
}

func (hcr *HugoCmdRenderer) Render(contents string) error {
	err := ioutil.WriteFile(hcr.Filename, []byte(contents), 0644)
	return err
}

func (hcr *HugoCmdRenderer) Start() error {
	hcr.mtx.Lock()
	defer hcr.mtx.Unlock()

	hcr.cmd = exec.Command("hugo", "--watch", "-D", "-d", hcr.TmpDir)
	hcr.cmd.Dir = hcr.TmpDir

	err := hcr.cmd.Start()
	if err != nil {
		return fmt.Errorf("error starting hugo: %v", err)
	}

	return nil
}

func (hcr *HugoCmdRenderer) Stop() error {
	hcr.mtx.Lock()
	defer hcr.mtx.Unlock()

	if hcr.cmd == nil {
		return nil
	}

	err := hcr.cmd.Process.Signal(os.Interrupt)
	if err != nil {
		return err
	}
	err = hcr.cmd.Wait()
	if err != nil {
		return err
	}

	return nil
}