package jsruntime

import (
	"github.com/dop251/goja"
	"github.com/dop251/goja_nodejs/console"
	"github.com/dop251/goja_nodejs/eventloop"
	"github.com/dop251/goja_nodejs/require"
	"io/ioutil"
	"time"
)

type JsRuntime struct {
	MainSrc       string
	UseSrc        string
	Relys         Relys
	runtime       *goja.Runtime
	registry      *require.Registry
	requireModule *require.RequireModule
}

type Rely struct {
	Variable string
	FileName string
}
type Relys []Rely

func NewJsRuntime(mainFileName string, useFileName string, rels Relys) (*JsRuntime, error) {
	jr := JsRuntime{
		Relys: rels,
	}
	mainScript, err := ioutil.ReadFile(mainFileName)
	if err != nil {
		return nil, err
	}
	jr.MainSrc = string(mainScript)
	jr.registry = new(require.Registry) // this can be shared by multiple runtimes
	loop := eventloop.NewEventLoop()
	loop.Run(func(r *goja.Runtime) {
		jr.runtime = r
	})

	jr.requireModule = jr.registry.Enable(jr.runtime)
	console.Enable(jr.runtime)

	for e := range rels {
		v, err := jr.requireModule.Require(rels[e].FileName)
		if err != nil {
			return nil, err
		}
		jr.runtime.Set(rels[e].Variable, v)
	}

	go func() {
		for {
			useSrc, _ := ioutil.ReadFile(mainFileName)
			jr.UseSrc = string(useSrc)
			time.Sleep(time.Second * 2)
		}
	}()
	return &jr, nil
}

func (jr *JsRuntime) Render(tpl string) string {
	jr.runtime.Set("HTML_SRC", tpl)

	runtime.Set("HTML_OUT", func(data string) {
		context.Writer.WriteHeader(200)
		context.Writer.Write([]byte(data))

		return
	})
}