package module

import (
	"context"
	"sync"

	"forge.cadoles.com/arcad/edge/pkg/app"
	"github.com/dop251/goja"
	"github.com/pkg/errors"
)

func assertContext(v goja.Value, r *goja.Runtime) context.Context {
	if c, ok := v.Export().(context.Context); ok {
		return c
	}

	panic(r.NewTypeError("value should be a context"))
}

type ContextModule struct {
	ctx   BackendContext
	mutex sync.RWMutex
}

func (m *ContextModule) Name() string {
	return "context"
}

func (m *ContextModule) get(call goja.FunctionCall, rt *goja.Runtime) goja.Value {
	m.mutex.RLock()
	defer m.mutex.RUnlock()

	return rt.ToValue(m.ctx)
}

func (m *ContextModule) Export(export *goja.Object) {
	if err := export.Set("get", m.get); err != nil {
		panic(errors.Wrap(err, "could not set 'get' function"))
	}
}

func ContextModuleFactory() app.BackendModuleFactory {
	return func(backend *app.Backend) app.BackendModule {
		return &ContextModule{
			ctx: BackendContext{
				Context: context.Background(),
			},
			mutex: sync.RWMutex{},
		}
	}
}

type BackendContext struct {
	context.Context
}