/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package keijumt.todoapp.di

import android.app.Activity
import android.app.Application
import android.os.Bundle
import android.support.v4.app.Fragment
import android.support.v4.app.FragmentActivity
import android.support.v4.app.FragmentManager
import dagger.android.AndroidInjection
import dagger.android.support.AndroidSupportInjection
import dagger.android.support.HasSupportFragmentInjector
import keijumt.todoapp.App

/**
 * Helper class to automatically inject fragments if they implement [Injectable].
 */
object AppAutomaticInjector {

    fun init(app: App) {
        DaggerAppComponent.builder().application(app).build().inject(app)
        app.registerActivityLifecycleCallbacks(object : Application.ActivityLifecycleCallbacks {
            override fun onActivityCreated(activity: Activity, savedInstanceState: Bundle?) {
                handleActivity(activity)
            }

            override fun onActivityStarted(activity: Activity) {

            }

            override fun onActivityResumed(activity: Activity) {

            }

            override fun onActivityPaused(activity: Activity) {

            }

            override fun onActivityStopped(activity: Activity) {

            }

            override fun onActivitySaveInstanceState(activity: Activity, outState: Bundle) {

            }

            override fun onActivityDestroyed(activity: Activity) {

            }
        })
    }

    private fun handleActivity(activity: Activity) {
        if (activity is HasSupportFragmentInjector) {
            AndroidInjection.inject(activity)
        }
        (activity as? FragmentActivity)?.supportFragmentManager?.registerFragmentLifecycleCallbacks(
                object : FragmentManager.FragmentLifecycleCallbacks() {
                    override fun onFragmentCreated(fm: FragmentManager?, f: Fragment?,
                                                   savedInstanceState: Bundle?) {
                        if (f is Injectable) {
                            AndroidSupportInjection.inject(f)
                        }
                    }
                }, true)
    }
}