package xyz.adjutor.aniki.topmanga

import android.content.Context
import android.content.SharedPreferences
import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Button
import androidx.fragment.app.Fragment
import androidx.navigation.fragment.findNavController
import androidx.recyclerview.widget.LinearLayoutManager
import androidx.recyclerview.widget.RecyclerView
import androidx.swiperefreshlayout.widget.SwipeRefreshLayout
import com.google.android.material.snackbar.Snackbar
import com.google.gson.GsonBuilder
import com.google.gson.reflect.TypeToken
import retrofit2.Call
import retrofit2.Callback
import retrofit2.Response
import retrofit2.Retrofit
import retrofit2.converter.gson.GsonConverterFactory
import xyz.adjutor.aniki.R
import java.lang.reflect.Type

class TopMangaPage : Fragment() {

    var sharedPreferences: SharedPreferences? = null
    val gson = GsonBuilder()
            .setLenient()
            .create()
    var base_url = "https://api.jikan.moe/" //the api's base url

    override fun onCreateView(
            inflater: LayoutInflater, container: ViewGroup?,
            savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        val view = inflater.inflate(R.layout.top_manga_page, container, false)

        sharedPreferences = view.context.getSharedPreferences("sp_manga", Context.MODE_PRIVATE)

        val mangaList: List<TopManga>? = getDataFromCache()
        if(mangaList != null ){
            showList(view, mangaList)
        } else {
            makeApiCall(view, base_url)
        }

        return view
    }

    private fun getDataFromCache(): List<TopManga>? {
        //the value of the mangaList json, if nothing is found, return null
        val jsonManga: String? = sharedPreferences?.getString("jsonMangaList", null)

        //if it's null, well, return null
        if(jsonManga == null) {
            return null
        } else { //else deserialize the list and return it
            val listType: Type = object : TypeToken<List<TopManga>>() {}.type
            return gson.fromJson(jsonManga, listType)
        }
    }

    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)

        //button to return to the home page
        view.findViewById<Button>(R.id.button_home).setOnClickListener {
            findNavController().navigate(R.id.action_TopMangaPage_to_HomePage)
        }

        fun updateList() {
            makeApiCall(view,base_url)
            Snackbar.make(requireView(), "Data refreshed", Snackbar.LENGTH_LONG)
                .setAction("Action", null).show()
        }
        val swipeRefresh: SwipeRefreshLayout = view.findViewById(R.id.swiperefresh)
        swipeRefresh.setOnRefreshListener{
            updateList()
            swipeRefresh.isRefreshing = false
        }

    }

    //display the recyclerview
    fun showList(view: View, mangaList: List<TopManga> ){
        val recyclerView: RecyclerView = view.findViewById(R.id.recycler_view)
        recyclerView.setHasFixedSize(true)
        recyclerView.layoutManager = LinearLayoutManager(view.context)
        recyclerView.adapter = TopMangaAdapter(mangaList)
    }

    private fun makeApiCall(view: View, BASE_URL: String) {

        val retrofit = Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create(gson))
                .build()

        val service = retrofit.create(TopMangaApi::class.java)
        val call = service.getTopMangaData()

        call.enqueue(object : Callback<RestTopMangaResponse> {
            override fun onResponse(call: Call<RestTopMangaResponse>, response: Response<RestTopMangaResponse>) {
                if(response.isSuccessful && response.body() != null){ //if the code returned is >= 200 and < 300 AND the the body ain't empty

                    val mangaList: List<TopManga> = response.body()!!.getResults() //getting the "top" field containing our list of TopMangas
                    saveList(mangaList)
                    showList(view, mangaList) //calling the method in charge of displaying on the recyclerview

                } else {
                    showError() //a snackbar
                }
            }

            override fun onFailure(call: Call<RestTopMangaResponse>, t: Throwable) {
                showError()
            }

        })
    }

    private fun saveList(mangaList: List<TopManga>) {
        val jsonString: String = gson.toJson(mangaList)

        sharedPreferences
                ?.edit()
                ?.putString("jsonMangaList", jsonString)
                ?.apply()
    }

    private fun showError() {
        Snackbar.make(requireView(), "API ERROR", Snackbar.LENGTH_LONG)
                .setAction("Action", null).show()
    }

}