/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.fenix.loginexceptions

import android.os.Bundle
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import androidx.fragment.app.Fragment
import androidx.lifecycle.Observer
import androidx.lifecycle.asLiveData
import androidx.lifecycle.lifecycleScope
import kotlinx.android.synthetic.main.fragment_exceptions.view.*
import kotlinx.coroutines.Dispatchers.IO
import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.launch
import mozilla.components.feature.logins.exceptions.LoginException
import mozilla.components.lib.state.ext.consumeFrom
import org.mozilla.fenix.R
import org.mozilla.fenix.components.StoreProvider
import org.mozilla.fenix.ext.requireComponents
import org.mozilla.fenix.ext.showToolbar

/**
 * Displays a list of sites that are exempted from saving logins,
 * along with controls to remove the exception.
 */
class LoginExceptionsFragment : Fragment() {
    private lateinit var exceptionsStore: ExceptionsFragmentStore
    private lateinit var exceptionsView: LoginExceptionsView
    private lateinit var exceptionsInteractor: LoginExceptionsInteractor

    override fun onResume() {
        super.onResume()
        showToolbar(getString(R.string.preference_exceptions))
    }

    override fun onCreateView(
        inflater: LayoutInflater,
        container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        val view = inflater.inflate(R.layout.fragment_exceptions, container, false)
        exceptionsStore = StoreProvider.get(this) {
            ExceptionsFragmentStore(
                ExceptionsFragmentState(
                    items = listOf()
                )
            )
        }
        exceptionsInteractor =
            LoginExceptionsInteractor(::deleteOneItem, ::deleteAllItems)
        exceptionsView = LoginExceptionsView(view.exceptionsLayout, exceptionsInteractor)
        subscribeToLoginExceptions()
        return view
    }

    private fun subscribeToLoginExceptions(): Observer<List<LoginException>> {
        return Observer<List<LoginException>> { exceptions ->
            exceptionsStore.dispatch(ExceptionsFragmentAction.Change(exceptions))
        }.also { observer ->
            requireComponents.core.loginExceptionStorage.getLoginExceptions().asLiveData()
                .observe(viewLifecycleOwner, observer)
        }
    }

    @ExperimentalCoroutinesApi
    override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
        super.onViewCreated(view, savedInstanceState)
        consumeFrom(exceptionsStore) {
            exceptionsView.update(it)
        }
    }

    private fun deleteAllItems() {
        viewLifecycleOwner.lifecycleScope.launch(IO) {
            requireComponents.core.loginExceptionStorage.deleteAllLoginExceptions()
        }
    }

    private fun deleteOneItem(item: LoginException) {
        viewLifecycleOwner.lifecycleScope.launch(IO) {
            requireComponents.core.loginExceptionStorage.removeLoginException(item)
        }
    }
}