/*
 * Copyright © 2019 WireGuard LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */
package com.wireguard.android.preference

import android.annotation.SuppressLint
import android.content.Context
import android.content.Intent
import android.system.OsConstants
import android.util.AttributeSet
import android.widget.Toast
import androidx.preference.Preference
import com.wireguard.android.Application
import com.wireguard.android.R
import com.wireguard.android.activity.SettingsActivity
import com.wireguard.android.util.ErrorMessages
import com.wireguard.android.util.lifecycleScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import kotlinx.coroutines.withContext
import kotlin.system.exitProcess

class ModuleDownloaderPreference(context: Context, attrs: AttributeSet?) : Preference(context, attrs) {
    private var state = State.INITIAL
    override fun getSummary() = context.getString(state.messageResourceId)

    override fun getTitle() = context.getString(R.string.module_installer_title)

    @SuppressLint("ApplySharedPref")
    override fun onClick() {
        setState(State.WORKING)
        lifecycleScope.launch(Dispatchers.Main.immediate) {
            try {
                when (withContext(Dispatchers.IO) { Application.getModuleLoader().download() }) {
                    OsConstants.ENOENT -> setState(State.NOTFOUND)
                    OsConstants.EXIT_SUCCESS -> {
                        setState(State.SUCCESS)
                        Application.getSharedPreferences().edit().remove("disable_kernel_module").commit()
                        withContext(Dispatchers.IO) {
                            val restartIntent = Intent(context, SettingsActivity::class.java)
                            restartIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)
                            restartIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                            Application.get().startActivity(restartIntent)
                            exitProcess(0)
                        }
                    }
                    else -> setState(State.FAILURE)
                }
            } catch (e: Throwable) {
                setState(State.FAILURE)
                Toast.makeText(context, ErrorMessages[e], Toast.LENGTH_LONG).show()
            }
        }
    }

    private fun setState(state: State) {
        if (this.state == state) return
        this.state = state
        if (isEnabled != state.shouldEnableView) isEnabled = state.shouldEnableView
        notifyChanged()
    }

    private enum class State(val messageResourceId: Int, val shouldEnableView: Boolean) {
        INITIAL(R.string.module_installer_initial, true),
        FAILURE(R.string.module_installer_error, true),
        WORKING(R.string.module_installer_working, false),
        SUCCESS(R.string.success_application_will_restart, false),
        NOTFOUND(R.string.module_installer_not_found, false);
    }
}