package io.heckel.ntfy.ui

import android.Manifest
import android.app.AlertDialog
import android.content.ClipData
import android.content.ClipboardManager
import android.content.Context
import android.content.Intent
import android.content.pm.PackageManager
import android.os.Build
import android.os.Bundle
import android.provider.Settings
import android.text.TextUtils
import android.widget.Button
import android.widget.Toast
import androidx.activity.result.contract.ActivityResultContracts
import androidx.annotation.Keep
import androidx.appcompat.app.AppCompatActivity
import androidx.appcompat.app.AppCompatDelegate
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import androidx.fragment.app.DialogFragment
import androidx.lifecycle.lifecycleScope
import androidx.preference.*
import androidx.preference.Preference.OnPreferenceClickListener
import com.google.gson.Gson
import io.heckel.ntfy.BuildConfig
import io.heckel.ntfy.R
import io.heckel.ntfy.backup.Backuper
import io.heckel.ntfy.db.Repository
import io.heckel.ntfy.db.User
import io.heckel.ntfy.service.SubscriberServiceManager
import io.heckel.ntfy.util.*
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import okhttp3.OkHttpClient
import okhttp3.Request
import okhttp3.RequestBody.Companion.toRequestBody
import java.text.SimpleDateFormat
import java.util.*
import java.util.concurrent.TimeUnit

/**
 * Main settings
 *
 * The "nested screen" navigation stuff (for user management) has been taken from
 * https://github.com/googlearchive/android-preferences/blob/master/app/src/main/java/com/example/androidx/preference/sample/MainActivity.kt
 */
class SettingsActivity : AppCompatActivity(), PreferenceFragmentCompat.OnPreferenceStartFragmentCallback,
    UserFragment.UserDialogListener {
    private lateinit var settingsFragment: SettingsFragment
    private lateinit var userSettingsFragment: UserSettingsFragment

    private lateinit var repository: Repository
    private lateinit var serviceManager: SubscriberServiceManager

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_settings)

        Log.d(TAG, "Create $this")

        repository = Repository.getInstance(this)
        serviceManager = SubscriberServiceManager(this)

        if (savedInstanceState == null) {
            settingsFragment = SettingsFragment() // Empty constructor!
            supportFragmentManager
                .beginTransaction()
                .replace(R.id.settings_layout, settingsFragment)
                .commit()
            title = getString(R.string.settings_title)
        } else {
            title = savedInstanceState.getCharSequence(TITLE_TAG)
        }
        supportFragmentManager.addOnBackStackChangedListener {
            if (supportFragmentManager.backStackEntryCount == 0) {
                setTitle(R.string.settings_title)
            }
        }

        // Show 'Back' button
        supportActionBar?.setDisplayHomeAsUpEnabled(true)
    }

    override fun onSaveInstanceState(outState: Bundle) {
        super.onSaveInstanceState(outState)
        // Save current activity title, so we can set it again after a configuration change
        outState.putCharSequence(TITLE_TAG, title)
    }

    override fun onSupportNavigateUp(): Boolean {
        if (supportFragmentManager.popBackStackImmediate()) {
            return true
        }
        return super.onSupportNavigateUp()
    }

    override fun onPreferenceStartFragment(
        caller: PreferenceFragmentCompat,
        pref: Preference
    ): Boolean {
        // Instantiate the new Fragment
        val fragmentClass = pref.fragment ?: return false
        val fragment = supportFragmentManager.fragmentFactory.instantiate(classLoader, fragmentClass)
        fragment.arguments = pref.extras

        // Replace the existing Fragment with the new Fragment
        supportFragmentManager.beginTransaction()
            .replace(R.id.settings_layout, fragment)
            .addToBackStack(null)
            .commit()
        title = pref.title

        // Save user settings fragment for later
        if (fragment is UserSettingsFragment) {
            userSettingsFragment = fragment
        }
        return true
    }

    class SettingsFragment : PreferenceFragmentCompat() {
        private lateinit var repository: Repository
        private lateinit var serviceManager: SubscriberServiceManager
        private var autoDownloadSelection = AUTO_DOWNLOAD_SELECTION_NOT_SET

        override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
            setPreferencesFromResource(R.xml.main_preferences, rootKey)

            // Dependencies (Fragments need a default constructor)
            repository = Repository.getInstance(requireActivity())
            serviceManager = SubscriberServiceManager(requireActivity())
            autoDownloadSelection = repository.getAutoDownloadMaxSize() // Only used for <= Android P, due to permissions request

            // Important note: We do not use the default shared prefs to store settings. Every
            // preferenceDataStore is overridden to use the repository. This is convenient, because
            // everybody has access to the repository.

            // Notifications muted until (global)
            val mutedUntilPrefId = context?.getString(R.string.settings_notifications_muted_until_key) ?: return
            val mutedUntil: ListPreference? = findPreference(mutedUntilPrefId)
            mutedUntil?.value = repository.getGlobalMutedUntil().toString()
            mutedUntil?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val mutedUntilValue = value?.toLongOrNull() ?:return
                    when (mutedUntilValue) {
                        Repository.MUTED_UNTIL_SHOW_ALL -> repository.setGlobalMutedUntil(mutedUntilValue)
                        Repository.MUTED_UNTIL_FOREVER -> repository.setGlobalMutedUntil(mutedUntilValue)
                        Repository.MUTED_UNTIL_TOMORROW -> {
                            val date = Calendar.getInstance()
                            date.add(Calendar.DAY_OF_MONTH, 1)
                            date.set(Calendar.HOUR_OF_DAY, 8)
                            date.set(Calendar.MINUTE, 30)
                            date.set(Calendar.SECOND, 0)
                            date.set(Calendar.MILLISECOND, 0)
                            repository.setGlobalMutedUntil(date.timeInMillis/1000)
                        }
                        else -> {
                            val mutedUntilTimestamp = System.currentTimeMillis()/1000 + mutedUntilValue * 60
                            repository.setGlobalMutedUntil(mutedUntilTimestamp)
                        }
                    }
                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getGlobalMutedUntil().toString()
                }
            }
            mutedUntil?.summaryProvider = Preference.SummaryProvider<ListPreference> {
                when (val mutedUntilValue = repository.getGlobalMutedUntil()) {
                    Repository.MUTED_UNTIL_SHOW_ALL -> getString(R.string.settings_notifications_muted_until_show_all)
                    Repository.MUTED_UNTIL_FOREVER -> getString(R.string.settings_notifications_muted_until_forever)
                    else -> {
                        val formattedDate = formatDateShort(mutedUntilValue)
                        getString(R.string.settings_notifications_muted_until_x, formattedDate)
                    }
                }
            }

            // Minimum priority
            val minPriorityPrefId = context?.getString(R.string.settings_notifications_min_priority_key) ?: return
            val minPriority: ListPreference? = findPreference(minPriorityPrefId)
            minPriority?.value = repository.getMinPriority().toString()
            minPriority?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val minPriorityValue = value?.toIntOrNull() ?:return
                    repository.setMinPriority(minPriorityValue)
                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getMinPriority().toString()
                }
            }
            minPriority?.summaryProvider = Preference.SummaryProvider<ListPreference> { pref ->
                when (val minPriorityValue = pref.value.toIntOrNull() ?: 1) { // 1/low means all priorities
                    PRIORITY_MIN -> getString(R.string.settings_notifications_min_priority_summary_any)
                    PRIORITY_MAX -> getString(R.string.settings_notifications_min_priority_summary_max)
                    else -> {
                        val minPriorityString = toPriorityString(requireContext(), minPriorityValue)
                        getString(R.string.settings_notifications_min_priority_summary_x_or_higher, minPriorityValue, minPriorityString)
                    }
                }
            }

            // Keep alerting for max priority
            val insistentMaxPriorityPrefId = context?.getString(R.string.settings_notifications_insistent_max_priority_key) ?: return
            val insistentMaxPriority: SwitchPreference? = findPreference(insistentMaxPriorityPrefId)
            insistentMaxPriority?.isChecked = repository.getInsistentMaxPriorityEnabled()
            insistentMaxPriority?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putBoolean(key: String?, value: Boolean) {
                    repository.setInsistentMaxPriorityEnabled(value)
                }
                override fun getBoolean(key: String?, defValue: Boolean): Boolean {
                    return repository.getInsistentMaxPriorityEnabled()
                }
            }
            insistentMaxPriority?.summaryProvider = Preference.SummaryProvider<SwitchPreference> { pref ->
                if (pref.isChecked) {
                    getString(R.string.settings_notifications_insistent_max_priority_summary_enabled)
                } else {
                    getString(R.string.settings_notifications_insistent_max_priority_summary_disabled)
                }
            }

            // Channel settings
            val channelPrefsPrefId = context?.getString(R.string.settings_notifications_channel_prefs_key) ?: return
            val channelPrefs: Preference? = findPreference(channelPrefsPrefId)
            channelPrefs?.isVisible = Build.VERSION.SDK_INT >= Build.VERSION_CODES.O
            channelPrefs?.preferenceDataStore = object : PreferenceDataStore() { } // Dummy store to protect from accidentally overwriting
            channelPrefs?.onPreferenceClickListener = OnPreferenceClickListener {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                    startActivity(Intent(Settings.ACTION_APP_NOTIFICATION_SETTINGS).apply {
                        putExtra(Settings.EXTRA_APP_PACKAGE, BuildConfig.APPLICATION_ID)
                    })
                }
                false
            }

            // Auto download
            val autoDownloadPrefId = context?.getString(R.string.settings_notifications_auto_download_key) ?: return
            val autoDownload: ListPreference? = findPreference(autoDownloadPrefId)
            autoDownload?.value = repository.getAutoDownloadMaxSize().toString()
            autoDownload?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val maxSize = value?.toLongOrNull() ?:return
                    repository.setAutoDownloadMaxSize(maxSize)
                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getAutoDownloadMaxSize().toString()
                }
            }
            autoDownload?.summaryProvider = Preference.SummaryProvider<ListPreference> { pref ->
                when (val maxSize = pref.value.toLongOrNull() ?: repository.getAutoDownloadMaxSize()) {
                    Repository.AUTO_DOWNLOAD_NEVER -> getString(R.string.settings_notifications_auto_download_summary_never)
                    Repository.AUTO_DOWNLOAD_ALWAYS -> getString(R.string.settings_notifications_auto_download_summary_always)
                    else -> getString(R.string.settings_notifications_auto_download_summary_smaller_than_x, formatBytes(maxSize, decimals = 0))
                }
            }
            if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.P) {
                autoDownload?.setOnPreferenceChangeListener { _, v ->
                    if (ContextCompat.checkSelfPermission(requireContext(), Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED) {
                        ActivityCompat.requestPermissions(requireActivity(), arrayOf(Manifest.permission.WRITE_EXTERNAL_STORAGE), REQUEST_CODE_WRITE_EXTERNAL_STORAGE_PERMISSION_FOR_AUTO_DOWNLOAD)
                        autoDownloadSelection = v.toString().toLongOrNull() ?: repository.getAutoDownloadMaxSize()
                        false // If permission is granted, auto-download will be enabled in onRequestPermissionsResult()
                    } else {
                        true
                    }
                }
            }

            // Auto delete
            val autoDeletePrefId = context?.getString(R.string.settings_notifications_auto_delete_key) ?: return
            val autoDelete: ListPreference? = findPreference(autoDeletePrefId)
            autoDelete?.value = repository.getAutoDeleteSeconds().toString()
            autoDelete?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val seconds = value?.toLongOrNull() ?:return
                    repository.setAutoDeleteSeconds(seconds)
                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getAutoDeleteSeconds().toString()
                }
            }
            autoDelete?.summaryProvider = Preference.SummaryProvider<ListPreference> { pref ->
                when (pref.value.toLongOrNull() ?: repository.getAutoDeleteSeconds()) {
                    Repository.AUTO_DELETE_NEVER -> getString(R.string.settings_notifications_auto_delete_summary_never)
                    Repository.AUTO_DELETE_ONE_DAY_SECONDS -> getString(R.string.settings_notifications_auto_delete_summary_one_day)
                    Repository.AUTO_DELETE_THREE_DAYS_SECONDS -> getString(R.string.settings_notifications_auto_delete_summary_three_days)
                    Repository.AUTO_DELETE_ONE_WEEK_SECONDS -> getString(R.string.settings_notifications_auto_delete_summary_one_week)
                    Repository.AUTO_DELETE_ONE_MONTH_SECONDS -> getString(R.string.settings_notifications_auto_delete_summary_one_month)
                    Repository.AUTO_DELETE_THREE_MONTHS_SECONDS -> getString(R.string.settings_notifications_auto_delete_summary_three_months)
                    else -> getString(R.string.settings_notifications_auto_delete_summary_one_month) // Must match default const
                }
            }

            // Dark mode
            val darkModePrefId = context?.getString(R.string.settings_general_dark_mode_key) ?: return
            val darkMode: ListPreference? = findPreference(darkModePrefId)
            darkMode?.value = repository.getDarkMode().toString()
            darkMode?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val darkModeValue = value?.toIntOrNull() ?: return
                    repository.setDarkMode(darkModeValue)
                    AppCompatDelegate.setDefaultNightMode(darkModeValue)

                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getDarkMode().toString()
                }
            }
            darkMode?.summaryProvider = Preference.SummaryProvider<ListPreference> { pref ->
                val darkModeValue = pref.value.toIntOrNull() ?: repository.getDarkMode()
                when (darkModeValue) {
                    AppCompatDelegate.MODE_NIGHT_NO -> getString(R.string.settings_general_dark_mode_summary_light)
                    AppCompatDelegate.MODE_NIGHT_YES -> getString(R.string.settings_general_dark_mode_summary_dark)
                    else -> getString(R.string.settings_general_dark_mode_summary_system)
                }
            }

            // Default Base URL
            val appBaseUrl = getString(R.string.app_base_url)
            val defaultBaseUrlPrefId = context?.getString(R.string.settings_general_default_base_url_key) ?: return
            val defaultBaseUrl: EditTextPreference? = findPreference(defaultBaseUrlPrefId)
            defaultBaseUrl?.text = repository.getDefaultBaseUrl() ?: ""
            defaultBaseUrl?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String, value: String?) {
                    val baseUrl = value ?: return
                    repository.setDefaultBaseUrl(baseUrl)
                }
                override fun getString(key: String, defValue: String?): String? {
                    return repository.getDefaultBaseUrl()
                }
            }
            defaultBaseUrl?.setOnBindEditTextListener { editText ->
                editText.addTextChangedListener(AfterChangedTextWatcher {
                    val okayButton: Button = editText.rootView.findViewById(android.R.id.button1)
                    val value = editText.text.toString()
                    okayButton.isEnabled = value.isEmpty() || validUrl(value)
                })
            }
            defaultBaseUrl?.summaryProvider = Preference.SummaryProvider<EditTextPreference> { pref ->
                if (TextUtils.isEmpty(pref.text)) {
                    getString(R.string.settings_general_default_base_url_default_summary, appBaseUrl)
                } else {
                    pref.text
                }
            }

            // Broadcast enabled
            val broadcastEnabledPrefId = context?.getString(R.string.settings_advanced_broadcast_key) ?: return
            val broadcastEnabled: SwitchPreference? = findPreference(broadcastEnabledPrefId)
            broadcastEnabled?.isChecked = repository.getBroadcastEnabled()
            broadcastEnabled?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putBoolean(key: String?, value: Boolean) {
                    repository.setBroadcastEnabled(value)
                }
                override fun getBoolean(key: String?, defValue: Boolean): Boolean {
                    return repository.getBroadcastEnabled()
                }
            }
            broadcastEnabled?.summaryProvider = Preference.SummaryProvider<SwitchPreference> { pref ->
                if (pref.isChecked) {
                    getString(R.string.settings_advanced_broadcast_summary_enabled)
                } else {
                    getString(R.string.settings_advanced_broadcast_summary_disabled)
                }
            }

            // Enable UnifiedPush
            val unifiedPushEnabledPrefId = context?.getString(R.string.settings_advanced_unifiedpush_key) ?: return
            val unifiedPushEnabled: SwitchPreference? = findPreference(unifiedPushEnabledPrefId)
            unifiedPushEnabled?.isChecked = repository.getUnifiedPushEnabled()
            unifiedPushEnabled?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putBoolean(key: String?, value: Boolean) {
                    repository.setUnifiedPushEnabled(value)
                }
                override fun getBoolean(key: String?, defValue: Boolean): Boolean {
                    return repository.getUnifiedPushEnabled()
                }
            }
            unifiedPushEnabled?.summaryProvider = Preference.SummaryProvider<SwitchPreference> { pref ->
                if (pref.isChecked) {
                    getString(R.string.settings_advanced_unifiedpush_summary_enabled)
                } else {
                    getString(R.string.settings_advanced_unifiedpush_summary_disabled)
                }
            }

            // Export logs
            val exportLogsPrefId = context?.getString(R.string.settings_advanced_export_logs_key) ?: return
            val exportLogs: ListPreference? = findPreference(exportLogsPrefId)
            exportLogs?.isVisible = Log.getRecord()
            exportLogs?.preferenceDataStore = object : PreferenceDataStore() { } // Dummy store to protect from accidentally overwriting
            exportLogs?.onPreferenceChangeListener = Preference.OnPreferenceChangeListener { _, v ->
                when (v) {
                    EXPORT_LOGS_COPY_ORIGINAL -> copyLogsToClipboard(scrub = false)
                    EXPORT_LOGS_COPY_SCRUBBED -> copyLogsToClipboard(scrub = true)
                    EXPORT_LOGS_UPLOAD_ORIGINAL -> uploadLogsToNopaste(scrub = false)
                    EXPORT_LOGS_UPLOAD_SCRUBBED -> uploadLogsToNopaste(scrub = true)
                }
                false
            }

            // Clear logs
            val clearLogsPrefId = context?.getString(R.string.settings_advanced_clear_logs_key) ?: return
            val clearLogs: Preference? = findPreference(clearLogsPrefId)
            clearLogs?.isVisible = Log.getRecord()
            clearLogs?.preferenceDataStore = object : PreferenceDataStore() { } // Dummy store to protect from accidentally overwriting
            clearLogs?.onPreferenceClickListener = OnPreferenceClickListener {
                deleteLogs()
                false
            }

            // Record logs
            val recordLogsPrefId = context?.getString(R.string.settings_advanced_record_logs_key) ?: return
            val recordLogsEnabled: SwitchPreference? = findPreference(recordLogsPrefId)
            recordLogsEnabled?.isChecked = Log.getRecord()
            recordLogsEnabled?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putBoolean(key: String?, value: Boolean) {
                    repository.setRecordLogsEnabled(value)
                    Log.setRecord(value)
                    exportLogs?.isVisible = value
                    clearLogs?.isVisible = value
                }
                override fun getBoolean(key: String?, defValue: Boolean): Boolean {
                    return Log.getRecord()
                }
            }
            recordLogsEnabled?.summaryProvider = Preference.SummaryProvider<SwitchPreference> { pref ->
                if (pref.isChecked) {
                    getString(R.string.settings_advanced_record_logs_summary_enabled)
                } else {
                    getString(R.string.settings_advanced_record_logs_summary_disabled)
                }
            }
            recordLogsEnabled?.onPreferenceChangeListener = Preference.OnPreferenceChangeListener { _, _ ->
                lifecycleScope.launch(Dispatchers.IO) {
                    repository.getSubscriptions().forEach { s ->
                        Log.addScrubTerm(shortUrl(s.baseUrl), Log.TermType.Domain)
                        Log.addScrubTerm(s.topic)
                    }
                    repository.getUsers().forEach { u ->
                        Log.addScrubTerm(shortUrl(u.baseUrl), Log.TermType.Domain)
                        Log.addScrubTerm(u.username, Log.TermType.Username)
                        Log.addScrubTerm(u.password, Log.TermType.Password)
                    }
                }
                true
            }

            // Backup
            val backuper = Backuper(requireContext())
            val backupPrefId = context?.getString(R.string.settings_backup_restore_backup_key) ?: return
            val backup: ListPreference? = findPreference(backupPrefId)
            var backupSelection = BACKUP_EVERYTHING
            val backupResultLauncher = registerForActivityResult(ActivityResultContracts.CreateDocument()) { uri ->
                if (uri == null) {
                    return@registerForActivityResult
                }
                lifecycleScope.launch(Dispatchers.IO) {
                    try {
                        when (backupSelection) {
                            BACKUP_EVERYTHING -> backuper.backup(uri)
                            BACKUP_EVERYTHING_NO_USERS -> backuper.backup(uri, withUsers = false)
                            BACKUP_SETTINGS_ONLY -> backuper.backup(uri, withUsers = false, withSubscriptions = false)
                        }
                        requireActivity().runOnUiThread {
                            Toast.makeText(context, getString(R.string.settings_backup_restore_backup_successful), Toast.LENGTH_LONG).show()
                        }
                    } catch (e: Exception) {
                        Log.w(TAG, "Backup failed", e)
                        requireActivity().runOnUiThread {
                            Toast.makeText(context, getString(R.string.settings_backup_restore_backup_failed, e.message), Toast.LENGTH_LONG).show()
                        }
                    }
                }
            }
            backup?.preferenceDataStore = object : PreferenceDataStore() { } // Dummy store to protect from accidentally overwriting
            backup?.onPreferenceChangeListener = Preference.OnPreferenceChangeListener { _, v ->
                backupSelection = v.toString()
                val timestamp = SimpleDateFormat("yyMMdd-HHmm").format(Date())
                val suggestedFilename = when (backupSelection) {
                    BACKUP_EVERYTHING_NO_USERS -> "ntfy-backup-no-users-$timestamp.json"
                    BACKUP_SETTINGS_ONLY -> "ntfy-settings-$timestamp.json"
                    else -> "ntfy-backup-$timestamp.json"
                }
                backupResultLauncher.launch(suggestedFilename)
                false
            }
            backup?.onPreferenceClickListener = OnPreferenceClickListener {
                true
            }

            // Restore
            val restorePrefId = context?.getString(R.string.settings_backup_restore_restore_key) ?: return
            val restore: Preference? = findPreference(restorePrefId)
            val restoreResultLauncher = registerForActivityResult(ActivityResultContracts.GetContent()) { uri ->
                if (uri == null) {
                    return@registerForActivityResult
                }
                lifecycleScope.launch(Dispatchers.IO) {
                    try {
                        val currentDarkMode = repository.getDarkMode()
                        backuper.restore(uri)
                        requireActivity().runOnUiThread {
                            Toast.makeText(context, getString(R.string.settings_backup_restore_restore_successful), Toast.LENGTH_LONG).show()
                            requireActivity().recreate()
                            val newDarkMode = repository.getDarkMode()
                            if (newDarkMode != currentDarkMode) {
                                AppCompatDelegate.setDefaultNightMode(newDarkMode)
                            }
                        }
                    } catch (e: Exception) {
                        Log.w(TAG, "Restore failed", e)
                        requireActivity().runOnUiThread {
                            Toast.makeText(context, getString(R.string.settings_backup_restore_restore_failed, e.message), Toast.LENGTH_LONG).show()
                        }
                    }
                }
            }
            restore?.onPreferenceClickListener = OnPreferenceClickListener {
                // Overly open mime type filter (because of https://github.com/binwiederhier/ntfy/issues/223).
                // This filter could likely be stricter if we'd write the mime type properly in Backuper.backup(),
                // but just in case we want to restore from a file we didn't write outselves, we'll keep this "*/*".
                restoreResultLauncher.launch("*/*")
                true
            }

            // Connection protocol
            val connectionProtocolPrefId = context?.getString(R.string.settings_advanced_connection_protocol_key) ?: return
            val connectionProtocol: ListPreference? = findPreference(connectionProtocolPrefId)
            connectionProtocol?.value = repository.getConnectionProtocol()
            connectionProtocol?.preferenceDataStore = object : PreferenceDataStore() {
                override fun putString(key: String?, value: String?) {
                    val proto = value ?: repository.getConnectionProtocol()
                    repository.setConnectionProtocol(proto)
                    restartService()
                }
                override fun getString(key: String?, defValue: String?): String {
                    return repository.getConnectionProtocol()
                }
            }
            connectionProtocol?.summaryProvider = Preference.SummaryProvider<ListPreference> { pref ->
                when (pref.value) {
                    Repository.CONNECTION_PROTOCOL_WS -> getString(R.string.settings_advanced_connection_protocol_summary_ws)
                    else -> getString(R.string.settings_advanced_connection_protocol_summary_jsonhttp)
                }
            }

            // Version
            val versionPrefId = context?.getString(R.string.settings_about_version_key) ?: return
            val versionPref: Preference? = findPreference(versionPrefId)
            val version = getString(R.string.settings_about_version_format, BuildConfig.VERSION_NAME, BuildConfig.FLAVOR)
            versionPref?.summary = version
            versionPref?.onPreferenceClickListener = OnPreferenceClickListener {
                val context = context ?: return@OnPreferenceClickListener false
                val clipboard = context.getSystemService(Context.CLIPBOARD_SERVICE) as ClipboardManager
                val clip = ClipData.newPlainText("ntfy version", version)
                clipboard.setPrimaryClip(clip)
                Toast
                    .makeText(context, getString(R.string.settings_about_version_copied_to_clipboard_message), Toast.LENGTH_LONG)
                    .show()
                true
            }
        }

        fun setAutoDownload() {
            val autoDownloadSelectionCopy = autoDownloadSelection
            if (autoDownloadSelectionCopy == AUTO_DOWNLOAD_SELECTION_NOT_SET) return
            val autoDownloadPrefId = context?.getString(R.string.settings_notifications_auto_download_key) ?: return
            val autoDownload: ListPreference? = findPreference(autoDownloadPrefId)
            autoDownload?.value = autoDownloadSelectionCopy.toString()
            repository.setAutoDownloadMaxSize(autoDownloadSelectionCopy)
        }

        private fun restartService() {
            serviceManager.restart() // Service will auto-restart
        }

        private fun copyLogsToClipboard(scrub: Boolean) {
            lifecycleScope.launch(Dispatchers.IO) {
                val context = context ?: return@launch
                val log = Log.getFormatted(context, scrub = scrub)
                requireActivity().runOnUiThread {
                    val clipboard = context.getSystemService(Context.CLIPBOARD_SERVICE) as ClipboardManager
                    val clip = ClipData.newPlainText("ntfy logs", log)
                    clipboard.setPrimaryClip(clip)
                    if (scrub) {
                        showScrubDialog(getString(R.string.settings_advanced_export_logs_copied_logs))
                    } else {
                        Toast
                            .makeText(context, getString(R.string.settings_advanced_export_logs_copied_logs), Toast.LENGTH_LONG)
                            .show()
                    }
                }
            }
        }

        private fun uploadLogsToNopaste(scrub: Boolean) {
            lifecycleScope.launch(Dispatchers.IO) {
                Log.d(TAG, "Uploading log to $EXPORT_LOGS_UPLOAD_URL ...")
                val context = context ?: return@launch
                val log = Log.getFormatted(context, scrub = scrub)
                if (log.length > EXPORT_LOGS_UPLOAD_NOTIFY_SIZE_THRESHOLD) {
                    requireActivity().runOnUiThread {
                        Toast
                            .makeText(context, getString(R.string.settings_advanced_export_logs_uploading), Toast.LENGTH_SHORT)
                            .show()
                    }
                }
                val gson = Gson()
                val request = Request.Builder()
                    .url(EXPORT_LOGS_UPLOAD_URL)
                    .put(log.toRequestBody())
                    .build()
                val client = OkHttpClient.Builder()
                    .callTimeout(1, TimeUnit.MINUTES) // Total timeout for entire request
                    .connectTimeout(15, TimeUnit.SECONDS)
                    .readTimeout(15, TimeUnit.SECONDS)
                    .writeTimeout(15, TimeUnit.SECONDS)
                    .build()
                try {
                    client.newCall(request).execute().use { response ->
                        if (!response.isSuccessful) {
                            throw Exception("Unexpected response ${response.code}")
                        }
                        val body = response.body?.string()?.trim()
                        if (body.isNullOrEmpty()) throw Exception("Return body is empty")
                        Log.d(TAG, "Logs uploaded successfully: $body")
                        val resp = gson.fromJson(body.toString(), NopasteResponse::class.java)
                        requireActivity().runOnUiThread {
                            val clipboard = context.getSystemService(Context.CLIPBOARD_SERVICE) as ClipboardManager
                            val clip = ClipData.newPlainText("logs URL", resp.url)
                            clipboard.setPrimaryClip(clip)
                            if (scrub) {
                                showScrubDialog(getString(R.string.settings_advanced_export_logs_copied_url))
                            } else {
                                Toast
                                    .makeText(context, getString(R.string.settings_advanced_export_logs_copied_url), Toast.LENGTH_LONG)
                                    .show()
                            }
                        }
                    }
                } catch (e: Exception) {
                    Log.w(TAG, "Error uploading logs", e)
                    requireActivity().runOnUiThread {
                        Toast
                            .makeText(context, getString(R.string.settings_advanced_export_logs_error_uploading, e.message), Toast.LENGTH_LONG)
                            .show()
                    }
                }
            }
        }

        private fun showScrubDialog(title: String) {
            val scrubbed = Log.getScrubTerms()
            val scrubbedText = if (scrubbed.isNotEmpty()) {
                val scrubTerms = scrubbed.map { e -> "${e.key} -> ${e.value}"}.joinToString(separator = "\n")
                getString(R.string.settings_advanced_export_logs_scrub_dialog_text, scrubTerms)
            } else {
                getString(R.string.settings_advanced_export_logs_scrub_dialog_empty)
            }
            val dialog = AlertDialog.Builder(activity)
                .setTitle(title)
                .setMessage(scrubbedText)
                .setPositiveButton(R.string.settings_advanced_export_logs_scrub_dialog_button_ok) { _, _ -> /* Nothing */ }
                .create()
            dialog.show()
        }

        private fun deleteLogs() {
            lifecycleScope.launch(Dispatchers.IO) {
                Log.deleteAll()
                val context = context ?: return@launch
                requireActivity().runOnUiThread {
                    Toast
                        .makeText(context, getString(R.string.settings_advanced_clear_logs_deleted_toast), Toast.LENGTH_LONG)
                        .show()
                }
            }
        }

        @Keep
        data class NopasteResponse(val url: String)
    }

    class UserSettingsFragment : PreferenceFragmentCompat() {
        private lateinit var repository: Repository

        override fun onCreatePreferences(savedInstanceState: Bundle?, rootKey: String?) {
            setPreferencesFromResource(R.xml.user_preferences, rootKey)
            repository = Repository.getInstance(requireActivity())
            reload()
        }

        data class UserWithMetadata(
            val user: User,
            val topics: List<String>
        )

        fun reload() {
            preferenceScreen.removeAll()
            lifecycleScope.launch(Dispatchers.IO) {
                val baseUrlsWithTopics = repository.getSubscriptions()
                    .groupBy { it.baseUrl }
                    .mapValues { e -> e.value.map { it.topic } }
                val usersByBaseUrl = repository.getUsers()
                    .map { user ->
                        val topics = baseUrlsWithTopics[user.baseUrl] ?: emptyList()
                        UserWithMetadata(user, topics)
                    }
                    .groupBy { it.user.baseUrl }
                activity?.runOnUiThread {
                    addUserPreferences(usersByBaseUrl)
                }
            }
        }

        private fun addUserPreferences(usersByBaseUrl: Map<String, List<UserWithMetadata>>) {
            val baseUrlsInUse = ArrayList(usersByBaseUrl.keys)
            usersByBaseUrl.forEach { entry ->
                val baseUrl = entry.key
                val users = entry.value

                val preferenceCategory = PreferenceCategory(preferenceScreen.context)
                preferenceCategory.title = shortUrl(baseUrl)
                preferenceScreen.addPreference(preferenceCategory)

                users.forEach { user ->
                    val preference = Preference(preferenceScreen.context)
                    preference.title = user.user.username
                    preference.summary = if (user.topics.isEmpty()) {
                        getString(R.string.settings_general_users_prefs_user_not_used)
                    } else if (user.topics.size == 1) {
                        getString(R.string.settings_general_users_prefs_user_used_by_one, user.topics[0])
                    } else {
                        getString(R.string.settings_general_users_prefs_user_used_by_many, user.topics.joinToString(", "))
                    }
                    preference.onPreferenceClickListener = OnPreferenceClickListener { _ ->
                        activity?.let {
                            UserFragment
                                .newInstance(user.user, baseUrlsInUse)
                                .show(it.supportFragmentManager, UserFragment.TAG)
                        }
                        true
                    }
                    preferenceCategory.addPreference(preference)
                }
            }

            // Add user
            val userAddCategory = PreferenceCategory(preferenceScreen.context)
            userAddCategory.title = getString(R.string.settings_general_users_prefs_user_add)
            preferenceScreen.addPreference(userAddCategory)

            val userAddPref = Preference(preferenceScreen.context)
            userAddPref.title = getString(R.string.settings_general_users_prefs_user_add_title)
            userAddPref.summary = getString(R.string.settings_general_users_prefs_user_add_summary)
            userAddPref.onPreferenceClickListener = OnPreferenceClickListener { _ ->
                activity?.let {
                    UserFragment
                        .newInstance(user = null, baseUrlsInUse = baseUrlsInUse)
                        .show(it.supportFragmentManager, UserFragment.TAG)
                }
                true
            }
            userAddCategory.addPreference(userAddPref)
        }
    }

    override fun onRequestPermissionsResult(requestCode: Int, permissions: Array<String>, grantResults: IntArray) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults)
        if (requestCode == REQUEST_CODE_WRITE_EXTERNAL_STORAGE_PERMISSION_FOR_AUTO_DOWNLOAD) {
            if (grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
                setAutoDownload()
            }
        }
    }

    override fun onAddUser(dialog: DialogFragment, user: User) {
        lifecycleScope.launch(Dispatchers.IO) {
            repository.addUser(user) // New users are not used, so no service refresh required
            runOnUiThread {
                userSettingsFragment.reload()
            }
        }
    }

    override fun onUpdateUser(dialog: DialogFragment, user: User) {
        lifecycleScope.launch(Dispatchers.IO) {
            repository.updateUser(user)
            serviceManager.restart() // Editing does not change the user ID
            runOnUiThread {
                userSettingsFragment.reload()
            }
        }
    }

    override fun onDeleteUser(dialog: DialogFragment, baseUrl: String) {
        lifecycleScope.launch(Dispatchers.IO) {
            repository.deleteUser(baseUrl)
            serviceManager.restart()
            runOnUiThread {
                userSettingsFragment.reload()
            }
        }
    }

    private fun setAutoDownload() {
        if (!this::settingsFragment.isInitialized) return
        settingsFragment.setAutoDownload()
    }

    companion object {
        private const val TAG = "NtfySettingsActivity"
        private const val TITLE_TAG = "title"
        private const val REQUEST_CODE_WRITE_EXTERNAL_STORAGE_PERMISSION_FOR_AUTO_DOWNLOAD = 2586
        private const val AUTO_DOWNLOAD_SELECTION_NOT_SET = -99L
        private const val BACKUP_EVERYTHING = "everything"
        private const val BACKUP_EVERYTHING_NO_USERS = "everything_no_users"
        private const val BACKUP_SETTINGS_ONLY = "settings_only"
        private const val EXPORT_LOGS_COPY_ORIGINAL = "copy_original"
        private const val EXPORT_LOGS_COPY_SCRUBBED = "copy_scrubbed"
        private const val EXPORT_LOGS_UPLOAD_ORIGINAL = "upload_original"
        private const val EXPORT_LOGS_UPLOAD_SCRUBBED = "upload_scrubbed"
        private const val EXPORT_LOGS_UPLOAD_URL = "https://nopaste.net/?f=json" // Run by binwiederhier; see https://github.com/binwiederhier/pcopy
        private const val EXPORT_LOGS_UPLOAD_NOTIFY_SIZE_THRESHOLD = 100 * 1024 // Show "Uploading ..." if log larger than X
    }
}