e-ntfy-android/app/src/main/java/io/heckel/ntfy/ui/AddFragment.kt

package io.heckel.ntfy.ui

import android.app.AlertDialog
import android.app.Dialog
import android.content.Context
import android.os.Bundle
import android.text.Editable
import android.text.TextWatcher
import android.util.Log
import android.view.View
import android.widget.Button
import android.widget.CheckBox
import androidx.fragment.app.DialogFragment
import androidx.lifecycle.lifecycleScope
import com.google.android.material.textfield.TextInputEditText
import io.heckel.ntfy.R
import io.heckel.ntfy.data.Database
import io.heckel.ntfy.data.Repository
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch

class AddFragment : DialogFragment() {
    private lateinit var repository: Repository
    private lateinit var subscribeListener: SubscribeListener

    private lateinit var topicNameText: TextInputEditText
    private lateinit var baseUrlText: TextInputEditText
    private lateinit var useAnotherServerCheckbox: CheckBox
    private lateinit var useAnotherServerDescription: View
    private lateinit var instantDeliveryBox: View
    private lateinit var instantDeliveryCheckbox: CheckBox
    private lateinit var instantDeliveryDescription: View
    private lateinit var subscribeButton: Button

    interface SubscribeListener {
        fun onSubscribe(topic: String, baseUrl: String, instant: Boolean)
    }

    override fun onAttach(context: Context) {
        super.onAttach(context)
        subscribeListener = activity as SubscribeListener
    }

    override fun onCreateDialog(savedInstanceState: Bundle?): Dialog {
        if (activity == null) {
            throw IllegalStateException("Activity cannot be null")
        }

        // Dependencies
        val database = Database.getInstance(activity!!.applicationContext)
        repository = Repository.getInstance(database.subscriptionDao(), database.notificationDao())

        // Build root view
        val view = requireActivity().layoutInflater.inflate(R.layout.add_dialog_fragment, null)
        topicNameText = view.findViewById(R.id.add_dialog_topic_text) as TextInputEditText
        baseUrlText = view.findViewById(R.id.add_dialog_base_url_text) as TextInputEditText
        instantDeliveryBox = view.findViewById(R.id.add_dialog_instant_delivery_box)
        instantDeliveryCheckbox = view.findViewById(R.id.add_dialog_instant_delivery_checkbox) as CheckBox
        instantDeliveryDescription = view.findViewById(R.id.add_dialog_instant_delivery_description)
        useAnotherServerCheckbox = view.findViewById(R.id.add_dialog_use_another_server_checkbox) as CheckBox
        useAnotherServerDescription = view.findViewById(R.id.add_dialog_use_another_server_description)

        // Build dialog
        val alert = AlertDialog.Builder(activity)
            .setView(view)
            .setPositiveButton(R.string.add_dialog_button_subscribe) { _, _ ->
                val topic = topicNameText.text.toString()
                val baseUrl = getBaseUrl()
                val instant = if (useAnotherServerCheckbox.isChecked) true else instantDeliveryCheckbox.isChecked
                subscribeListener.onSubscribe(topic, baseUrl, instant)
            }
            .setNegativeButton(R.string.add_dialog_button_cancel) { _, _ ->
                dialog?.cancel()
            }
            .create()

        // Add logic to disable "Subscribe" button on invalid input
        alert.setOnShowListener {
            val dialog = it as AlertDialog

            subscribeButton = dialog.getButton(AlertDialog.BUTTON_POSITIVE)
            subscribeButton.isEnabled = false

            val textWatcher = object : TextWatcher {
                override fun afterTextChanged(s: Editable?) {
                    validateInput()
                }
                override fun onTextChanged(s: CharSequence?, start: Int, before: Int, count: Int) {
                    // Nothing
                }
                override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
                    // Nothing
                }
            }
            topicNameText.addTextChangedListener(textWatcher)
            baseUrlText.addTextChangedListener(textWatcher)
            instantDeliveryCheckbox.setOnCheckedChangeListener { _, isChecked ->
                if (isChecked) instantDeliveryDescription.visibility = View.VISIBLE
                else instantDeliveryDescription.visibility = View.GONE
            }
            useAnotherServerCheckbox.setOnCheckedChangeListener { _, isChecked ->
                if (isChecked) {
                    useAnotherServerDescription.visibility = View.VISIBLE
                    baseUrlText.visibility = View.VISIBLE
                    instantDeliveryBox.visibility = View.GONE
                    instantDeliveryDescription.visibility = View.GONE
                } else {
                    useAnotherServerDescription.visibility = View.GONE
                    baseUrlText.visibility = View.GONE
                    instantDeliveryBox.visibility = View.VISIBLE
                    if (instantDeliveryCheckbox.isChecked) instantDeliveryDescription.visibility = View.VISIBLE
                    else instantDeliveryDescription.visibility = View.GONE
                }
                validateInput()
            }
        }

        return alert
    }

    private fun validateInput() = lifecycleScope.launch(Dispatchers.IO) {
        val baseUrl = getBaseUrl()
        val topic = topicNameText.text.toString()
        val subscription = repository.getSubscription(baseUrl, topic)

        activity?.let {
            it.runOnUiThread {
                if (subscription != null) {
                    subscribeButton.isEnabled = false
                } else if (useAnotherServerCheckbox.isChecked) {
                    subscribeButton.isEnabled = topic.isNotBlank()
                            && "[-_A-Za-z0-9]{1,64}".toRegex().matches(topic)
                            && baseUrl.isNotBlank()
                            && "^https?://.+".toRegex().matches(baseUrl)
                } else {
                    subscribeButton.isEnabled = topic.isNotBlank()
                            && "[-_A-Za-z0-9]{1,64}".toRegex().matches(topic)
                }
            }
        }
    }

    private fun getBaseUrl(): String {
        return if (useAnotherServerCheckbox.isChecked) {
            baseUrlText.text.toString()
        } else {
            getString(R.string.app_base_url)
        }
    }

    companion object {
        const val TAG = "NtfyAffFragment"
    }
}