package com.notifyhub.viewer.ui

import android.Manifest
import android.content.Context
import android.content.Intent
import android.content.pm.PackageManager
import android.os.Build
import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.core.app.ActivityCompat
import androidx.core.content.ContextCompat
import androidx.fragment.app.Fragment
import androidx.lifecycle.lifecycleScope
import androidx.viewpager2.adapter.FragmentStateAdapter
import androidx.viewpager2.widget.ViewPager2
import com.google.android.material.tabs.TabLayout
import com.google.android.material.tabs.TabLayoutMediator
import com.google.firebase.messaging.FirebaseMessaging
import com.notifyhub.viewer.NotizViewerApp
import com.notifyhub.viewer.R
import com.notifyhub.viewer.data.AuthRepository
import com.notifyhub.viewer.databinding.ActivityHomeBinding
import com.notifyhub.viewer.push.NotizMessagingService
import com.notifyhub.viewer.util.deviceName
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import kotlinx.coroutines.withContext

class HomeActivity : AppCompatActivity() {
    private lateinit var binding: ActivityHomeBinding
    private lateinit var app: NotizViewerApp

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        app = application as NotizViewerApp
        if (!app.preferences.isLoggedIn()) {
            startActivity(Intent(this, LoginActivity::class.java))
            finish()
            return
        }

        binding = ActivityHomeBinding.inflate(layoutInflater)
        setContentView(binding.root)

        val pages = buildPageList()
        val pagerAdapter = object : FragmentStateAdapter(this) {
            override fun getItemCount(): Int = pages.size
            override fun createFragment(position: Int): Fragment = pages[position].fragment
        }
        binding.viewPager.adapter = pagerAdapter

        TabLayoutMediator(binding.tabLayout, binding.viewPager) { tab, position ->
            tab.text = getString(pages[position].titleRes)
        }.attach()

        NotizMessagingService.ensureChannel(this)
        requestNotificationPermission()
        registerPushToken()

        binding.viewPager.registerOnPageChangeCallback(object : ViewPager2.OnPageChangeCallback() {
            override fun onPageSelected(position: Int) {
                (pages[position].fragment as? Refreshable)?.refresh()
            }
        })
    }

    private fun buildPageList(): List<PageItem> {
        val items = mutableListOf<PageItem>()
        items.add(PageItem(R.string.tab_home, HomeFragment()))
        if (app.preferences.hasPage("messages")) {
            items.add(PageItem(R.string.tab_messages, MessagesFragment()))
        }
        if (app.preferences.hasPage("alerts")) {
            items.add(PageItem(R.string.tab_alerts, AlertsFragment()))
        }
        items.add(PageItem(R.string.tab_account, AccountFragment()))
        return items
    }

    private fun requestNotificationPermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU &&
            ContextCompat.checkSelfPermission(this, Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED
        ) {
            ActivityCompat.requestPermissions(this, arrayOf(Manifest.permission.POST_NOTIFICATIONS), 100)
        }
    }

    private fun registerPushToken() {
        lifecycleScope.launch {
            try {
                val token = withContext(Dispatchers.IO) { FirebaseMessaging.getInstance().token.result }
                val repo = AuthRepository(app.api, app.preferences, deviceName())
                withContext(Dispatchers.IO) { repo.registerPushToken(token) }
            } catch (_: Exception) {
                // Firebase not configured (no google-services.json). Push silently disabled.
            }
        }
    }

    private data class PageItem(val titleRes: Int, val fragment: Fragment)

    interface Refreshable {
        fun refresh()
    }

    companion object {
        fun deepLinkIntent(context: Context, type: String, alertId: Int?, messageId: Int?): Intent {
            val intent = Intent(context, HomeActivity::class.java)
            intent.flags = Intent.FLAG_ACTIVITY_SINGLE_TOP or Intent.FLAG_ACTIVITY_CLEAR_TOP
            intent.putExtra(EXTRA_PUSH_TYPE, type)
            alertId?.let { intent.putExtra(EXTRA_ALERT_ID, it) }
            messageId?.let { intent.putExtra(EXTRA_MESSAGE_ID, it) }
            return intent
        }

        const val EXTRA_PUSH_TYPE = "extra_push_type"
        const val EXTRA_ALERT_ID = "extra_alert_id"
        const val EXTRA_MESSAGE_ID = "extra_message_id"
    }
}