package com.schoolapp.cleverclass

import android.content.Context
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.Image
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxHeight
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.foundation.text.KeyboardOptions
import androidx.compose.foundation.text.selection.TextSelectionColors
import androidx.compose.foundation.verticalScroll
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.filled.ArrowBack
import androidx.compose.material.icons.outlined.Delete
import androidx.compose.material.icons.outlined.Info
import androidx.compose.material3.AlertDialog
import androidx.compose.material3.ExperimentalMaterial3Api
import androidx.compose.material3.Icon
import androidx.compose.material3.IconButton
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.OutlinedTextField
import androidx.compose.material3.Surface
import androidx.compose.material3.Text
import androidx.compose.material3.TextFieldDefaults
import androidx.compose.material3.TopAppBar
import androidx.compose.material3.TopAppBarDefaults
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.res.painterResource
import androidx.compose.ui.text.input.KeyboardType
import androidx.compose.ui.text.input.PasswordVisualTransformation
import androidx.compose.ui.text.input.VisualTransformation
import androidx.compose.ui.unit.dp
import com.schoolapp.cleverclass.ui.theme.CleverClassTheme
import com.schoolapp.cleverclass.ui.theme.InputPrimaryColor
import com.schoolapp.cleverclass.ui.theme.InputSecondaryColor

private lateinit var activityType : String

class DSBLoginActivity : ComponentActivity() {
    companion object{
        const val TYPE_KEY = "type_key"
    }
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        activityType = intent.getStringExtra(TYPE_KEY).toString()

        setContent {
            CleverClassTheme {
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    DSBLoginContent(activity = this)
                }
            }
        }
    }
}


// Content of DSBLogin
@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun DSBLoginContent(activity: ComponentActivity){
    val inputFieldColors = TextFieldDefaults.outlinedTextFieldColors(
        textColor = MaterialTheme.colorScheme.onPrimaryContainer,
        containerColor = MaterialTheme.colorScheme.secondaryContainer,
        cursorColor = InputPrimaryColor,
        selectionColors = TextSelectionColors(
            handleColor = InputPrimaryColor,
            backgroundColor = InputSecondaryColor
        ),
        focusedBorderColor = InputSecondaryColor,
        unfocusedBorderColor = Color.Transparent
    )

    val sharedPreferences = activity.getSharedPreferences("DSBmobile", Context.MODE_PRIVATE)
    val editor = sharedPreferences.edit()

    var username by remember {
        mutableStateOf(sharedPreferences.getString("username", "").toString())
    }
    var password by remember {
        mutableStateOf(sharedPreferences.getString("password", "").toString())
    }
    var showPassword by remember {
        mutableStateOf(false)
    }

    var showInfo by remember {
        mutableStateOf(false)
    }
    var showDeleteConfirmation by remember {
        mutableStateOf(false)
    }

    Column {
        TopAppBar(
            colors = TopAppBarDefaults.centerAlignedTopAppBarColors(MaterialTheme.colorScheme.primaryContainer),
            title = { Text(text = "") },
            navigationIcon = {
                IconButton(onClick = { activity.finish() }) {
                    Icon(
                        imageVector = Icons.Filled.ArrowBack,
                        contentDescription = null,
                        modifier = Modifier.size(28.dp),
                        tint = MaterialTheme.colorScheme.onPrimaryContainer
                    )
                }
            },
            modifier = Modifier.fillMaxWidth()
        )

        Column(
            verticalArrangement = Arrangement.Center,
            modifier = Modifier
                .fillMaxHeight()
                .verticalScroll(rememberScrollState())
        ) {
            Surface(
                color = MaterialTheme.colorScheme.primaryContainer,
                shape = RoundedCornerShape(20),
                modifier = Modifier.padding(16.dp)
            ) {
                Column(horizontalAlignment = Alignment.CenterHorizontally,
                    modifier = Modifier.padding(16.dp)
                ) {
                    Row(verticalAlignment = Alignment.CenterVertically) {
                        Text(
                            text = "DSBmobile Login Daten",
                            style = MaterialTheme.typography.labelMedium,
                            color = MaterialTheme.colorScheme.onPrimaryContainer,
                            modifier = Modifier.padding(10.dp)
                        )
                        
                        Spacer(modifier = Modifier.weight(1f))
                        
                        if (activityType == "Settings")
                            IconButton(onClick = { showDeleteConfirmation = !showDeleteConfirmation }) {
                                Icon(
                                    imageVector = Icons.Outlined.Delete,
                                    contentDescription = null,
                                    modifier = Modifier.size(28.dp),
                                    tint = MaterialTheme.colorScheme.onPrimaryContainer
                                )
                            }
                        else if (activityType == "FirstTime")
                            IconButton(onClick = { showInfo = !showInfo }) {
                                Icon(
                                    imageVector = Icons.Outlined.Info,
                                    contentDescription = null,
                                    tint = MaterialTheme.colorScheme.onPrimaryContainer
                                )
                            }
                    }
                    
                    Spacer(modifier = Modifier.height(16.dp))

                    OutlinedTextField(
                        value = username,
                        onValueChange = { username = it },
                        placeholder = {
                            Text(
                                text = "Benutzername",
                                style = MaterialTheme.typography.labelMedium,
                                color = MaterialTheme.colorScheme.primaryContainer
                            )
                        },
                        modifier = Modifier.fillMaxWidth(),
                        singleLine = true,
                        shape = RoundedCornerShape(20),
                        textStyle = MaterialTheme.typography.labelMedium,
                        colors = inputFieldColors
                    )

                    Spacer(modifier = Modifier.height(16.dp))

                    OutlinedTextField(
                        value = password,
                        onValueChange = { password = it },
                        placeholder = {
                            Text(
                                text = "Passwort",
                                style = MaterialTheme.typography.labelMedium,
                                color = MaterialTheme.colorScheme.primaryContainer
                            )
                        },
                        modifier = Modifier.fillMaxWidth(),
                        singleLine = true,
                        shape = RoundedCornerShape(20),
                        textStyle = MaterialTheme.typography.labelMedium,
                        colors = inputFieldColors,
                        visualTransformation = if(showPassword) VisualTransformation.None else PasswordVisualTransformation(),
                        keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
                        trailingIcon = {
                            IconButton(onClick = { showPassword = !showPassword })
                            {
                                Image(
                                    painter = painterResource(
                                        id = if(showPassword)
                                            R.drawable.baseline_visibility_24
                                        else
                                            R.drawable.baseline_visibility_off_24
                                    ),
                                    contentDescription = null,
                                )
                            }
                        }
                    )

                    Spacer(modifier = Modifier.height(10.dp))

                    Box(
                        contentAlignment = Alignment.Center,
                        modifier = Modifier.clickable {
                            editor.putString("username", username)
                            editor.putString("password", password)
                            editor.apply()
                            activity.finish()
                        }
                    ) {
                        Text(
                            text = "Speichern",
                            color = MaterialTheme.colorScheme.secondary,
                            style = MaterialTheme.typography.labelMedium,
                            modifier = Modifier.padding(10.dp)
                        )
                    }
                }
            }
        }
    }

    if (showInfo) {
        AlertDialog(
            onDismissRequest = { showInfo = false },
            text = {
                Text(
                    text = "Der Benutzername und das Passwort können später in den Einstellungen geändert werden",
                    color = MaterialTheme.colorScheme.onPrimaryContainer,
                    style = MaterialTheme.typography.labelMedium)
            },
            confirmButton = {
                Text(
                    text = "Schließen",
                    color = MaterialTheme.colorScheme.secondary,
                    style = MaterialTheme.typography.labelMedium,
                    modifier = Modifier.clickable { showInfo = false }
                )
            },
            containerColor = MaterialTheme.colorScheme.primaryContainer,
            modifier = Modifier
                .padding(5.dp)
        )
    }

    if (showDeleteConfirmation) {
        AlertDialog(
            onDismissRequest = { showDeleteConfirmation = false },
            text = {
                Text(
                    text = "Möchten Sie wirklich die Anmeldedaten löschen?",
                    color = MaterialTheme.colorScheme.onPrimaryContainer,
                    style = MaterialTheme.typography.labelMedium
                )
            },
            confirmButton = {
                Row(modifier = Modifier.fillMaxWidth()){
                    Text(
                        text = "Bestätigen",
                        color = MaterialTheme.colorScheme.secondary,
                        style = MaterialTheme.typography.labelMedium,
                        modifier = Modifier.clickable {
                            editor.putString("username", "")
                            editor.putString("password", "")
                            editor.apply()
                            showDeleteConfirmation = false
                            activity.finish()
                        }
                    )

                    Spacer(modifier = Modifier.weight(1f))

                    Text(
                        text = "Abbrechen",
                        color = MaterialTheme.colorScheme.secondary,
                        style = MaterialTheme.typography.labelMedium,
                        modifier = Modifier.clickable { showDeleteConfirmation = false }
                    )
                }
            },
            containerColor = MaterialTheme.colorScheme.primaryContainer
        )
    }
}