add payment ledger impl and payu impl

app/build.gradle.kts

@@ -35,6 +35,7 @@ android {
     }
     buildFeatures {
         compose = true
+        buildConfig = true
     }
 }
 
@@ -60,6 +61,7 @@ dependencies {
     implementation(libs.lottie.compose)
     implementation(libs.calendar.compose)
     implementation(libs.libphonenumber)
+    implementation(libs.zxing.core)
     implementation(platform(libs.firebase.bom))
     implementation(libs.firebase.auth.ktx)
     implementation(libs.kotlinx.coroutines.play.services)

app/src/main/java/com/android/trisolarispms/MainActivity.kt

@@ -25,6 +25,7 @@ import com.android.trisolarispms.ui.roomstay.ManageRoomStaySelection
 import com.android.trisolarispms.ui.roomstay.BookingRoomStaysScreen
 import com.android.trisolarispms.ui.roomstay.BookingDetailsTabsScreen
 import com.android.trisolarispms.ui.home.HomeScreen
+import com.android.trisolarispms.ui.payment.BookingPaymentsScreen
 import com.android.trisolarispms.ui.property.AddPropertyScreen
 import com.android.trisolarispms.ui.room.RoomFormScreen
 import com.android.trisolarispms.ui.room.RoomsScreen
@@ -35,6 +36,8 @@ import com.android.trisolarispms.ui.roomimage.ImageTagsScreen
 import com.android.trisolarispms.ui.roomimage.AddImageTagScreen
 import com.android.trisolarispms.ui.roomimage.EditImageTagScreen
 import com.android.trisolarispms.ui.roomstay.ActiveRoomStaysScreen
+import com.android.trisolarispms.ui.payu.PayuSettingsScreen
+import com.android.trisolarispms.ui.payu.PayuQrScreen
 import com.android.trisolarispms.ui.roomtype.AddAmenityScreen
 import com.android.trisolarispms.ui.roomtype.AddRoomTypeScreen
 import com.android.trisolarispms.ui.roomtype.AmenitiesScreen
@@ -83,6 +86,11 @@ class MainActivity : ComponentActivity() {
                             it == "ADMIN" || it == "MANAGER" || it == "STAFF"
                         } == true
                     }
+                    val canManagePayuSettings: (String) -> Boolean = { propertyId ->
+                        state.isSuperAdmin || state.propertyRoles[propertyId]?.any {
+                            it == "ADMIN" || it == "MANAGER"
+                        } == true
+                    }
 
                     BackHandler(enabled = currentRoute != AppRoute.Home) {
                         when (currentRoute) {
@@ -114,6 +122,15 @@ class MainActivity : ComponentActivity() {
                                 currentRoute.propertyId,
                                 currentRoute.roomTypeId
                             )
+                            is AppRoute.PayuSettings -> route.value = AppRoute.ActiveRoomStays(
+                                currentRoute.propertyId,
+                                selectedPropertyName.value ?: "Property"
+                            )
+                            is AppRoute.PayuQr -> route.value = AppRoute.BookingDetailsTabs(
+                                currentRoute.propertyId,
+                                currentRoute.bookingId,
+                                null
+                            )
                             is AppRoute.CreateBooking -> route.value = AppRoute.ActiveRoomStays(
                                 currentRoute.propertyId,
                                 selectedPropertyName.value ?: "Property"
@@ -157,6 +174,11 @@ class MainActivity : ComponentActivity() {
                                 currentRoute.propertyId,
                                 selectedPropertyName.value ?: "Property"
                             )
+                            is AppRoute.BookingPayments -> route.value = AppRoute.BookingDetailsTabs(
+                                currentRoute.propertyId,
+                                currentRoute.bookingId,
+                                null
+                            )
                         }
                     }
 
@@ -253,6 +275,8 @@ class MainActivity : ComponentActivity() {
                             onBack = { route.value = AppRoute.Home },
                             onViewRooms = { route.value = AppRoute.Rooms(currentRoute.propertyId) },
                             onCreateBooking = { route.value = AppRoute.CreateBooking(currentRoute.propertyId) },
+                            showPayuSettings = canManagePayuSettings(currentRoute.propertyId),
+                            onPayuSettings = { route.value = AppRoute.PayuSettings(currentRoute.propertyId) },
                             onManageRoomStay = { booking ->
                                 val fromAt = booking.checkInAt?.takeIf { it.isNotBlank() }
                                     ?: booking.expectedCheckInAt.orEmpty()
@@ -281,6 +305,28 @@ class MainActivity : ComponentActivity() {
                                 )
                             }
                         )
+                        is AppRoute.PayuSettings -> PayuSettingsScreen(
+                            propertyId = currentRoute.propertyId,
+                            onBack = {
+                                route.value = AppRoute.ActiveRoomStays(
+                                    currentRoute.propertyId,
+                                    selectedPropertyName.value ?: "Property"
+                                )
+                            }
+                        )
+                        is AppRoute.PayuQr -> PayuQrScreen(
+                            propertyId = currentRoute.propertyId,
+                            bookingId = currentRoute.bookingId,
+                            pendingAmount = currentRoute.pendingAmount,
+                            guestPhone = currentRoute.guestPhone,
+                            onBack = {
+                                route.value = AppRoute.BookingDetailsTabs(
+                                    currentRoute.propertyId,
+                                    currentRoute.bookingId,
+                                    null
+                                )
+                            }
+                        )
                         is AppRoute.ManageRoomStaySelect -> ManageRoomStaySelectScreen(
                             propertyId = currentRoute.propertyId,
                             bookingFromAt = currentRoute.fromAt,
@@ -420,6 +466,32 @@ class MainActivity : ComponentActivity() {
                                     currentRoute.bookingId,
                                     guestId
                                 )
+                            },
+                            onOpenPayuQr = { pendingAmount, guestPhone ->
+                                route.value = AppRoute.PayuQr(
+                                    propertyId = currentRoute.propertyId,
+                                    bookingId = currentRoute.bookingId,
+                                    pendingAmount = pendingAmount,
+                                    guestPhone = guestPhone
+                                )
+                            },
+                            onOpenPayments = {
+                                route.value = AppRoute.BookingPayments(
+                                    propertyId = currentRoute.propertyId,
+                                    bookingId = currentRoute.bookingId
+                                )
+                            }
+                        )
+                        is AppRoute.BookingPayments -> BookingPaymentsScreen(
+                            propertyId = currentRoute.propertyId,
+                            bookingId = currentRoute.bookingId,
+                            canAddCash = canManagePayuSettings(currentRoute.propertyId),
+                            onBack = {
+                                route.value = AppRoute.BookingDetailsTabs(
+                                    currentRoute.propertyId,
+                                    currentRoute.bookingId,
+                                    null
+                                )
                             }
                         )
                         is AppRoute.Rooms -> RoomsScreen(

app/src/main/java/com/android/trisolarispms/data/api/ApiService.kt

@@ -15,4 +15,6 @@ interface ApiService :
     TransportApi,
     InboundEmailApi,
     AmenityApi,
-    RatePlanApi
+    RatePlanApi,
+    PayuSettingsApi,
+    PayuPaymentLinkSettingsApi

app/src/main/java/com/android/trisolarispms/data/api/BookingApi.kt

@@ -14,6 +14,12 @@ import com.android.trisolarispms.data.api.model.BookingBulkCheckInRequest
 import com.android.trisolarispms.data.api.model.BookingExpectedDatesRequest
 import com.android.trisolarispms.data.api.model.BookingDetailsResponse
 import com.android.trisolarispms.data.api.model.RoomStayDto
+import com.android.trisolarispms.data.api.model.PayuQrRequest
+import com.android.trisolarispms.data.api.model.PayuQrResponse
+import com.android.trisolarispms.data.api.model.PayuLinkRequest
+import com.android.trisolarispms.data.api.model.PayuLinkResponse
+import com.android.trisolarispms.data.api.model.PaymentDto
+import com.android.trisolarispms.data.api.model.PaymentCreateRequest
 import retrofit2.Response
 import retrofit2.http.Body
 import retrofit2.http.GET
@@ -95,4 +101,31 @@ interface BookingApi {
         @Path("bookingId") bookingId: String,
         @Body body: BookingRoomStayCreateRequest
     ): Response<RoomStayDto>
+
+    @POST("properties/{propertyId}/bookings/{bookingId}/payments/payu/qr")
+    suspend fun generatePayuQr(
+        @Path("propertyId") propertyId: String,
+        @Path("bookingId") bookingId: String,
+        @Body body: PayuQrRequest
+    ): Response<PayuQrResponse>
+
+    @POST("properties/{propertyId}/bookings/{bookingId}/payments/payu/link")
+    suspend fun generatePayuLink(
+        @Path("propertyId") propertyId: String,
+        @Path("bookingId") bookingId: String,
+        @Body body: PayuLinkRequest
+    ): Response<PayuLinkResponse>
+
+    @GET("properties/{propertyId}/bookings/{bookingId}/payments")
+    suspend fun listPayments(
+        @Path("propertyId") propertyId: String,
+        @Path("bookingId") bookingId: String
+    ): Response<List<PaymentDto>>
+
+    @POST("properties/{propertyId}/bookings/{bookingId}/payments")
+    suspend fun createPayment(
+        @Path("propertyId") propertyId: String,
+        @Path("bookingId") bookingId: String,
+        @Body body: PaymentCreateRequest
+    ): Response<PaymentDto>
 }

app/src/main/java/com/android/trisolarispms/data/api/PayuPaymentLinkSettingsApi.kt

@@ -0,0 +1,22 @@
+package com.android.trisolarispms.data.api
+
+import com.android.trisolarispms.data.api.model.PayuPaymentLinkSettingsRequest
+import com.android.trisolarispms.data.api.model.PayuPaymentLinkSettingsResponse
+import retrofit2.Response
+import retrofit2.http.Body
+import retrofit2.http.GET
+import retrofit2.http.PUT
+import retrofit2.http.Path
+
+interface PayuPaymentLinkSettingsApi {
+    @GET("properties/{propertyId}/payu-payment-link-settings")
+    suspend fun getPayuPaymentLinkSettings(
+        @Path("propertyId") propertyId: String
+    ): Response<PayuPaymentLinkSettingsResponse>
+
+    @PUT("properties/{propertyId}/payu-payment-link-settings")
+    suspend fun updatePayuPaymentLinkSettings(
+        @Path("propertyId") propertyId: String,
+        @Body body: PayuPaymentLinkSettingsRequest
+    ): Response<PayuPaymentLinkSettingsResponse>
+}

app/src/main/java/com/android/trisolarispms/data/api/PayuSettingsApi.kt

@@ -0,0 +1,22 @@
+package com.android.trisolarispms.data.api
+
+import com.android.trisolarispms.data.api.model.PayuSettingsRequest
+import com.android.trisolarispms.data.api.model.PayuSettingsResponse
+import retrofit2.Response
+import retrofit2.http.Body
+import retrofit2.http.GET
+import retrofit2.http.PUT
+import retrofit2.http.Path
+
+interface PayuSettingsApi {
+    @GET("properties/{propertyId}/payu-settings")
+    suspend fun getPayuSettings(
+        @Path("propertyId") propertyId: String
+    ): Response<PayuSettingsResponse>
+
+    @PUT("properties/{propertyId}/payu-settings")
+    suspend fun updatePayuSettings(
+        @Path("propertyId") propertyId: String,
+        @Body body: PayuSettingsRequest
+    ): Response<PayuSettingsResponse>
+}

app/src/main/java/com/android/trisolarispms/data/api/model/PaymentModels.kt

@@ -0,0 +1,25 @@
+package com.android.trisolarispms.data.api.model
+
+data class PaymentDto(
+    val id: String? = null,
+    val bookingId: String? = null,
+    val amount: Long? = null,
+    val currency: String? = null,
+    val method: String? = null,
+    val gatewayPaymentId: String? = null,
+    val gatewayTxnId: String? = null,
+    val bankRefNum: String? = null,
+    val mode: String? = null,
+    val pgType: String? = null,
+    val payerVpa: String? = null,
+    val payerName: String? = null,
+    val paymentSource: String? = null,
+    val reference: String? = null,
+    val notes: String? = null,
+    val receivedAt: String? = null,
+    val receivedByUserId: String? = null
+)
+
+data class PaymentCreateRequest(
+    val amount: Long
+)

app/src/main/java/com/android/trisolarispms/data/api/model/PayuPaymentLinkSettingsModels.kt

@@ -0,0 +1,18 @@
+package com.android.trisolarispms.data.api.model
+
+data class PayuPaymentLinkSettingsRequest(
+    val merchantId: String,
+    val clientId: String,
+    val clientSecret: String,
+    val isTest: Boolean
+)
+
+data class PayuPaymentLinkSettingsResponse(
+    val propertyId: String? = null,
+    val configured: Boolean? = null,
+    val merchantId: String? = null,
+    val isTest: Boolean? = null,
+    val hasClientId: Boolean? = null,
+    val hasClientSecret: Boolean? = null,
+    val hasAccessToken: Boolean? = null
+)

app/src/main/java/com/android/trisolarispms/data/api/model/PayuQrModels.kt

@@ -0,0 +1,26 @@
+package com.android.trisolarispms.data.api.model
+
+import com.google.gson.JsonElement
+
+data class PayuQrRequest(
+    val amount: Long,
+    val deviceInfo: String
+)
+
+data class PayuQrResponse(
+    val txnid: String? = null,
+    val amount: Long? = null,
+    val currency: String? = null,
+    val payuResponse: JsonElement? = null
+)
+
+data class PayuLinkRequest(
+    val amount: Long
+)
+
+data class PayuLinkResponse(
+    val amount: Long? = null,
+    val currency: String? = null,
+    val paymentLink: String? = null,
+    val payuResponse: JsonElement? = null
+)

app/src/main/java/com/android/trisolarispms/data/api/model/PayuSettingsModels.kt

@@ -0,0 +1,21 @@
+package com.android.trisolarispms.data.api.model
+
+import com.google.gson.annotations.SerializedName
+
+data class PayuSettingsRequest(
+    val merchantKey: String,
+    val salt32: String? = null,
+    val salt256: String? = null,
+    @SerializedName("isTest") val isTest: Boolean,
+    val useSalt256: Boolean
+)
+
+data class PayuSettingsResponse(
+    val propertyId: String? = null,
+    val configured: Boolean? = null,
+    val merchantKey: String? = null,
+    @SerializedName("test") val isTest: Boolean? = null,
+    val useSalt256: Boolean? = null,
+    val hasSalt32: Boolean? = null,
+    val hasSalt256: Boolean? = null
+)

app/src/main/java/com/android/trisolarispms/ui/AppRoute.kt

@@ -47,6 +47,10 @@ sealed interface AppRoute {
         val bookingId: String,
         val guestId: String?
     ) : AppRoute
+    data class BookingPayments(
+        val propertyId: String,
+        val bookingId: String
+    ) : AppRoute
     data object AddProperty : AppRoute
     data class ActiveRoomStays(val propertyId: String, val propertyName: String) : AppRoute
     data class Rooms(val propertyId: String) : AppRoute
@@ -63,6 +67,13 @@ sealed interface AppRoute {
         val ratePlanId: String,
         val ratePlanCode: String
     ) : AppRoute
+    data class PayuSettings(val propertyId: String) : AppRoute
+    data class PayuQr(
+        val propertyId: String,
+        val bookingId: String,
+        val pendingAmount: Long?,
+        val guestPhone: String?
+    ) : AppRoute
     data object Amenities : AppRoute
     data object AddAmenity : AppRoute
     data class EditAmenity(val amenityId: String) : AppRoute

app/src/main/java/com/android/trisolarispms/ui/payment/BookingPaymentsScreen.kt

@@ -0,0 +1,164 @@
+package com.android.trisolarispms.ui.payment
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Spacer
+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.lazy.LazyColumn
+import androidx.compose.foundation.lazy.items
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material3.Button
+import androidx.compose.material3.Card
+import androidx.compose.material3.CardDefaults
+import androidx.compose.material3.CircularProgressIndicator
+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.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.viewmodel.compose.viewModel
+import com.android.trisolarispms.data.api.model.PaymentDto
+import java.time.OffsetDateTime
+import java.time.format.DateTimeFormatter
+
+@Composable
+@OptIn(ExperimentalMaterial3Api::class)
+fun BookingPaymentsScreen(
+    propertyId: String,
+    bookingId: String,
+    canAddCash: Boolean,
+    onBack: () -> Unit,
+    viewModel: BookingPaymentsViewModel = viewModel()
+) {
+    val state by viewModel.state.collectAsState()
+    val amountInput = remember { mutableStateOf("") }
+
+    LaunchedEffect(propertyId, bookingId) {
+        viewModel.load(propertyId, bookingId)
+    }
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = { Text("Payments") },
+                navigationIcon = {
+                    IconButton(onClick = onBack) {
+                        Icon(Icons.AutoMirrored.Default.ArrowBack, contentDescription = "Back")
+                    }
+                },
+                colors = TopAppBarDefaults.topAppBarColors()
+            )
+        }
+    ) { padding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(padding)
+                .padding(16.dp)
+        ) {
+            if (canAddCash) {
+                OutlinedTextField(
+                    value = amountInput.value,
+                    onValueChange = { amountInput.value = it.filter { ch -> ch.isDigit() } },
+                    label = { Text("Cash amount") },
+                    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
+                    modifier = Modifier.fillMaxWidth()
+                )
+                Spacer(modifier = Modifier.height(8.dp))
+                Button(
+                    onClick = {
+                        val amount = amountInput.value.toLongOrNull() ?: 0L
+                        viewModel.addCashPayment(propertyId, bookingId, amount)
+                    },
+                    enabled = !state.isLoading,
+                    modifier = Modifier.fillMaxWidth()
+                ) {
+                    Text("Add cash payment")
+                }
+                Spacer(modifier = Modifier.height(12.dp))
+            }
+            if (state.isLoading) {
+                CircularProgressIndicator()
+                Spacer(modifier = Modifier.height(8.dp))
+            }
+            state.error?.let {
+                Text(text = it, color = MaterialTheme.colorScheme.error)
+                Spacer(modifier = Modifier.height(8.dp))
+            }
+            if (!state.isLoading && state.error == null && state.payments.isEmpty()) {
+                Text(text = "No payments yet")
+            }
+            LazyColumn(
+                verticalArrangement = Arrangement.spacedBy(12.dp),
+                modifier = Modifier.fillMaxSize()
+            ) {
+                items(state.payments) { payment ->
+                    PaymentCard(payment = payment)
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun PaymentCard(payment: PaymentDto) {
+    val date = payment.receivedAt?.let {
+        runCatching { OffsetDateTime.parse(it) }.getOrNull()
+    }
+    val dateText = date?.format(DateTimeFormatter.ofPattern("dd MMM yyyy, hh:mm a"))
+    val isCash = payment.method == "CASH"
+    Card(
+        colors = CardDefaults.cardColors(
+            containerColor = if (isCash) {
+                MaterialTheme.colorScheme.tertiaryContainer
+            } else {
+                MaterialTheme.colorScheme.surfaceVariant
+            }
+        ),
+        modifier = Modifier.fillMaxWidth()
+    ) {
+        Column(modifier = Modifier.padding(12.dp)) {
+            val amountText = buildString {
+                append(payment.amount?.toString() ?: "-")
+                payment.currency?.let { append(" $it") }
+            }
+            Text(text = amountText, style = MaterialTheme.typography.titleMedium)
+            payment.method?.let {
+                Text(text = "Method: $it", style = MaterialTheme.typography.bodySmall)
+            }
+            payment.payerVpa?.takeIf { it.isNotBlank() }?.let {
+                Text(text = "UPI: $it", style = MaterialTheme.typography.bodySmall)
+            }
+            payment.payerName?.takeIf { it.isNotBlank() }?.let {
+                Text(text = "Payer: $it", style = MaterialTheme.typography.bodySmall)
+            }
+            dateText?.let {
+                Text(text = "Received: $it", style = MaterialTheme.typography.bodySmall)
+            }
+            payment.reference?.takeIf { it.isNotBlank() }?.let {
+                Text(text = "Ref: $it", style = MaterialTheme.typography.bodySmall)
+            }
+            payment.notes?.takeIf { it.isNotBlank() }?.let {
+                Text(text = it, style = MaterialTheme.typography.bodySmall)
+            }
+        }
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payment/BookingPaymentsState.kt

@@ -0,0 +1,9 @@
+package com.android.trisolarispms.ui.payment
+
+import com.android.trisolarispms.data.api.model.PaymentDto
+
+data class BookingPaymentsState(
+    val isLoading: Boolean = false,
+    val error: String? = null,
+    val payments: List<PaymentDto> = emptyList()
+)

app/src/main/java/com/android/trisolarispms/ui/payment/BookingPaymentsViewModel.kt

@@ -0,0 +1,90 @@
+package com.android.trisolarispms.ui.payment
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.trisolarispms.data.api.ApiClient
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+class BookingPaymentsViewModel : ViewModel() {
+    private val _state = MutableStateFlow(BookingPaymentsState())
+    val state: StateFlow<BookingPaymentsState> = _state
+
+    fun load(propertyId: String, bookingId: String) {
+        viewModelScope.launch {
+            _state.update { it.copy(isLoading = true, error = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.listPayments(propertyId, bookingId)
+                val body = response.body()
+                if (response.isSuccessful && body != null) {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            payments = body,
+                            error = null
+                        )
+                    }
+                } else {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            error = "Load failed: ${response.code()}"
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        error = e.localizedMessage ?: "Load failed"
+                    )
+                }
+            }
+        }
+    }
+
+    fun addCashPayment(propertyId: String, bookingId: String, amount: Long) {
+        if (amount <= 0) {
+            _state.update { it.copy(error = "Amount must be greater than 0") }
+            return
+        }
+        viewModelScope.launch {
+            _state.update { it.copy(isLoading = true, error = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.createPayment(
+                    propertyId = propertyId,
+                    bookingId = bookingId,
+                    body = com.android.trisolarispms.data.api.model.PaymentCreateRequest(amount = amount)
+                )
+                val body = response.body()
+                if (response.isSuccessful && body != null) {
+                    _state.update { current ->
+                        current.copy(
+                            isLoading = false,
+                            payments = listOf(body) + current.payments,
+                            error = null
+                        )
+                    }
+                } else {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            error = "Create failed: ${response.code()}"
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        error = e.localizedMessage ?: "Create failed"
+                    )
+                }
+            }
+        }
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payu/PayuPaymentLinkSettingsState.kt

@@ -0,0 +1,16 @@
+package com.android.trisolarispms.ui.payu
+
+data class PayuPaymentLinkSettingsState(
+    val merchantId: String = "",
+    val clientId: String = "",
+    val clientSecret: String = "",
+    val isTest: Boolean = false,
+    val configured: Boolean = false,
+    val hasClientId: Boolean = false,
+    val hasClientSecret: Boolean = false,
+    val hasAccessToken: Boolean = false,
+    val isLoading: Boolean = false,
+    val isSaving: Boolean = false,
+    val error: String? = null,
+    val message: String? = null
+)

app/src/main/java/com/android/trisolarispms/ui/payu/PayuPaymentLinkSettingsViewModel.kt

@@ -0,0 +1,120 @@
+package com.android.trisolarispms.ui.payu
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.trisolarispms.data.api.ApiClient
+import com.android.trisolarispms.data.api.model.PayuPaymentLinkSettingsRequest
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+class PayuPaymentLinkSettingsViewModel : ViewModel() {
+    private val _state = MutableStateFlow(PayuPaymentLinkSettingsState())
+    val state: StateFlow<PayuPaymentLinkSettingsState> = _state
+
+    fun load(propertyId: String) {
+        viewModelScope.launch {
+            _state.update { it.copy(isLoading = true, error = null, message = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.getPayuPaymentLinkSettings(propertyId)
+                val body = response.body()
+                if (response.isSuccessful && body != null) {
+                    _state.update {
+                        it.copy(
+                            merchantId = body.merchantId.orEmpty(),
+                            isTest = body.isTest == true,
+                            configured = body.configured == true,
+                            hasClientId = body.hasClientId == true,
+                            hasClientSecret = body.hasClientSecret == true,
+                            hasAccessToken = body.hasAccessToken == true,
+                            clientId = "",
+                            clientSecret = "",
+                            isLoading = false,
+                            error = null
+                        )
+                    }
+                } else {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            error = "Load failed: ${response.code()}",
+                            message = null
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        error = e.localizedMessage ?: "Load failed",
+                        message = null
+                    )
+                }
+            }
+        }
+    }
+
+    fun onMerchantIdChange(value: String) {
+        _state.update { it.copy(merchantId = value, error = null) }
+    }
+
+    fun onClientIdChange(value: String) {
+        _state.update { it.copy(clientId = value, error = null) }
+    }
+
+    fun onClientSecretChange(value: String) {
+        _state.update { it.copy(clientSecret = value, error = null) }
+    }
+
+    fun onIsTestChange(value: Boolean) {
+        _state.update { it.copy(isTest = value, error = null) }
+    }
+
+    fun save(propertyId: String) {
+        val current = state.value
+        val merchantId = current.merchantId.trim()
+        val clientId = current.clientId.trim()
+        val clientSecret = current.clientSecret.trim()
+        if (merchantId.isBlank() || clientId.isBlank() || clientSecret.isBlank()) {
+            _state.update { it.copy(error = "All fields are required") }
+            return
+        }
+        viewModelScope.launch {
+            _state.update { it.copy(isSaving = true, error = null, message = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.updatePayuPaymentLinkSettings(
+                    propertyId = propertyId,
+                    body = PayuPaymentLinkSettingsRequest(
+                        merchantId = merchantId,
+                        clientId = clientId,
+                        clientSecret = clientSecret,
+                        isTest = current.isTest
+                    )
+                )
+                if (response.isSuccessful) {
+                    _state.update { it.copy(isSaving = false, message = "Saved", error = null) }
+                    load(propertyId)
+                } else {
+                    _state.update {
+                        it.copy(
+                            isSaving = false,
+                            error = "Save failed: ${response.code()}",
+                            message = null
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isSaving = false,
+                        error = e.localizedMessage ?: "Save failed",
+                        message = null
+                    )
+                }
+            }
+        }
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payu/PayuQrScreen.kt

@@ -0,0 +1,189 @@
+package com.android.trisolarispms.ui.payu
+
+import android.graphics.Bitmap
+import android.content.Intent
+import android.net.Uri
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+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.rememberScrollState
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material3.Button
+import androidx.compose.material3.CircularProgressIndicator
+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.Scaffold
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.platform.LocalClipboardManager
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.text.AnnotatedString
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.viewmodel.compose.viewModel
+import com.google.zxing.BarcodeFormat
+import com.google.zxing.qrcode.QRCodeWriter
+import com.google.zxing.common.BitMatrix
+
+@Composable
+@OptIn(ExperimentalMaterial3Api::class)
+fun PayuQrScreen(
+    propertyId: String,
+    bookingId: String,
+    pendingAmount: Long?,
+    guestPhone: String?,
+    onBack: () -> Unit,
+    viewModel: PayuQrViewModel = viewModel()
+) {
+    val state by viewModel.state.collectAsState()
+    val clipboard = LocalClipboardManager.current
+    val context = LocalContext.current
+
+    LaunchedEffect(pendingAmount) {
+        viewModel.setInitialAmount(pendingAmount)
+    }
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = { Text("PayU QR") },
+                navigationIcon = {
+                    IconButton(onClick = onBack) {
+                        Icon(Icons.AutoMirrored.Default.ArrowBack, contentDescription = "Back")
+                    }
+                },
+                colors = TopAppBarDefaults.topAppBarColors()
+            )
+        }
+    ) { padding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(padding)
+                .padding(24.dp)
+                .verticalScroll(rememberScrollState()),
+            verticalArrangement = Arrangement.Top
+        ) {
+            OutlinedTextField(
+                value = state.amountInput,
+                onValueChange = viewModel::onAmountChange,
+                label = { Text("Amount") },
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
+                modifier = Modifier.fillMaxWidth()
+            )
+            Spacer(modifier = Modifier.height(12.dp))
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                horizontalArrangement = Arrangement.spacedBy(12.dp),
+                verticalAlignment = Alignment.CenterVertically
+            ) {
+                Button(
+                    onClick = {
+                        if (!guestPhone.isNullOrBlank()) {
+                            viewModel.generateLink(propertyId, bookingId) { link ->
+                                val uri = Uri.parse("smsto:${guestPhone}")
+                                val intent = Intent(Intent.ACTION_SENDTO, uri)
+                                    .putExtra("sms_body", "Pay using this link: $link")
+                                context.startActivity(intent)
+                            }
+                        }
+                    },
+                    enabled = !state.isLoading && !guestPhone.isNullOrBlank(),
+                    modifier = Modifier.weight(1f)
+                ) {
+                    Text("Share Link")
+                }
+                Button(
+                    onClick = { viewModel.generate(propertyId, bookingId) },
+                    enabled = !state.isLoading,
+                    modifier = Modifier.weight(1f)
+                ) {
+                    if (state.isLoading) {
+                        CircularProgressIndicator(
+                            modifier = Modifier
+                                .height(16.dp)
+                                .padding(end = 8.dp),
+                            strokeWidth = 2.dp
+                        )
+                        Text("Generating...")
+                    } else {
+                        Text("Generate QR")
+                    }
+                }
+            }
+
+            state.error?.let {
+                Spacer(modifier = Modifier.height(12.dp))
+                Text(text = it, color = MaterialTheme.colorScheme.error)
+            }
+
+            if (!state.qrString.isNullOrBlank()) {
+                Spacer(modifier = Modifier.height(16.dp))
+                val qrBitmap = remember(state.qrString) { state.qrString?.let { createQrBitmap(it) } }
+                qrBitmap?.let {
+                    androidx.compose.foundation.Image(
+                        bitmap = it.asImageBitmap(),
+                        contentDescription = "PayU QR",
+                        modifier = Modifier
+                            .fillMaxWidth()
+                            .height(240.dp)
+                    )
+                }
+                Spacer(modifier = Modifier.height(12.dp))
+                Row(
+                    modifier = Modifier.fillMaxWidth(),
+                    horizontalArrangement = Arrangement.SpaceBetween,
+                    verticalAlignment = Alignment.CenterVertically
+                ) {
+                    Text(
+                        text = "Amount: ${state.amount ?: "-"} ${state.currency ?: ""}",
+                        style = MaterialTheme.typography.bodyMedium
+                    )
+                    Button(
+                        onClick = {
+                            clipboard.setText(AnnotatedString(state.qrString.orEmpty()))
+                        }
+                    ) {
+                        Text("Copy QR string")
+                    }
+                }
+            }
+        }
+    }
+}
+
+private fun createQrBitmap(content: String, size: Int = 600): Bitmap {
+    val matrix: BitMatrix = QRCodeWriter().encode(content, BarcodeFormat.QR_CODE, size, size)
+    val width = matrix.width
+    val height = matrix.height
+    val pixels = IntArray(width * height)
+    for (y in 0 until height) {
+        val offset = y * width
+        for (x in 0 until width) {
+            pixels[offset + x] = if (matrix.get(x, y)) 0xFF000000.toInt() else 0xFFFFFFFF.toInt()
+        }
+    }
+    return Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888).apply {
+        setPixels(pixels, 0, width, 0, 0, width, height)
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payu/PayuQrState.kt

@@ -0,0 +1,14 @@
+package com.android.trisolarispms.ui.payu
+
+data class PayuQrState(
+    val deviceInfo: String = "",
+    val amountInput: String = "",
+    val isLoading: Boolean = false,
+    val error: String? = null,
+    val txnId: String? = null,
+    val amount: Long? = null,
+    val currency: String? = null,
+    val qrString: String? = null,
+    val payuResponseRaw: String? = null,
+    val paymentLink: String? = null
+)

app/src/main/java/com/android/trisolarispms/ui/payu/PayuQrViewModel.kt

@@ -0,0 +1,159 @@
+package com.android.trisolarispms.ui.payu
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.trisolarispms.data.api.ApiClient
+import com.android.trisolarispms.data.api.model.PayuLinkRequest
+import com.android.trisolarispms.data.api.model.PayuQrRequest
+import com.google.gson.Gson
+import com.google.gson.JsonElement
+import com.google.gson.JsonObject
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+class PayuQrViewModel : ViewModel() {
+    private val gson = Gson()
+    private val _state = MutableStateFlow(
+        PayuQrState(deviceInfo = buildDeviceInfo())
+    )
+    val state: StateFlow<PayuQrState> = _state
+
+    fun onAmountChange(value: String) {
+        val digits = value.filter { it.isDigit() }
+        _state.update { it.copy(amountInput = digits, error = null) }
+    }
+
+    fun setInitialAmount(amount: Long?) {
+        if (amount == null || amount <= 0) return
+        _state.update { current ->
+            if (current.amountInput.isBlank()) {
+                current.copy(amountInput = amount.toString())
+            } else {
+                current
+            }
+        }
+    }
+
+    fun generate(propertyId: String, bookingId: String) {
+        val current = state.value
+        val amount = current.amountInput.toLongOrNull()?.takeIf { it > 0 }
+        if (amount == null) {
+            _state.update { it.copy(error = "Amount is required") }
+            return
+        }
+        viewModelScope.launch {
+            _state.update { it.copy(isLoading = true, error = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.generatePayuQr(
+                    propertyId = propertyId,
+                    bookingId = bookingId,
+                    body = PayuQrRequest(
+                        amount = amount,
+                        deviceInfo = current.deviceInfo
+                    )
+                )
+                val body = response.body()
+                if (response.isSuccessful && body != null) {
+                    val (qrString, rawPayload) = extractQrString(body.payuResponse)
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            txnId = body.txnid,
+                            amount = body.amount,
+                            currency = body.currency,
+                            qrString = qrString,
+                            payuResponseRaw = rawPayload,
+                            error = null
+                        )
+                    }
+                } else {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            error = "QR request failed: ${response.code()}"
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        error = e.localizedMessage ?: "QR request failed"
+                    )
+                }
+            }
+        }
+    }
+
+    fun generateLink(propertyId: String, bookingId: String, onReady: (String) -> Unit) {
+        val current = state.value
+        val amount = current.amountInput.toLongOrNull()?.takeIf { it > 0 }
+        if (amount == null) {
+            _state.update { it.copy(error = "Amount is required") }
+            return
+        }
+        viewModelScope.launch {
+            _state.update { it.copy(isLoading = true, error = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.generatePayuLink(
+                    propertyId = propertyId,
+                    bookingId = bookingId,
+                    body = PayuLinkRequest(amount = amount)
+                )
+                val body = response.body()
+                if (response.isSuccessful && body?.paymentLink != null) {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            paymentLink = body.paymentLink,
+                            amount = body.amount,
+                            currency = body.currency,
+                            error = null
+                        )
+                    }
+                    onReady(body.paymentLink)
+                } else {
+                    _state.update {
+                        it.copy(
+                            isLoading = false,
+                            error = "Link request failed: ${response.code()}"
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        error = e.localizedMessage ?: "Link request failed"
+                    )
+                }
+            }
+        }
+    }
+
+    private fun extractQrString(payuResponse: JsonElement?): Pair<String?, String?> {
+        if (payuResponse == null) return null to null
+        val raw = gson.toJson(payuResponse)
+        val root = when {
+            payuResponse.isJsonObject -> payuResponse.asJsonObject
+            payuResponse.isJsonPrimitive && payuResponse.asJsonPrimitive.isString -> {
+                runCatching {
+                    gson.fromJson(payuResponse.asString, JsonObject::class.java)
+                }.getOrNull()
+            }
+            else -> null
+        }
+        val qrString = root?.getAsJsonObject("result")?.get("qrString")?.asString
+        return qrString to raw
+    }
+
+    private fun buildDeviceInfo(): String {
+        val release = android.os.Build.VERSION.RELEASE
+        val model = android.os.Build.MODEL
+        return "Android $release; $model; PMS"
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payu/PayuSettingsScreen.kt

@@ -0,0 +1,437 @@
+package com.android.trisolarispms.ui.payu
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.Spacer
+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.pager.HorizontalPager
+import androidx.compose.foundation.pager.rememberPagerState
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.ArrowBack
+import androidx.compose.material3.Button
+import androidx.compose.material3.CircularProgressIndicator
+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.Scaffold
+import androidx.compose.material3.Switch
+import androidx.compose.material3.Tab
+import androidx.compose.material3.TabRow
+import androidx.compose.material3.Text
+import androidx.compose.material3.TopAppBar
+import androidx.compose.material3.TopAppBarDefaults
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.collectAsState
+import androidx.compose.runtime.getValue
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.text.AnnotatedString
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.unit.dp
+import androidx.lifecycle.viewmodel.compose.viewModel
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.platform.ClipboardManager
+import androidx.compose.ui.platform.LocalClipboardManager
+import kotlinx.coroutines.launch
+
+@Composable
+@OptIn(ExperimentalMaterial3Api::class)
+fun PayuSettingsScreen(
+    propertyId: String,
+    onBack: () -> Unit,
+    viewModel: PayuSettingsViewModel = viewModel(),
+    linkViewModel: PayuPaymentLinkSettingsViewModel = viewModel()
+) {
+    val state by viewModel.state.collectAsState()
+    val linkState by linkViewModel.state.collectAsState()
+    val clipboard = LocalClipboardManager.current
+    val pagerState = rememberPagerState(initialPage = 0, pageCount = { 2 })
+    val scope = rememberCoroutineScope()
+
+    LaunchedEffect(propertyId) {
+        viewModel.load(propertyId)
+        linkViewModel.load(propertyId)
+    }
+
+    Scaffold(
+        topBar = {
+            TopAppBar(
+                title = { Text("Payu Settings") },
+                navigationIcon = {
+                    IconButton(onClick = onBack) {
+                        Icon(Icons.AutoMirrored.Default.ArrowBack, contentDescription = "Back")
+                    }
+                },
+                colors = TopAppBarDefaults.topAppBarColors()
+            )
+        }
+    ) { padding ->
+        Column(
+            modifier = Modifier
+                .fillMaxSize()
+                .padding(padding)
+        ) {
+            TabRow(selectedTabIndex = pagerState.currentPage) {
+                Tab(
+                    selected = pagerState.currentPage == 0,
+                    onClick = { scope.launch { pagerState.animateScrollToPage(0) } },
+                    text = { Text("QR") }
+                )
+                Tab(
+                    selected = pagerState.currentPage == 1,
+                    onClick = { scope.launch { pagerState.animateScrollToPage(1) } },
+                    text = { Text("Payment Links") }
+                )
+            }
+            HorizontalPager(
+                state = pagerState,
+                modifier = Modifier.fillMaxSize()
+            ) { page ->
+                when (page) {
+                    0 -> PayuQrSettingsTab(
+                        propertyId = propertyId,
+                        state = state,
+                        onMerchantKeyChange = viewModel::onMerchantKeyChange,
+                        onIsTestChange = viewModel::onIsTestChange,
+                        onUseSalt256Change = viewModel::onUseSalt256Change,
+                        onSalt32Change = viewModel::onSalt32Change,
+                        onSalt256Change = viewModel::onSalt256Change,
+                        onSave = { viewModel.save(propertyId) },
+                        clipboard = clipboard
+                    )
+                    1 -> PayuPaymentLinksTab(
+                        propertyId = propertyId,
+                        state = linkState,
+                        onMerchantIdChange = linkViewModel::onMerchantIdChange,
+                        onClientIdChange = linkViewModel::onClientIdChange,
+                        onClientSecretChange = linkViewModel::onClientSecretChange,
+                        onIsTestChange = linkViewModel::onIsTestChange,
+                        onSave = { linkViewModel.save(propertyId) }
+                    )
+                }
+            }
+        }
+    }
+}
+
+@Composable
+private fun PayuQrSettingsTab(
+    propertyId: String,
+    state: PayuSettingsState,
+    onMerchantKeyChange: (String) -> Unit,
+    onIsTestChange: (Boolean) -> Unit,
+    onUseSalt256Change: (Boolean) -> Unit,
+    onSalt32Change: (String) -> Unit,
+    onSalt256Change: (String) -> Unit,
+    onSave: () -> Unit,
+    clipboard: ClipboardManager
+) {
+    Column(
+        modifier = Modifier
+            .fillMaxSize()
+            .padding(24.dp)
+            .verticalScroll(rememberScrollState()),
+        verticalArrangement = Arrangement.Top
+    ) {
+        Text(
+            text = "Payu Settings",
+            style = MaterialTheme.typography.titleMedium
+        )
+        Spacer(modifier = Modifier.height(4.dp))
+        Text(
+            text = "More payment settings will be added later. For now, configure PayU.",
+            style = MaterialTheme.typography.bodySmall
+        )
+        Spacer(modifier = Modifier.height(4.dp))
+        Text(
+            text = "Success/failure URLs are derived by the server using this property ID.",
+            style = MaterialTheme.typography.bodySmall
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        if (state.isLoading) {
+            CircularProgressIndicator()
+            Spacer(modifier = Modifier.height(12.dp))
+        }
+
+        Text(
+            text = if (state.configured) "Status: Configured" else "Status: Not configured",
+            style = MaterialTheme.typography.bodySmall
+        )
+        Spacer(modifier = Modifier.height(8.dp))
+
+        state.message?.let {
+            Text(text = it, color = MaterialTheme.colorScheme.primary)
+            Spacer(modifier = Modifier.height(8.dp))
+        }
+
+        state.error?.let {
+            Text(text = it, color = MaterialTheme.colorScheme.error)
+            Spacer(modifier = Modifier.height(8.dp))
+        }
+
+        OutlinedTextField(
+            value = state.merchantKey,
+            onValueChange = onMerchantKeyChange,
+            label = { Text("Merchant key") },
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.SpaceBetween
+        ) {
+            Text(text = "Use PayU test URL")
+            Switch(
+                checked = state.isTest,
+                onCheckedChange = onIsTestChange
+            )
+        }
+        Spacer(modifier = Modifier.height(6.dp))
+        Text(
+            text = if (state.isTest) {
+                "Base URL: https://test.payu.in/_payment"
+            } else {
+                "Base URL: https://secure.payu.in/_payment"
+            },
+            style = MaterialTheme.typography.bodySmall
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.SpaceBetween
+        ) {
+            Text(text = "Use salt256")
+            Switch(
+                checked = state.useSalt256,
+                onCheckedChange = onUseSalt256Change
+            )
+        }
+        Spacer(modifier = Modifier.height(8.dp))
+
+        if (state.useSalt256) {
+            OutlinedTextField(
+                value = state.salt256,
+                onValueChange = onSalt256Change,
+                label = { Text("Salt256") },
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+                modifier = Modifier.fillMaxWidth()
+            )
+            if (state.hasSalt256) {
+                Spacer(modifier = Modifier.height(4.dp))
+                Text(
+                    text = "Salt256 saved",
+                    style = MaterialTheme.typography.bodySmall
+                )
+            }
+        } else {
+            OutlinedTextField(
+                value = state.salt32,
+                onValueChange = onSalt32Change,
+                label = { Text("Salt32") },
+                keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+                modifier = Modifier.fillMaxWidth()
+            )
+            if (state.hasSalt32) {
+                Spacer(modifier = Modifier.height(4.dp))
+                Text(
+                    text = "Salt32 saved",
+                    style = MaterialTheme.typography.bodySmall
+                )
+            }
+        }
+
+        Spacer(modifier = Modifier.height(16.dp))
+
+        Button(
+            onClick = onSave,
+            enabled = !state.isSaving,
+            modifier = Modifier.fillMaxWidth()
+        ) {
+            if (state.isSaving) {
+                CircularProgressIndicator(
+                    modifier = Modifier
+                        .height(16.dp)
+                        .padding(end = 8.dp),
+                    strokeWidth = 2.dp
+                )
+                Text("Saving...")
+            } else {
+                Text("Save")
+            }
+        }
+
+        Spacer(modifier = Modifier.height(16.dp))
+
+        OutlinedTextField(
+            value = "https://api.hoteltrisolaris.in/properties/$propertyId/payu/return/success",
+            onValueChange = {},
+            label = { Text("Success URL") },
+            readOnly = true,
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        OutlinedTextField(
+            value = "https://api.hoteltrisolaris.in/properties/$propertyId/payu/return/failure",
+            onValueChange = {},
+            label = { Text("Failure URL") },
+            readOnly = true,
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(12.dp),
+            verticalAlignment = Alignment.CenterVertically
+        ) {
+            Button(
+                onClick = {
+                    clipboard.setText(
+                        AnnotatedString(
+                            "https://api.hoteltrisolaris.in/properties/$propertyId/payu/return/success"
+                        )
+                    )
+                }
+            ) {
+                Text("Copy success URL")
+            }
+            Button(
+                onClick = {
+                    clipboard.setText(
+                        AnnotatedString(
+                            "https://api.hoteltrisolaris.in/properties/$propertyId/payu/return/failure"
+                        )
+                    )
+                }
+            ) {
+                Text("Copy failure URL")
+            }
+        }
+        Spacer(modifier = Modifier.height(12.dp))
+    }
+}
+
+@Composable
+private fun PayuPaymentLinksTab(
+    propertyId: String,
+    state: PayuPaymentLinkSettingsState,
+    onMerchantIdChange: (String) -> Unit,
+    onClientIdChange: (String) -> Unit,
+    onClientSecretChange: (String) -> Unit,
+    onIsTestChange: (Boolean) -> Unit,
+    onSave: () -> Unit
+) {
+    Column(
+        modifier = Modifier
+            .fillMaxSize()
+            .padding(24.dp)
+            .verticalScroll(rememberScrollState()),
+        verticalArrangement = Arrangement.Top
+    ) {
+        if (state.isLoading) {
+            CircularProgressIndicator()
+            Spacer(modifier = Modifier.height(12.dp))
+        }
+        Text(
+            text = if (state.configured) "Status: Configured" else "Status: Not configured",
+            style = MaterialTheme.typography.bodySmall
+        )
+        Spacer(modifier = Modifier.height(8.dp))
+        if (state.hasClientId) {
+            Text(text = "Client ID saved", style = MaterialTheme.typography.bodySmall)
+        }
+        if (state.hasClientSecret) {
+            Text(text = "Client Secret saved", style = MaterialTheme.typography.bodySmall)
+        }
+        if (state.hasAccessToken) {
+            Text(text = "Access token available", style = MaterialTheme.typography.bodySmall)
+        }
+        Spacer(modifier = Modifier.height(12.dp))
+        Text(
+            text = "Payment Link Settings",
+            style = MaterialTheme.typography.titleMedium
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        state.message?.let {
+            Text(text = it, color = MaterialTheme.colorScheme.primary)
+            Spacer(modifier = Modifier.height(8.dp))
+        }
+        state.error?.let {
+            Text(text = it, color = MaterialTheme.colorScheme.error)
+            Spacer(modifier = Modifier.height(8.dp))
+        }
+
+        OutlinedTextField(
+            value = state.merchantId,
+            onValueChange = onMerchantIdChange,
+            label = { Text("Merchant ID") },
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+        OutlinedTextField(
+            value = state.clientId,
+            onValueChange = onClientIdChange,
+            label = { Text("Client ID") },
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+        OutlinedTextField(
+            value = state.clientSecret,
+            onValueChange = onClientSecretChange,
+            label = { Text("Client Secret") },
+            keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Ascii),
+            modifier = Modifier.fillMaxWidth()
+        )
+        Spacer(modifier = Modifier.height(12.dp))
+
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            verticalAlignment = Alignment.CenterVertically,
+            horizontalArrangement = Arrangement.SpaceBetween
+        ) {
+            Text(text = "Use PayU test environment")
+            Switch(
+                checked = state.isTest,
+                onCheckedChange = onIsTestChange
+            )
+        }
+        Spacer(modifier = Modifier.height(16.dp))
+
+        Button(
+            onClick = onSave,
+            enabled = !state.isSaving,
+            modifier = Modifier.fillMaxWidth()
+        ) {
+            if (state.isSaving) {
+                CircularProgressIndicator(
+                    modifier = Modifier
+                        .height(16.dp)
+                        .padding(end = 8.dp),
+                    strokeWidth = 2.dp
+                )
+                Text("Saving...")
+            } else {
+                Text("Save")
+            }
+        }
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/payu/PayuSettingsState.kt

@@ -0,0 +1,16 @@
+package com.android.trisolarispms.ui.payu
+
+data class PayuSettingsState(
+    val merchantKey: String = "",
+    val salt32: String = "",
+    val salt256: String = "",
+    val isTest: Boolean = false,
+    val useSalt256: Boolean = false,
+    val hasSalt32: Boolean = false,
+    val hasSalt256: Boolean = false,
+    val configured: Boolean = false,
+    val isLoading: Boolean = false,
+    val isSaving: Boolean = false,
+    val error: String? = null,
+    val message: String? = null
+)

app/src/main/java/com/android/trisolarispms/ui/payu/PayuSettingsViewModel.kt

@@ -0,0 +1,145 @@
+package com.android.trisolarispms.ui.payu
+
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.android.trisolarispms.data.api.ApiClient
+import com.android.trisolarispms.data.api.model.PayuSettingsRequest
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.update
+import kotlinx.coroutines.launch
+
+class PayuSettingsViewModel : ViewModel() {
+    private val _state = MutableStateFlow(PayuSettingsState())
+    val state: StateFlow<PayuSettingsState> = _state
+
+    fun load(propertyId: String) {
+        viewModelScope.launch {
+            loadInternal(propertyId = propertyId, showLoading = true, message = null)
+        }
+    }
+
+    fun onMerchantKeyChange(value: String) {
+        _state.update { it.copy(merchantKey = value, error = null) }
+    }
+
+    fun onSalt32Change(value: String) {
+        _state.update { it.copy(salt32 = value, error = null) }
+    }
+
+    fun onSalt256Change(value: String) {
+        _state.update { it.copy(salt256 = value, error = null) }
+    }
+
+    fun onIsTestChange(value: Boolean) {
+        _state.update { it.copy(isTest = value, error = null) }
+    }
+
+    fun onUseSalt256Change(value: Boolean) {
+        _state.update { it.copy(useSalt256 = value, error = null) }
+    }
+
+    fun save(propertyId: String) {
+        val current = state.value
+        val merchantKey = current.merchantKey.trim()
+        val salt32 = current.salt32.trim()
+        val salt256 = current.salt256.trim()
+
+        if (merchantKey.isBlank()) {
+            _state.update { it.copy(error = "Merchant key is required") }
+            return
+        }
+        if (current.useSalt256 && salt256.isBlank() && !current.hasSalt256) {
+            _state.update { it.copy(error = "Salt256 is required") }
+            return
+        }
+        if (!current.useSalt256 && salt32.isBlank() && !current.hasSalt32) {
+            _state.update { it.copy(error = "Salt32 is required") }
+            return
+        }
+
+        viewModelScope.launch {
+            _state.update { it.copy(isSaving = true, error = null, message = null) }
+            try {
+                val api = ApiClient.create()
+                val response = api.updatePayuSettings(
+                    propertyId = propertyId,
+                    body = PayuSettingsRequest(
+                        merchantKey = merchantKey,
+                        salt32 = salt32.ifBlank { null },
+                        salt256 = salt256.ifBlank { null },
+                        isTest = current.isTest,
+                        useSalt256 = current.useSalt256
+                    )
+                )
+                if (response.isSuccessful) {
+                    loadInternal(propertyId = propertyId, showLoading = false, message = "Saved")
+                } else {
+                    _state.update {
+                        it.copy(
+                            isSaving = false,
+                            error = "Save failed: ${response.code()}",
+                            message = null
+                        )
+                    }
+                }
+            } catch (e: Exception) {
+                _state.update {
+                    it.copy(
+                        isSaving = false,
+                        error = e.localizedMessage ?: "Save failed",
+                        message = null
+                    )
+                }
+            }
+        }
+    }
+
+    private suspend fun loadInternal(propertyId: String, showLoading: Boolean, message: String?) {
+        if (showLoading) {
+            _state.update { it.copy(isLoading = true, error = null, message = message) }
+        } else {
+            _state.update { it.copy(error = null, message = message) }
+        }
+        try {
+            val api = ApiClient.create()
+            val response = api.getPayuSettings(propertyId)
+            val body = response.body()
+            if (response.isSuccessful && body != null) {
+                _state.update {
+                    it.copy(
+                        merchantKey = body.merchantKey.orEmpty(),
+                        isTest = body.isTest == true,
+                        useSalt256 = body.useSalt256 == true,
+                        hasSalt32 = body.hasSalt32 == true,
+                        hasSalt256 = body.hasSalt256 == true,
+                        configured = body.configured == true,
+                        salt32 = "",
+                        salt256 = "",
+                        isLoading = false,
+                        isSaving = false,
+                        error = null
+                    )
+                }
+            } else {
+                _state.update {
+                    it.copy(
+                        isLoading = false,
+                        isSaving = false,
+                        error = "Load failed: ${response.code()}",
+                        message = null
+                    )
+                }
+            }
+        } catch (e: Exception) {
+            _state.update {
+                it.copy(
+                    isLoading = false,
+                    isSaving = false,
+                    error = e.localizedMessage ?: "Load failed",
+                    message = null
+                )
+            }
+        }
+    }
+}

app/src/main/java/com/android/trisolarispms/ui/roomstay/ActiveRoomStaysScreen.kt

@@ -15,6 +15,7 @@ import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Add
 import androidx.compose.material.icons.filled.ArrowBack
 import androidx.compose.material.icons.filled.MeetingRoom
+import androidx.compose.material.icons.filled.Payment
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
@@ -51,6 +52,8 @@ fun ActiveRoomStaysScreen(
     onBack: () -> Unit,
     onViewRooms: () -> Unit,
     onCreateBooking: () -> Unit,
+    showPayuSettings: Boolean,
+    onPayuSettings: () -> Unit,
     onManageRoomStay: (BookingListItem) -> Unit,
     onViewBookingStays: (BookingListItem) -> Unit,
     onOpenBookingDetails: (BookingListItem) -> Unit,
@@ -76,6 +79,11 @@ fun ActiveRoomStaysScreen(
                     IconButton(onClick = onViewRooms) {
                         Icon(Icons.Default.MeetingRoom, contentDescription = "Available Rooms")
                     }
+                    if (showPayuSettings) {
+                        IconButton(onClick = onPayuSettings) {
+                            Icon(Icons.Default.Payment, contentDescription = "Payu Settings")
+                        }
+                    }
                 },
                 colors = TopAppBarDefaults.topAppBarColors()
             )

app/src/main/java/com/android/trisolarispms/ui/roomstay/BookingDetailsTabsScreen.kt

@@ -5,11 +5,14 @@ import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.ColumnScope
 import androidx.compose.foundation.layout.Row
+import androidx.compose.foundation.layout.RowScope
 import androidx.compose.foundation.layout.Spacer
 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.layout.width
 import androidx.compose.foundation.pager.HorizontalPager
 import androidx.compose.foundation.pager.rememberPagerState
 import androidx.compose.foundation.rememberScrollState
@@ -17,6 +20,8 @@ import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.ArrowBack
 import androidx.compose.material.icons.filled.Edit
+import androidx.compose.material.icons.filled.QrCode
+import androidx.compose.material.icons.filled.ReceiptLong
 import androidx.compose.material3.Card
 import androidx.compose.material3.CardDefaults
 import androidx.compose.material3.CircularProgressIndicator
@@ -67,6 +72,8 @@ fun BookingDetailsTabsScreen(
     onBack: () -> Unit,
     onEditCheckout: (String?, String?) -> Unit,
     onEditSignature: (String) -> Unit,
+    onOpenPayuQr: (Long?, String?) -> Unit,
+    onOpenPayments: () -> Unit,
     staysViewModel: BookingRoomStaysViewModel = viewModel(),
     detailsViewModel: BookingDetailsViewModel = viewModel()
 ) {
@@ -126,7 +133,9 @@ fun BookingDetailsTabsScreen(
                     isLoading = detailsState.isLoading,
                     error = detailsState.error,
                     onEditCheckout = onEditCheckout,
-                    onEditSignature = onEditSignature
+                    onEditSignature = onEditSignature,
+                    onOpenPayuQr = onOpenPayuQr,
+                    onOpenPayments = onOpenPayments
                 )
                     1 -> BookingRoomStaysTabContent(staysState, staysViewModel)
                 }
@@ -143,7 +152,9 @@ private fun GuestInfoTabContent(
     isLoading: Boolean,
     error: String?,
     onEditCheckout: (String?, String?) -> Unit,
-    onEditSignature: (String) -> Unit
+    onEditSignature: (String) -> Unit,
+    onOpenPayuQr: (Long?, String?) -> Unit,
+    onOpenPayments: () -> Unit
 ) {
     val displayZone = remember { ZoneId.of("Asia/Kolkata") }
     val dateFormatter = remember { DateTimeFormatter.ofPattern("dd/MM/yyyy") }
@@ -219,7 +230,33 @@ private fun GuestInfoTabContent(
             }
         }
 
-        SectionCard(title = "Calculations") {
+        val hasGuestName = details?.guestName?.isNotBlank() == true
+        val hasGuestPhone = details?.guestPhone?.isNotBlank() == true
+        val hasPending = (details?.pending ?: 0L) > 1L
+        SectionCard(
+            title = "Calculations",
+            headerContent = {
+                if (hasGuestName && hasGuestPhone && hasPending) {
+                    IconButton(onClick = { onOpenPayuQr(details.pending, details.guestPhone) }) {
+                        Icon(
+                            imageVector = Icons.Default.QrCode,
+                            contentDescription = "PayU QR",
+                            tint = MaterialTheme.colorScheme.primary
+                        )
+                    }
+                }
+                IconButton(
+                    onClick = onOpenPayments,
+                    modifier = Modifier.size(36.dp)
+                ) {
+                    Icon(
+                        imageVector = Icons.Default.ReceiptLong,
+                        contentDescription = "Payments",
+                        tint = MaterialTheme.colorScheme.primary
+                    )
+                }
+            }
+        ) {
             GuestDetailRow(label = "Amount Collected", value = details?.amountCollected?.toString())
             GuestDetailRow(label = "Rent per day", value = details?.totalNightlyRate?.toString())
             GuestDetailRow(label = "Expected pay", value = details?.expectedPay?.toString())
@@ -263,13 +300,24 @@ private fun GuestDetailRow(label: String, value: String?) {
 }
 
 @Composable
-private fun SectionCard(title: String, content: @Composable ColumnScope.() -> Unit) {
+private fun SectionCard(
+    title: String,
+    headerContent: (@Composable RowScope.() -> Unit)? = null,
+    content: @Composable ColumnScope.() -> Unit
+) {
     Card(
         colors = CardDefaults.cardColors(containerColor = MaterialTheme.colorScheme.surface),
         modifier = Modifier.fillMaxWidth()
     ) {
         Column(modifier = Modifier.padding(16.dp)) {
-            Text(text = title, style = MaterialTheme.typography.titleMedium)
+            Row(
+                modifier = Modifier.fillMaxWidth(),
+                verticalAlignment = Alignment.CenterVertically
+            ) {
+                Text(text = title, style = MaterialTheme.typography.titleMedium)
+                Spacer(modifier = Modifier.weight(1f))
+                headerContent?.invoke(this)
+            }
             Spacer(modifier = Modifier.height(8.dp))
             content()
         }

gradle/libs.versions.toml

@@ -22,6 +22,7 @@ coilSvg = "2.7.0"
 lottieCompose = "6.7.1"
 calendarCompose = "2.6.0"
 libphonenumber = "8.13.34"
+zxingCore = "3.5.3"
 
 [libraries]
 androidx-core-ktx = { group = "androidx.core", name = "core-ktx", version.ref = "coreKtx" }
@@ -54,6 +55,7 @@ coil-svg = { group = "io.coil-kt", name = "coil-svg", version.ref = "coilSvg" }
 lottie-compose = { group = "com.airbnb.android", name = "lottie-compose", version.ref = "lottieCompose" }
 calendar-compose = { group = "com.kizitonwose.calendar", name = "compose", version.ref = "calendarCompose" }
 libphonenumber = { group = "com.googlecode.libphonenumber", name = "libphonenumber", version.ref = "libphonenumber" }
+zxing-core = { group = "com.google.zxing", name = "core", version.ref = "zxingCore" }
 
 [plugins]
 android-application = { id = "com.android.application", version.ref = "agp" }