init

app/src/main/java/cc/n0th1ng/tripmoney/viewmodel/ExpenseAndCategoryViewModel.kt

@@ -1,35 +1,39 @@
 package cc.n0th1ng.tripmoney.viewmodel
 
+import android.os.Build
+import androidx.annotation.RequiresApi
 import androidx.lifecycle.ViewModel
-import androidx.lifecycle.ViewModelProvider
 import androidx.lifecycle.viewModelScope
 import androidx.paging.PagingData
 import androidx.paging.cachedIn
+import androidx.paging.map
+import cc.n0th1ng.tripmoney.data.dto.SummaryPerCategory
 import cc.n0th1ng.tripmoney.data.entity.Category
 import cc.n0th1ng.tripmoney.data.entity.Expense
 import cc.n0th1ng.tripmoney.data.entity.ExpenseDto
 import cc.n0th1ng.tripmoney.data.repository.CategoryRepository
 import cc.n0th1ng.tripmoney.data.repository.ExchangeRateRepository
 import cc.n0th1ng.tripmoney.data.repository.ExpenseRepository
-import cc.n0th1ng.tripmoney.service.ExchangeService
+import cc.n0th1ng.tripmoney.data.repository.TripRepository
 import cc.n0th1ng.tripmoney.utils.Currencies
 import dagger.hilt.android.lifecycle.HiltViewModel
-import io.ktor.client.request.get
 import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.flow
+import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.launch
-import java.time.LocalDate
+import kotlinx.coroutines.runBlocking
+import java.time.LocalDateTime
 import javax.inject.Inject
 
 @HiltViewModel
-class ExpenseAndCategoryViewModel @Inject constructor(
+open class ExpenseAndCategoryViewModel @Inject constructor(
     private val expenseRepo: ExpenseRepository,
     private val categoryRepo: CategoryRepository,
-    private val exchangeRateRepository: ExchangeRateRepository
+    private val exchangeRateRepository: ExchangeRateRepository,
+    private val tripRepo: TripRepository
 ) : ViewModel() {
 
     fun getExpenses(tripId: Int): Flow<PagingData<ExpenseDto>> =
-        expenseRepo.getExpenses(tripId).cachedIn(viewModelScope)
+        expenseRepo.getExpensesPaged(tripId).cachedIn(viewModelScope)
 
     fun save(expense: Expense) {
         viewModelScope.launch {
@@ -51,9 +55,81 @@ class ExpenseAndCategoryViewModel @Inject constructor(
         }
     }
 
-    fun convertAmount(amount: Double, base: Currencies, target: Currencies, date: LocalDate): Flow<Double> {
-        return flow {
-            emit(amount * exchangeRateRepository.getRate(base, target, date))
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun getSummaryPerCategory(tripId: Int): Flow<List<SummaryPerCategory>> {
+        val tripCurrency = tripRepo.getTrip(tripId)?.currency ?: Currencies.default().name
+        return getExpensesWithConvertedAmounts(tripId)
+            .map { list ->
+                // Compute summary
+                val sumOfAll = list.sumOf { it.convertedAmount }
+                list.groupBy { it.expenseDto.category }
+                    .map { (category, expenses) ->
+                        val total = expenses.sumOf { it.convertedAmount }
+                        SummaryPerCategory(
+                            category = category,
+                            amount = total,
+                            percent = (total / sumOfAll).toFloat(),
+                            currency = Currencies.valueOf(tripCurrency)
+                        )
+                    }.sortedBy { it.percent }.reversed()
+            }
+    }
+
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun getExpensesWithConvertedAmounts(tripId: Int): Flow<List<ExpenseDtoWithConvertedAmount>> {
+        return expenseRepo.getExpenses(tripId)
+            .map { list ->
+                list.map { expenseDto ->
+                    val convertedAmount =
+                        if (expenseDto.expense.currency != expenseDto.trip.currency) {
+                            runBlocking {
+                                expenseDto.toExpenseDtoWithConvertedAmount()
+                            }
+                        } else {
+                            expenseDto.expense.amount
+                        }
+                    ExpenseDtoWithConvertedAmount(expenseDto, convertedAmount)
+                }
+            }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun getExpensesWithConvertedAmountsPaged(tripId: Int): Flow<PagingData<ExpenseDtoWithConvertedAmount>> {
+        return expenseRepo.getExpensesPaged(tripId)
+            .map { pagingData ->
+                pagingData.map { expenseDto ->
+                    val convertedAmount =
+                        if (expenseDto.expense.currency != expenseDto.trip.currency) {
+                            runBlocking {
+                                expenseDto.toExpenseDtoWithConvertedAmount()
+                            }
+                        } else {
+                            expenseDto.expense.amount
+                        }
+                    ExpenseDtoWithConvertedAmount(expenseDto, convertedAmount)
+                }
+            }
+    }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    fun clearOldRates() {
+        viewModelScope.launch {
+            exchangeRateRepository.clearOldRates()
         }
     }
+
+    @RequiresApi(Build.VERSION_CODES.O)
+    suspend fun ExpenseDto.toExpenseDtoWithConvertedAmount(): Double {
+        return exchangeRateRepository.getRate(
+            Currencies.valueOf(this.expense.currency),
+            Currencies.valueOf(this.trip.currency),
+            LocalDateTime.parse(this.expense.datetime).toLocalDate()
+        ) * this.expense.amount
+    }
+
+    data class ExpenseDtoWithConvertedAmount(
+        val expenseDto: ExpenseDto,
+        val convertedAmount: Double
+    )
 }

app/src/main/java/cc/n0th1ng/tripmoney/viewmodel/SettingsViewModel.kt

@@ -9,6 +9,7 @@ import androidx.lifecycle.ViewModelProvider
 import androidx.lifecycle.viewModelScope
 import cc.n0th1ng.tripmoney.data.repository.AppTheme
 import cc.n0th1ng.tripmoney.data.repository.PreferencesRepository
+import cc.n0th1ng.tripmoney.utils.Currencies
 import dagger.hilt.android.lifecycle.HiltViewModel
 import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.flow.SharingStarted
@@ -35,6 +36,17 @@ class SettingsViewModel @Inject constructor(
         -1
     )
 
+    val defaultCurrency = repo.defaultCurrencyFlow.stateIn(
+        viewModelScope, SharingStarted.WhileSubscribed(5000),
+        Currencies.default()
+    )
+
+    fun setDefaultCurrency(currency: Currencies) {
+        viewModelScope.launch {
+            repo.saveDefaultCurrency(currency)
+        }
+    }
+
     fun setCurrentTrip(tripId: Int) {
         viewModelScope.launch {
             repo.saveCurrentTrip(tripId)

app/src/main/java/cc/n0th1ng/tripmoney/viewmodel/TripViewModel.kt

@@ -18,6 +18,8 @@ class TripViewModel @Inject constructor(private val repository: TripRepository)
 
     fun getTrips(): Flow<PagingData<Trip>> = repository.getTrips().cachedIn(viewModelScope)
 
+    fun getTrip(tripId: Int): Trip? = repository.getTrip(tripId)
+
     fun delete(trip: Trip) {
         viewModelScope.launch {
             repository.delete(trip)